The prophase of the first division of MEIOSIS (in which homologous CHROMOSOME SEGREGATION occurs). It is divided into five stages: leptonema, zygonema, PACHYNEMA, diplonema, and diakinesis.
A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.
The three-part structure of ribbon-like proteinaceous material that serves to align and join the paired homologous CHROMOSOMES. It is formed during the ZYGOTENE STAGE of the first meiotic division. It is a prerequisite for CROSSING OVER.
The alignment of CHROMOSOMES at homologous sequences.
A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.
The stage in the first meiotic prophase, following ZYGOTENE STAGE, when CROSSING OVER between homologous CHROMOSOMES begins.
In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
The phase of cell nucleus division following PROMETAPHASE, in which the CHROMOSOMES line up across the equatorial plane of the SPINDLE APPARATUS prior to separation.
The final phase of cell nucleus division following ANAPHASE, in which two daughter nuclei are formed, the CYTOPLASM completes division, and the CHROMOSOMES lose their distinctness and are transformed into CHROMATIN threads.
Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).
Proteins that control the CELL DIVISION CYCLE. This family of proteins includes a wide variety of classes, including CYCLIN-DEPENDENT KINASES, mitogen-activated kinases, CYCLINS, and PHOSPHOPROTEIN PHOSPHATASES as well as their putative substrates such as chromatin-associated proteins, CYTOSKELETAL PROTEINS, and TRANSCRIPTION FACTORS.
The clear constricted portion of the chromosome at which the chromatids are joined and by which the chromosome is attached to the spindle during cell division.
The orderly segregation of CHROMOSOMES during MEIOSIS or MITOSIS.
A microtubule structure that forms during CELL DIVISION. It consists of two SPINDLE POLES, and sets of MICROTUBULES that may include the astral microtubules, the polar microtubules, and the kinetochore microtubules.
The reciprocal exchange of segments at corresponding positions along pairs of homologous CHROMOSOMES by symmetrical breakage and crosswise rejoining forming cross-over sites (HOLLIDAY JUNCTIONS) that are resolved during CHROMOSOME SEGREGATION. Crossing-over typically occurs during MEIOSIS but it may also occur in the absence of meiosis, for example, with bacterial chromosomes, organelle chromosomes, or somatic cell nuclear chromosomes.
The phase of cell nucleus division following PROPHASE, when the breakdown of the NUCLEAR ENVELOPE occurs and the MITOTIC SPINDLE APPARATUS enters the nuclear region and attaches to the KINETOCHORES.
A genus of the family Heteromyidae which contains 22 species. Their physiology is adapted for the conservation of water, and they seldom drink water. They are found in arid or desert habitats and travel by hopping on their hind limbs.
Nucleoproteins, which in contrast to HISTONES, are acid insoluble. They are involved in chromosomal functions; e.g. they bind selectively to DNA, stimulate transcription resulting in tissue-specific RNA synthesis and undergo specific changes in response to various hormones or phytomitogens.
Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
The process of germ cell development in the female from the primordial germ cells through OOGONIA to the mature haploid ova (OVUM).
The male gonad containing two functional parts: the SEMINIFEROUS TUBULES for the production and transport of male germ cells (SPERMATOGENESIS) and the interstitial compartment containing LEYDIG CELLS that produce ANDROGENS.
Either of the two longitudinally adjacent threads formed when a eukaryotic chromosome replicates prior to mitosis. The chromatids are held together at the centromere. Sister chromatids are derived from the same chromosome. (Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
The membrane system of the CELL NUCLEUS that surrounds the nucleoplasm. It consists of two concentric membranes separated by the perinuclear space. The structures of the envelope where it opens to the cytoplasm are called the nuclear pores (NUCLEAR PORE).
The phase of cell nucleus division following METAPHASE, in which the CHROMATIDS separate and migrate to opposite poles of the spindle.
The interval between two successive CELL DIVISIONS during which the CHROMOSOMES are not individually distinguishable. It is composed of the G phases (G1 PHASE; G0 PHASE; G2 PHASE) and S PHASE (when DNA replication occurs).
Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.
In the interphase nucleus, a condensed mass of chromatin representing an inactivated X chromosome. Each X CHROMOSOME, in excess of one, forms sex chromatin (Barr body) in the mammalian nucleus. (from King & Stansfield, A Dictionary of Genetics, 4th ed)
Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.
Structures within the nucleus of fungal cells consisting of or containing DNA, which carry genetic information essential to the cell.
The cell center, consisting of a pair of CENTRIOLES surrounded by a cloud of amorphous material called the pericentriolar region. During interphase, the centrosome nucleates microtubule outgrowth. The centrosome duplicates and, during mitosis, separates to form the two poles of the mitotic spindle (MITOTIC SPINDLE APPARATUS).
Phosphoprotein with protein kinase activity that functions in the G2/M phase transition of the CELL CYCLE. It is the catalytic subunit of the MATURATION-PROMOTING FACTOR and complexes with both CYCLIN A and CYCLIN B in mammalian cells. The maximal activity of cyclin-dependent kinase 1 is achieved when it is fully dephosphorylated.
The reproductive cells in multicellular organisms at various stages during GAMETOGENESIS.
A cyclin subtype that is transported into the CELL NUCLEUS at the end of the G2 PHASE. It stimulates the G2/M phase transition by activating CDC2 PROTEIN KINASE.
Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.
A Rec A recombinase found in eukaryotes. Rad51 is involved in DNA REPAIR of double-strand breaks.
The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.
A species of nematode that is widely used in biological, biochemical, and genetic studies.
Proteins from the nematode species CAENORHABDITIS ELEGANS. The proteins from this species are the subject of scientific interest in the area of multicellular organism MORPHOGENESIS.
A cyclin B subtype that colocalizes with MICROTUBULES during INTERPHASE and is transported into the CELL NUCLEUS at the end of the G2 PHASE.
Within most types of eukaryotic CELL NUCLEUS, a distinct region, not delimited by a membrane, in which some species of rRNA (RNA, RIBOSOMAL) are synthesized and assembled into ribonucleoprotein subunits of ribosomes. In the nucleolus rRNA is transcribed from a nucleolar organizer, i.e., a group of tandemly repeated chromosomal genes which encode rRNA and which are transcribed by RNA polymerase I. (Singleton & Sainsbury, Dictionary of Microbiology & Molecular Biology, 2d ed)
The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.
The homologous chromosomes that are dissimilar in the heterogametic sex. There are the X CHROMOSOME, the Y CHROMOSOME, and the W, Z chromosomes (in animals in which the female is the heterogametic sex (the silkworm moth Bombyx mori, for example)). In such cases the W chromosome is the female-determining and the male is ZZ. (From King & Stansfield, A Dictionary of Genetics, 4th ed)
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A genus of black-spored basidiomycetous fungi of the family Coprinaceae, order Agaricales; some species are edible.
A group of enzymes that catalyzes the phosphorylation of serine or threonine residues in proteins, with ATP or other nucleotides as phosphate donors.
A family of highly conserved serine-threonine kinases that are involved in the regulation of MITOSIS. They are involved in many aspects of cell division, including centrosome duplication, SPINDLE APPARATUS formation, chromosome alignment, attachment to the spindle, checkpoint activation, and CYTOKINESIS.
A terminal section of a chromosome which has a specialized structure and which is involved in chromosomal replication and stability. Its length is believed to be a few hundred base pairs.
The period of the CELL CYCLE following DNA synthesis (S PHASE) and preceding M PHASE (cell division phase). The CHROMOSOMES are tetraploid in this point.
The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.
The male sex chromosome, being the differential sex chromosome carried by half the male gametes and none of the female gametes in humans and in some other male-heterogametic species in which the homologue of the X chromosome has been retained.
A genus of ascomycetous fungi of the family Schizosaccharomycetaceae, order Schizosaccharomycetales.
A microtubule subunit protein found in large quantities in mammalian brain. It has also been isolated from SPERM FLAGELLUM; CILIA; and other sources. Structurally, the protein is a dimer with a molecular weight of approximately 120,000 and a sedimentation coefficient of 5.8S. It binds to COLCHICINE; VINCRISTINE; and VINBLASTINE.
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
A family of multisubunit cytoskeletal motor proteins that use the energy of ATP hydrolysis to power a variety of cellular functions. Dyneins fall into two major classes based upon structural and functional criteria.
An aurora kinase that is a component of the chromosomal passenger protein complex and is involved in the regulation of MITOSIS. It mediates proper CHROMOSOME SEGREGATION and contractile ring function during CYTOKINESIS.
Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each.
Large multiprotein complexes that bind the centromeres of the chromosomes to the microtubules of the mitotic spindle during metaphase in the cell cycle.
An organization of cells into an organ-like structure. Organoids can be generated in culture. They are also found in certain neoplasms.
The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.
Interruptions in the sugar-phosphate backbone of DNA, across both strands adjacently.
A group of enzymes catalyzing the endonucleolytic cleavage of DNA. They include members of EC 3.1.21.-, EC 3.1.22.-, EC 3.1.23.- (DNA RESTRICTION ENZYMES), EC 3.1.24.- (DNA RESTRICTION ENZYMES), and EC 3.1.25.-.
Cdh1 is an activator of the anaphase-promoting complex-cyclosome, and is involved in substrate recognition. It associates with the complex in late MITOSIS from anaphase through G1 to regulate activity of CYCLIN-DEPENDENT KINASES and to prevent premature DNA replication.
An E3 ubiquitin ligase primarily involved in regulation of the metaphase-to-anaphase transition during MITOSIS through ubiquitination of specific CELL CYCLE PROTEINS. Enzyme activity is tightly regulated through subunits and cofactors, which modulate activation, inhibition, and substrate specificity. The anaphase-promoting complex, or APC-C, is also involved in tissue differentiation in the PLACENTA, CRYSTALLINE LENS, and SKELETAL MUSCLE, and in regulation of postmitotic NEURONAL PLASTICITY and excitability.
The process of germ cell development from the primordial GERM CELLS to the mature haploid GAMETES: ova in the female (OOGENESIS) or sperm in the male (SPERMATOGENESIS).
The failure of homologous CHROMOSOMES or CHROMATIDS to segregate during MITOSIS or MEIOSIS with the result that one daughter cell has both of a pair of parental chromosomes or chromatids and the other has none.
Echinoderms having bodies of usually five radially disposed arms coalescing at the center.
A type of IN SITU HYBRIDIZATION in which target sequences are stained with fluorescent dye so their location and size can be determined using fluorescence microscopy. This staining is sufficiently distinct that the hybridization signal can be seen both in metaphase spreads and in interphase nuclei.
Nocodazole is an antineoplastic agent which exerts its effect by depolymerizing microtubules.
Reproductive bodies produced by fungi.
Complexes of enzymes that catalyze the covalent attachment of UBIQUITIN to other proteins by forming a peptide bond between the C-terminal GLYCINE of UBIQUITIN and the alpha-amino groups of LYSINE residues in the protein. The complexes play an important role in mediating the selective-degradation of short-lived and abnormal proteins. The complex of enzymes can be broken down into three components that involve activation of ubiquitin (UBIQUITIN-ACTIVATING ENZYMES), conjugation of ubiquitin to the ligase complex (UBIQUITIN-CONJUGATING ENZYMES), and ligation of ubiquitin to the substrate protein (UBIQUITIN-PROTEIN LIGASES).
The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in human and other male-heterogametic species.
A subclass of dual specificity phosphatases that play a role in the progression of the CELL CYCLE. They dephosphorylate and activate CYCLIN-DEPENDENT KINASES.
Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
A cyclin A subtype primarily found in male GERM CELLS. It may play a role in the passage of SPERMATOCYTES into meiosis I.
In gonochoristic organisms, congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. Effects from exposure to abnormal levels of GONADAL HORMONES in the maternal environment, or disruption of the function of those hormones by ENDOCRINE DISRUPTORS are included.
Protein kinase that drives both the mitotic and meiotic cycles in all eukaryotic organisms. In meiosis it induces immature oocytes to undergo meiotic maturation. In mitosis it has a role in the G2/M phase transition. Once activated by CYCLINS; MPF directly phosphorylates some of the proteins involved in nuclear envelope breakdown, chromosome condensation, spindle assembly, and the degradation of cyclins. The catalytic subunit of MPF is PROTEIN P34CDC2.
Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.
Proteins obtained from the species Schizosaccharomyces pombe. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
Compounds which increase the capacity of the male to induce conception.
Esterases are hydrolase enzymes that catalyze the hydrolysis of ester bonds, converting esters into alcohols and acids, playing crucial roles in various biological processes including metabolism and detoxification.
Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.
Complex nucleoprotein structures which contain the genomic DNA and are part of the CELL NUCLEUS of PLANTS.
High molecular weight proteins found in the MICROTUBULES of the cytoskeletal system. Under certain conditions they are required for TUBULIN assembly into the microtubules and stabilize the assembled microtubules.
An order of fungi in the phylum Ascomycota that multiply by budding. They include the telomorphic ascomycetous yeasts which are found in a very wide range of habitats.
The chromosome region which is active in nucleolus formation and which functions in the synthesis of ribosomal RNA.
The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
Very long DNA molecules and associated proteins, HISTONES, and non-histone chromosomal proteins (CHROMOSOMAL PROTEINS, NON-HISTONE). Normally 46 chromosomes, including two sex chromosomes are found in the nucleus of human cells. They carry the hereditary information of the individual.
A microtubule-associated mechanical adenosine triphosphatase, that uses the energy of ATP hydrolysis to move organelles along microtubules toward the plus end of the microtubule. The protein is found in squid axoplasm, optic lobes, and in bovine brain. Bovine kinesin is a heterotetramer composed of two heavy (120 kDa) and two light (62 kDa) chains. EC 3.6.1.-.
Structures within the CELL NUCLEUS of insect cells containing DNA.
A mature haploid female germ cell extruded from the OVARY at OVULATION.
Proteins that originate from insect species belonging to the genus DROSOPHILA. The proteins from the most intensely studied species of Drosophila, DROSOPHILA MELANOGASTER, are the subject of much interest in the area of MORPHOGENESIS and development.
Proteins found in any species of fungus.
A cyclin subtype that has specificity for CDC2 PROTEIN KINASE and CYCLIN-DEPENDENT KINASE 2. It plays a role in progression of the CELL CYCLE through G1/S and G2/M phase transitions.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
The process by which the CELL NUCLEUS is divided.
An amorphous region of electron dense material in the cytoplasm from which the MICROTUBULES polymerization is nucleated. The pericentriolar region of the CENTROSOME which surrounds the CENTRIOLES is an example.
A hardy grain crop, rye, grown in northern climates. It is the most frequent host to ergot (CLAVICEPS), the toxic fungus. Its hybrid with TRITICUM is TRITICALE, another grain.
The fusion of a spermatozoon (SPERMATOZOA) with an OVUM thus resulting in the formation of a ZYGOTE.
Microscopy in which television cameras are used to brighten magnified images that are otherwise too dark to be seen with the naked eye. It is used frequently in TELEPATHOLOGY.
The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.
Self-replicating, short, fibrous, rod-shaped organelles. Each centriole is a short cylinder containing nine pairs of peripheral microtubules, arranged so as to form the wall of the cylinder.
Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.
The chromosomal constitution of cells, in which each type of CHROMOSOME is represented twice. Symbol: 2N or 2X.
Proteins obtained from various species of Xenopus. Included here are proteins from the African clawed frog (XENOPUS LAEVIS). Many of these proteins have been the subject of scientific investigations in the area of MORPHOGENESIS and development.
An exchange of segments between the sister chromatids of a chromosome, either between the sister chromatids of a meiotic tetrad or between the sister chromatids of a duplicated somatic chromosome. Its frequency is increased by ultraviolet and ionizing radiation and other mutagenic agents and is particularly high in BLOOM SYNDROME.
The portion of chromosome material that remains condensed and is transcriptionally inactive during INTERPHASE.
The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.
The inability of the male to effect FERTILIZATION of an OVUM after a specified period of unprotected intercourse. Male sterility is permanent infertility.
Cellular proteins encoded by the c-mos genes (GENES, MOS). They function in the cell cycle to maintain MATURATION PROMOTING FACTOR in the active state and have protein-serine/threonine kinase activity. Oncogenic transformation can take place when c-mos proteins are expressed at the wrong time.
A plant species of the family POACEAE. It is a tall grass grown for its EDIBLE GRAIN, corn, used as food and animal FODDER.
A genus of small, two-winged flies containing approximately 900 described species. These organisms are the most extensively studied of all genera from the standpoint of genetics and cytology.
Regulatory signaling systems that control the progression through the CELL CYCLE. They ensure that the cell has completed, in the correct order and without mistakes, all the processes required to replicate the GENOME and CYTOPLASM, and divide them equally between two daughter cells. If cells sense they have not completed these processes or that the environment does not have the nutrients and growth hormones in place to proceed, then the cells are restrained (or "arrested") until the processes are completed and growth conditions are suitable.
Immunologically detectable substances found in the CELL NUCLEUS.
An order of fungi in the phylum ASCOMYCOTA that includes many valuable experimental organisms. There are eight families and very few anamorphic forms.
Supporting cells projecting inward from the basement membrane of SEMINIFEROUS TUBULES. They surround and nourish the developing male germ cells and secrete ANDROGEN-BINDING PROTEIN and hormones such as ANTI-MULLERIAN HORMONE. The tight junctions of Sertoli cells with the SPERMATOGONIA and SPERMATOCYTES provide a BLOOD-TESTIS BARRIER.
The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.
Elements of limited time intervals, contributing to particular results or situations.
Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.
A protein kinase encoded by the Saccharomyces cerevisiae CDC28 gene and required for progression from the G1 PHASE to the S PHASE in the CELL CYCLE.
An orphan nuclear receptor expressed mainly in the GERM CELLS of GONADS. It functions as a transcription factor that binds to a direct repeat of the sequence AGGTCA and may play a role in the regulation of EMBRYOGENESIS and germ cell differentiation.
A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
The residual framework structure of the CELL NUCLEUS that maintains many of the overall architectural features of the cell nucleus including the nuclear lamina with NUCLEAR PORE complex structures, residual CELL NUCLEOLI and an extensive fibrogranular structure in the nuclear interior. (Advan. Enzyme Regul. 2002; 42:39-52)
An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
The reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions. The major repair mechanisms are excision repair, in which defective regions in one strand are excised and resynthesized using the complementary base pairing information in the intact strand; photoreactivation repair, in which the lethal and mutagenic effects of ultraviolet light are eliminated; and post-replication repair, in which the primary lesions are not repaired, but the gaps in one daughter duplex are filled in by incorporation of portions of the other (undamaged) daughter duplex. Excision repair and post-replication repair are sometimes referred to as "dark repair" because they do not require light.
Phosphoproteins are proteins that have been post-translationally modified with the addition of a phosphate group, usually on serine, threonine or tyrosine residues, which can play a role in their regulation, function, interaction with other molecules, and localization within the cell.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
The process by which the CYTOPLASM of a cell is divided.
The functional hereditary units of HELMINTHS.
A family of herbivorous leaping MAMMALS of Australia, New Guinea, and adjacent islands. Members include kangaroos, wallabies, quokkas, and wallaroos.
The reproductive elements of lower organisms, such as BACTERIA; FUNGI; and cryptogamic plants.
CELL CYCLE regulatory signaling systems that are triggered by DNA DAMAGE or lack of nutrients during G2 PHASE. When triggered they restrain cells transitioning from G2 phase to M PHASE.
Complex nucleoprotein structures which contain the genomic DNA and are part of the CELL NUCLEUS of MAMMALS.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.
An alkaloid isolated from Colchicum autumnale L. and used as an antineoplastic.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
A suborder of HEMIPTERA, called true bugs, characterized by the possession of two pairs of wings. It includes the medically important families CIMICIDAE and REDUVIIDAE. (From Dorland, 28th ed)
Inability to reproduce after a specified period of unprotected intercourse. Reproductive sterility is permanent infertility.
Basic functional unit of plants.
A species of fruit fly much used in genetics because of the large size of its chromosomes.
Securin is involved in the control of the metaphase-anaphase transition during MITOSIS. It promotes the onset of anaphase by blocking SEPARASE function and preventing proteolysis of cohesin and separation of sister CHROMATIDS. Overexpression of securin is associated with NEOPLASTIC CELL TRANSFORMATION and tumor formation.
Highly conserved proteins that specifically bind to and activate the anaphase-promoting complex-cyclosome, promoting ubiquitination and proteolysis of cell-cycle-regulatory proteins. Cdc20 is essential for anaphase-promoting complex activity, initiation of anaphase, and cyclin proteolysis during mitosis.
Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.
A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
An OOCYTE-containing structure in the cortex of the OVARY. The oocyte is enclosed by a layer of GRANULOSA CELLS providing a nourishing microenvironment (FOLLICULAR FLUID). The number and size of follicles vary depending on the age and reproductive state of the female. The growing follicles are divided into five stages: primary, secondary, tertiary, Graafian, and atretic. Follicular growth and steroidogenesis depend on the presence of GONADOTROPINS.
The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.
Thiones are organic compounds containing a sulfur atom bonded to two carbon atoms, often found in certain drugs and naturally occurring substances, which possess various pharmacological activities.
The gamete-producing glands, OVARY or TESTIS.
Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
An aurora kinase that localizes to the CENTROSOME during MITOSIS and is involved in centrosome regulation and formation of the MITOTIC SPINDLE. Aurora A overexpression in many malignant tumor types suggests that it may be directly involved in NEOPLASTIC CELL TRANSFORMATION.
Uridine is a nucleoside, specifically a derivative of pyrimidine, that is composed of a uracil molecule joined to a ribose sugar molecule through a β-N1 glycosidic bond, and has significant roles in RNA synthesis, energy transfer, and cell signaling.
Agents that interact with TUBULIN to inhibit or promote polymerization of MICROTUBULES.
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
A major alkaloid from Colchicum autumnale L. and found also in other Colchicum species. Its primary therapeutic use is in the treatment of gout, but it has been used also in the therapy of familial Mediterranean fever (PERIODIC DISEASE).
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.
The subfamily of myosin proteins that are commonly found in muscle fibers. Myosin II is also involved a diverse array of cellular functions including cell division, transport within the GOLGI APPARATUS, and maintaining MICROVILLI structure.
A broad category of enzymes that are involved in the process of GENETIC RECOMBINATION.
Proteins found in any species of helminth.
Plant-eating orthopterans having hindlegs adapted for jumping. There are two main families: Acrididae and Romaleidae. Some of the more common genera are: Melanoplus, the most common grasshopper; Conocephalus, the eastern meadow grasshopper; and Pterophylla, the true katydid.
The fertilizing element of plants that contains the male GAMETOPHYTES.
A gene silencing phenomenon whereby specific dsRNAs (RNA, DOUBLE-STRANDED) trigger the degradation of homologous mRNA (RNA, MESSENGER). The specific dsRNAs are processed into SMALL INTERFERING RNA (siRNA) which serves as a guide for cleavage of the homologous mRNA in the RNA-INDUCED SILENCING COMPLEX. DNA METHYLATION may also be triggered during this process.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Nuclear matrix proteins that are structural components of the NUCLEAR LAMINA. They are found in most multicellular organisms.
Established cell cultures that have the potential to propagate indefinitely.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Macromolecular complexes formed from the association of defined protein subunits.
An infraclass of MAMMALS, also called Metatheria, where the young are born at an early stage of development and continue to develop in a pouch (marsupium). In contrast to Eutheria (placentals), marsupials have an incomplete PLACENTA.
A group of PROTEIN-SERINE-THREONINE KINASES which activate critical signaling cascades in double strand breaks, APOPTOSIS, and GENOTOXIC STRESS such as ionizing ultraviolet A light, thereby acting as a DNA damage sensor. These proteins play a role in a wide range of signaling mechanisms in cell cycle control.
Transport proteins that carry specific substances in the blood or across cell membranes.
The marking of biological material with a dye or other reagent for the purpose of identifying and quantitating components of tissues, cells or their extracts.
A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992)
A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
A specific inhibitor of phosphoserine/threonine protein phosphatase 1 and 2a. It is also a potent tumor promoter. (Thromb Res 1992;67(4):345-54 & Cancer Res 1993;53(2):239-41)
A family of proteins that share the F-BOX MOTIF and are involved in protein-protein interactions. They play an important role in process of protein ubiquition by associating with a variety of substrates and then associating into SCF UBIQUITIN LIGASE complexes. They are held in the ubiquitin-ligase complex via binding to SKP DOMAIN PROTEINS.
A broad category of nuclear proteins that are components of or participate in the formation of the NUCLEAR MATRIX.
Mapping of the KARYOTYPE of a cell.
The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)
Deoxyribonucleic acid that makes up the genetic material of fungi.
A form of fluorescent antibody technique commonly used to detect serum antibodies and immune complexes in tissues and microorganisms in specimens from patients with infectious diseases. The technique involves formation of an antigen-antibody complex which is labeled with fluorescein-conjugated anti-immunoglobulin antibody. (From Bennington, Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984)
An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.
An aspect of protein kinase (EC 2.7.1.37) in which serine residues in protamines and histones are phosphorylated in the presence of ATP.
A genus of protozoa, formerly also considered a fungus. Characteristics include the presence of violet to brown spores.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Methods used to study CELLS.
ANIMALS whose GENOME has been altered by GENETIC ENGINEERING, or their offspring.
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.
A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.
Genes that code for proteins that regulate the CELL DIVISION CYCLE. These genes form a regulatory network that culminates in the onset of MITOSIS by activating the p34cdc2 protein (PROTEIN P34CDC2).

Involvement of Chk1 kinase in prophase I arrest of Xenopus oocytes. (1/344)

Chk1 kinase, a DNA damage/replication G2 checkpoint kinase, has recently been shown to phosphorylate and inhibit Cdc25C, a Cdc2 Tyr-15 phosphatase, thereby directly linking the G2 checkpoint to negative regulation of Cdc2. Immature Xenopus oocytes are arrested naturally at the first meiotic prophase (prophase I) or the late G2 phase, with sustained Cdc2 Tyr-15 phosphorylation. Here we have cloned a Xenopus homolog of Chk1, determined its developmental expression, and examined its possible role in prophase I arrest of oocytes. Xenopus Chk1 protein is expressed at approximately constant levels throughout oocyte maturation and early embryogenesis. Overexpression of wild-type Chk1 in oocytes prevents the release from prophase I arrest by progesterone. Conversely, specific inhibition of endogenous Chk1 either by overexpression of a dominant-negative Chk1 mutant or by injection of a neutralizing anti-Chk1 antibody facilitates prophase I release by progesterone. Moreover, when ectopically expressed in oocytes, a Chk1-nonphosphorylatable Cdc25C mutant alone can induce prophase I release much more efficiently than wild-type Cdc25C; if endogenous Chk1 function is inhibited, however, even wild-type Cdc25C can induce the release very efficiently. These results suggest strongly that Chk1 is involved in physiological prophase I arrest of Xenopus oocytes via the direct phosphorylation and inhibition of Cdc25C. We discuss the possibility that Chk1 might function either as a G2 checkpoint kinase or as an ordinary cell cycle regulator in prophase-I-arrested oocytes.  (+info)

Intra-M phase-promoting factor phosphorylation of cyclin B at the prophase/metaphase transition. (2/344)

Activation of Cdc2-cyclin B (or M phase-promoting factor (MPF)) at the prophase/metaphase transition proceeds in two steps: dephosphorylation of Cdc2 and phosphorylation of cyclin B. We here investigated the regulation of cyclin B phosphorylation using the starfish oocyte model. Cyclin B phosphorylation is not required for Cdc2 kinase activity; both the prophase complex dephosphorylated on Cdc2 with Cdc25 and the metaphase complex dephosphorylated on cyclin B with protein phosphatase 2A display high kinase activities. An in vitro assay of cyclin B kinase activity closely mimics in vivo phosphorylation as shown by phosphopeptide maps of in vivo and in vitro phosphorylated cyclin B. We demonstrate that Cdc2 itself is the cyclin B kinase; cyclin B phosphorylation requires Cdc2 activity both in vivo (sensitivity to vitamin K3, a Cdc25 inhibitor) and in vitro (copurification with Cdc2-cyclin B, requirement of Cdc2 dephosphorylation, and sensitivity to chemical inhibitors of cyclin-dependent kinases). Furthermore, cyclin B phosphorylation occurs as an intra-M phase-promoting factor reaction as shown by the following: 1) active Cdc2 is unable to phosphorylate cyclin B associated to phosphorylated Cdc2, and 2) cyclin B phosphorylation is insensitive to enzyme/substrate dilution. We conclude that, at the prophase/metaphase transition, cyclin B is mostly phosphorylated by its own associated Cdc2 subunit.  (+info)

Phosphorylation-induced rearrangement of the histone H3 NH2-terminal domain during mitotic chromosome condensation. (3/344)

The NH2-terminal domain (N-tail) of histone H3 has been implicated in chromatin compaction and its phosphorylation at Ser10 is tightly correlated with mitotic chromosome condensation. We have developed one mAb that specifically recognizes histone H3 N-tails phosphorylated at Ser10 (H3P Ab) and another that recognizes phosphorylated and unphosphorylated H3 N-tails equally well (H3 Ab). Immunocytochemistry with the H3P Ab shows that Ser10 phosphorylation begins in early prophase, peaks before metaphase, and decreases during anaphase and telophase. Unexpectedly, the H3 Ab shows stronger immunofluorescence in mitosis than interphase, indicating that the H3 N-tail is more accessible in condensed mitotic chromatin than in decondensed interphase chromatin. In vivo ultraviolet laser cross-linking indicates that the H3 N-tail is bound to DNA in interphase cells and that binding is reduced in mitotic cells. Treatment of mitotic cells with the protein kinase inhibitor staurosporine causes histone H3 dephosphorylation and chromosome decondensation. It also decreases the accessibility of the H3 N-tail to H3 Ab and increases the binding of the N-tail to DNA. These results indicate that a phosphorylation-dependent weakening of the association between the H3 N-tail and DNA plays a role in mitotic chromosome condensation.  (+info)

Homologous chromosome pairing in wheat. (4/344)

Bread wheat is a hexaploid (AABBDD, 2n=6x=42) containing three related ancestral genomes, each having 7 chromosomes, giving 42 chromosomes in diploid cells. During meiosis true homologues are correctly associated in wild-type wheat, but a degree of association of related chromosomes (homoeologues) occurs in a mutant (ph1b). We show that the centromeres are associated in non-homologous pairs in all floral tissues studied, both in wild-type wheat and the ph1b mutant. The non-homologous centromere associations then become homologous premeiotically in wild-type wheat in both meiocytes and the tapetal cells, but not in the mutant. In wild-type wheat, the homologues are colocalised along their length at this stage, but the telomeres remain distinct. A single telomere cluster (bouquet) is formed in the meiocytes only by the onset of leptotene. The sub-telomeric regions of the homologues associate as the telomere cluster forms. The homologous associations at the telomeres and centromeres are maintained through meiotic prophase, although, during leptotene, the two homologues and also the sister chromatids within each homologue are separate along the rest of their length. As meiosis progresses, first the sister chromatids and then the homologues associate intimately. In wild-type wheat, first the centromere grouping, then the bouquet disperse by the end of zygotene.  (+info)

Bloom's syndrome protein, BLM, colocalizes with replication protein A in meiotic prophase nuclei of mammalian spermatocytes. (5/344)

Bloom's syndrome (BS) is a rare autosomal recessive disorder of humans characterized by severe pre- and postnatal growth deficiency, immunodeficiency, genomic instability, and a predisposition to a wide variety of neoplasms. The genomic instability is evidenced in BS somatic cells as a high incidence of gaps and breaks, chromatid exchanges, chromosome rearrangements, and locus-specific mutations. BS arises from a mutation in BLM, a gene encoding a protein with homology to the RecQ helicase family. Men with BS are sterile; women have reduced fertility and a shortened reproductive span. The current immunocytological study on mouse spermatocytes shows that the BLM protein is first evident as discrete foci along the synaptonemal complexes (SCs) of homologously synapsed autosomal bivalents in late zygonema of meiotic prophase. BLM foci progressively dissociate from the synapsed autosomal axes during early pachynema and are no longer seen in mid-pachynema. BLM colocalizes with the single-stranded DNA binding replication protein A, which has been shown to be involved in meiotic synapsis. However, there is a temporal delay in the appearance of BLM protein along the SCs relative to replication protein A, suggesting that BLM is required for a late step in processing of a subset of genomic DNA involved in establishment of interhomologue interactions in early meiotic prophase. In late pachynema and into diplonema, BLM is more dispersed in the nucleoplasm, especially over the chromatin most intimately associated with the SCs, suggesting a possible involvement of BLM in resolution of interlocks in preparation for homologous chromosome disjunction during anaphase I.  (+info)

Three-dimensional microscopy of the Rad51 recombination protein during meiotic prophase. (6/344)

An open question in meiosis is whether the Rad51 recombination protein functions solely in meiotic recombination or whether it is also involved in the chromosome homology search. To address this question, we have performed three-dimensional high-resolution immunofluorescence microscopy to visualize native Rad51 structures in maize male meiocytes. Maize has two closely related RAD51 genes that are expressed at low levels in differentiated tissues and at higher levels in mitotic and meiotic tissues. Cells and nuclei were specially fixed and embedded in polyacrylamide to maintain both native chromosome structure and the three dimensionality of the specimens. Analysis of Rad51 in maize meiocytes revealed that when chromosomes condense during leptotene, Rad51 is diffuse within the nucleus. Rad51 foci form on the chromosomes at the beginning of zygotene and rise to approximately 500 per nucleus by mid-zygotene when chromosomes are pairing and synapsing. During chromosome pairing, we consistently found two contiguous Rad51 foci on paired chromosomes. These paired foci may identify the sites where DNA sequence homology is being compared. During pachytene, the number of Rad51 foci drops to seven to 22 per nucleus. This higher number corresponds approximately to the number of chiasmata in maize meiosis. These observations are consistent with a role for Rad51 in the homology search phase of chromosome pairing in addition to its known role in meiotic recombination.  (+info)

Characterization of human zona pellucida glycoproteins. (7/344)

The human egg may only be fertilized by one spermatozoon to prevent polyploidy. In most mammals, the primary block to polyspermy occurs at the zona pellucida (ZP). Little is known of the human ZP and the changes occurring following fertilization to prevent polyploidy. Using antibodies directed against synthetic peptides predicted from the human ZP2 and ZP3 cDNA, we identified ZP3 as a 53-60 kDa glycoprotein and ZP2 as a 90-110 kDa glycoprotein in prophase-I oocytes. Characterization of the ZP from metaphase II arrested eggs (inseminated-unfertilized and fertilized-uncleaved), shows no visible modification of ZP3, but demonstrates that ZP2 undergoes limited proteolysis in the amino terminal domain, to a 60-73 kDa species, denoted ZP2p, which remains linked to the proteolysed fragments by intramolecular disulphide bonds. A lack of ZP2 proteolytic activity in acrosomal supernatants is consistent with an oocyte origin for the protease. The ZP2-specific protease may be released during cortical granule exocytosis which occurs during meiotic maturation and following sperm-egg fusion as part of the block to polyspermy. Since mouse ZP2 acts as a secondary sperm receptor, it is possible that intact ZP2 binds a secondary egg binding protein, whereas cleaved ZP2 does not, suggesting a possible mechanism for the block to polyspermy.  (+info)

A cytoplasmic dynein heavy chain is required for oscillatory nuclear movement of meiotic prophase and efficient meiotic recombination in fission yeast. (8/344)

Meiotic recombination requires pairing of homologous chromosomes, the mechanisms of which remain largely unknown. When pairing occurs during meiotic prophase in fission yeast, the nucleus oscillates between the cell poles driven by astral microtubules. During these oscillations, the telomeres are clustered at the spindle pole body (SPB), located at the leading edge of the moving nucleus and the rest of each chromosome dangles behind. Here, we show that the oscillatory nuclear movement of meiotic prophase is dependent on cytoplasmic dynein. We have cloned the gene encoding a cytoplasmic dynein heavy chain of fission yeast. Most of the cells disrupted for the gene show no gross defect during mitosis and complete meiosis to form four viable spores, but they lack the nuclear movements of meiotic prophase. Thus, the dynein heavy chain is required for these oscillatory movements. Consistent with its essential role in such nuclear movement, dynein heavy chain tagged with green fluorescent protein (GFP) is localized at astral microtubules and the SPB during the movements. In dynein-disrupted cells, meiotic recombination is significantly reduced, indicating that the dynein function is also required for efficient meiotic recombination. In accordance with the reduced recombination, which leads to reduced crossing over, chromosome missegregation is increased in the mutant. Moreover, both the formation of a single cluster of centromeres and the colocalization of homologous regions on a pair of homologous chromosomes are significantly inhibited in the mutant. These results strongly suggest that the dynein-driven nuclear movements of meiotic prophase are necessary for efficient pairing of homologous chromosomes in fission yeast, which in turn promotes efficient meiotic recombination.  (+info)

Meiotic Prophase I is a stage in the meiotic division of cellular reproduction that results in the formation of gametes or sex cells (sperm and egg). It is the first of five stages in Meiosis I, which is a type of cell division that reduces the chromosome number by half.

During Meiotic Prophase I, homologous chromosomes pair and form tetrads (four-stranded structures), which then undergo genetic recombination or crossing over, resulting in new combinations of alleles on the chromatids of each homologous chromosome. This stage can be further divided into several substages: leptonema, zygonema, pachynema, diplonema, and diakinesis. These substages are characterized by distinct changes in chromosome structure and behavior, including the condensation and movement of the chromosomes, as well as the formation and dissolution of the synaptonemal complex, a protein structure that holds the homologous chromosomes together during crossing over.

Overall, Meiotic Prophase I is a critical stage in meiosis that ensures genetic diversity in offspring by shuffling the genetic material between homologous chromosomes and creating new combinations of alleles.

Meiosis is a type of cell division that results in the formation of four daughter cells, each with half the number of chromosomes as the parent cell. It is a key process in sexual reproduction, where it generates gametes or sex cells (sperm and eggs).

The process of meiosis involves one round of DNA replication followed by two successive nuclear divisions, meiosis I and meiosis II. In meiosis I, homologous chromosomes pair, form chiasma and exchange genetic material through crossing over, then separate from each other. In meiosis II, sister chromatids separate, leading to the formation of four haploid cells. This process ensures genetic diversity in offspring by shuffling and recombining genetic information during the formation of gametes.

The synaptonemal complex is a protein structure that forms between two homologous chromosomes during meiosis, the type of cell division that leads to the production of gametes (sex cells). The synaptonemal complex consists of two lateral elements, which are associated with each of the homologous chromosomes, and a central element that runs parallel to the length of the complex and connects the two lateral elements.

The synaptonemal complex plays a crucial role in the process of genetic recombination, which occurs during meiosis. Genetic recombination is the exchange of genetic material between two homologous chromosomes that results in new combinations of genes on the chromosomes. This process helps to increase genetic diversity and is essential for the proper segregation of chromosomes during meiosis.

The synaptonemal complex also helps to ensure that the correct number of chromosomes are distributed to each gamete by holding the homologous chromosomes together until they can be properly aligned and separated during meiosis. Mutations in genes involved in the formation and maintenance of the synaptonemal complex can lead to fertility problems, developmental abnormalities, and other genetic disorders.

Chromosome pairing, also known as chromosome synapsis, is a process that occurs during meiosis, which is the type of cell division that results in the formation of sex cells or gametes (sperm and eggs).

In humans, each cell contains 23 pairs of chromosomes, for a total of 46 chromosomes. Of these, 22 pairs are called autosomal chromosomes, and they are similar in size and shape between the two copies in a pair. The last pair is called the sex chromosomes (X and Y), which determine the individual's biological sex.

During meiosis, homologous chromosomes (one from each parent) come together and pair up along their lengths in a process called synapsis. This pairing allows for the precise alignment of corresponding genes and genetic regions between the two homologous chromosomes. Once paired, the chromosomes exchange genetic material through a process called crossing over, which increases genetic diversity in the resulting gametes.

After crossing over, the homologous chromosomes separate during meiosis I, followed by the separation of sister chromatids (the two copies of each chromosome) during meiosis II. The end result is four haploid cells, each containing 23 chromosomes, which then develop into sperm or eggs.

Chromosome pairing is a crucial step in the process of sexual reproduction, ensuring that genetic information is accurately passed from one generation to the next while also promoting genetic diversity through recombination and independent assortment of chromosomes.

Mitosis is a type of cell division in which the genetic material of a single cell, called the mother cell, is equally distributed into two identical daughter cells. It's a fundamental process that occurs in multicellular organisms for growth, maintenance, and repair, as well as in unicellular organisms for reproduction.

The process of mitosis can be broken down into several stages: prophase, prometaphase, metaphase, anaphase, and telophase. During prophase, the chromosomes condense and become visible, and the nuclear envelope breaks down. In prometaphase, the nuclear membrane is completely disassembled, and the mitotic spindle fibers attach to the chromosomes at their centromeres.

During metaphase, the chromosomes align at the metaphase plate, an imaginary line equidistant from the two spindle poles. In anaphase, sister chromatids are pulled apart by the spindle fibers and move toward opposite poles of the cell. Finally, in telophase, new nuclear envelopes form around each set of chromosomes, and the chromosomes decondense and become less visible.

Mitosis is followed by cytokinesis, a process that divides the cytoplasm of the mother cell into two separate daughter cells. The result of mitosis and cytokinesis is two genetically identical cells, each with the same number and kind of chromosomes as the original parent cell.

The pachytene stage is a phase in the meiotic division of sex cells (gametes) such as sperm and egg cells, specifically during prophase I. In this stage, homologous chromosomes are fully paired and have formed tetrads, or four-stranded structures called chiasma where genetic recombination occurs between the non-sister chromatids of each homologous chromosome. This is a crucial step in the creation of genetic diversity in the offspring. The pachytene stage is characterized by the presence of a protein matrix called the synaptonemal complex, which holds the homologous chromosomes together and facilitates crossing over.

Chromosomes are thread-like structures that exist in the nucleus of cells, carrying genetic information in the form of genes. They are composed of DNA and proteins, and are typically present in pairs in the nucleus, with one set inherited from each parent. In humans, there are 23 pairs of chromosomes for a total of 46 chromosomes. Chromosomes come in different shapes and forms, including sex chromosomes (X and Y) that determine the biological sex of an individual. Changes or abnormalities in the number or structure of chromosomes can lead to genetic disorders and diseases.

Metaphase is a phase in the cell division process (mitosis or meiosis) where the chromosomes align in the middle of the cell, also known as the metaphase plate or equatorial plane. During this stage, each chromosome consists of two sister chromatids attached to each other by a protein complex called the centromere. The spindle fibers from opposite poles of the cell attach to the centromeres of each chromosome, and through a process called congression, they align the chromosomes in the middle of the cell. This alignment allows for accurate segregation of genetic material during the subsequent anaphase stage.

Telophase is a phase in the cell division process (mitosis or meiosis) where the chromosomes reach their most condensed form and move to the poles of the cell. The nuclear membrane begins to reform around each set of chromosomes, and the spindle fibers that were used to separate the chromosomes break down. This phase is followed by cytokinesis, where the cytoplasm of the cell divides, resulting in two separate daughter cells. In telophase I of meiosis, crossing over between homologous chromosomes has already occurred during prophase I and sister chromatids remain together until anaphase II.

An oocyte, also known as an egg cell or female gamete, is a large specialized cell found in the ovary of female organisms. It contains half the number of chromosomes as a normal diploid cell, as it is the product of meiotic division. Oocytes are surrounded by follicle cells and are responsible for the production of female offspring upon fertilization with sperm. The term "oocyte" specifically refers to the immature egg cell before it reaches full maturity and is ready for fertilization, at which point it is referred to as an ovum or egg.

Cell cycle proteins are a group of regulatory proteins that control the progression of the cell cycle, which is the series of events that take place in a eukaryotic cell leading to its division and duplication. These proteins can be classified into several categories based on their functions during different stages of the cell cycle.

The major groups of cell cycle proteins include:

1. Cyclin-dependent kinases (CDKs): CDKs are serine/threonine protein kinases that regulate key transitions in the cell cycle. They require binding to a regulatory subunit called cyclin to become active. Different CDK-cyclin complexes are activated at different stages of the cell cycle.
2. Cyclins: Cyclins are a family of regulatory proteins that bind and activate CDKs. Their levels fluctuate throughout the cell cycle, with specific cyclins expressed during particular phases. For example, cyclin D is important for the G1 to S phase transition, while cyclin B is required for the G2 to M phase transition.
3. CDK inhibitors (CKIs): CKIs are regulatory proteins that bind to and inhibit CDKs, thereby preventing their activation. CKIs can be divided into two main families: the INK4 family and the Cip/Kip family. INK4 family members specifically inhibit CDK4 and CDK6, while Cip/Kip family members inhibit a broader range of CDKs.
4. Anaphase-promoting complex/cyclosome (APC/C): APC/C is an E3 ubiquitin ligase that targets specific proteins for degradation by the 26S proteasome. During the cell cycle, APC/C regulates the metaphase to anaphase transition and the exit from mitosis by targeting securin and cyclin B for degradation.
5. Other regulatory proteins: Several other proteins play crucial roles in regulating the cell cycle, such as p53, a transcription factor that responds to DNA damage and arrests the cell cycle, and the polo-like kinases (PLKs), which are involved in various aspects of mitosis.

Overall, cell cycle proteins work together to ensure the proper progression of the cell cycle, maintain genomic stability, and prevent uncontrolled cell growth, which can lead to cancer.

A centromere is a specialized region found on chromosomes that plays a crucial role in the separation of replicated chromosomes during cell division. It is the point where the sister chromatids (the two copies of a chromosome formed during DNA replication) are joined together. The centromere contains highly repeated DNA sequences and proteins that form a complex structure known as the kinetochore, which serves as an attachment site for microtubules of the mitotic spindle during cell division.

During mitosis or meiosis, the kinetochore facilitates the movement of chromosomes by interacting with the microtubules, allowing for the accurate distribution of genetic material to the daughter cells. Centromeres can vary in their position and structure among different species, ranging from being located near the middle of the chromosome (metacentric) to being positioned closer to one end (acrocentric). The precise location and characteristics of centromeres are essential for proper chromosome segregation and maintenance of genomic stability.

Chromosome segregation is the process that occurs during cell division (mitosis or meiosis) where replicated chromosomes are separated and distributed equally into two daughter cells. Each chromosome consists of two sister chromatids, which are identical copies of genetic material. During chromosome segregation, these sister chromatids are pulled apart by a structure called the mitotic spindle and moved to opposite poles of the cell. This ensures that each new cell receives one copy of each chromosome, preserving the correct number and composition of chromosomes in the organism.

The spindle apparatus is a microtubule-based structure that plays a crucial role in the process of cell division, specifically during mitosis and meiosis. It consists of three main components:

1. The spindle poles: These are organized structures composed of microtubules and associated proteins that serve as the anchoring points for the spindle fibers. In animal cells, these poles are typically formed by centrosomes, while in plant cells, they form around nucleation sites called microtubule-organizing centers (MTOCs).
2. The spindle fibers: These are dynamic arrays of microtubules that extend between the two spindle poles. They can be categorized into three types: kinetochore fibers, which connect to the kinetochores on chromosomes; astral fibers, which radiate from the spindle poles and help position the spindle within the cell; and interpolar fibers, which lie between the two spindle poles and contribute to their separation during anaphase.
3. Regulatory proteins: Various motor proteins, such as dynein and kinesin, as well as non-motor proteins like tubulin and septins, are involved in the assembly, maintenance, and dynamics of the spindle apparatus. These proteins help to generate forces that move chromosomes, position the spindle, and ultimately segregate genetic material between two daughter cells during cell division.

The spindle apparatus is essential for ensuring accurate chromosome separation and maintaining genomic stability during cell division. Dysfunction of the spindle apparatus can lead to various abnormalities, including aneuploidy (abnormal number of chromosomes) and chromosomal instability, which have been implicated in several diseases, such as cancer and developmental disorders.

Crossing over, genetic is a process that occurs during meiosis, where homologous chromosomes exchange genetic material with each other. It is a crucial mechanism for generating genetic diversity in sexually reproducing organisms.

Here's a more detailed explanation:

During meiosis, homologous chromosomes pair up and align closely with each other. At this point, sections of the chromosomes can break off and reattach to the corresponding section on the homologous chromosome. This exchange of genetic material is called crossing over or genetic recombination.

The result of crossing over is that the two resulting chromosomes are no longer identical to each other or to the original chromosomes. Instead, they contain a unique combination of genetic material from both parents. Crossing over can lead to new combinations of alleles (different forms of the same gene) and can increase genetic diversity in the population.

Crossing over is a random process, so the location and frequency of crossover events vary between individuals and between chromosomes. The number and position of crossovers can affect the likelihood that certain genes will be inherited together or separated, which is an important consideration in genetic mapping and breeding studies.

Prometaphase is a stage in the cell division process called mitosis, where the nuclear membrane has broken down and the chromosomes are now moved into the center of the cell, also known as the metaphase plate. This movement is facilitated by the mitotic spindle, which attaches to specialized structures on the chromosomes called kinetochores. The prometaphase stage follows prophase and precedes metaphase in the mitosis process. It's characterized by the beginning of chromosome separation and the reorganization of the cell for the upcoming division into two daughter cells.

'Dipodomys' is the genus name for kangaroo rats, which are small rodents native to North America. They are called kangaroo rats due to their powerful hind legs and long tails, which they use to hop around like kangaroos. Kangaroo rats are known for their ability to survive in arid environments, as they are able to obtain moisture from the seeds they eat and can concentrate their urine to conserve water. They are also famous for their highly specialized kidneys, which allow them to produce extremely dry urine.

Chromosomal proteins, non-histone, are a diverse group of proteins that are associated with chromatin, the complex of DNA and histone proteins, but do not have the characteristic structure of histones. These proteins play important roles in various nuclear processes such as DNA replication, transcription, repair, recombination, and chromosome condensation and segregation during cell division. They can be broadly classified into several categories based on their functions, including architectural proteins, enzymes, transcription factors, and structural proteins. Examples of non-histone chromosomal proteins include high mobility group (HMG) proteins, poly(ADP-ribose) polymerases (PARPs), and condensins.

The cell nucleus is a membrane-bound organelle found in the eukaryotic cells (cells with a true nucleus). It contains most of the cell's genetic material, organized as DNA molecules in complex with proteins, RNA molecules, and histones to form chromosomes.

The primary function of the cell nucleus is to regulate and control the activities of the cell, including growth, metabolism, protein synthesis, and reproduction. It also plays a crucial role in the process of mitosis (cell division) by separating and protecting the genetic material during this process. The nuclear membrane, or nuclear envelope, surrounding the nucleus is composed of two lipid bilayers with numerous pores that allow for the selective transport of molecules between the nucleoplasm (nucleus interior) and the cytoplasm (cell exterior).

The cell nucleus is a vital structure in eukaryotic cells, and its dysfunction can lead to various diseases, including cancer and genetic disorders.

Oogenesis is the biological process of formation and maturation of female gametes, or ova or egg cells, in the ovary. It begins during fetal development and continues throughout a woman's reproductive years. The process involves the division and differentiation of a germ cell (oogonium) into an immature ovum (oocyte), which then undergoes meiotic division to form a mature ovum capable of being fertilized by sperm.

The main steps in oogenesis include:

1. Multiplication phase: The oogonia divide mitotically to increase their number.
2. Growth phase: One of the oogonia becomes primary oocyte and starts to grow, accumulating nutrients and organelles required for future development.
3. First meiotic division: The primary oocyte undergoes an incomplete first meiotic division, resulting in two haploid cells - a secondary oocyte and a smaller cell called the first polar body. This division is arrested in prophase I until puberty.
4. Second meiotic division: At ovulation or just before fertilization, the secondary oocyte completes the second meiotic division, producing another small cell, the second polar body, and a mature ovum (egg) with 23 chromosomes.
5. Fertilization: The mature ovum can be fertilized by a sperm, restoring the normal diploid number of chromosomes in the resulting zygote.

Oogenesis is a complex and highly regulated process that involves various hormonal signals and cellular interactions to ensure proper development and maturation of female gametes for successful reproduction.

The testis, also known as the testicle, is a male reproductive organ that is part of the endocrine system. It is located in the scrotum, outside of the abdominal cavity. The main function of the testis is to produce sperm and testosterone, the primary male sex hormone.

The testis is composed of many tiny tubules called seminiferous tubules, where sperm are produced. These tubules are surrounded by a network of blood vessels, nerves, and supportive tissues. The sperm then travel through a series of ducts to the epididymis, where they mature and become capable of fertilization.

Testosterone is produced in the Leydig cells, which are located in the interstitial tissue between the seminiferous tubules. Testosterone plays a crucial role in the development and maintenance of male secondary sexual characteristics, such as facial hair, deep voice, and muscle mass. It also supports sperm production and sexual function.

Abnormalities in testicular function can lead to infertility, hormonal imbalances, and other health problems. Regular self-examinations and medical check-ups are recommended for early detection and treatment of any potential issues.

Chromatids are defined as the individual strands that make up a duplicated chromosome. They are formed during the S phase of the cell cycle, when replication occurs and each chromosome is copied, resulting in two identical sister chromatids. These chromatids are connected at a region called the centromere and are held together by cohesin protein complexes until they are separated during mitosis or meiosis.

During mitosis, the sister chromatids are pulled apart by the mitotic spindle apparatus and distributed equally to each daughter cell. In meiosis, which is a type of cell division that occurs in the production of gametes (sex cells), homologous chromosomes pair up and exchange genetic material through a process called crossing over. After crossing over, each homologous chromosome consists of two recombinant chromatids that are separated during meiosis I, and then sister chromatids are separated during meiosis II.

Chromatids play an essential role in the faithful transmission of genetic information from one generation to the next, ensuring that each daughter cell or gamete receives a complete set of chromosomes with intact and functional genes.

The nuclear envelope is a complex and double-membrane structure that surrounds the eukaryotic cell's nucleus. It consists of two distinct membranes: the outer nuclear membrane, which is continuous with the endoplasmic reticulum (ER) membrane, and the inner nuclear membrane, which is closely associated with the chromatin and nuclear lamina.

The nuclear envelope serves as a selective barrier between the nucleus and the cytoplasm, controlling the exchange of materials and information between these two cellular compartments. Nuclear pore complexes (NPCs) are embedded in the nuclear envelope at sites where the inner and outer membranes fuse, forming aqueous channels that allow for the passive or active transport of molecules, such as ions, metabolites, and RNA-protein complexes.

The nuclear envelope plays essential roles in various cellular processes, including DNA replication, transcription, RNA processing, and chromosome organization. Additionally, it is dynamically regulated during the cell cycle, undergoing disassembly and reformation during mitosis to facilitate equal distribution of genetic material between daughter cells.

Anaphase is a stage in the cell division process called mitosis, where sister chromatids (the two copies of each chromosome formed during DNA replication) separate at the centromeres and move toward opposite poles of the cell. This separation is facilitated by the attachment of microtubules from the spindle apparatus to the kinetochores, protein structures located on the centromeres of each sister chromatid. Anaphase is followed by telophase, during which the nuclear membrane reforms around each set of separated chromosomes, and cytokinesis, the division of the cytoplasm to form two separate daughter cells.

Interphase is a phase in the cell cycle during which the cell primarily performs its functions of growth and DNA replication. It is the longest phase of the cell cycle, consisting of G1 phase (during which the cell grows and prepares for DNA replication), S phase (during which DNA replication occurs), and G2 phase (during which the cell grows further and prepares for mitosis). During interphase, the chromosomes are in their relaxed, extended form and are not visible under the microscope. Interphase is followed by mitosis, during which the chromosomes condense and separate to form two genetically identical daughter cells.

Nuclear proteins are a category of proteins that are primarily found in the nucleus of a eukaryotic cell. They play crucial roles in various nuclear functions, such as DNA replication, transcription, repair, and RNA processing. This group includes structural proteins like lamins, which form the nuclear lamina, and regulatory proteins, such as histones and transcription factors, that are involved in gene expression. Nuclear localization signals (NLS) often help target these proteins to the nucleus by interacting with importin proteins during active transport across the nuclear membrane.

Sex chromatin, also known as the Barr body, is an inactive X chromosome found in the nucleus of female cells. In females, one of the two X chromosomes is randomly inactivated during embryonic development to ensure that the dosage of X-linked genes is equivalent between males (who have one X chromosome) and females (who have two X chromosomes). The inactive X chromosome condenses and forms a compact structure called a sex chromatin body or Barr body, which can be observed during microscopic examination of cell nuclei. This phenomenon is known as X-inactivation and helps to prevent an overexpression of X-linked genes that could lead to developmental abnormalities.

Microtubules are hollow, cylindrical structures composed of tubulin proteins in the cytoskeleton of eukaryotic cells. They play crucial roles in various cellular processes such as maintaining cell shape, intracellular transport, and cell division (mitosis and meiosis). Microtubules are dynamic, undergoing continuous assembly and disassembly, which allows them to rapidly reorganize in response to cellular needs. They also form part of important cellular structures like centrioles, basal bodies, and cilia/flagella.

Chromosomes in fungi are thread-like structures that contain genetic material, composed of DNA and proteins, present in the nucleus of a cell. Unlike humans and other eukaryotes that have a diploid number of chromosomes in their somatic cells, fungal chromosome numbers can vary widely between and within species.

Fungal chromosomes are typically smaller and fewer in number compared to those found in plants and animals. The chromosomal organization in fungi is also different from other eukaryotes. In many fungi, the chromosomes are condensed throughout the cell cycle, whereas in other eukaryotes, chromosomes are only condensed during cell division.

Fungi can have linear or circular chromosomes, depending on the species. For example, the model organism Saccharomyces cerevisiae (budding yeast) has a set of 16 small circular chromosomes, while other fungi like Neurospora crassa (red bread mold) and Aspergillus nidulans (a filamentous fungus) have linear chromosomes.

Fungal chromosomes play an essential role in the growth, development, reproduction, and survival of fungi. They carry genetic information that determines various traits such as morphology, metabolism, pathogenicity, and resistance to environmental stresses. Advances in genomic technologies have facilitated the study of fungal chromosomes, leading to a better understanding of their structure, function, and evolution.

A centrosome is a microtubule-organizing center found in animal cells. It consists of two barrel-shaped structures called centrioles, which are surrounded by a protein matrix called the pericentriolar material. The centrosome plays a crucial role in organizing the microtubules that form the cell's cytoskeleton and help to shape the cell, as well as in separating the chromosomes during cell division.

During mitosis, the two centrioles of the centrosome separate and move to opposite poles of the cell, where they nucleate the formation of the spindle fibers that pull the chromosomes apart. The centrosome also helps to ensure that the genetic material is equally distributed between the two resulting daughter cells.

It's worth noting that while centrioles are present in many animal cells, they are not always present in all types of cells. For example, plant cells do not have centrioles or centrosomes, and instead rely on other mechanisms to organize their microtubules.

CDC2 protein kinase, also known as cell division cycle 2 or CDK1, is a type of enzyme that plays a crucial role in the regulation of the cell cycle. The cell cycle is the series of events that cells undergo as they grow, replicate their DNA, and divide into two daughter cells.

CDC2 protein kinase is a member of the cyclin-dependent kinase (CDK) family, which are serine/threonine protein kinases that are activated by binding to regulatory subunits called cyclins. CDC2 protein kinase is primarily associated with the regulation of the G2 phase and the entry into mitosis, the stage of the cell cycle where nuclear and cytoplasmic division occur.

CDC2 protein kinase functions by phosphorylating various target proteins, which alters their activity and contributes to the coordination of the different events that occur during the cell cycle. The activity of CDC2 protein kinase is tightly regulated through a variety of mechanisms, including phosphorylation and dephosphorylation, as well as the binding and destruction of cyclin subunits.

Dysregulation of CDC2 protein kinase has been implicated in various human diseases, including cancer, where uncontrolled cell division can lead to the formation of tumors. Therefore, understanding the regulation and function of CDC2 protein kinase is an important area of research in molecular biology and medicine.

Germ cells are the reproductive cells, also known as sex cells, that combine to form offspring in sexual reproduction. In females, germ cells are called ova or egg cells, and in males, they are called spermatozoa or sperm cells. These cells are unique because they carry half the genetic material necessary for creating new life. They are produced through a process called meiosis, which reduces their chromosome number by half, ensuring that when two germ cells combine during fertilization, the normal diploid number of chromosomes is restored.

Cyclin B is a type of cyclin protein that regulates the cell cycle, specifically the transition from G2 phase to mitosis (M phase) in eukaryotic cells. Cyclin B binds and activates cyclin-dependent kinase 1 (CDK1), forming the complex known as M-phase promoting factor (MPF). This complex triggers the events leading to cell division, such as chromosome condensation, nuclear envelope breakdown, and spindle formation. The levels of cyclin B increase during the G2 phase and are degraded by the anaphase-promoting complex/cyclosome (APC/C) at the onset of anaphase, allowing the cell cycle to progress into the next phase.

Genetic recombination is the process by which genetic material is exchanged between two similar or identical molecules of DNA during meiosis, resulting in new combinations of genes on each chromosome. This exchange occurs during crossover, where segments of DNA are swapped between non-sister homologous chromatids, creating genetic diversity among the offspring. It is a crucial mechanism for generating genetic variability and facilitating evolutionary change within populations. Additionally, recombination also plays an essential role in DNA repair processes through mechanisms such as homologous recombinational repair (HRR) and non-homologous end joining (NHEJ).

Rad51 recombinase is a protein involved in the repair of double-stranded DNA breaks through homologous recombination, a process that helps maintain genomic stability. This protein forms a nucleoprotein filament on single-stranded DNA, facilitating the search for and invasion of homologous sequences in double-stranded DNA. Rad51 recombinase is highly conserved across various species, including humans, and plays a crucial role in preventing genetic disorders, cancer, and aging caused by DNA damage.

The cell cycle is a series of events that take place in a cell leading to its division and duplication. It consists of four main phases: G1 phase, S phase, G2 phase, and M phase.

During the G1 phase, the cell grows in size and synthesizes mRNA and proteins in preparation for DNA replication. In the S phase, the cell's DNA is copied, resulting in two complete sets of chromosomes. During the G2 phase, the cell continues to grow and produces more proteins and organelles necessary for cell division.

The M phase is the final stage of the cell cycle and consists of mitosis (nuclear division) and cytokinesis (cytoplasmic division). Mitosis results in two genetically identical daughter nuclei, while cytokinesis divides the cytoplasm and creates two separate daughter cells.

The cell cycle is regulated by various checkpoints that ensure the proper completion of each phase before progressing to the next. These checkpoints help prevent errors in DNA replication and division, which can lead to mutations and cancer.

'Caenorhabditis elegans' is a species of free-living, transparent nematode (roundworm) that is widely used as a model organism in scientific research, particularly in the fields of biology and genetics. It has a simple anatomy, short lifespan, and fully sequenced genome, making it an ideal subject for studying various biological processes and diseases.

Some notable features of C. elegans include:

* Small size: Adult hermaphrodites are about 1 mm in length.
* Short lifespan: The average lifespan of C. elegans is around 2-3 weeks, although some strains can live up to 4 weeks under laboratory conditions.
* Development: C. elegans has a well-characterized developmental process, with adults developing from eggs in just 3 days at 20°C.
* Transparency: The transparent body of C. elegans allows researchers to observe its internal structures and processes easily.
* Genetics: C. elegans has a fully sequenced genome, which contains approximately 20,000 genes. Many of these genes have human homologs, making it an excellent model for studying human diseases.
* Neurobiology: C. elegans has a simple nervous system, with only 302 neurons in the hermaphrodite and 383 in the male. This simplicity makes it an ideal organism for studying neural development, function, and behavior.

Research using C. elegans has contributed significantly to our understanding of various biological processes, including cell division, apoptosis, aging, learning, and memory. Additionally, studies on C. elegans have led to the discovery of many genes associated with human diseases such as cancer, neurodegenerative disorders, and metabolic conditions.

'Caenorhabditis elegans' (C. elegans) is a type of free-living, transparent nematode (roundworm) that is often used as a model organism in scientific research. C. elegans proteins refer to the various types of protein molecules that are produced by the organism's genes and play crucial roles in maintaining its biological functions.

Proteins are complex molecules made up of long chains of amino acids, and they are involved in virtually every cellular process, including metabolism, DNA replication, signal transduction, and transportation of molecules within the cell. In C. elegans, proteins are encoded by genes, which are transcribed into messenger RNA (mRNA) molecules that are then translated into protein sequences by ribosomes.

Studying C. elegans proteins is important for understanding the basic biology of this organism and can provide insights into more complex biological systems, including humans. Because C. elegans has a relatively simple nervous system and a short lifespan, it is often used to study neurobiology, aging, and development. Additionally, because many of the genes and proteins in C. elegans have counterparts in other organisms, including humans, studying them can provide insights into human disease processes and potential therapeutic targets.

Cyclin B1 is a type of cyclin protein that regulates the cell cycle, specifically the transition from G2 phase to mitosis (M phase) in eukaryotic cells. It forms a complex with and acts as a regulatory subunit of cyclin-dependent kinase 1 (CDK1), also known as CDC2. During the G2 phase, Cyclin B1 levels accumulate and upon reaching a certain threshold, it binds to CDK1 to form the maturation promoting factor (MPF). The activation of MPF triggers the onset of mitosis by promoting nuclear envelope breakdown, chromosome condensation, and other events required for cell division. After the completion of mitosis, Cyclin B1 is degraded by the ubiquitin-proteasome system, allowing the cell cycle to progress back into G1 phase.

The nucleolus is a structure found within the nucleus of eukaryotic cells (cells that contain a true nucleus). It plays a central role in the production and assembly of ribosomes, which are complex molecular machines responsible for protein synthesis. The nucleolus is not a distinct organelle with a membrane surrounding it, but rather a condensed region within the nucleus where ribosomal biogenesis takes place.

The process of ribosome formation begins in the nucleolus with the transcription of ribosomal DNA (rDNA) genes into long precursor RNA molecules called rRNAs (ribosomal RNAs). Within the nucleolus, these rRNA molecules are cleaved, modified, and assembled together with ribosomal proteins to form small and large ribosomal subunits. Once formed, these subunits are transported through the nuclear pores to the cytoplasm, where they come together to form functional ribosomes that can engage in protein synthesis.

In addition to its role in ribosome biogenesis, the nucleolus has been implicated in other cellular processes such as stress response, cell cycle regulation, and aging. Changes in nucleolar structure and function have been associated with various diseases, including cancer and neurodegenerative disorders.

An ovary is a part of the female reproductive system in which ova or eggs are produced through the process of oogenesis. They are a pair of solid, almond-shaped structures located one on each side of the uterus within the pelvic cavity. Each ovary measures about 3 to 5 centimeters in length and weighs around 14 grams.

The ovaries have two main functions: endocrine (hormonal) function and reproductive function. They produce and release eggs (ovulation) responsible for potential fertilization and development of an embryo/fetus during pregnancy. Additionally, they are essential in the production of female sex hormones, primarily estrogen and progesterone, which regulate menstrual cycles, sexual development, and reproduction.

During each menstrual cycle, a mature egg is released from one of the ovaries into the fallopian tube, where it may be fertilized by sperm. If not fertilized, the egg, along with the uterine lining, will be shed, leading to menstruation.

Sex chromosomes, often denoted as X and Y, are one of the 23 pairs of human chromosomes found in each cell of the body. Normally, females have two X chromosomes (46,XX), and males have one X and one Y chromosome (46,XY). The sex chromosomes play a significant role in determining the sex of an individual. They contain genes that contribute to physical differences between men and women. Any variations or abnormalities in the number or structure of these chromosomes can lead to various genetic disorders and conditions related to sexual development and reproduction.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

"Coprinus" is a genus of fungi in the family Agaricaceae. It includes several species commonly known as "ink caps" or "shaggy manes." These mushrooms are characterized by their slimy, shaggy caps and the dark ink-like liquid that oozes from the gills when they mature. Some species of Coprinus are edible and considered delicacies, while others can cause adverse reactions if consumed with alcohol. It's important to note that proper identification is necessary before consuming any wild mushrooms.

Protein-Serine-Threonine Kinases (PSTKs) are a type of protein kinase that catalyzes the transfer of a phosphate group from ATP to the hydroxyl side chains of serine or threonine residues on target proteins. This phosphorylation process plays a crucial role in various cellular signaling pathways, including regulation of metabolism, gene expression, cell cycle progression, and apoptosis. PSTKs are involved in many physiological and pathological processes, and their dysregulation has been implicated in several diseases, such as cancer, diabetes, and neurodegenerative disorders.

Aurora kinases are a family of serine/threonine protein kinases that play crucial roles in the regulation of cell division. There are three members of the Aurora kinase family, designated as Aurora A, Aurora B, and Aurora C. These kinases are involved in the proper separation of chromosomes during mitosis and meiosis, and their dysregulation has been implicated in various types of cancer.

Aurora A is primarily located at the centrosomes and spindle poles during cell division, where it regulates centrosome maturation, bipolar spindle formation, and chromosome segregation. Aurora B, on the other hand, is a component of the chromosomal passenger complex (CPC) that localizes to the centromeres during prophase and moves to the spindle midzone during anaphase. It plays essential roles in kinetochore-microtubule attachment, chromosome alignment, and cytokinesis. Aurora C is most similar to Aurora B and appears to have overlapping functions with it, although its specific roles are less well understood.

Dysregulation of Aurora kinases has been associated with various types of cancer, including breast, ovarian, colon, and lung cancers. Overexpression or amplification of Aurora A is observed in many cancers, leading to chromosomal instability and aneuploidy. Inhibition of Aurora kinases has emerged as a potential therapeutic strategy for cancer treatment, with several small molecule inhibitors currently under investigation in clinical trials.

A telomere is a region of repetitive DNA sequences found at the end of chromosomes, which protects the genetic data from damage and degradation during cell division. Telomeres naturally shorten as cells divide, and when they become too short, the cell can no longer divide and becomes senescent or dies. This natural process is associated with aging and various age-related diseases. The length of telomeres can also be influenced by various genetic and environmental factors, including stress, diet, and lifestyle.

The G2 phase, also known as the "gap 2 phase," is a stage in the cell cycle that occurs after DNA replication (S phase) and before cell division (mitosis). During this phase, the cell prepares for mitosis by completing the synthesis of proteins and organelles needed for chromosome separation. The cell also checks for any errors or damage to the DNA before entering mitosis. This phase is a critical point in the cell cycle where proper regulation ensures the faithful transmission of genetic information from one generation of cells to the next. If significant DNA damage is detected during G2, the cell may undergo programmed cell death (apoptosis) instead of dividing.

Chromatin is the complex of DNA, RNA, and proteins that make up the chromosomes in the nucleus of a cell. It is responsible for packaging the long DNA molecules into a more compact form that fits within the nucleus. Chromatin is made up of repeating units called nucleosomes, which consist of a histone protein octamer wrapped tightly by DNA. The structure of chromatin can be altered through chemical modifications to the histone proteins and DNA, which can influence gene expression and other cellular processes.

The Y chromosome is one of the two sex-determining chromosomes in humans and many other animals, along with the X chromosome. The Y chromosome contains the genetic information that helps to determine an individual's sex as male. It is significantly smaller than the X chromosome and contains fewer genes.

The Y chromosome is present in males, who inherit it from their father. Females, on the other hand, have two X chromosomes, one inherited from each parent. The Y chromosome includes a gene called SRY (sex-determining region Y), which initiates the development of male sexual characteristics during embryonic development.

It is worth noting that the Y chromosome has a relatively high rate of genetic mutation and degeneration compared to other chromosomes, leading to concerns about its long-term viability in human evolution. However, current evidence suggests that the Y chromosome has been stable for at least the past 25 million years.

I apologize for any confusion, but "Schizosaccharomyces" is not a medical term. It is a genus name in the field of microbiology and genetics, referring to a group of budding, tear-shaped yeasts that are widely used as model organisms in scientific research. The most well-known species within this genus is Schizosaccharomyces pombe, which has been extensively studied for its cell cycle regulation, DNA repair mechanisms, and other fundamental biological processes.

If you have any questions related to medical terminology or health-related topics, I would be happy to help.

Tubulin is a type of protein that forms microtubules, which are hollow cylindrical structures involved in the cell's cytoskeleton. These structures play important roles in various cellular processes, including maintaining cell shape, cell division, and intracellular transport. There are two main types of tubulin proteins: alpha-tubulin and beta-tubulin. They polymerize to form heterodimers, which then assemble into microtubules. The assembly and disassembly of microtubules are dynamic processes that are regulated by various factors, including GTP hydrolysis, motor proteins, and microtubule-associated proteins (MAPs). Tubulin is an essential component of the eukaryotic cell and has been a target for anti-cancer drugs such as taxanes and vinca alkaloids.

Fluorescence microscopy is a type of microscopy that uses fluorescent dyes or proteins to highlight and visualize specific components within a sample. In this technique, the sample is illuminated with high-energy light, typically ultraviolet (UV) or blue light, which excites the fluorescent molecules causing them to emit lower-energy, longer-wavelength light, usually visible light in the form of various colors. This emitted light is then collected by the microscope and detected to produce an image.

Fluorescence microscopy has several advantages over traditional brightfield microscopy, including the ability to visualize specific structures or molecules within a complex sample, increased sensitivity, and the potential for quantitative analysis. It is widely used in various fields of biology and medicine, such as cell biology, neuroscience, and pathology, to study the structure, function, and interactions of cells and proteins.

There are several types of fluorescence microscopy techniques, including widefield fluorescence microscopy, confocal microscopy, two-photon microscopy, and total internal reflection fluorescence (TIRF) microscopy, each with its own strengths and limitations. These techniques can provide valuable insights into the behavior of cells and proteins in health and disease.

Dyneins are a type of motor protein that play an essential role in the movement of cellular components and structures within eukaryotic cells. They are responsible for generating force and motion along microtubules, which are critical components of the cell's cytoskeleton. Dyneins are involved in various cellular processes, including intracellular transport, organelle positioning, and cell division.

There are several types of dyneins, but the two main categories are cytoplasmic dyneins and axonemal dyneins. Cytoplasmic dyneins are responsible for moving various cargoes, such as vesicles, organelles, and mRNA complexes, toward the minus-end of microtubules, which is usually located near the cell center. Axonemal dyneins, on the other hand, are found in cilia and flagella and are responsible for their movement by sliding adjacent microtubules past each other.

Dyneins consist of multiple subunits, including heavy chains, intermediate chains, light-intermediate chains, and light chains. The heavy chains contain the motor domain that binds to microtubules and hydrolyzes ATP to generate force. Dysfunction in dynein proteins has been linked to various human diseases, such as neurodevelopmental disorders, ciliopathies, and cancer.

Aurora Kinase B is a type of enzyme that plays a crucial role in the regulation of cell division and mitosis. It is a member of the Aurora kinase family, which includes three different isoforms (Aurora A, B, and C). Among these, Aurora Kinase B is specifically involved in the proper alignment and separation of chromosomes during cell division.

During mitosis, Aurora Kinase B forms a complex with other proteins to form the chromosomal passenger complex (CPC), which plays a critical role in ensuring accurate chromosome segregation. The CPC is responsible for regulating various events during mitosis, including the attachment of microtubules to kinetochores (protein structures that connect chromosomes to spindle fibers), the correction of erroneous kinetochore-microtubule attachments, and the regulation of the anaphase promoting complex/cyclosome (APC/C), which targets specific proteins for degradation during mitosis.

Dysregulation of Aurora Kinase B has been implicated in various human diseases, including cancer. Overexpression or amplification of this kinase can lead to chromosomal instability and aneuploidy, contributing to tumorigenesis and cancer progression. As a result, Aurora Kinase B is considered a promising target for the development of anti-cancer therapies, with several inhibitors currently being investigated in preclinical and clinical studies.

Histones are highly alkaline proteins found in the chromatin of eukaryotic cells. They are rich in basic amino acid residues, such as arginine and lysine, which give them their positive charge. Histones play a crucial role in packaging DNA into a more compact structure within the nucleus by forming a complex with it called a nucleosome. Each nucleosome contains about 146 base pairs of DNA wrapped around an octamer of eight histone proteins (two each of H2A, H2B, H3, and H4). The N-terminal tails of these histones are subject to various post-translational modifications, such as methylation, acetylation, and phosphorylation, which can influence chromatin structure and gene expression. Histone variants also exist, which can contribute to the regulation of specific genes and other nuclear processes.

Kinetochores are specialized protein structures that form on the centromere region of a chromosome. They play a crucial role in the process of cell division, specifically during mitosis and meiosis. The primary function of kinetochores is to connect the chromosomes to the microtubules of the spindle apparatus, which is responsible for separating the sister chromatids during cell division. Through this connection, kinetochores facilitate the movement of chromosomes towards opposite poles of the cell during anaphase, ensuring equal distribution of genetic material to each resulting daughter cell.

Organoids are 3D tissue cultures grown from stem cells that mimic the structure and function of specific organs. They are used in research to study development, disease, and potential treatments. The term "organoid" refers to the fact that these cultures can organize themselves into structures that resemble rudimentary organs, with differentiated cell types arranged in a pattern similar to their counterparts in the body. Organoids can be derived from various sources, including embryonic stem cells, induced pluripotent stem cells (iPSCs), or adult stem cells, and they provide a valuable tool for studying complex biological processes in a controlled laboratory setting.

HeLa cells are a type of immortalized cell line used in scientific research. They are derived from a cancer that developed in the cervical tissue of Henrietta Lacks, an African-American woman, in 1951. After her death, cells taken from her tumor were found to be capable of continuous division and growth in a laboratory setting, making them an invaluable resource for medical research.

HeLa cells have been used in a wide range of scientific studies, including research on cancer, viruses, genetics, and drug development. They were the first human cell line to be successfully cloned and are able to grow rapidly in culture, doubling their population every 20-24 hours. This has made them an essential tool for many areas of biomedical research.

It is important to note that while HeLa cells have been instrumental in numerous scientific breakthroughs, the story of their origin raises ethical questions about informed consent and the use of human tissue in research.

Double-stranded DNA breaks (DSBs) refer to a type of damage that occurs in the DNA molecule when both strands of the double helix are severed or broken at the same location. This kind of damage is particularly harmful to cells because it can disrupt the integrity and continuity of the genetic material, potentially leading to genomic instability, mutations, and cell death if not properly repaired.

DSBs can arise from various sources, including exposure to ionizing radiation, chemical agents, free radicals, reactive oxygen species (ROS), and errors during DNA replication or repair processes. Unrepaired or incorrectly repaired DSBs have been implicated in numerous human diseases, such as cancer, neurodegenerative disorders, and premature aging.

Cells possess several mechanisms to repair double-stranded DNA breaks, including homologous recombination (HR) and non-homologous end joining (NHEJ). HR is a more accurate repair pathway that uses a homologous template, typically the sister chromatid, to restore the original DNA sequence. NHEJ, on the other hand, directly ligates the broken ends together, often resulting in small deletions or insertions at the break site and increased risk of errors. The choice between these two pathways depends on various factors, such as the cell cycle stage, the presence of nearby breaks, and the availability of repair proteins.

In summary, double-stranded DNA breaks are severe forms of DNA damage that can have detrimental consequences for cells if not properly repaired. Cells employ multiple mechanisms to address DSBs, with homologous recombination and non-homologous end joining being the primary repair pathways.

Endodeoxyribonucleases are a type of enzyme that cleave, or cut, phosphodiester bonds within the backbone of DNA molecules. These enzymes are also known as restriction endonucleases or simply restriction enzymes. They are called "restriction" enzymes because they were first discovered in bacteria, where they function to protect the organism from foreign DNA by cleaving and destroying invading viral DNA.

Endodeoxyribonucleases recognize specific sequences of nucleotides within the DNA molecule, known as recognition sites or restriction sites, and cut the phosphodiester bonds at specific locations within these sites. The cuts made by endodeoxyribonucleases can be either "sticky" or "blunt," depending on whether the enzyme leaves single-stranded overhangs or creates blunt ends at the site of cleavage, respectively.

Endodeoxyribonucleases are widely used in molecular biology research for various applications, including DNA cloning, genome mapping, and genetic engineering. They allow researchers to cut DNA molecules at specific sites, creating defined fragments that can be manipulated and recombined in a variety of ways.

Cdh1 proteins are part of the anaphase-promoting complex/cyclosome (APC/C), which is a multi-subunit E3 ubiquitin ligase that plays a critical role in regulating the cell cycle. Cdh1, specifically, is a regulatory subunit of the APC/C and is essential for the proper progression through the cell cycle.

Cdh1 binds to and activates the APC/C in late mitosis and early G1 phase, targeting specific proteins for ubiquitination and subsequent degradation by the proteasome. This helps to ensure that key events of the cell cycle, such as chromosome segregation and mitotic exit, occur in a timely and orderly fashion.

Cdh1 has been shown to regulate the degradation of several important cell cycle regulators, including cyclins A and B, securin, and aurora kinase A. By targeting these proteins for destruction, Cdh1 helps to prevent premature entry into mitosis and ensures that cells do not exit mitosis until all chromosomes have been properly aligned and segregated.

Mutations in the genes encoding Cdh1 and other components of the APC/C have been implicated in a variety of human cancers, highlighting the importance of this complex in maintaining genomic stability.

The Anaphase-Promoting Complex/Cyclosome (APC/C) is a large E3 ubiquitin ligase complex that plays a crucial role in the regulation of the cell cycle. It is responsible for targeting specific proteins for degradation by the proteasome, which is a multi-subunit protein complex that mediates the controlled breakdown of ubiquitinated proteins.

During anaphase, the final stage of mitosis, the APC/C becomes active and triggers the degradation of several key regulatory proteins, including securin and cyclin B. The destruction of these proteins allows for the separation of chromosomes and the completion of cell division.

The APC/C is composed of multiple subunits, including a catalytic core that binds to ubiquitin-conjugating enzymes (E2s) and several coactivators that regulate its activity. The activation of the APC/C requires the binding of one of two coactivators, Cdc20 or CDH1, which recognize specific substrates for degradation.

Dysregulation of the APC/C has been implicated in various human diseases, including cancer and neurodegenerative disorders. Therefore, understanding the mechanisms that regulate its activity is an important area of research with potential therapeutic implications.

Gametogenesis is the biological process by which haploid gametes, or sex cells (sperm and egg cells), are produced through the meiotic division of diploid germ cells. In females, this process is called oogenesis, where an oogonium (diploid germ cell) undergoes mitosis to form an oocyte (immature egg cell). The oocyte then undergoes meiosis I to form a secondary oocyte and a polar body. After fertilization by a sperm cell, the secondary oocyte completes meiosis II to form a mature ovum or egg cell.

In males, this process is called spermatogenesis, where a spermatogonium (diploid germ cell) undergoes mitosis to form primary spermatocytes. Each primary spermatocyte then undergoes meiosis I to form two secondary spermatocytes, which subsequently undergo meiosis II to form four haploid spermatids. The spermatids then differentiate into spermatozoa or sperm cells through a process called spermiogenesis.

Gametogenesis is essential for sexual reproduction and genetic diversity, as it involves the random segregation of chromosomes during meiosis and the recombination of genetic material between homologous chromosomes.

Nondisjunction is a genetic term that refers to the failure of homologous chromosomes or sister chromatids to properly separate during cell division, resulting in an abnormal number of chromosomes in the daughter cells. This can occur during either mitosis (resulting in somatic mutations) or meiosis (leading to gametes with an incorrect number of chromosomes).

In humans, nondisjunction of chromosome 21 during meiosis is the most common cause of Down syndrome, resulting in three copies of chromosome 21 (trisomy 21) in the affected individual. Nondisjunction can also result in other aneuploidies, such as Turner syndrome (X monosomy), Klinefelter syndrome (XXY), and Edwards syndrome (trisomy 18).

Nondisjunction is typically a random event, although maternal age has been identified as a risk factor for nondisjunction during meiosis. In some cases, structural chromosomal abnormalities or genetic factors may predispose an individual to nondisjunction events.

I believe you may be mistakenly using the term "starfish" to refer to a medical condition. If so, the correct term is likely " asterixis," which is a medical sign characterized by rapid, rhythmic flapping or tremulous movements of the hands when they are extended and the wrist is dorsiflexed (held with the back of the hand facing upwards). This is often seen in people with certain neurological conditions such as liver failure or certain types of poisoning.

However, if you are indeed referring to the marine animal commonly known as a "starfish," there isn't a specific medical definition for it. Starfish, also known as sea stars, are marine animals belonging to the class Asteroidea in the phylum Echinodermata. They have a distinctive shape with five or more arms radiating from a central disc, and they move slowly along the ocean floor using their tube feet. Some species of starfish have the ability to regenerate lost body parts, including entire limbs or even their central disc.

In situ hybridization, fluorescence (FISH) is a type of molecular cytogenetic technique used to detect and localize the presence or absence of specific DNA sequences on chromosomes through the use of fluorescent probes. This technique allows for the direct visualization of genetic material at a cellular level, making it possible to identify chromosomal abnormalities such as deletions, duplications, translocations, and other rearrangements.

The process involves denaturing the DNA in the sample to separate the double-stranded molecules into single strands, then adding fluorescently labeled probes that are complementary to the target DNA sequence. The probe hybridizes to the complementary sequence in the sample, and the location of the probe is detected by fluorescence microscopy.

FISH has a wide range of applications in both clinical and research settings, including prenatal diagnosis, cancer diagnosis and monitoring, and the study of gene expression and regulation. It is a powerful tool for identifying genetic abnormalities and understanding their role in human disease.

Nocodazole is not a medical condition or disease, but rather a pharmacological agent used in medical research and clinical settings. It's a synthetic chemical compound that belongs to the class of drugs known as microtubule inhibitors. Nocodazole works by binding to and disrupting the dynamic assembly and disassembly of microtubules, which are important components of the cell's cytoskeleton and play a critical role in cell division.

Nocodazole is primarily used in research settings as a tool for studying cell biology and mitosis, the process by which cells divide. It can be used to synchronize cells in the cell cycle or to induce mitotic arrest, making it useful for investigating various aspects of cell division and chromosome behavior.

In clinical settings, nocodazole has been used off-label as a component of some cancer treatment regimens, particularly in combination with other chemotherapeutic agents. Its ability to disrupt microtubules can interfere with the proliferation of cancer cells and enhance the effectiveness of certain anti-cancer drugs. However, its use is not widespread due to potential side effects and the availability of alternative treatments.

Fungal spores are defined as the reproductive units of fungi that are produced by specialized structures called hyphae. These spores are typically single-celled and can exist in various shapes such as round, oval, or ellipsoidal. They are highly resistant to extreme environmental conditions like heat, cold, and dryness, which allows them to survive for long periods until they find a suitable environment to germinate and grow into a new fungal organism. Fungal spores can be found in the air, water, soil, and on various surfaces, making them easily dispersible and capable of causing infections in humans, animals, and plants.

Ubiquitin-Protein Ligase Complexes, also known as E3 ubiquitin ligases, are a group of enzymes that play a crucial role in the ubiquitination process. Ubiquitination is a post-translational modification where ubiquitin molecules are attached to specific target proteins, marking them for degradation by the proteasome or altering their function, localization, or interaction with other proteins.

The ubiquitination process involves three main steps:

1. Ubiquitin activation: Ubiquitin is activated by an E1 ubiquitin-activating enzyme in an ATP-dependent reaction.
2. Ubiquitin conjugation: The activated ubiquitin is then transferred to an E2 ubiquitin-conjugating enzyme.
3. Ubiquitin ligation: Finally, the E2 ubiquitin-conjugating enzyme interacts with a specific E3 ubiquitin ligase complex, which facilitates the transfer and ligation of ubiquitin to the target protein.

Ubiquitin-Protein Ligase Complexes are responsible for recognizing and binding to specific substrate proteins, ensuring that ubiquitination occurs on the correct targets. They can be divided into three main categories based on their structural features and mechanisms of action:

1. Really Interesting New Gene (RING) finger E3 ligases: These E3 ligases contain a RING finger domain, which directly interacts with both the E2 ubiquitin-conjugating enzyme and the substrate protein. They facilitate the transfer of ubiquitin from the E2 to the target protein by bringing them into close proximity.
2. Homologous to E6-AP C terminus (HECT) E3 ligases: These E3 ligases contain a HECT domain, which interacts with the E2 ubiquitin-conjugating enzyme and forms a thioester bond with ubiquitin before transferring it to the substrate protein.
3. RING-between-RING (RBR) E3 ligases: These E3 ligases contain both RING finger and HECT-like domains, which allow them to function similarly to both RING finger and HECT E3 ligases. They first form a thioester bond with ubiquitin using their RING1 domain before transferring it to the substrate protein via their RING2 domain.

Dysregulation of Ubiquitin-Protein Ligase Complexes has been implicated in various diseases, including cancer and neurodegenerative disorders. Understanding their mechanisms and functions can provide valuable insights into disease pathogenesis and potential therapeutic strategies.

The X chromosome is one of the two types of sex-determining chromosomes in humans (the other being the Y chromosome). It's one of the 23 pairs of chromosomes that make up a person's genetic material. Females typically have two copies of the X chromosome (XX), while males usually have one X and one Y chromosome (XY).

The X chromosome contains hundreds of genes that are responsible for the production of various proteins, many of which are essential for normal bodily functions. Some of the critical roles of the X chromosome include:

1. Sex Determination: The presence or absence of the Y chromosome determines whether an individual is male or female. If there is no Y chromosome, the individual will typically develop as a female.
2. Genetic Disorders: Since females have two copies of the X chromosome, they are less likely to be affected by X-linked genetic disorders than males. Males, having only one X chromosome, will express any recessive X-linked traits they inherit.
3. Dosage Compensation: To compensate for the difference in gene dosage between males and females, a process called X-inactivation occurs during female embryonic development. One of the two X chromosomes is randomly inactivated in each cell, resulting in a single functional copy per cell.

The X chromosome plays a crucial role in human genetics and development, contributing to various traits and characteristics, including sex determination and dosage compensation.

CDC25 phosphatases are a group of enzymes that play crucial roles in the regulation of the cell cycle, which is the series of events that cells undergo as they grow and divide. Specifically, CDC25 phosphatases function to remove inhibitory phosphates from certain cyclin-dependent kinases (CDKs), thereby activating them and allowing the cell cycle to progress.

There are three main types of CDC25 phosphatases in humans, known as CDC25A, CDC25B, and CDC25C. These enzymes are named after the original yeast homolog, called Cdc25, which was discovered to be essential for cell cycle progression.

CDC25 phosphatases are tightly regulated during the cell cycle, with their activity being controlled by various mechanisms such as phosphorylation, protein-protein interactions, and subcellular localization. Dysregulation of CDC25 phosphatases has been implicated in several human diseases, including cancer, where they can contribute to uncontrolled cell growth and division. Therefore, understanding the functions and regulation of CDC25 phosphatases is an important area of research in molecular biology and medicine.

The Fluorescent Antibody Technique (FAT) is a type of immunofluorescence assay used in laboratory medicine and pathology for the detection and localization of specific antigens or antibodies in tissues, cells, or microorganisms. In this technique, a fluorescein-labeled antibody is used to selectively bind to the target antigen or antibody, forming an immune complex. When excited by light of a specific wavelength, the fluorescein label emits light at a longer wavelength, typically visualized as green fluorescence under a fluorescence microscope.

The FAT is widely used in diagnostic microbiology for the identification and characterization of various bacteria, viruses, fungi, and parasites. It has also been applied in the diagnosis of autoimmune diseases and certain cancers by detecting specific antibodies or antigens in patient samples. The main advantage of FAT is its high sensitivity and specificity, allowing for accurate detection and differentiation of various pathogens and disease markers. However, it requires specialized equipment and trained personnel to perform and interpret the results.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Cyclin A1 is a type of cyclin protein that regulates the cell cycle, particularly during the S and G2 phases. It forms a complex with and acts as a regulatory subunit of cyclin-dependent kinase 2 (CDK2), helping to control the transition from the G1 phase to the S phase and from the S phase to the G2 phase. Cyclin A1 is expressed in various tissues, including ovary, testis, bone marrow, and lymphoid cells. Overexpression or dysregulation of cyclin A1 has been implicated in several types of cancer, making it a potential target for cancer therapy.

Disorders of Sex Development (DSD) are a group of conditions that occur when there is a difference in the development and assignment of sex characteristics. These differences may be apparent at birth, at puberty, or later in life. DSD can affect chromosomes, gonads, genitals, or secondary sexual characteristics, and can result from genetic mutations or environmental factors during fetal development.

DSDs were previously referred to as "intersex" conditions, but the term "Disorders of Sex Development" is now preferred in medical settings because it is more descriptive and less stigmatizing. DSDs are not errors or abnormalities, but rather variations in human development that require sensitive and individualized care.

The diagnosis and management of DSD can be complex and may involve a team of healthcare providers, including endocrinologists, urologists, gynecologists, psychologists, and genetic counselors. Treatment options depend on the specific type of DSD and may include hormone therapy, surgery, or other interventions to support physical and emotional well-being.

Maturation-Promoting Factor (MPF) is not a medical term per se, but it is commonly used in the field of cell biology and cancer research. MPF refers to a complex of two proteins that play a crucial role in regulating the cell cycle, specifically during the transition from the G2 phase to mitosis (M phase).

MPF is composed of a cyclin-dependent kinase (CDK1) and a regulatory subunit called cyclin B. During the late G2 phase, the levels of cyclin B increase, which leads to the activation of CDK1. Once activated, MPF triggers a series of events that promote mitosis, including chromosome condensation, nuclear envelope breakdown, and spindle formation.

In summary, Maturation-Promoting Factor (MPF) is a protein complex made up of CDK1 and cyclin B, which regulates the transition from the G2 phase to mitosis during the cell cycle.

Saccharomyces cerevisiae proteins are the proteins that are produced by the budding yeast, Saccharomyces cerevisiae. This organism is a single-celled eukaryote that has been widely used as a model organism in scientific research for many years due to its relatively simple genetic makeup and its similarity to higher eukaryotic cells.

The genome of Saccharomyces cerevisiae has been fully sequenced, and it is estimated to contain approximately 6,000 genes that encode proteins. These proteins play a wide variety of roles in the cell, including catalyzing metabolic reactions, regulating gene expression, maintaining the structure of the cell, and responding to environmental stimuli.

Many Saccharomyces cerevisiae proteins have human homologs and are involved in similar biological processes, making this organism a valuable tool for studying human disease. For example, many of the proteins involved in DNA replication, repair, and recombination in yeast have human counterparts that are associated with cancer and other diseases. By studying these proteins in yeast, researchers can gain insights into their function and regulation in humans, which may lead to new treatments for disease.

I'm sorry for any confusion, but "Schizosaccharomyces pombe proteins" is not a medical term or concept. Schizosaccharomyces pombe is a type of single-celled microorganism called a yeast, which is often used as a model organism in scientific research. Proteins are complex molecules that do most of the work in cells and are necessary for the structure, function, and regulation of the body's tissues and organs.

In the context of scientific research, "Schizosaccharomyces pombe proteins" would refer to the specific proteins found in or studied using this particular type of yeast. These proteins may have similarities to human proteins and can be used to help understand basic biological processes, as well as diseases that occur in humans. However, it is important to note that while research using model organisms like Schizosaccharomyces pombe has led to many important discoveries, the findings may not always translate directly to humans.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Electron microscopy (EM) is a type of microscopy that uses a beam of electrons to create an image of the sample being examined, resulting in much higher magnification and resolution than light microscopy. There are several types of electron microscopy, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), and reflection electron microscopy (REM).

In TEM, a beam of electrons is transmitted through a thin slice of the sample, and the electrons that pass through the sample are focused to form an image. This technique can provide detailed information about the internal structure of cells, viruses, and other biological specimens, as well as the composition and structure of materials at the atomic level.

In SEM, a beam of electrons is scanned across the surface of the sample, and the electrons that are scattered back from the surface are detected to create an image. This technique can provide information about the topography and composition of surfaces, as well as the structure of materials at the microscopic level.

REM is a variation of SEM in which the beam of electrons is reflected off the surface of the sample, rather than scattered back from it. This technique can provide information about the surface chemistry and composition of materials.

Electron microscopy has a wide range of applications in biology, medicine, and materials science, including the study of cellular structure and function, disease diagnosis, and the development of new materials and technologies.

Fertility agents for males are medications or supplements that are used to improve male fertility. They can work by increasing sperm count, improving sperm motility (movement), and enhancing overall sperm quality. Some examples of male fertility agents include:

1. Clomiphene citrate: This medication is typically used to treat infertility in women, but it can also be prescribed off-label for men with low sperm counts. It works by stimulating the production of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which are important for sperm production.
2. Gonadotropins: These are hormones that can be given as injections to stimulate the testicles to produce more testosterone and sperm. Human chorionic gonadotropin (hCG) and human menopausal gonadotropin (hMG) are examples of gonadotropins used for male fertility treatment.
3. Antioxidants: Certain antioxidant supplements, such as vitamin C, vitamin E, coenzyme Q10, and L-carnitine, have been shown to improve sperm quality by reducing oxidative stress and DNA damage in sperm cells.
4. Herbal supplements: Some herbs, such as tribulus terrestris, maca root, and ashwagandha, are believed to boost male fertility by increasing testosterone levels and improving sperm count and motility. However, their effectiveness is not well-established, and they should be used with caution under the guidance of a healthcare provider.
5. Varicocele repair: In some cases, a varicocele (dilated vein in the scrotum) can contribute to male infertility by increasing the temperature around the testicles and impairing sperm production. Surgical repair of a varicocele may be recommended to improve fertility.

It is important to consult with a healthcare provider before starting any fertility treatment, as these agents may have side effects or interact with other medications. A thorough evaluation of male fertility factors, such as hormone levels, semen analysis, and physical examination, should be performed to determine the most appropriate treatment approach.

Esterases are a group of enzymes that catalyze the hydrolysis of ester bonds in esters, producing alcohols and carboxylic acids. They are widely distributed in plants, animals, and microorganisms and play important roles in various biological processes, such as metabolism, digestion, and detoxification.

Esterases can be classified into several types based on their substrate specificity, including carboxylesterases, cholinesterases, lipases, and phosphatases. These enzymes have different structures and mechanisms of action but all share the ability to hydrolyze esters.

Carboxylesterases are the most abundant and diverse group of esterases, with a wide range of substrate specificity. They play important roles in the metabolism of drugs, xenobiotics, and lipids. Cholinesterases, on the other hand, specifically hydrolyze choline esters, such as acetylcholine, which is an important neurotransmitter in the nervous system. Lipases are a type of esterase that preferentially hydrolyzes triglycerides and plays a crucial role in fat digestion and metabolism. Phosphatases are enzymes that remove phosphate groups from various molecules, including esters, and have important functions in signal transduction and other cellular processes.

Esterases can also be used in industrial applications, such as in the production of biodiesel, detergents, and food additives. They are often produced by microbial fermentation or extracted from plants and animals. The use of esterases in biotechnology is an active area of research, with potential applications in biofuel production, bioremediation, and medical diagnostics.

DNA-binding proteins are a type of protein that have the ability to bind to DNA (deoxyribonucleic acid), the genetic material of organisms. These proteins play crucial roles in various biological processes, such as regulation of gene expression, DNA replication, repair and recombination.

The binding of DNA-binding proteins to specific DNA sequences is mediated by non-covalent interactions, including electrostatic, hydrogen bonding, and van der Waals forces. The specificity of binding is determined by the recognition of particular nucleotide sequences or structural features of the DNA molecule.

DNA-binding proteins can be classified into several categories based on their structure and function, such as transcription factors, histones, and restriction enzymes. Transcription factors are a major class of DNA-binding proteins that regulate gene expression by binding to specific DNA sequences in the promoter region of genes and recruiting other proteins to modulate transcription. Histones are DNA-binding proteins that package DNA into nucleosomes, the basic unit of chromatin structure. Restriction enzymes are DNA-binding proteins that recognize and cleave specific DNA sequences, and are widely used in molecular biology research and biotechnology applications.

Chromosomes in plants are thread-like structures that contain genetic material, DNA, and proteins. They are present in the nucleus of every cell and are inherited from the parent plants during sexual reproduction. Chromosomes come in pairs, with each pair consisting of one chromosome from each parent.

In plants, like in other organisms, chromosomes play a crucial role in inheritance, development, and reproduction. They carry genetic information that determines various traits and characteristics of the plant, such as its physical appearance, growth patterns, and resistance to diseases.

Plant chromosomes are typically much larger than those found in animals, making them easier to study under a microscope. The number of chromosomes varies among different plant species, ranging from as few as 2 in some ferns to over 1000 in certain varieties of wheat.

During cell division, the chromosomes replicate and then separate into two identical sets, ensuring that each new cell receives a complete set of genetic information. This process is critical for the growth and development of the plant, as well as for the production of viable seeds and offspring.

Medical Definition:
Microtubule-associated proteins (MAPs) are a diverse group of proteins that bind to microtubules, which are key components of the cytoskeleton in eukaryotic cells. MAPs play crucial roles in regulating microtubule dynamics and stability, as well as in mediating interactions between microtubules and other cellular structures. They can be classified into several categories based on their functions, including:

1. Microtubule stabilizers: These MAPs promote the assembly of microtubules and protect them from disassembly by enhancing their stability. Examples include tau proteins and MAP2.
2. Microtubule dynamics regulators: These MAPs modulate the rate of microtubule polymerization and depolymerization, allowing for dynamic reorganization of the cytoskeleton during cell division and other processes. Examples include stathmin and XMAP215.
3. Microtubule motor proteins: These MAPs use energy from ATP hydrolysis to move along microtubules, transporting various cargoes within the cell. Examples include kinesin and dynein.
4. Adapter proteins: These MAPs facilitate interactions between microtubules and other cellular structures, such as membranes, organelles, or signaling molecules. Examples include MAP4 and CLASPs.

Dysregulation of MAPs has been implicated in several diseases, including neurodegenerative disorders like Alzheimer's disease (where tau proteins form abnormal aggregates called neurofibrillary tangles) and cancer (where altered microtubule dynamics can contribute to uncontrolled cell division).

Saccharomycetales is an order of fungi that are commonly known as "true yeasts." They are characterized by their single-celled growth and ability to reproduce through budding or fission. These organisms are widely distributed in nature and can be found in a variety of environments, including soil, water, and on the surfaces of plants and animals.

Many species of Saccharomycetales are used in industrial processes, such as the production of bread, beer, and wine. They are also used in biotechnology to produce various enzymes, vaccines, and other products. Some species of Saccharomycetales can cause diseases in humans and animals, particularly in individuals with weakened immune systems. These infections, known as candidiasis or thrush, can affect various parts of the body, including the skin, mouth, and genital area.

The Nucleolus Organizer Region (NOR) is a specific region within the chromosomes, primarily in the short arm of the acrocentric chromosomes (chromosomes 13, 14, 15, 21, and 22). It consists of clusters of repetitive DNA sequences that encode ribosomal RNA (rRNA) genes. During interphase, these regions form the nucleolus, a distinct structure within the nucleus where rRNA transcription, processing, and ribosome assembly occur. The number of NORs in an individual can vary, which has implications in certain genetic conditions and aging processes.

Cytoplasm is the material within a eukaryotic cell (a cell with a true nucleus) that lies between the nuclear membrane and the cell membrane. It is composed of an aqueous solution called cytosol, in which various organelles such as mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles are suspended. Cytoplasm also contains a variety of dissolved nutrients, metabolites, ions, and enzymes that are involved in various cellular processes such as metabolism, signaling, and transport. It is where most of the cell's metabolic activities take place, and it plays a crucial role in maintaining the structure and function of the cell.

Phosphorylation is the process of adding a phosphate group (a molecule consisting of one phosphorus atom and four oxygen atoms) to a protein or other organic molecule, which is usually done by enzymes called kinases. This post-translational modification can change the function, localization, or activity of the target molecule, playing a crucial role in various cellular processes such as signal transduction, metabolism, and regulation of gene expression. Phosphorylation is reversible, and the removal of the phosphate group is facilitated by enzymes called phosphatases.

Chromosomes are thread-like structures that contain genetic material, i.e., DNA and proteins, present in the nucleus of human cells. In humans, there are 23 pairs of chromosomes, for a total of 46 chromosomes, in each diploid cell. Twenty-two of these pairs are called autosomal chromosomes, which come in identical pairs and contain genes that determine various traits unrelated to sex.

The last pair is referred to as the sex chromosomes (X and Y), which determines a person's biological sex. Females have two X chromosomes (46, XX), while males possess one X and one Y chromosome (46, XY). Chromosomes vary in size, with the largest being chromosome 1 and the smallest being the Y chromosome.

Human chromosomes are typically visualized during mitosis or meiosis using staining techniques that highlight their banding patterns, allowing for identification of specific regions and genes. Chromosomal abnormalities can lead to various genetic disorders, including Down syndrome (trisomy 21), Turner syndrome (monosomy X), and Klinefelter syndrome (XXY).

Kinesin is not a medical term per se, but a term from the field of cellular biology. However, understanding how kinesins work is important in the context of medical and cellular research.

Kinesins are a family of motor proteins that play a crucial role in transporting various cargoes within cells, such as vesicles, organelles, and chromosomes. They move along microtubule filaments, using the energy derived from ATP hydrolysis to generate mechanical force and motion. This process is essential for several cellular functions, including intracellular transport, mitosis, and meiosis.

In a medical context, understanding kinesin function can provide insights into various diseases and conditions related to impaired intracellular transport, such as neurodegenerative disorders (e.g., Alzheimer's disease, Parkinson's disease, and Huntington's disease) and certain genetic disorders affecting motor neurons. Research on kinesins can potentially lead to the development of novel therapeutic strategies targeting these conditions.

Chromosomes in insects are thread-like structures that contain genetic material, made up of DNA and proteins, found in the nucleus of a cell. In insects, like other eukaryotes, chromosomes come in pairs, with one set inherited from each parent. They are crucial for the inheritance, storage, and transmission of genetic information from one generation to the next.

Insects typically have a diploid number of chromosomes (2n), which varies among species. The chromosomes are present in the cell's nucleus during interphase as loosely coiled structures called chromatin. During cell division, they condense and become visible under the microscope as distinct, X-shaped structures called metaphase chromosomes.

The insect chromosome set includes autosomal chromosomes, which are identical in appearance and function between males and females, and sex chromosomes, which differ between males and females. In many insects, the males have an XY sex chromosome constitution, while the females have an XX sex chromosome constitution. The sex chromosomes carry genes that determine the sex of the individual.

Insect chromosomes play a vital role in various biological processes, including development, reproduction, and evolution. They are also essential for genetic research and breeding programs in agriculture and medicine.

An ovum is the female reproductive cell, or gamete, produced in the ovaries. It is also known as an egg cell and is released from the ovary during ovulation. When fertilized by a sperm, it becomes a zygote, which can develop into a fetus. The ovum contains half the genetic material necessary to create a new individual.

'Drosophila proteins' refer to the proteins that are expressed in the fruit fly, Drosophila melanogaster. This organism is a widely used model system in genetics, developmental biology, and molecular biology research. The study of Drosophila proteins has contributed significantly to our understanding of various biological processes, including gene regulation, cell signaling, development, and aging.

Some examples of well-studied Drosophila proteins include:

1. HSP70 (Heat Shock Protein 70): A chaperone protein involved in protein folding and protection from stress conditions.
2. TUBULIN: A structural protein that forms microtubules, important for cell division and intracellular transport.
3. ACTIN: A cytoskeletal protein involved in muscle contraction, cell motility, and maintenance of cell shape.
4. BETA-GALACTOSIDASE (LACZ): A reporter protein often used to monitor gene expression patterns in transgenic flies.
5. ENDOGLIN: A protein involved in the development of blood vessels during embryogenesis.
6. P53: A tumor suppressor protein that plays a crucial role in preventing cancer by regulating cell growth and division.
7. JUN-KINASE (JNK): A signaling protein involved in stress response, apoptosis, and developmental processes.
8. DECAPENTAPLEGIC (DPP): A member of the TGF-β (Transforming Growth Factor Beta) superfamily, playing essential roles in embryonic development and tissue homeostasis.

These proteins are often studied using various techniques such as biochemistry, genetics, molecular biology, and structural biology to understand their functions, interactions, and regulation within the cell.

Fungal proteins are a type of protein that is specifically produced and present in fungi, which are a group of eukaryotic organisms that include microorganisms such as yeasts and molds. These proteins play various roles in the growth, development, and survival of fungi. They can be involved in the structure and function of fungal cells, metabolism, pathogenesis, and other cellular processes. Some fungal proteins can also have important implications for human health, both in terms of their potential use as therapeutic targets and as allergens or toxins that can cause disease.

Fungal proteins can be classified into different categories based on their functions, such as enzymes, structural proteins, signaling proteins, and toxins. Enzymes are proteins that catalyze chemical reactions in fungal cells, while structural proteins provide support and protection for the cell. Signaling proteins are involved in communication between cells and regulation of various cellular processes, and toxins are proteins that can cause harm to other organisms, including humans.

Understanding the structure and function of fungal proteins is important for developing new treatments for fungal infections, as well as for understanding the basic biology of fungi. Research on fungal proteins has led to the development of several antifungal drugs that target specific fungal enzymes or other proteins, providing effective treatment options for a range of fungal diseases. Additionally, further study of fungal proteins may reveal new targets for drug development and help improve our ability to diagnose and treat fungal infections.

Cyclin A is a type of cyclin protein that regulates the progression of the cell cycle, particularly through the G1 and S phases. It forms a complex with and acts as a regulatory subunit for cyclin-dependent kinases (CDKs), specifically CDK2 and CDK1. The activation of Cyclin A-CDK complexes leads to phosphorylation of various target proteins, which in turn regulates DNA replication and the transition to mitosis.

Cyclin A levels rise during the late G1 phase and peak during the S phase, after which they decline rapidly during the G2 phase. Any abnormalities in Cyclin A regulation or expression can contribute to uncontrolled cell growth and cancer development.

"Saccharomyces cerevisiae" is not typically considered a medical term, but it is a scientific name used in the field of microbiology. It refers to a species of yeast that is commonly used in various industrial processes, such as baking and brewing. It's also widely used in scientific research due to its genetic tractability and eukaryotic cellular organization.

However, it does have some relevance to medical fields like medicine and nutrition. For example, certain strains of S. cerevisiae are used as probiotics, which can provide health benefits when consumed. They may help support gut health, enhance the immune system, and even assist in the digestion of certain nutrients.

In summary, "Saccharomyces cerevisiae" is a species of yeast with various industrial and potential medical applications.

Cell nucleus division, also known as nuclear division, is the process by which the genetic material within the cell nucleus, referred to as chromosomes, is separated into two equal sets in preparation for cell division. This process results in the formation of two daughter nuclei, each with a complete set of chromosomes.

There are two types of nuclear division: mitosis and meiosis.

Mitosis is the type of nuclear division that occurs in somatic cells (cells other than sex cells) during growth, repair, and maintenance of tissues. It results in the formation of two genetically identical daughter nuclei. The process of mitosis can be divided into several stages: prophase, prometaphase, metaphase, anaphase, and telophase.

Meiosis, on the other hand, is the type of nuclear division that occurs in sex cells (sperm and egg cells) during sexual reproduction. It results in the formation of four genetically unique daughter nuclei, each with half the number of chromosomes as the parent cell. Meiosis consists of two consecutive divisions: meiosis I and meiosis II.

Both types of nuclear division are essential for the growth, development, and reproduction of living organisms.

A Microtubule-Organizing Center (MTOC) is a cellular structure that organizes and nucleates microtubules, which are important components of the cytoskeleton. MTOCs are involved in various cellular processes such as cell division, intracellular transport, and maintenance of cell shape. The largest and most well-known MTOC is the centrosome, which is typically located near the nucleus of animal cells. However, there are other types of MTOCs, including the basal bodies of cilia and flagella, and the microtubule-organizing centers found in plant cells called plastids. Overall, MTOCs play a crucial role in maintaining the structural integrity and organization of the cell.

"Secale cereale" is the scientific name for a type of grass that is more commonly known as rye or ergot. It is often used as a food grain and also in the production of certain medicines. However, it's worth noting that ergot, which is a fungus that infects rye and other grains, can produce harmful compounds that can cause serious health problems if ingested. Therefore, it's important to handle and consume rye grain properly to avoid any potential risks.

Fertilization is the process by which a sperm cell (spermatozoon) penetrates and fuses with an egg cell (ovum), resulting in the formation of a zygote. This fusion of genetic material from both the male and female gametes initiates the development of a new organism. In human biology, fertilization typically occurs in the fallopian tube after sexual intercourse, when a single sperm out of millions is able to reach and penetrate the egg released from the ovary during ovulation. The successful fusion of these two gametes marks the beginning of pregnancy.

Video microscopy is a medical technique that involves the use of a microscope equipped with a video camera to capture and display real-time images of specimens on a monitor. This allows for the observation and documentation of dynamic processes, such as cell movement or chemical reactions, at a level of detail that would be difficult or impossible to achieve with the naked eye. Video microscopy can also be used in conjunction with image analysis software to measure various parameters, such as size, shape, and motion, of individual cells or structures within the specimen.

There are several types of video microscopy, including brightfield, darkfield, phase contrast, fluorescence, and differential interference contrast (DIC) microscopy. Each type uses different optical techniques to enhance contrast and reveal specific features of the specimen. For example, fluorescence microscopy uses fluorescent dyes or proteins to label specific structures within the specimen, allowing them to be visualized against a dark background.

Video microscopy is used in various fields of medicine, including pathology, microbiology, and neuroscience. It can help researchers and clinicians diagnose diseases, study disease mechanisms, develop new therapies, and understand fundamental biological processes at the cellular and molecular level.

Cell division is the process by which a single eukaryotic cell (a cell with a true nucleus) divides into two identical daughter cells. This complex process involves several stages, including replication of DNA, separation of chromosomes, and division of the cytoplasm. There are two main types of cell division: mitosis and meiosis.

Mitosis is the type of cell division that results in two genetically identical daughter cells. It is a fundamental process for growth, development, and tissue repair in multicellular organisms. The stages of mitosis include prophase, prometaphase, metaphase, anaphase, and telophase, followed by cytokinesis, which divides the cytoplasm.

Meiosis, on the other hand, is a type of cell division that occurs in the gonads (ovaries and testes) during the production of gametes (sex cells). Meiosis results in four genetically unique daughter cells, each with half the number of chromosomes as the parent cell. This process is essential for sexual reproduction and genetic diversity. The stages of meiosis include meiosis I and meiosis II, which are further divided into prophase, prometaphase, metaphase, anaphase, and telophase.

In summary, cell division is the process by which a single cell divides into two daughter cells, either through mitosis or meiosis. This process is critical for growth, development, tissue repair, and sexual reproduction in multicellular organisms.

Centrioles are small, cylindrical structures found in the centrosome of animal cells. They play a crucial role in organizing the microtubules that make up the cell's cytoskeleton and are also involved in the formation of the spindle apparatus during cell division. A typical centriole is made up of nine sets of triplet microtubules arranged in a ring-like fashion around a central hub or core.

Centrioles have two main functions:

1. Microtubule Organization: Centrioles serve as the primary site for microtubule nucleation and organization within the cell. They help to form the mitotic spindle during cell division, which is responsible for separating replicated chromosomes into two identical sets that are distributed equally between the two daughter cells.

2. Formation of Cilia and Flagella: In specialized cells, centrioles can also function as basal bodies for the formation of cilia and flagella. These hair-like structures protrude from the cell surface and play a role in cell movement and the movement of extracellular fluids over the cell surface.

It is important to note that plants and fungi do not have centrioles, and their cells use alternative mechanisms for microtubule organization and cell division.

Green Fluorescent Protein (GFP) is not a medical term per se, but a scientific term used in the field of molecular biology. GFP is a protein that exhibits bright green fluorescence when exposed to light, particularly blue or ultraviolet light. It was originally discovered in the jellyfish Aequorea victoria.

In medical and biological research, scientists often use recombinant DNA technology to introduce the gene for GFP into other organisms, including bacteria, plants, and animals, including humans. This allows them to track the expression and localization of specific genes or proteins of interest in living cells, tissues, or even whole organisms.

The ability to visualize specific cellular structures or processes in real-time has proven invaluable for a wide range of research areas, from studying the development and function of organs and organ systems to understanding the mechanisms of diseases and the effects of therapeutic interventions.

Diploidy is a term used in genetics to describe the state of having two sets of chromosomes in each cell. In diploid organisms, one set of chromosomes is inherited from each parent, resulting in a total of 2 sets of chromosomes.

In humans, for example, most cells are diploid and contain 46 chromosomes arranged in 23 pairs. This includes 22 pairs of autosomal chromosomes and one pair of sex chromosomes (XX in females or XY in males). Diploidy is a characteristic feature of many complex organisms, including animals, plants, and fungi.

Diploid cells can undergo a process called meiosis, which results in the formation of haploid cells that contain only one set of chromosomes. These haploid cells can then combine with other haploid cells during fertilization to form a new diploid organism.

Abnormalities in diploidy can lead to genetic disorders, such as Down syndrome, which occurs when an individual has three copies of chromosome 21 instead of the typical two. This extra copy of the chromosome can result in developmental delays and intellectual disabilities.

"Xenopus proteins" refer to the proteins that are expressed or isolated from the Xenopus species, which are primarily used as model organisms in biological and biomedical research. The most commonly used Xenopus species for research are the African clawed frogs, Xenopus laevis and Xenopus tropicalis. These proteins play crucial roles in various cellular processes and functions, and they serve as valuable tools to study different aspects of molecular biology, developmental biology, genetics, and biochemistry.

Some examples of Xenopus proteins that are widely studied include:

1. Xenopus Histones: These are the proteins that package DNA into nucleosomes, which are the fundamental units of chromatin in eukaryotic cells. They play a significant role in gene regulation and epigenetic modifications.
2. Xenopus Cyclins and Cyclin-dependent kinases (CDKs): These proteins regulate the cell cycle and control cell division, differentiation, and apoptosis.
3. Xenopus Transcription factors: These proteins bind to specific DNA sequences and regulate gene expression during development and in response to various stimuli.
4. Xenopus Signaling molecules: These proteins are involved in intracellular signaling pathways that control various cellular processes, such as cell growth, differentiation, migration, and survival.
5. Xenopus Cytoskeletal proteins: These proteins provide structural support to the cells and regulate their shape, motility, and organization.
6. Xenopus Enzymes: These proteins catalyze various biochemical reactions in the cell, such as metabolic pathways, DNA replication, transcription, and translation.

Overall, Xenopus proteins are essential tools for understanding fundamental biological processes and have contributed significantly to our current knowledge of molecular biology, genetics, and developmental biology.

Sister chromatid exchange (SCE) is a type of genetic recombination that takes place between two identical sister chromatids during the DNA repair process in meiosis or mitosis. It results in an exchange of genetic material between the two chromatids, creating a new combination of genes on each chromatid. This event is a normal part of cell division and helps to increase genetic variability within a population. However, an increased rate of SCEs can also be indicative of exposure to certain genotoxic agents or conditions that cause DNA damage.

Heterochromatin is a type of chromatin (the complex of DNA, RNA, and proteins that make up chromosomes) that is characterized by its tightly packed structure and reduced genetic activity. It is often densely stained with certain dyes due to its high concentration of histone proteins and other chromatin-associated proteins. Heterochromatin can be further divided into two subtypes: constitutive heterochromatin, which is consistently highly condensed and transcriptionally inactive throughout the cell cycle, and facultative heterochromatin, which can switch between a condensed, inactive state and a more relaxed, active state depending on the needs of the cell. Heterochromatin plays important roles in maintaining the stability and integrity of the genome by preventing the transcription of repetitive DNA sequences and protecting against the spread of transposable elements.

Microinjection is a medical technique that involves the use of a fine, precise needle to inject small amounts of liquid or chemicals into microscopic structures, cells, or tissues. This procedure is often used in research settings to introduce specific substances into individual cells for study purposes, such as introducing DNA or RNA into cell nuclei to manipulate gene expression.

In clinical settings, microinjections may be used in various medical and cosmetic procedures, including:

1. Intracytoplasmic Sperm Injection (ICSI): A type of assisted reproductive technology where a single sperm is injected directly into an egg to increase the chances of fertilization during in vitro fertilization (IVF) treatments.
2. Botulinum Toxin Injections: Microinjections of botulinum toxin (Botox, Dysport, or Xeomin) are used for cosmetic purposes to reduce wrinkles and fine lines by temporarily paralyzing the muscles responsible for their formation. They can also be used medically to treat various neuromuscular disorders, such as migraines, muscle spasticity, and excessive sweating (hyperhidrosis).
3. Drug Delivery: Microinjections may be used to deliver drugs directly into specific tissues or organs, bypassing the systemic circulation and potentially reducing side effects. This technique can be particularly useful in treating localized pain, delivering growth factors for tissue regeneration, or administering chemotherapy agents directly into tumors.
4. Gene Therapy: Microinjections of genetic material (DNA or RNA) can be used to introduce therapeutic genes into cells to treat various genetic disorders or diseases, such as cystic fibrosis, hemophilia, or cancer.

Overall, microinjection is a highly specialized and precise technique that allows for the targeted delivery of substances into small structures, cells, or tissues, with potential applications in research, medical diagnostics, and therapeutic interventions.

Male infertility is a condition characterized by the inability to cause pregnancy in a fertile female. It is typically defined as the failure to achieve a pregnancy after 12 months or more of regular unprotected sexual intercourse.

The causes of male infertility can be varied and include issues with sperm production, such as low sperm count or poor sperm quality, problems with sperm delivery, such as obstructions in the reproductive tract, or hormonal imbalances that affect sperm production. Other factors that may contribute to male infertility include genetic disorders, environmental exposures, lifestyle choices, and certain medical conditions or treatments.

It is important to note that male infertility can often be treated or managed with medical interventions, such as medication, surgery, or assisted reproductive technologies (ART). A healthcare provider can help diagnose the underlying cause of male infertility and recommend appropriate treatment options.

Proto-oncogene proteins c-mos are a type of serine/threonine protein kinase that play crucial roles in cell cycle regulation, particularly during the G2 phase and the transition to mitosis. The c-mos gene is a normal version of an oncogene, which can become cancer-causing when mutated or overexpressed. In its normal form, the c-mos protein is involved in controlling the progression of the cell cycle, meiosis, and also has been implicated in neuronal development and synaptic plasticity. Dysregulation of c-mos proto-oncogene proteins can contribute to tumorigenesis and cancer development.

'Zea mays' is the biological name for corn or maize, which is not typically considered a medical term. However, corn or maize can have medical relevance in certain contexts. For example, cornstarch is sometimes used as a diluent for medications and is also a component of some skin products. Corn oil may be found in topical ointments and creams. In addition, some people may have allergic reactions to corn or corn-derived products. But generally speaking, 'Zea mays' itself does not have a specific medical definition.

"Drosophila" is a genus of small flies, also known as fruit flies. The most common species used in scientific research is "Drosophila melanogaster," which has been a valuable model organism for many areas of biological and medical research, including genetics, developmental biology, neurobiology, and aging.

The use of Drosophila as a model organism has led to numerous important discoveries in genetics and molecular biology, such as the identification of genes that are associated with human diseases like cancer, Parkinson's disease, and obesity. The short reproductive cycle, large number of offspring, and ease of genetic manipulation make Drosophila a powerful tool for studying complex biological processes.

Cell cycle checkpoints are control mechanisms that regulate the cell cycle and ensure the accurate and timely progression through different phases of the cell cycle. These checkpoints monitor specific cellular events, such as DNA replication and damage, chromosome separation, and proper attachment of the mitotic spindle to the chromosomes. If any of these events fail to occur properly or are delayed, the cell cycle checkpoints trigger a response that can halt the cell cycle until the problem is resolved. This helps to prevent cells with damaged or incomplete genomes from dividing and potentially becoming cancerous.

There are three main types of cell cycle checkpoints:

1. G1 Checkpoint: Also known as the restriction point, this checkpoint controls the transition from the G1 phase to the S phase of the cell cycle. It monitors the availability of nutrients, growth factors, and the integrity of the genome before allowing the cell to proceed into DNA replication.
2. G2 Checkpoint: This checkpoint regulates the transition from the G2 phase to the M phase of the cell cycle. It checks for completion of DNA replication and absence of DNA damage before allowing the cell to enter mitosis.
3. Mitotic (M) Checkpoint: Also known as the spindle assembly checkpoint, this checkpoint ensures that all chromosomes are properly attached to the mitotic spindle before anaphase begins. It prevents the separation of sister chromatids until all kinetochores are correctly attached and tension is established between them.

Cell cycle checkpoints play a crucial role in maintaining genomic stability, preventing tumorigenesis, and ensuring proper cell division. Dysregulation of these checkpoints can lead to various diseases, including cancer.

Nuclear antigens are proteins or other molecules found in the nucleus of a cell that can stimulate an immune response and produce antibodies when they are recognized as foreign by the body's immune system. These antigens are normally located inside the cell and are not typically exposed to the immune system, but under certain circumstances, such as during cell death or damage, they may be released and become targets of the immune system.

Nuclear antigens can play a role in the development of some autoimmune diseases, such as systemic lupus erythematosus (SLE), where the body's immune system mistakenly attacks its own cells and tissues. In SLE, nuclear antigens such as double-stranded DNA and nucleoproteins are common targets of the abnormal immune response.

Testing for nuclear antigens is often used in the diagnosis and monitoring of autoimmune diseases. For example, a positive test for anti-double-stranded DNA antibodies is a specific indicator of SLE and can help confirm the diagnosis. However, it's important to note that not all people with SLE will have positive nuclear antigen tests, and other factors must also be considered in making a diagnosis.

Sordariales is an order of fungi in the class Sordariomycetes, which are characterized by their perithecial ascomata (sexual fruiting bodies) with cylindrical to allantoid (sausage-shaped) asci (ascus = sac-like structure containing ascospores). The order includes both saprobic and pathogenic species. Some notable members of Sordariales are:

1. Neurospora crassa - A model organism used in genetics, molecular biology, and biochemistry research. It is a filamentous ascomycete fungus with a worldwide distribution and is commonly found on decaying plant material.
2. Sordaria fimicola - Another model organism for genetic studies, particularly in the field of meiosis and genetics of sexual reproduction.
3. Chaetomium globosum - A saprobic fungus that can be isolated from various substrates such as soil, dung, and decaying plant material. It is also known to cause opportunistic infections in humans.
4. Xylaria hypoxylon - A wood-decay fungus commonly found on dead or dying trees and branches. Some species are capable of causing rot in living plants.
5. Graphostroma platystomum - A pathogenic fungus that causes canker diseases in various tree species, such as oak, beech, and chestnut.

The order Sordariales is primarily defined by its unique ascus morphology and the presence of certain molecular markers, such as specific genes related to the sexual reproduction process.

Sertoli cells, also known as sustentacular cells or nurse cells, are specialized cells in the seminiferous tubules of the testis in mammals. They play a crucial role in supporting and nurturing the development of sperm cells (spermatogenesis). Sertoli cells create a microenvironment within the seminiferous tubules that facilitates the differentiation, maturation, and survival of germ cells.

These cells have several essential functions:

1. Blood-testis barrier formation: Sertoli cells form tight junctions with each other, creating a physical barrier called the blood-testis barrier, which separates the seminiferous tubules into basal and adluminal compartments. This barrier protects the developing sperm cells from the immune system and provides an isolated environment for their maturation.
2. Nutrition and support: Sertoli cells provide essential nutrients and growth factors to germ cells, ensuring their proper development and survival. They also engulf and digest residual bodies, which are byproducts of spermatid differentiation.
3. Phagocytosis: Sertoli cells have phagocytic properties, allowing them to remove debris and dead cells within the seminiferous tubules.
4. Hormone metabolism: Sertoli cells express receptors for various hormones, such as follicle-stimulating hormone (FSH), testosterone, and estradiol. They play a role in regulating hormonal signaling within the testis by metabolizing these hormones or producing inhibins, which modulate FSH secretion from the pituitary gland.
5. Regulation of spermatogenesis: Sertoli cells produce and secrete various proteins and growth factors that influence germ cell development and proliferation. They also control the release of mature sperm cells into the epididymis through a process called spermiation.

A nonmammalian embryo refers to the developing organism in animals other than mammals, from the fertilized egg (zygote) stage until hatching or birth. In nonmammalian species, the developmental stages and terminology differ from those used in mammals. The term "embryo" is generally applied to the developing organism up until a specific stage of development that is characterized by the formation of major organs and structures. After this point, the developing organism is referred to as a "larva," "juvenile," or other species-specific terminology.

The study of nonmammalian embryos has played an important role in our understanding of developmental biology and evolutionary developmental biology (evo-devo). By comparing the developmental processes across different animal groups, researchers can gain insights into the evolutionary origins and diversification of body plans and structures. Additionally, nonmammalian embryos are often used as model systems for studying basic biological processes, such as cell division, gene regulation, and pattern formation.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Luminescent proteins are a type of protein that emit light through a chemical reaction, rather than by absorbing and re-emitting light like fluorescent proteins. This process is called bioluminescence. The light emitted by luminescent proteins is often used in scientific research as a way to visualize and track biological processes within cells and organisms.

One of the most well-known luminescent proteins is Green Fluorescent Protein (GFP), which was originally isolated from jellyfish. However, GFP is actually a fluorescent protein, not a luminescent one. A true example of a luminescent protein is the enzyme luciferase, which is found in fireflies and other bioluminescent organisms. When luciferase reacts with its substrate, luciferin, it produces light through a process called oxidation.

Luminescent proteins have many applications in research, including as reporters for gene expression, as markers for protein-protein interactions, and as tools for studying the dynamics of cellular processes. They are also used in medical imaging and diagnostics, as well as in the development of new therapies.

CDC28 protein kinase in Saccharomyces cerevisiae (Baker's yeast) is a crucial cell cycle regulator, specifically a cyclin-dependent kinase (CDK). It plays a pivotal role in controlling the G1 to S phase transition during the cell division cycle. CDC28 forms complexes with various cyclins, such as G1 cyclins CLN1, CLN2, and CLN3, and S phase cyclin CLB5, to regulate different stages of the cell cycle. The activity of CDC28 is tightly controlled through phosphorylation, dephosphorylation, and proteolysis of the cyclin subunits. Inhibition or mutation of CDC28 can lead to cell cycle arrest and various developmental defects in yeast.

Nuclear Receptor Subfamily 6, Group A, Member 1 (NR6A1) is a gene that encodes for the steroidogenic factor-1 (SF-1) protein, which is a member of the nuclear receptor superfamily. These proteins are transcription factors that regulate gene expression by binding to specific DNA sequences.

The SF-1 protein plays critical roles in the development and function of the endocrine system, including the regulation of steroid hormone biosynthesis, gonadal development, and reproductive function. Mutations in the NR6A1 gene have been associated with several genetic disorders, such as congenital adrenal hyperplasia, primary ovarian insufficiency, and XY female disorder of sex development.

Protein kinases are a group of enzymes that play a crucial role in many cellular processes by adding phosphate groups to other proteins, a process known as phosphorylation. This modification can activate or deactivate the target protein's function, thereby regulating various signaling pathways within the cell. Protein kinases are essential for numerous biological functions, including metabolism, signal transduction, cell cycle progression, and apoptosis (programmed cell death). Abnormal regulation of protein kinases has been implicated in several diseases, such as cancer, diabetes, and neurological disorders.

Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.

Examples of biological models include:

1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.

Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.

The nuclear matrix is a complex network of fibrous proteins that forms the structural framework inside the nucleus of a cell. It is involved in various essential cellular processes, such as DNA replication, transcription, repair, and RNA processing. The nuclear matrix provides a platform for these activities by organizing and compacting chromatin, maintaining the spatial organization of the nucleus, and interacting with regulatory proteins and nuclear enzymes. It's crucial for preserving genome stability and regulating gene expression.

"Xenopus" is not a medical term, but it is a genus of highly invasive aquatic frogs native to sub-Saharan Africa. They are often used in scientific research, particularly in developmental biology and genetics. The most commonly studied species is Xenopus laevis, also known as the African clawed frog.

In a medical context, Xenopus might be mentioned when discussing their use in research or as a model organism to study various biological processes or diseases.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

DNA repair is the process by which cells identify and correct damage to the DNA molecules that encode their genome. DNA can be damaged by a variety of internal and external factors, such as radiation, chemicals, and metabolic byproducts. If left unrepaired, this damage can lead to mutations, which may in turn lead to cancer and other diseases.

There are several different mechanisms for repairing DNA damage, including:

1. Base excision repair (BER): This process repairs damage to a single base in the DNA molecule. An enzyme called a glycosylase removes the damaged base, leaving a gap that is then filled in by other enzymes.
2. Nucleotide excision repair (NER): This process repairs more severe damage, such as bulky adducts or crosslinks between the two strands of the DNA molecule. An enzyme cuts out a section of the damaged DNA, and the gap is then filled in by other enzymes.
3. Mismatch repair (MMR): This process repairs errors that occur during DNA replication, such as mismatched bases or small insertions or deletions. Specialized enzymes recognize the error and remove a section of the newly synthesized strand, which is then replaced by new nucleotides.
4. Double-strand break repair (DSBR): This process repairs breaks in both strands of the DNA molecule. There are two main pathways for DSBR: non-homologous end joining (NHEJ) and homologous recombination (HR). NHEJ directly rejoins the broken ends, while HR uses a template from a sister chromatid to repair the break.

Overall, DNA repair is a crucial process that helps maintain genome stability and prevent the development of diseases caused by genetic mutations.

Phosphoproteins are proteins that have been post-translationally modified by the addition of a phosphate group (-PO3H2) onto specific amino acid residues, most commonly serine, threonine, or tyrosine. This process is known as phosphorylation and is mediated by enzymes called kinases. Phosphoproteins play crucial roles in various cellular processes such as signal transduction, cell cycle regulation, metabolism, and gene expression. The addition or removal of a phosphate group can activate or inhibit the function of a protein, thereby serving as a switch to control its activity. Phosphoproteins can be detected and quantified using techniques such as Western blotting, mass spectrometry, and immunofluorescence.

Deoxyribonucleic acid (DNA) is the genetic material present in the cells of organisms where it is responsible for the storage and transmission of hereditary information. DNA is a long molecule that consists of two strands coiled together to form a double helix. Each strand is made up of a series of four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - that are linked together by phosphate and sugar groups. The sequence of these bases along the length of the molecule encodes genetic information, with A always pairing with T and C always pairing with G. This base-pairing allows for the replication and transcription of DNA, which are essential processes in the functioning and reproduction of all living organisms.

Cytokinesis is the part of the cell division process (mitosis or meiosis) in which the cytoplasm of a single eukaryotic cell divides into two daughter cells. It usually begins after telophase, and it involves the constriction of a contractile ring composed of actin filaments and myosin motor proteins that forms at the equatorial plane of the cell. This results in the formation of a cleavage furrow, which deepens and eventually leads to the physical separation of the two daughter cells. Cytokinesis is essential for cell reproduction and growth in multicellular organisms, and its failure can lead to various developmental abnormalities or diseases.

Genes are the fundamental units of heredity in living organisms. They are made up of DNA (deoxyribonucleic acid) and are located on chromosomes. Genes carry the instructions for the development and function of an organism, including its physical and behavioral traits.

Helminths, also known as parasitic worms, are a type of parasite that can infect various organs and tissues in humans and animals. They have complex life cycles that involve multiple hosts and stages of development. Examples of helminths include roundworms, tapeworms, and flukes.

In the context of genetics, genes from helminths are studied to understand their role in the biology and evolution of these parasites, as well as to identify potential targets for the development of new drugs or vaccines to control or eliminate helminth infections. This involves studying the genetic makeup of helminths, including their DNA, RNA, and proteins, and how they interact with their hosts and the environment.

Macropodidae is not a medical term, but a taxonomic family in the order Diprotodontia, which includes large marsupials commonly known as kangaroos, wallabies, and tree-kangaroos. These animals are native to Australia and New Guinea. They are characterized by their strong hind legs, large feet adapted for leaping, and a long muscular tail used for balance. Some members of this family, particularly the larger kangaroo species, can pose a risk to humans in certain situations, such as vehicle collisions or aggressive encounters during breeding season. However, they are not typically associated with medical conditions or human health.

In the context of medicine, spores are typically discussed in relation to certain types of infections and diseases caused by microorganisms such as bacteria or fungi. Spores are a dormant, resistant form of these microorganisms that can survive under harsh environmental conditions, such as extreme temperatures, lack of nutrients, and exposure to chemicals.

Spores can be highly resistant to heat, radiation, and disinfectants, making them difficult to eliminate from contaminated surfaces or medical equipment. When the conditions are favorable, spores can germinate and grow into mature microorganisms that can cause infection.

Some examples of medically relevant spores include those produced by Clostridioides difficile (C. diff), a bacterium that can cause severe diarrhea and colitis in hospitalized patients, and Aspergillus fumigatus, a fungus that can cause invasive pulmonary aspergillosis in immunocompromised individuals.

It's worth noting that spores are not unique to medical contexts and have broader relevance in fields such as botany, mycology, and biology.

The G2 phase cell cycle checkpoint is a point in the cell cycle, specifically in the G2 phase, where the cell checks for any DNA damage or other issues that may have occurred during the DNA synthesis phase (S phase) before proceeding to mitosis. This checkpoint serves as a quality control mechanism to ensure that the genetic material is accurately and completely replicated and that the cell is ready to divide. If DNA damage or other problems are detected, the cell cycle is halted at the G2 checkpoint until the issues can be resolved. If the damage is too severe or cannot be repaired, the cell may undergo programmed cell death (apoptosis) to prevent the propagation of potentially harmful mutations.

Mammalian chromosomes are thread-like structures that exist in the nucleus of mammalian cells, consisting of DNA, hist proteins, and RNA. They carry genetic information that is essential for the development and function of all living organisms. In mammals, each cell contains 23 pairs of chromosomes, for a total of 46 chromosomes, with one set inherited from the mother and the other from the father.

The chromosomes are typically visualized during cell division, where they condense and become visible under a microscope. Each chromosome is composed of two identical arms, separated by a constriction called the centromere. The short arm of the chromosome is labeled as "p," while the long arm is labeled as "q."

Mammalian chromosomes play a critical role in the transmission of genetic information from one generation to the next and are essential for maintaining the stability and integrity of the genome. Abnormalities in the number or structure of mammalian chromosomes can lead to various genetic disorders, including Down syndrome, Turner syndrome, and Klinefelter syndrome.

Developmental gene expression regulation refers to the processes that control the activation or repression of specific genes during embryonic and fetal development. These regulatory mechanisms ensure that genes are expressed at the right time, in the right cells, and at appropriate levels to guide proper growth, differentiation, and morphogenesis of an organism.

Developmental gene expression regulation is a complex and dynamic process involving various molecular players, such as transcription factors, chromatin modifiers, non-coding RNAs, and signaling molecules. These regulators can interact with cis-regulatory elements, like enhancers and promoters, to fine-tune the spatiotemporal patterns of gene expression during development.

Dysregulation of developmental gene expression can lead to various congenital disorders and developmental abnormalities. Therefore, understanding the principles and mechanisms governing developmental gene expression regulation is crucial for uncovering the etiology of developmental diseases and devising potential therapeutic strategies.

Demecolcine is a medication that belongs to the class of drugs called anticholinergics. It is derived from the plant alkaloid colchicine and has been used in medical research for its ability to arrest cells in metaphase, a specific stage of cell division. This property makes demecolcine useful in various laboratory procedures such as chromosome analysis and the production of cultured cell lines.

In clinical settings, demecolcine is not commonly used due to its narrow therapeutic index and potential for toxicity. However, it has been used off-label in some cases to treat conditions associated with uncontrolled cell division, such as certain types of cancer. Its use in these situations is typically reserved for when other treatments have failed or are not well tolerated.

It's important to note that demecolcine should only be administered under the close supervision of a healthcare professional and its use is generally avoided in pregnant women due to the risk of fetal harm.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

Heteroptera is not a medical term, but a taxonomic category in zoology. It refers to a suborder of insects within the order Hemiptera, also known as true bugs. This group includes a wide variety of species, such as bed bugs, assassin bugs, and stink bugs. While Heteroptera is not directly related to human health or medicine, some species can have medical importance as disease vectors or pests.

Infertility is a reproductive health disorder defined as the failure to achieve a clinical pregnancy after 12 months or more of regular, unprotected sexual intercourse or due to an impairment of a person's capacity to reproduce either as an individual or with their partner. It can be caused by various factors in both men and women, including hormonal imbalances, structural abnormalities, genetic issues, infections, age, lifestyle factors, and others. Infertility can have significant emotional and psychological impacts on individuals and couples experiencing it, and medical intervention may be necessary to help them conceive.

A plant cell is defined as a type of eukaryotic cell that makes up the structural basis of plants and other forms of multicellular plant-like organisms, such as algae and mosses. These cells are typically characterized by their rigid cell walls, which provide support and protection, and their large vacuoles, which store nutrients and help maintain turgor pressure within the cell.

Plant cells also contain chloroplasts, organelles that carry out photosynthesis and give plants their green color. Other distinctive features of plant cells include a large central vacuole, a complex system of membranes called the endoplasmic reticulum, and numerous mitochondria, which provide energy to the cell through cellular respiration.

Plant cells are genetically distinct from animal cells, and they have unique structures and functions that allow them to carry out photosynthesis, grow and divide, and respond to their environment. Understanding the structure and function of plant cells is essential for understanding how plants grow, develop, and interact with their surroundings.

'Drosophila melanogaster' is the scientific name for a species of fruit fly that is commonly used as a model organism in various fields of biological research, including genetics, developmental biology, and evolutionary biology. Its small size, short generation time, large number of offspring, and ease of cultivation make it an ideal subject for laboratory studies. The fruit fly's genome has been fully sequenced, and many of its genes have counterparts in the human genome, which facilitates the understanding of genetic mechanisms and their role in human health and disease.

Here is a brief medical definition:

Drosophila melanogaster (droh-suh-fih-luh meh-lon-guh-ster): A species of fruit fly used extensively as a model organism in genetic, developmental, and evolutionary research. Its genome has been sequenced, revealing many genes with human counterparts, making it valuable for understanding genetic mechanisms and their role in human health and disease.

Securin is not a medical term, but rather a biological concept related to cell division. It's a protein that plays a crucial role in the regulation of chromosome separation during cell division (mitosis).

During mitosis, sister chromatids (identical copies of a chromosome) are held together by cohesin proteins until it's time for them to separate and move to opposite ends of the cell. Securin is one of the proteins that helps regulate this process. Specifically, securin inhibits an enzyme called separase, which is responsible for cleaving the cohesin rings that hold sister chromatids together.

Once the cell is ready to separate its chromosomes, a protease called separase is activated and degrades securin. This allows separase to cleave the cohesin rings, leading to the separation of sister chromatids and the continuation of mitosis. If securin function is disrupted, it can lead to errors in chromosome segregation, which can contribute to genomic instability and diseases like cancer.

CDC20 proteins are a type of regulatory protein that play a crucial role in the cell cycle, which is the process by which cells grow and divide. Specifically, CDC20 proteins are involved in the transition from metaphase to anaphase during mitosis, the phase of the cell cycle where chromosomes are separated and distributed to two daughter cells.

CDC20 proteins function as part of a larger complex called the anaphase-promoting complex/cyclosome (APC/C), which targets specific proteins for degradation by the proteasome. During metaphase, CDC20 binds to the APC/C and helps to activate it, leading to the degradation of securin and cyclin B, two proteins that are essential for maintaining the proper attachment of chromosomes to the spindle apparatus.

Once these proteins are degraded, the sister chromatids can be separated and moved to opposite poles of the cell, allowing for the completion of mitosis and the formation of two genetically identical daughter cells. In addition to their role in mitosis, CDC20 proteins have also been implicated in other cellular processes, including meiosis, DNA damage repair, and apoptosis.

Recombinant fusion proteins are artificially created biomolecules that combine the functional domains or properties of two or more different proteins into a single protein entity. They are generated through recombinant DNA technology, where the genes encoding the desired protein domains are linked together and expressed as a single, chimeric gene in a host organism, such as bacteria, yeast, or mammalian cells.

The resulting fusion protein retains the functional properties of its individual constituent proteins, allowing for novel applications in research, diagnostics, and therapeutics. For instance, recombinant fusion proteins can be designed to enhance protein stability, solubility, or immunogenicity, making them valuable tools for studying protein-protein interactions, developing targeted therapies, or generating vaccines against infectious diseases or cancer.

Examples of recombinant fusion proteins include:

1. Etaglunatide (ABT-523): A soluble Fc fusion protein that combines the heavy chain fragment crystallizable region (Fc) of an immunoglobulin with the extracellular domain of the human interleukin-6 receptor (IL-6R). This fusion protein functions as a decoy receptor, neutralizing IL-6 and its downstream signaling pathways in rheumatoid arthritis.
2. Etanercept (Enbrel): A soluble TNF receptor p75 Fc fusion protein that binds to tumor necrosis factor-alpha (TNF-α) and inhibits its proinflammatory activity, making it a valuable therapeutic option for treating autoimmune diseases like rheumatoid arthritis, ankylosing spondylitis, and psoriasis.
3. Abatacept (Orencia): A fusion protein consisting of the extracellular domain of cytotoxic T-lymphocyte antigen 4 (CTLA-4) linked to the Fc region of an immunoglobulin, which downregulates T-cell activation and proliferation in autoimmune diseases like rheumatoid arthritis.
4. Belimumab (Benlysta): A monoclonal antibody that targets B-lymphocyte stimulator (BLyS) protein, preventing its interaction with the B-cell surface receptor and inhibiting B-cell activation in systemic lupus erythematosus (SLE).
5. Romiplostim (Nplate): A fusion protein consisting of a thrombopoietin receptor agonist peptide linked to an immunoglobulin Fc region, which stimulates platelet production in patients with chronic immune thrombocytopenia (ITP).
6. Darbepoetin alfa (Aranesp): A hyperglycosylated erythropoiesis-stimulating protein that functions as a longer-acting form of recombinant human erythropoietin, used to treat anemia in patients with chronic kidney disease or cancer.
7. Palivizumab (Synagis): A monoclonal antibody directed against the F protein of respiratory syncytial virus (RSV), which prevents RSV infection and is administered prophylactically to high-risk infants during the RSV season.
8. Ranibizumab (Lucentis): A recombinant humanized monoclonal antibody fragment that binds and inhibits vascular endothelial growth factor A (VEGF-A), used in the treatment of age-related macular degeneration, diabetic retinopathy, and other ocular disorders.
9. Cetuximab (Erbitux): A chimeric monoclonal antibody that binds to epidermal growth factor receptor (EGFR), used in the treatment of colorectal cancer and head and neck squamous cell carcinoma.
10. Adalimumab (Humira): A fully humanized monoclonal antibody that targets tumor necrosis factor-alpha (TNF-α), used in the treatment of various inflammatory diseases, including rheumatoid arthritis, psoriasis, and Crohn's disease.
11. Bevacizumab (Avastin): A recombinant humanized monoclonal antibody that binds to VEGF-A, used in the treatment of various cancers, including colorectal, lung, breast, and kidney cancer.
12. Trastuzumab (Herceptin): A humanized monoclonal antibody that targets HER2/neu receptor, used in the treatment of breast cancer.
13. Rituximab (Rituxan): A chimeric monoclonal antibody that binds to CD20 antigen on B cells, used in the treatment of non-Hodgkin's lymphoma and rheumatoid arthritis.
14. Palivizumab (Synagis): A humanized monoclonal antibody that binds to the F protein of respiratory syncytial virus, used in the prevention of respiratory syncytial virus infection in high-risk infants.
15. Infliximab (Remicade): A chimeric monoclonal antibody that targets TNF-α, used in the treatment of various inflammatory diseases, including Crohn's disease, ulcerative colitis, rheumatoid arthritis, and ankylosing spondylitis.
16. Natalizumab (Tysabri): A humanized monoclonal antibody that binds to α4β1 integrin, used in the treatment of multiple sclerosis and Crohn's disease.
17. Adalimumab (Humira): A fully human monoclonal antibody that targets TNF-α, used in the treatment of various inflammatory diseases, including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, and ulcerative colitis.
18. Golimumab (Simponi): A fully human monoclonal antibody that targets TNF-α, used in the treatment of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and ulcerative colitis.
19. Certolizumab pegol (Cimzia): A PEGylated Fab' fragment of a humanized monoclonal antibody that targets TNF-α, used in the treatment of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and Crohn's disease.
20. Ustekinumab (Stelara): A fully human monoclonal antibody that targets IL-12 and IL-23, used in the treatment of psoriasis, psoriatic arthritis, and Crohn's disease.
21. Secukinumab (Cosentyx): A fully human monoclonal antibody that targets IL-17A, used in the treatment of psoriasis, psoriatic arthritis, and ankylosing spondylitis.
22. Ixekizumab (Taltz): A fully human monoclonal antibody that targets IL-17A, used in the treatment of psoriasis and psoriatic arthritis.
23. Brodalumab (Siliq): A fully human monoclonal antibody that targets IL-17 receptor A, used in the treatment of psoriasis.
24. Sarilumab (Kevzara): A fully human monoclonal antibody that targets the IL-6 receptor, used in the treatment of rheumatoid arthritis.
25. Tocilizumab (Actemra): A humanized monoclonal antibody that targets the IL-6 receptor, used in the treatment of rheumatoid arthritis, systemic juvenile idiopathic arthritis, polyarticular juvenile idiopathic arthritis, giant cell arteritis, and chimeric antigen receptor T-cell-induced cytokine release syndrome.
26. Siltuximab (Sylvant): A chimeric monoclonal antibody that targets IL-6, used in the treatment of multicentric Castleman disease.
27. Satralizumab (Enspryng): A humanized monoclonal antibody that targets IL-6 receptor alpha, used in the treatment of neuromyelitis optica spectrum disorder.
28. Sirukumab (Plivensia): A human monoclonal antibody that targets IL-6, used in the treatment

Adenosine triphosphatases (ATPases) are a group of enzymes that catalyze the conversion of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and inorganic phosphate. This reaction releases energy, which is used to drive various cellular processes such as muscle contraction, transport of ions across membranes, and synthesis of proteins and nucleic acids.

ATPases are classified into several types based on their structure, function, and mechanism of action. Some examples include:

1. P-type ATPases: These ATPases form a phosphorylated intermediate during the reaction cycle and are involved in the transport of ions across membranes, such as the sodium-potassium pump and calcium pumps.
2. F-type ATPases: These ATPases are found in mitochondria, chloroplasts, and bacteria, and are responsible for generating a proton gradient across the membrane, which is used to synthesize ATP.
3. V-type ATPases: These ATPases are found in vacuolar membranes and endomembranes, and are involved in acidification of intracellular compartments.
4. A-type ATPases: These ATPases are found in the plasma membrane and are involved in various functions such as cell signaling and ion transport.

Overall, ATPases play a crucial role in maintaining the energy balance of cells and regulating various physiological processes.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Sequence homology, amino acid, refers to the similarity in the order of amino acids in a protein or a portion of a protein between two or more species. This similarity can be used to infer evolutionary relationships and functional similarities between proteins. The higher the degree of sequence homology, the more likely it is that the proteins are related and have similar functions. Sequence homology can be determined through various methods such as pairwise alignment or multiple sequence alignment, which compare the sequences and calculate a score based on the number and type of matching amino acids.

An ovarian follicle is a fluid-filled sac in the ovary that contains an immature egg or ovum (oocyte). It's a part of the female reproductive system and plays a crucial role in the process of ovulation.

Ovarian follicles start developing in the ovaries during fetal development, but only a small number of them will mature and release an egg during a woman's reproductive years. The maturation process is stimulated by hormones like follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

There are different types of ovarian follicles, including primordial, primary, secondary, and tertiary or Graafian follicles. The Graafian follicle is the mature follicle that ruptures during ovulation to release the egg into the fallopian tube, where it may be fertilized by sperm.

It's important to note that abnormal growth or development of ovarian follicles can lead to conditions like polycystic ovary syndrome (PCOS) and ovarian cancer.

"Xenopus laevis" is not a medical term itself, but it refers to a specific species of African clawed frog that is often used in scientific research, including biomedical and developmental studies. Therefore, its relevance to medicine comes from its role as a model organism in laboratories.

In a broader sense, Xenopus laevis has contributed significantly to various medical discoveries, such as the understanding of embryonic development, cell cycle regulation, and genetic research. For instance, the Nobel Prize in Physiology or Medicine was awarded in 1963 to John R. B. Gurdon and Sir Michael J. Bishop for their discoveries concerning the genetic mechanisms of organism development using Xenopus laevis as a model system.

I'm sorry for any confusion, but "Thiones" is not a recognized medical term or abbreviation in physiology, pharmacology, or clinical medicine. It seems there might be a misunderstanding or a typo in your question. If you meant "thiols," I can provide a definition for that. Thiols are organic compounds containing a sulfhydryl group (-SH), which is a functional group consisting of a sulfur atom bonded to a hydrogen atom. Thiols are important in biological systems and can be found in some proteins and enzymes, where they play a crucial role in their structure and function. If you meant something else, please clarify so I can provide the most accurate information.

Gonads are the reproductive organs that produce gametes (sex cells) and sex hormones. In males, the gonads are the testes, which produce sperm and testosterone. In females, the gonads are the ovaries, which produce eggs and estrogen and progesterone. The development, function, and regulation of the gonads are crucial for reproductive health and fertility.

An allele is a variant form of a gene that is located at a specific position on a specific chromosome. Alleles are alternative forms of the same gene that arise by mutation and are found at the same locus or position on homologous chromosomes.

Each person typically inherits two copies of each gene, one from each parent. If the two alleles are identical, a person is said to be homozygous for that trait. If the alleles are different, the person is heterozygous.

For example, the ABO blood group system has three alleles, A, B, and O, which determine a person's blood type. If a person inherits two A alleles, they will have type A blood; if they inherit one A and one B allele, they will have type AB blood; if they inherit two B alleles, they will have type B blood; and if they inherit two O alleles, they will have type O blood.

Alleles can also influence traits such as eye color, hair color, height, and other physical characteristics. Some alleles are dominant, meaning that only one copy of the allele is needed to express the trait, while others are recessive, meaning that two copies of the allele are needed to express the trait.

A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.

Aurora Kinase A is a type of serine/threonine kinase that plays a crucial role in the regulation of cell division and mitosis. It is encoded by the AURKA gene in humans. This enzyme is responsible for proper chromosome alignment and segregation during mitosis, and its dysregulation has been implicated in various types of cancer. Aurora Kinase A is often overexpressed in cancer cells, leading to chromosomal instability and aneuploidy, which contribute to tumor growth and progression. Inhibitors of Aurora Kinase A are being investigated as potential cancer therapeutics.

Uridine is a nucleoside that consists of a pyrimidine base (uracil) linked to a pentose sugar (ribose). It is a component of RNA, where it pairs with adenine. Uridine can also be found in various foods such as beer, broccoli, yeast, and meat. In the body, uridine can be synthesized from orotate or from the breakdown of RNA. It has several functions, including acting as a building block for RNA, contributing to energy metabolism, and regulating cell growth and differentiation. Uridine is also available as a dietary supplement and has been studied for its potential benefits in various health conditions.

Tubulin modulators are a class of drugs that target and alter the function or structure of tubulin, which is a key component of microtubules in cells. These drugs can either stabilize or destabilize microtubules by interacting with tubulin, leading to various effects on cell division and other processes that rely on microtubule dynamics.

There are two main types of tubulin modulators:

1. Microtubule stabilizers: These drugs promote the assembly and stability of microtubules by binding to tubulin, preventing its disassembly. Examples include taxanes (e.g., paclitaxel) and vinca alkaloids (e.g., vinblastine). They are primarily used as anticancer agents because they interfere with the division of cancer cells.
2. Microtubule destabilizers: These drugs inhibit the formation and stability of microtubules by binding to tubulin, promoting its disassembly. Examples include colchicine, vinca alkaloids (e.g., vinorelbine), and combretastatins. They can also be used as anticancer agents because they disrupt the mitotic spindle during cell division, leading to cancer cell death.

Tubulin modulators have various other effects on cells beyond their impact on microtubules, such as interfering with intracellular transport and signaling pathways. These diverse actions contribute to their therapeutic potential in treating diseases like cancer, but they can also lead to side effects that limit their clinical use.

Protein transport, in the context of cellular biology, refers to the process by which proteins are actively moved from one location to another within or between cells. This is a crucial mechanism for maintaining proper cell function and regulation.

Intracellular protein transport involves the movement of proteins within a single cell. Proteins can be transported across membranes (such as the nuclear envelope, endoplasmic reticulum, Golgi apparatus, or plasma membrane) via specialized transport systems like vesicles and transport channels.

Intercellular protein transport refers to the movement of proteins from one cell to another, often facilitated by exocytosis (release of proteins in vesicles) and endocytosis (uptake of extracellular substances via membrane-bound vesicles). This is essential for communication between cells, immune response, and other physiological processes.

It's important to note that any disruption in protein transport can lead to various diseases, including neurological disorders, cancer, and metabolic conditions.

Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:

1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.

Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.

Colchicine is a medication that is primarily used to treat gout, a type of arthritis characterized by sudden and severe attacks of pain, swelling, redness, and tenderness in the joints. It works by reducing inflammation and preventing the formation of uric acid crystals that cause gout symptoms.

Colchicine is also used to treat familial Mediterranean fever (FMF), a genetic disorder that causes recurrent fevers and inflammation in the abdomen, chest, and joints. It can help prevent FMF attacks and reduce their severity.

The medication comes in the form of tablets or capsules that are taken by mouth. Common side effects of colchicine include diarrhea, nausea, vomiting, and abdominal pain. In rare cases, it can cause more serious side effects such as muscle weakness, nerve damage, and bone marrow suppression.

It is important to follow the dosage instructions carefully when taking colchicine, as taking too much of the medication can be toxic. People with certain health conditions, such as liver or kidney disease, may need to take a lower dose or avoid using colchicine altogether.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

I apologize for any confusion, but "plants" is not a term that has a medical definition. The term "plants" refers to a large and diverse group of organisms that obtain their energy through photosynthesis, which is the process of converting sunlight into chemical energy. Plants are typically characterized by having cells with cell walls containing cellulose, chloroplasts containing the pigment chlorophyll, and the ability to synthesize their own food through photosynthesis.

In a medical or biological context, you might be thinking of "plant-based" or "phytomedicine," which refer to the use of plants or plant extracts as a form of medicine or treatment. Phytomedicines have been used for thousands of years in many traditional systems of medicine, and some plant-derived compounds have been found to have therapeutic benefits in modern medicine as well. However, "plants" itself does not have a medical definition.

Myosin Type II, also known as myosin II or heavy meromyosin, is a type of motor protein involved in muscle contraction and other cellular movements. It is a hexameric protein composed of two heavy chains and four light chains. The heavy chains have a head domain that binds to actin filaments and an tail domain that forms a coiled-coil structure, allowing the formation of filaments. Myosin II uses the energy from ATP hydrolysis to move along actin filaments, generating force and causing muscle contraction or other cell movements. It plays a crucial role in various cellular processes such as cytokinesis, cell motility, and maintenance of cell shape.

Recombinases are enzymes that catalyze the process of recombination between two or more DNA molecules by breaking and rejoining their strands. They play a crucial role in various biological processes such as DNA repair, genetic recombination during meiosis, and site-specific genetic modifications.

Recombinases recognize and bind to specific DNA sequences, called recognition sites or crossover sites, where they cleave the phosphodiester bonds of the DNA backbone, forming a Holliday junction intermediate. The recombinase then catalyzes the exchange of strands between the two DNA molecules at the junction and subsequently ligates the broken ends to form new phosphodiester bonds, resulting in the recombination of the DNA molecules.

There are several types of recombinases, including serine recombinases, tyrosine recombinases, and lambda integrase. These enzymes differ in their recognition sites, catalytic mechanisms, and biological functions. Recombinases have important applications in molecular biology and genetic engineering, such as generating targeted DNA deletions or insertions, constructing genetic circuits, and developing gene therapy strategies.

Helminth proteins refer to the proteins that are produced and expressed by helminths, which are parasitic worms that cause diseases in humans and animals. These proteins can be found on the surface or inside the helminths and play various roles in their biology, such as in development, reproduction, and immune evasion. Some helminth proteins have been identified as potential targets for vaccines or drug development, as blocking their function may help to control or eliminate helminth infections. Examples of helminth proteins that have been studied include the antigen Bm86 from the cattle tick Boophilus microplus, and the tetraspanin protein Sm22.6 from the blood fluke Schistosoma mansoni.

I'm sorry for any confusion, but "grasshoppers" is not a term used in medical definitions. Grasshoppers are a type of insect that belongs to the order Orthoptera and suborder Caelifera. They are known for their long hind legs which they use for jumping, and some species can jump over 20 times their own body length. If you have any questions about medical terminology or topics, I'd be happy to help with those instead!

Pollen, in a medical context, refers to the fine powder-like substance produced by the male reproductive organ of seed plants. It contains microscopic grains known as pollen grains, which are transported by various means such as wind, water, or insects to the female reproductive organ of the same or another plant species for fertilization.

Pollen can cause allergic reactions in some individuals, particularly during the spring and summer months when plants release large amounts of pollen into the air. These allergies, also known as hay fever or seasonal allergic rhinitis, can result in symptoms such as sneezing, runny nose, congestion, itchy eyes, and coughing.

It is important to note that while all pollen has the potential to cause allergic reactions, certain types of plants, such as ragweed, grasses, and trees, are more likely to trigger symptoms in sensitive individuals.

RNA interference (RNAi) is a biological process in which RNA molecules inhibit the expression of specific genes. This process is mediated by small RNA molecules, including microRNAs (miRNAs) and small interfering RNAs (siRNAs), that bind to complementary sequences on messenger RNA (mRNA) molecules, leading to their degradation or translation inhibition.

RNAi plays a crucial role in regulating gene expression and defending against foreign genetic elements, such as viruses and transposons. It has also emerged as an important tool for studying gene function and developing therapeutic strategies for various diseases, including cancer and viral infections.

Proteins are complex, large molecules that play critical roles in the body's functions. They are made up of amino acids, which are organic compounds that are the building blocks of proteins. Proteins are required for the structure, function, and regulation of the body's tissues and organs. They are essential for the growth, repair, and maintenance of body tissues, and they play a crucial role in many biological processes, including metabolism, immune response, and cellular signaling. Proteins can be classified into different types based on their structure and function, such as enzymes, hormones, antibodies, and structural proteins. They are found in various foods, especially animal-derived products like meat, dairy, and eggs, as well as plant-based sources like beans, nuts, and grains.

Lamins are type V intermediate filament proteins that play a structural role in the nuclear envelope. They are the main components of the nuclear lamina, a mesh-like structure located inside the inner membrane of the nuclear envelope. Lamins are organized into homo- and heterodimers, which assemble into higher-order polymers to form the nuclear lamina. This structure provides mechanical support to the nucleus, helps maintain the shape and integrity of the nucleus, and plays a role in various nuclear processes such as DNA replication, transcription, and chromatin organization. Mutations in the genes encoding lamins have been associated with various human diseases, collectively known as laminopathies, which include muscular dystrophies, neuropathies, cardiomyopathies, and premature aging disorders.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

Medical Definition of "Multiprotein Complexes" :

Multiprotein complexes are large molecular assemblies composed of two or more proteins that interact with each other to carry out specific cellular functions. These complexes can range from relatively simple dimers or trimers to massive structures containing hundreds of individual protein subunits. They are formed through a process known as protein-protein interaction, which is mediated by specialized regions on the protein surface called domains or motifs.

Multiprotein complexes play critical roles in many cellular processes, including signal transduction, gene regulation, DNA replication and repair, protein folding and degradation, and intracellular transport. The formation of these complexes is often dynamic and regulated in response to various stimuli, allowing for precise control of their function.

Disruption of multiprotein complexes can lead to a variety of diseases, including cancer, neurodegenerative disorders, and infectious diseases. Therefore, understanding the structure, composition, and regulation of these complexes is an important area of research in molecular biology and medicine.

I'm sorry for any confusion, but "Marsupialia" is not a medical term. It is a taxonomic category in biology, specifically an order that includes mammals known as marsupials. These are mammals that carry their young in a pouch after birth. Examples of marsupials include kangaroos, koalas, and opossums. If you have any medical questions or terms you would like defined, I'd be happy to help!

Ataxia telangiectasia mutated (ATM) proteins are a type of protein that play a crucial role in the maintenance and repair of DNA in cells. The ATM gene produces these proteins, which are involved in several important cellular processes such as:

1. DNA damage response: When DNA is damaged, ATM proteins help to detect and respond to the damage by activating various signaling pathways that lead to DNA repair or apoptosis (programmed cell death) if the damage is too severe.
2. Cell cycle regulation: ATM proteins regulate the cell cycle by controlling checkpoints that ensure proper DNA replication and division. This helps prevent the propagation of cells with damaged DNA.
3. Telomere maintenance: ATM proteins help maintain telomeres, which are the protective caps at the ends of chromosomes. Telomeres shorten as cells divide, and when they become too short, cells can no longer divide and enter a state of senescence or die.

Mutations in the ATM gene can lead to Ataxia-telangiectasia (A-T), a rare inherited disorder characterized by neurological problems, immune system dysfunction, increased risk of cancer, and sensitivity to ionizing radiation. People with A-T have defective ATM proteins that cannot properly respond to DNA damage, leading to genomic instability and increased susceptibility to disease.

Carrier proteins, also known as transport proteins, are a type of protein that facilitates the movement of molecules across cell membranes. They are responsible for the selective and active transport of ions, sugars, amino acids, and other molecules from one side of the membrane to the other, against their concentration gradient. This process requires energy, usually in the form of ATP (adenosine triphosphate).

Carrier proteins have a specific binding site for the molecule they transport, and undergo conformational changes upon binding, which allows them to move the molecule across the membrane. Once the molecule has been transported, the carrier protein returns to its original conformation, ready to bind and transport another molecule.

Carrier proteins play a crucial role in maintaining the balance of ions and other molecules inside and outside of cells, and are essential for many physiological processes, including nerve impulse transmission, muscle contraction, and nutrient uptake.

'Staining and labeling' are techniques commonly used in pathology, histology, cytology, and molecular biology to highlight or identify specific components or structures within tissues, cells, or molecules. These methods enable researchers and medical professionals to visualize and analyze the distribution, localization, and interaction of biological entities, contributing to a better understanding of diseases, cellular processes, and potential therapeutic targets.

Medical definitions for 'staining' and 'labeling' are as follows:

1. Staining: A process that involves applying dyes or stains to tissues, cells, or molecules to enhance their contrast and reveal specific structures or components. Stains can be categorized into basic stains (which highlight acidic structures) and acidic stains (which highlight basic structures). Common staining techniques include Hematoxylin and Eosin (H&E), which differentiates cell nuclei from the surrounding cytoplasm and extracellular matrix; special stains, such as PAS (Periodic Acid-Schiff) for carbohydrates or Masson's trichrome for collagen fibers; and immunostains, which use antibodies to target specific proteins.
2. Labeling: A process that involves attaching a detectable marker or tag to a molecule of interest, allowing its identification, quantification, or tracking within a biological system. Labels can be direct, where the marker is directly conjugated to the targeting molecule, or indirect, where an intermediate linker molecule is used to attach the label to the target. Common labeling techniques include fluorescent labels (such as FITC, TRITC, or Alexa Fluor), enzymatic labels (such as horseradish peroxidase or alkaline phosphatase), and radioactive labels (such as ³²P or ¹⁴C). Labeling is often used in conjunction with staining techniques to enhance the specificity and sensitivity of detection.

Together, staining and labeling provide valuable tools for medical research, diagnostics, and therapeutic development, offering insights into cellular and molecular processes that underlie health and disease.

Phosphoprotein phosphatases (PPPs) are a family of enzymes that play a crucial role in the regulation of various cellular processes by removing phosphate groups from serine, threonine, and tyrosine residues on proteins. Phosphorylation is a post-translational modification that regulates protein function, localization, and stability, and dephosphorylation by PPPs is essential for maintaining the balance of this regulation.

The PPP family includes several subfamilies, such as PP1, PP2A, PP2B (also known as calcineurin), PP4, PP5, and PP6. Each subfamily has distinct substrate specificities and regulatory mechanisms. For example, PP1 and PP2A are involved in the regulation of metabolism, signal transduction, and cell cycle progression, while PP2B is involved in immune response and calcium signaling.

Dysregulation of PPPs has been implicated in various diseases, including cancer, neurodegenerative disorders, and cardiovascular disease. Therefore, understanding the function and regulation of PPPs is important for developing therapeutic strategies to target these diseases.

Confocal microscopy is a powerful imaging technique used in medical and biological research to obtain high-resolution, contrast-rich images of thick samples. This super-resolution technology provides detailed visualization of cellular structures and processes at various depths within a specimen.

In confocal microscopy, a laser beam focused through a pinhole illuminates a small spot within the sample. The emitted fluorescence or reflected light from this spot is then collected by a detector, passing through a second pinhole that ensures only light from the focal plane reaches the detector. This process eliminates out-of-focus light, resulting in sharp images with improved contrast compared to conventional widefield microscopy.

By scanning the laser beam across the sample in a raster pattern and collecting fluorescence at each point, confocal microscopy generates optical sections of the specimen. These sections can be combined to create three-dimensional reconstructions, allowing researchers to study cellular architecture and interactions within complex tissues.

Confocal microscopy has numerous applications in medical research, including studying protein localization, tracking intracellular dynamics, analyzing cell morphology, and investigating disease mechanisms at the cellular level. Additionally, it is widely used in clinical settings for diagnostic purposes, such as analyzing skin lesions or detecting pathogens in patient samples.

Okadaic acid is a type of toxin that is produced by certain species of marine algae, including Dinophysis and Prorocentrum. It is a potent inhibitor of protein phosphatases 1 and 2A, which are important enzymes that help regulate cellular processes in the body.

Okadaic acid can accumulate in shellfish that feed on these algae, and consumption of contaminated seafood can lead to a serious illness known as diarrhetic shellfish poisoning (DSP). Symptoms of DSP include nausea, vomiting, diarrhea, and abdominal cramps. In severe cases, it can also cause neurological symptoms such as dizziness, disorientation, and tingling or numbness in the lips, tongue, and fingers.

It is important to note that okadaic acid is not only a marine toxin but also used in scientific research as a tool to study the role of protein phosphatases in cellular processes. However, exposure to this compound should be avoided due to its toxic effects.

F-box proteins are a family of proteins that are characterized by the presence of an F-box domain, which is a motif of about 40-50 amino acids. This domain is responsible for binding to Skp1, a component of the SCF (Skp1-Cul1-F-box protein) E3 ubiquitin ligase complex. The F-box proteins serve as the substrate recognition subunit of this complex and are involved in targeting specific proteins for ubiquitination and subsequent degradation by the 26S proteasome.

There are multiple types of F-box proteins, including FBXW (also known as β-TrCP), FBXL, and FBLX, each with different substrate specificities. These proteins play important roles in various cellular processes such as cell cycle regulation, signal transduction, and DNA damage response by controlling the stability of key regulatory proteins.

Abnormal regulation of F-box proteins has been implicated in several human diseases, including cancer, developmental disorders, and neurodegenerative diseases.

Nuclear matrix-associated proteins (NMAPs) are a group of structural and functional proteins that are associated with the nuclear matrix, a network of fibers within the nucleus of a eukaryotic cell. The nuclear matrix provides support to the nuclear envelope and plays a role in DNA replication, transcription, and repair. NMAPs can be categorized into several groups based on their functions, including:

1. Scaffold proteins: These proteins provide structural support to the nuclear matrix and help maintain its architecture.
2. Enzymes: These proteins are involved in various biochemical reactions, such as DNA replication and repair, RNA processing, and chromatin remodeling.
3. Transcription factors: These proteins regulate gene expression by binding to specific DNA sequences and interacting with the transcription machinery.
4. Chromatin-associated proteins: These proteins are involved in the organization and regulation of chromatin structure and function.
5. Signal transduction proteins: These proteins transmit signals from the extracellular environment to the nucleus, regulating gene expression and other nuclear functions.

NMAPs have been implicated in various cellular processes, including cell cycle regulation, differentiation, apoptosis, and oncogenesis. Therefore, understanding the structure and function of NMAPs is crucial for elucidating the mechanisms underlying these processes and developing novel therapeutic strategies for various diseases, including cancer.

Karyotyping is a medical laboratory test used to study the chromosomes in a cell. It involves obtaining a sample of cells from a patient, usually from blood or bone marrow, and then staining the chromosomes so they can be easily seen under a microscope. The chromosomes are then arranged in pairs based on their size, shape, and other features to create a karyotype. This visual representation allows for the identification and analysis of any chromosomal abnormalities, such as extra or missing chromosomes, or structural changes like translocations or inversions. These abnormalities can provide important information about genetic disorders, diseases, and developmental problems.

Autoradiography is a medical imaging technique used to visualize and localize the distribution of radioactively labeled compounds within tissues or organisms. In this process, the subject is first exposed to a radioactive tracer that binds to specific molecules or structures of interest. The tissue is then placed in close contact with a radiation-sensitive film or detector, such as X-ray film or an imaging plate.

As the radioactive atoms decay, they emit particles (such as beta particles) that interact with the film or detector, causing chemical changes and leaving behind a visible image of the distribution of the labeled compound. The resulting autoradiogram provides information about the location, quantity, and sometimes even the identity of the molecules or structures that have taken up the radioactive tracer.

Autoradiography has been widely used in various fields of biology and medical research, including pharmacology, neuroscience, genetics, and cell biology, to study processes such as protein-DNA interactions, gene expression, drug metabolism, and neuronal connectivity. However, due to the use of radioactive materials and potential hazards associated with them, this technique has been gradually replaced by non-radioactive alternatives like fluorescence in situ hybridization (FISH) or immunofluorescence techniques.

Fungal DNA refers to the genetic material present in fungi, which are a group of eukaryotic organisms that include microorganisms such as yeasts and molds, as well as larger organisms like mushrooms. The DNA of fungi, like that of all living organisms, is made up of nucleotides that are arranged in a double helix structure.

Fungal DNA contains the genetic information necessary for the growth, development, and reproduction of fungi. This includes the instructions for making proteins, which are essential for the structure and function of cells, as well as other important molecules such as enzymes and nucleic acids.

Studying fungal DNA can provide valuable insights into the biology and evolution of fungi, as well as their potential uses in medicine, agriculture, and industry. For example, researchers have used genetic engineering techniques to modify the DNA of fungi to produce drugs, biofuels, and other useful products. Additionally, understanding the genetic makeup of pathogenic fungi can help scientists develop new strategies for preventing and treating fungal infections.

The Fluorescent Antibody Technique (FAT), Indirect is a type of immunofluorescence assay used to detect the presence of specific antigens in a sample. In this method, the sample is first incubated with a primary antibody that binds to the target antigen. After washing to remove unbound primary antibodies, a secondary fluorescently labeled antibody is added, which recognizes and binds to the primary antibody. This indirect labeling approach allows for amplification of the signal, making it more sensitive than direct methods. The sample is then examined under a fluorescence microscope to visualize the location and amount of antigen based on the emitted light from the fluorescent secondary antibody. It's commonly used in diagnostic laboratories for detection of various bacteria, viruses, and other antigens in clinical specimens.

A laser is not a medical term per se, but a physical concept that has important applications in medicine. The term "LASER" stands for "Light Amplification by Stimulated Emission of Radiation." It refers to a device that produces and amplifies light with specific characteristics, such as monochromaticity (single wavelength), coherence (all waves moving in the same direction), and high intensity.

In medicine, lasers are used for various therapeutic and diagnostic purposes, including surgery, dermatology, ophthalmology, and dentistry. They can be used to cut, coagulate, or vaporize tissues with great precision, minimizing damage to surrounding structures. Additionally, lasers can be used to detect and measure physiological parameters, such as blood flow and oxygen saturation.

It's important to note that while lasers are powerful tools in medicine, they must be used by trained professionals to ensure safe and effective treatment.

I'm sorry for any confusion, but "Protamine Kinase" is not a widely recognized or established term in medical or biological sciences. Protamines are small, arginine-rich proteins found in the sperm cells of many organisms, and they play a crucial role in the packaging and protection of DNA during spermatogenesis.

Kinases, on the other hand, are enzymes that catalyze the transfer of phosphate groups from ATP to specific amino acids in proteins, thereby modulating their function, localization, or stability.

A search of scientific literature reveals only a few instances where "protamine kinase" is mentioned, usually in the context of potential regulatory mechanisms during sperm maturation or fertilization. However, there is no widely accepted or well-characterized enzyme known as "protamine kinase." Therefore, it would be challenging to provide a concise and accurate medical definition for this term.

"Physarum" is not a term that has a specific medical definition. It is a genus of slime molds, which are single-celled organisms that can behave as multicellular entities under certain conditions. They are often studied in biological research for their unique behaviors and abilities, but they do not have direct relevance to human medicine.

Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).

The Western blotting procedure involves several steps:

1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.

Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.

Cytological techniques refer to the methods and procedures used to study individual cells, known as cytopathology. These techniques are used in the diagnosis and screening of various medical conditions, including cancer. The most common cytological technique is the Pap test, which involves collecting cells from the cervix and examining them for abnormalities. Other cytological techniques include fine-needle aspiration (FNA), which involves using a thin needle to withdraw cells from a tumor or lump, and body fluids analysis, which involves examining cells present in various bodily fluids such as urine, sputum, and pleural effusions. These techniques allow for the examination of cellular structure, morphology, and other characteristics to help diagnose and monitor diseases.

Genetically modified animals (GMAs) are those whose genetic makeup has been altered using biotechnological techniques. This is typically done by introducing one or more genes from another species into the animal's genome, resulting in a new trait or characteristic that does not naturally occur in that species. The introduced gene is often referred to as a transgene.

The process of creating GMAs involves several steps:

1. Isolation: The desired gene is isolated from the DNA of another organism.
2. Transfer: The isolated gene is transferred into the target animal's cells, usually using a vector such as a virus or bacterium.
3. Integration: The transgene integrates into the animal's chromosome, becoming a permanent part of its genetic makeup.
4. Selection: The modified cells are allowed to multiply, and those that contain the transgene are selected for further growth and development.
5. Breeding: The genetically modified individuals are bred to produce offspring that carry the desired trait.

GMAs have various applications in research, agriculture, and medicine. In research, they can serve as models for studying human diseases or testing new therapies. In agriculture, GMAs can be developed to exhibit enhanced growth rates, improved disease resistance, or increased nutritional value. In medicine, GMAs may be used to produce pharmaceuticals or other therapeutic agents within their bodies.

Examples of genetically modified animals include mice with added genes for specific proteins that make them useful models for studying human diseases, goats that produce a human protein in their milk to treat hemophilia, and pigs with enhanced resistance to certain viruses that could potentially be used as organ donors for humans.

It is important to note that the use of genetically modified animals raises ethical concerns related to animal welfare, environmental impact, and potential risks to human health. These issues must be carefully considered and addressed when developing and implementing GMA technologies.

Genetic transcription is the process by which the information in a strand of DNA is used to create a complementary RNA molecule. This process is the first step in gene expression, where the genetic code in DNA is converted into a form that can be used to produce proteins or functional RNAs.

During transcription, an enzyme called RNA polymerase binds to the DNA template strand and reads the sequence of nucleotide bases. As it moves along the template, it adds complementary RNA nucleotides to the growing RNA chain, creating a single-stranded RNA molecule that is complementary to the DNA template strand. Once transcription is complete, the RNA molecule may undergo further processing before it can be translated into protein or perform its functional role in the cell.

Transcription can be either "constitutive" or "regulated." Constitutive transcription occurs at a relatively constant rate and produces essential proteins that are required for basic cellular functions. Regulated transcription, on the other hand, is subject to control by various intracellular and extracellular signals, allowing cells to respond to changing environmental conditions or developmental cues.

In genetics, sequence alignment is the process of arranging two or more DNA, RNA, or protein sequences to identify regions of similarity or homology between them. This is often done using computational methods to compare the nucleotide or amino acid sequences and identify matching patterns, which can provide insight into evolutionary relationships, functional domains, or potential genetic disorders. The alignment process typically involves adjusting gaps and mismatches in the sequences to maximize the similarity between them, resulting in an aligned sequence that can be visually represented and analyzed.

DNA damage refers to any alteration in the structure or composition of deoxyribonucleic acid (DNA), which is the genetic material present in cells. DNA damage can result from various internal and external factors, including environmental exposures such as ultraviolet radiation, tobacco smoke, and certain chemicals, as well as normal cellular processes such as replication and oxidative metabolism.

Examples of DNA damage include base modifications, base deletions or insertions, single-strand breaks, double-strand breaks, and crosslinks between the two strands of the DNA helix. These types of damage can lead to mutations, genomic instability, and chromosomal aberrations, which can contribute to the development of diseases such as cancer, neurodegenerative disorders, and aging-related conditions.

The body has several mechanisms for repairing DNA damage, including base excision repair, nucleotide excision repair, mismatch repair, and double-strand break repair. However, if the damage is too extensive or the repair mechanisms are impaired, the cell may undergo apoptosis (programmed cell death) to prevent the propagation of potentially harmful mutations.

RNA (Ribonucleic Acid) is a single-stranded, linear polymer of ribonucleotides. It is a nucleic acid present in the cells of all living organisms and some viruses. RNAs play crucial roles in various biological processes such as protein synthesis, gene regulation, and cellular signaling. There are several types of RNA including messenger RNA (mRNA), ribosomal RNA (rRNA), transfer RNA (tRNA), small nuclear RNA (snRNA), microRNA (miRNA), and long non-coding RNA (lncRNA). These RNAs differ in their structure, function, and location within the cell.

DNA primers are short single-stranded DNA molecules that serve as a starting point for DNA synthesis. They are typically used in laboratory techniques such as the polymerase chain reaction (PCR) and DNA sequencing. The primer binds to a complementary sequence on the DNA template through base pairing, providing a free 3'-hydroxyl group for the DNA polymerase enzyme to add nucleotides and synthesize a new strand of DNA. This allows for specific and targeted amplification or analysis of a particular region of interest within a larger DNA molecule.

I'm happy to help! However, I believe there may be a slight mistake in your question. The abbreviation "cdc" is not typically associated with genetics or genes in the context of medical definitions.

If you meant to ask for a definition of "genes," here it is:

Genes are segments of DNA (deoxyribonucleic acid) that contain the instructions for the development, function, and reproduction of all living organisms. They are the basic units of heredity, passed down from one generation to the next. Genes encode specific proteins or RNA molecules that play critical roles in the structure, function, and regulation of the body's cells, tissues, and organs.

If you had a different term in mind, please let me know, and I will be happy to provide a definition for it!

Fungal genes refer to the genetic material present in fungi, which are eukaryotic organisms that include microorganisms such as yeasts and molds, as well as larger organisms like mushrooms. The genetic material of fungi is composed of DNA, just like in other eukaryotes, and is organized into chromosomes located in the nucleus of the cell.

Fungal genes are segments of DNA that contain the information necessary to produce proteins and RNA molecules required for various cellular functions. These genes are transcribed into messenger RNA (mRNA) molecules, which are then translated into proteins by ribosomes in the cytoplasm.

Fungal genomes have been sequenced for many species, revealing a diverse range of genes that encode proteins involved in various cellular processes such as metabolism, signaling, and regulation. Comparative genomic analyses have also provided insights into the evolutionary relationships among different fungal lineages and have helped to identify unique genetic features that distinguish fungi from other eukaryotes.

Understanding fungal genes and their functions is essential for advancing our knowledge of fungal biology, as well as for developing new strategies to control fungal pathogens that can cause diseases in humans, animals, and plants.

Inbred strains of mice are defined as lines of mice that have been brother-sister mated for at least 20 consecutive generations. This results in a high degree of homozygosity, where the mice of an inbred strain are genetically identical to one another, with the exception of spontaneous mutations.

Inbred strains of mice are widely used in biomedical research due to their genetic uniformity and stability, which makes them useful for studying the genetic basis of various traits, diseases, and biological processes. They also provide a consistent and reproducible experimental system, as compared to outbred or genetically heterogeneous populations.

Some commonly used inbred strains of mice include C57BL/6J, BALB/cByJ, DBA/2J, and 129SvEv. Each strain has its own unique genetic background and phenotypic characteristics, which can influence the results of experiments. Therefore, it is important to choose the appropriate inbred strain for a given research question.

Immunoelectron microscopy (IEM) is a specialized type of electron microscopy that combines the principles of immunochemistry and electron microscopy to detect and localize specific antigens within cells or tissues at the ultrastructural level. This technique allows for the visualization and identification of specific proteins, viruses, or other antigenic structures with a high degree of resolution and specificity.

In IEM, samples are first fixed, embedded, and sectioned to prepare them for electron microscopy. The sections are then treated with specific antibodies that have been labeled with electron-dense markers, such as gold particles or ferritin. These labeled antibodies bind to the target antigens in the sample, allowing for their visualization under an electron microscope.

There are several different methods of IEM, including pre-embedding and post-embedding techniques. Pre-embedding involves labeling the antigens before embedding the sample in resin, while post-embedding involves labeling the antigens after embedding. Post-embedding techniques are generally more commonly used because they allow for better preservation of ultrastructure and higher resolution.

IEM is a valuable tool in many areas of research, including virology, bacteriology, immunology, and cell biology. It can be used to study the structure and function of viruses, bacteria, and other microorganisms, as well as the distribution and localization of specific proteins and antigens within cells and tissues.

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

Haploidy is a term used in genetics to describe the condition of having half the normal number of chromosomes in a cell or an organism. In humans, for example, a haploid cell contains 23 chromosomes, whereas a diploid cell has 46 chromosomes.

Haploid cells are typically produced through a process called meiosis, which is a type of cell division that occurs in the reproductive organs of sexually reproducing organisms. During meiosis, a diploid cell undergoes two rounds of division to produce four haploid cells, each containing only one set of chromosomes.

In humans, haploid cells are found in the sperm and egg cells, which fuse together during fertilization to create a diploid zygote with 46 chromosomes. Haploidy is important for maintaining the correct number of chromosomes in future generations and preventing genetic abnormalities that can result from having too many or too few chromosomes.

Telomere-binding proteins are specialized proteins that bind to the telomeres, which are the repetitive DNA sequences found at the ends of chromosomes. These proteins play a crucial role in protecting the structural integrity and stability of chromosomes by preventing the degradation of telomeres during cell division and preventing the chromosomes from being recognized as damaged or broken.

One of the most well-known telomere-binding proteins is called TRF2 (telomeric repeat-binding factor 2), which helps to maintain the structure of the telomere "T-loop" and prevent the activation of DNA repair mechanisms that can lead to chromosomal instability. Another important telomere-binding protein is called POT1 (protection of telomeres 1), which specifically binds to the single-stranded overhang of the telomere and helps to regulate the activity of telomerase, an enzyme that adds DNA repeats to the ends of chromosomes during cell division.

Mutations in telomere-binding proteins have been linked to a variety of human diseases, including premature aging disorders, cancer, and bone marrow failure syndromes. Therefore, understanding the function and regulation of these proteins is an important area of research in molecular biology and genetics.

Chromosome aberrations refer to structural and numerical changes in the chromosomes that can occur spontaneously or as a result of exposure to mutagenic agents. These changes can affect the genetic material encoded in the chromosomes, leading to various consequences such as developmental abnormalities, cancer, or infertility.

Structural aberrations include deletions, duplications, inversions, translocations, and rings, which result from breaks and rearrangements of chromosome segments. Numerical aberrations involve changes in the number of chromosomes, such as aneuploidy (extra or missing chromosomes) or polyploidy (multiples of a complete set of chromosomes).

Chromosome aberrations can be detected and analyzed using various cytogenetic techniques, including karyotyping, fluorescence in situ hybridization (FISH), and comparative genomic hybridization (CGH). These methods allow for the identification and characterization of chromosomal changes at the molecular level, providing valuable information for genetic counseling, diagnosis, and research.

Arabidopsis proteins refer to the proteins that are encoded by the genes in the Arabidopsis thaliana plant, which is a model organism commonly used in plant biology research. This small flowering plant has a compact genome and a short life cycle, making it an ideal subject for studying various biological processes in plants.

Arabidopsis proteins play crucial roles in many cellular functions, such as metabolism, signaling, regulation of gene expression, response to environmental stresses, and developmental processes. Research on Arabidopsis proteins has contributed significantly to our understanding of plant biology and has provided valuable insights into the molecular mechanisms underlying various agronomic traits.

Some examples of Arabidopsis proteins include transcription factors, kinases, phosphatases, receptors, enzymes, and structural proteins. These proteins can be studied using a variety of techniques, such as biochemical assays, protein-protein interaction studies, and genetic approaches, to understand their functions and regulatory mechanisms in plants.

Cell polarity refers to the asymmetric distribution of membrane components, cytoskeleton, and organelles in a cell. This asymmetry is crucial for various cellular functions such as directed transport, cell division, and signal transduction. The plasma membrane of polarized cells exhibits distinct domains with unique protein and lipid compositions that define apical, basal, and lateral surfaces of the cell.

In epithelial cells, for example, the apical surface faces the lumen or external environment, while the basolateral surface interacts with other cells or the extracellular matrix. The establishment and maintenance of cell polarity are regulated by various factors including protein complexes, lipids, and small GTPases. Loss of cell polarity has been implicated in several diseases, including cancer and neurological disorders.

Aneuploidy is a medical term that refers to an abnormal number of chromosomes in a cell. Chromosomes are thread-like structures located inside the nucleus of cells that contain genetic information in the form of genes.

In humans, the normal number of chromosomes in a cell is 46, arranged in 23 pairs. Aneuploidy occurs when there is an extra or missing chromosome in one or more of these pairs. For example, Down syndrome is a condition that results from an extra copy of chromosome 21, also known as trisomy 21.

Aneuploidy can arise during the formation of gametes (sperm or egg cells) due to errors in the process of cell division called meiosis. These errors can result in eggs or sperm with an abnormal number of chromosomes, which can then lead to aneuploidy in the resulting embryo.

Aneuploidy is a significant cause of birth defects and miscarriages. The severity of the condition depends on which chromosomes are affected and the extent of the abnormality. In some cases, aneuploidy may have no noticeable effects, while in others it can lead to serious health problems or developmental delays.

Immunoblotting, also known as western blotting, is a laboratory technique used in molecular biology and immunogenetics to detect and quantify specific proteins in a complex mixture. This technique combines the electrophoretic separation of proteins by gel electrophoresis with their detection using antibodies that recognize specific epitopes (protein fragments) on the target protein.

The process involves several steps: first, the protein sample is separated based on size through sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Next, the separated proteins are transferred onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric field. The membrane is then blocked with a blocking agent to prevent non-specific binding of antibodies.

After blocking, the membrane is incubated with a primary antibody that specifically recognizes the target protein. Following this, the membrane is washed to remove unbound primary antibodies and then incubated with a secondary antibody conjugated to an enzyme such as horseradish peroxidase (HRP) or alkaline phosphatase (AP). The enzyme catalyzes a colorimetric or chemiluminescent reaction that allows for the detection of the target protein.

Immunoblotting is widely used in research and clinical settings to study protein expression, post-translational modifications, protein-protein interactions, and disease biomarkers. It provides high specificity and sensitivity, making it a valuable tool for identifying and quantifying proteins in various biological samples.

Gene silencing is a process by which the expression of a gene is blocked or inhibited, preventing the production of its corresponding protein. This can occur naturally through various mechanisms such as RNA interference (RNAi), where small RNAs bind to and degrade specific mRNAs, or DNA methylation, where methyl groups are added to the DNA molecule, preventing transcription. Gene silencing can also be induced artificially using techniques such as RNAi-based therapies, antisense oligonucleotides, or CRISPR-Cas9 systems, which allow for targeted suppression of gene expression in research and therapeutic applications.

Indole is not strictly a medical term, but it is a chemical compound that can be found in the human body and has relevance to medical and biological research. Indoles are organic compounds that contain a bicyclic structure consisting of a six-membered benzene ring fused to a five-membered pyrrole ring.

In the context of medicine, indoles are particularly relevant due to their presence in certain hormones and other biologically active molecules. For example, the neurotransmitter serotonin contains an indole ring, as does the hormone melatonin. Indoles can also be found in various plant-based foods, such as cruciferous vegetables (e.g., broccoli, kale), and have been studied for their potential health benefits.

Some indoles, like indole-3-carbinol and diindolylmethane, are found in these vegetables and can have anti-cancer properties by modulating estrogen metabolism, reducing inflammation, and promoting cell death (apoptosis) in cancer cells. However, it is essential to note that further research is needed to fully understand the potential health benefits and risks associated with indoles.

Cyclins are a family of regulatory proteins that play a crucial role in the cell cycle, which is the series of events that take place as a cell grows, divides, and produces two daughter cells. They are called cyclins because their levels fluctuate or cycle during the different stages of the cell cycle.

Cyclins function as subunits of serine/threonine protein kinase complexes, forming an active enzyme that adds phosphate groups to other proteins, thereby modifying their activity. This post-translational modification is a critical mechanism for controlling various cellular processes, including the regulation of the cell cycle.

There are several types of cyclins (A, B, D, and E), each of which is active during specific phases of the cell cycle:

1. Cyclin D: Expressed in the G1 phase, it helps to initiate the cell cycle by activating cyclin-dependent kinases (CDKs) that promote progression through the G1 restriction point.
2. Cyclin E: Active during late G1 and early S phases, it forms a complex with CDK2 to regulate the transition from G1 to S phase, where DNA replication occurs.
3. Cyclin A: Expressed in the S and G2 phases, it associates with both CDK2 and CDK1 to control the progression through the S and G2 phases and entry into mitosis (M phase).
4. Cyclin B: Active during late G2 and M phases, it partners with CDK1 to regulate the onset of mitosis by controlling the breakdown of the nuclear envelope, chromosome condensation, and spindle formation.

The activity of cyclins is tightly controlled through several mechanisms, including transcriptional regulation, protein degradation, and phosphorylation/dephosphorylation events. Dysregulation of cyclin expression or function can lead to uncontrolled cell growth and proliferation, which are hallmarks of cancer.

Polyploidy is a condition in which a cell or an organism has more than two sets of chromosomes, unlike the typical diploid state where there are only two sets (one from each parent). Polyploidy can occur through various mechanisms such as errors during cell division, fusion of egg and sperm cells that have an abnormal number of chromosomes, or through the reproduction process in plants.

Polyploidy is common in the plant kingdom, where it often leads to larger size, increased biomass, and sometimes hybrid vigor. However, in animals, polyploidy is less common and usually occurs in only certain types of cells or tissues, as most animals require a specific number of chromosomes for normal development and reproduction. In humans, polyploidy is typically not compatible with life and can lead to developmental abnormalities and miscarriage.

In mitotic prophase I of plants, this band disappears. Prophase I in meiosis is the most complex iteration of prophase that ... Meiosis involves two rounds of chromosome segregation and thus undergoes prophase twice, resulting in prophase I and prophase ... 99 Prophase II of meiosis is very similar to prophase of mitosis. The most noticeable difference is that prophase II occurs ... 98 Prophase II is very similar to mitotic prophase. Prophase I is divided into five phases: leptotene, zygotene, pachytene, ...
Prophase I-Prometaphase I.". Protoplasma. 108: 225-244. Hollyhock Rust: Puccinia malvacearum. University of Colorado Extension ...
It then stops in early prophase. Mammalian oocytes are maintained in meiotic prophase arrest for a very long time-months in ... However, although this process begins at prenatal age, it stops at prophase I. In late fetal life, all oocytes, still primary ... Meiosis I of ootidogenesis begins during embryonic development, but halts in the Diplotene stage of prophase I until puberty. ...
In plant cells only, prophase is preceded by a pre-prophase stage. In highly vacuolated plant cells, the nucleus has to migrate ... Early prophase: Polar microtubules, shown as green strands, have established a matrix around the currently intact nucleus, with ... Telophase: Reversal of prophase and prometaphase events and thus completing the cell cycle. Aneuploidy Binary fission ... Telophase (from the Greek word τελος meaning "end") is a reversal of prophase and prometaphase events. At telophase, the polar ...
Prophase is the first stage of division. The nuclear envelope is broken down in this stage, long strands of chromatin condense ...
It consists of microtubules and microfilaments (actin) and persists into prophase. Spindle formation occurs during prophase ... It precedes prophase and is characterized by two distinct events: The formation of the preprophase band, a dense microtubule ... This structure is called the prophase spindle. Triggered by nuclear membrane breakdown at the beginning of prometaphase, the ... During progression from preprophase into prophase, the randomly oriented microtubules align parallel along the nuclear surface ...
Mitosis also has prophase, but does not ordinarily do pairing of two homologous chromosomes. When the non-sister chromatids ... Synapsis takes place during prophase I of meiosis. When homologous chromosomes synapse, their ends are first attached to the ... UC Berkeley video of chromosome end migration and match assessment during prophase v t e (Articles with short description, ... Revenkova E, Jessberger R (2006). "Shaping meiotic prophase chromosomes: cohesins and synaptonemal complex proteins". ...
The role of STAG3 changes once prophase elapses. This is supported by the change in localization of STAG3 between metaphase and ... Much like the infertile STAG3 knockout male mice models, female mice also experienced meiotic arrest during prophase. Since ... Furthermore, STAG3 associates with axial elements during prophase, which are responsible for packaging the sister chromosomes ... causing the spermatocytes and oocytes to forgo meiosis upon reaching prophase. In STAG3 knockout cells, the presence of other ...
NDt80 is crucial for the completion of prophase and entry into meiosis 1, as it stimulates the expression of a large number of ... This event is triggered by the activation of M-Cdk in late prophase I. Then the spindle assembly checkpoint examines the ... Wee1 activity is high in early prophase I and the accumulation of Cdc25 activates M-Cdk by direct phosphorylation and marking ... In mouse oocytes CHEK1 appears to be indispensable for prophase I arrest and to function at the G2/M checkpoint. CHEK2 ...
Mitosis includes four phases: prophase, metaphase, anaphase, and telophase. Prophase is the initial phase when spindle fibers ...
After the successful completion of the G2 checkpoint, the final checkpoint in interphase, the cell proceeds to prophase, or in ... Prophase Prometaphase Metaphase Anaphase Telophase Cytoskeleton Marieb E (2000). Essentials of human anatomy and physiology. ... prophase is actually the first stage. In interphase, the cell gets itself ready for mitosis or meiosis. Somatic cells, or ...
ProPhase Precision Medicine, Inc., for about $14.6 million in a combination of ProPhase Labs common stock and cash. BGI Group ... "ProPhase Labs Acquires Whole Genome Sequencing Company, Nebula Genomics". Benzinga. 2021-08-11. Archived from the original on ... On 11 August 2021, ProPhase Labs, a diversified medical science and technology company, announced the acquisition of Nebula ...
Therefore, meiosis includes the stages of meiosis I (prophase I, metaphase I, anaphase I, telophase I) and meiosis II (prophase ... Prophase I is by far the longest phase of meiosis (lasting 13 out of 14 days in mice). During prophase I, homologous maternal ... prophase II, metaphase II, anaphase II, and telophase II. In prophase II, we see the disappearance of the nucleoli and the ... Prophase I is divided into a series of substages which are named according to the appearance of chromosomes. The first stage of ...
"Characterization of vertebrate cohesin complexes and their regulation in prophase". The Journal of Cell Biology. 151 (4): 749- ...
At prophase and metaphase, survivin is mainly nuclear in location. During prophase, as the chromatin condenses so that it is ...
"Characterization of vertebrate cohesin complexes and their regulation in prophase". The Journal of Cell Biology. 151 (4): 749- ...
"Characterization of vertebrate cohesin complexes and their regulation in prophase". J. Cell Biol. 151 (4): 749-62. doi:10.1083/ ...
Chromosome pairing and the lampbrush diplotene stage of meiotic prophase". Chromosoma (Berlin). 29 (3): 305-16. doi:10.1007/ ...
"Characterization of vertebrate cohesin complexes and their regulation in prophase". J. Cell Biol. 151 (4): 749-62. doi:10.1083/ ...
"Cohesin component dynamics during meiotic prophase I in mammalian oocytes". Chromosome Research. 12 (3): 197-213. doi:10.1023/B ...
"Characterization of vertebrate cohesin complexes and their regulation in prophase". J. Cell Biol. 151 (4): 749-62. doi:10.1083/ ...
Although this machinery is conserved through evolution, in vertebrates most cohesin molecules are released in prophase, ... avoiding their release during prophase. To be able to function as protector for the centromeric cohesion, Sgo1 must be ... "Characterization of vertebrate cohesin complexes and their regulation in prophase". The Journal of Cell Biology. 151 (4): 749- ...
"Characterization of Vertebrate Cohesin Complexes and Their Regulation in Prophase". J. Cell Biol. 151 (4): 749-62. doi:10.1083/ ...
During prophase, annexin XI will translocate to the nuclear envelope. Annexins are abundant in bone matrix vesicles, and are ...
They remain here until the meiotic prophase stage of meiosis. Here the spermatocytes pass through the basal membrane via the ...
"Characterization of Vertebrate Cohesin Complexes and Their Regulation in Prophase". J Cell Biol. 151 (4): 749-62. doi:10.1083/ ...
"Characterization of vertebrate cohesin complexes and their regulation in prophase". J. Cell Biol. 151 (4): 749-62. doi:10.1083/ ...
In 2005 a gene was identified (named Meisetz) that is required for progression through meiotic prophase and has H3K4 ... "A histone H3 methyltransferase controls epigenetic events required for meiotic prophase". Nature. 438 (7066): 374-8. Bibcode: ...
During telophase, the effects of prophase and prometaphase (the nucleolus and nuclear membrane disintegrating) are reversed. As ... Lamin subunits disassembled in prophase are inactivated and sequestered during mitosis. Lamina reassembly is triggered by lamin ... These components are dismantled during prophase and prometaphase and reconstructed during telophase, when the nuclear envelope ...
This led to their first recording of Sonic Portation (Prophase Music). YaHoWha13 made several appearances in Los Angeles and ...
In mitotic prophase I of plants, this band disappears. Prophase I in meiosis is the most complex iteration of prophase that ... Meiosis involves two rounds of chromosome segregation and thus undergoes prophase twice, resulting in prophase I and prophase ... 99 Prophase II of meiosis is very similar to prophase of mitosis. The most noticeable difference is that prophase II occurs ... 98 Prophase II is very similar to mitotic prophase. Prophase I is divided into five phases: leptotene, zygotene, pachytene, ...
A cell about to undergo mitosis
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ProPhase Labs, Applied DNA Sciences, Co-Diagnostics, HTG Molecular Diagnostics, OpGen, and Seegene reported quarterly financial ... ProPhase ended the quarter with $24.0 million in cash and cash equivalents and $3.5 million in marketable securities. ... ProPhase Labs on Thursday reported $29.1 million in revenues for the second quarter of 2022, up more than threefold from $9.1 ... Earnings Roundup: Cytek Biosciences, ProPhase Labs, Applied DNA Sciences, Co-Diagnostics, More Aug 12, 2022 , staff reporter ...
ProPhase Labs, Inc. (Formerly Known as Quigley Corporation) Establishes 2.5 Million Share Equity Line - read this article along ... About ProPhase Labs. ProPhase Labs is a diversified natural health medical science company. It is a leading marketer of the ... ProPhase Labs, Inc. (Formerly Known as Quigley Corporation) Establishes 2.5 Million Share Equity Line. Published: Nov 27, 2012 ... ProPhase Labs, Inc. (NASDAQ: PRPH) (www.ProPhaseLabs.com) announced today that on November 26, 2012, it entered into an ...
ProPhase/ProLevel. ProPhase and ProLevel are professional digital audio software tools that display detailed information of the ... phase (ProPhase only), levels, and mono compatibility of stereo audio signals in real time. ...
"A Wisp3 Cre-knockin Allele Produces Efficient Recombination in Spermatocytes during Early Prophase of Meiosis I." PLoS ONE 8 (9 ... A Wisp3 Cre-knockin Allele Produces Efficient Recombination in Spermatocytes during Early Prophase of Meiosis I. ... will be useful for studying early prophase of meiosis I and for efficiently recombining floxed alleles that are passed to ... where recombination in spermatocytes occurred by early prophase of meiosis I. As a consequence, males that were double ...
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Meiotic prophase I analysis in infertile Rad51cko/neo males. The left two columns represent control Rad51cneo/+ (neo/+) ... Meiotic prophase I analysis in infertile Rad51cko/neo males. The left two columns represent control Rad51cneo/+ (neo/+) ... S2 D). Overall in mutant Rad51cko/neo males, a shift in spermatocyte distribution toward early stages of prophase I was ... In ovaries of adult mice, oocytes are normally arrested in meiotic prophase I (Borum, 1961). As ovaries of the infertile Rad51c ...
Prophase➦. Prophase (from the Greek πρό, "before" and φάσις, "stage") is the first stage of cell division in both mitosis and ... Prophase vs. Metaphase - Whats the Difference?. Difference Between Prophase and Metaphase. ADVERTISEMENT ... Prophase➦. The first stage of meiosis, constituted by a series of events that include the thickening and coiling of the ... Prophase➦. The first stage of mitosis, during which the chromosomes condense and become visible, the nuclear membrane breaks ...
ProPhase Diagnostics is one of the elite nationwide CLIA laboratories. We offer some of the fastest PCR turnaround times in the ... At ProPhase, our customers always come first. With seamless on-boarding, user-friendly portal, and easy access to our ... ProPhase Labs, Inc.. 711 Stewart Avenue, Suite 200. Garden City, NY 11530 ...
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spermatocyte undergoing meiotic prophase I. TERM ID:. PLANA:0003245. ABOUT THIS TERM:. meiotic prophase I spermatocyte. ↳is a ... contains process meiotic prophase I. BROWSE PLANARIAN ONTOLOGY TREE (IN OLS):. Click on the - and + to collapse and expand ... meiotic prophase I spermatocyte. #outer { text-align: left; } .inner { display: inline-block; } Planarian Anatomy Ontology ...
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What Makes ProPhase Ltd. Stand Out. Author: ProPhase Ltd. , Oct 17, 2019 , Categories: Building Automation System , Data ... Author: ProPhase Ltd. , Dec 26, 2019 , Categories: Building Automation System , Data Network , Electrical Contracting Company ... Author: ProPhase Ltd. , Jun 12, 2019 , Categories: Building Automation System , Data Network , Electrical Contracting Company ... Author: ProPhase Ltd. , May 14, 2019 , Categories: Building Automation System , Data Network , Electrical Contracting Company ...
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Prophase I of meiosis I is a process that involves five different stages during which genetic material in the form of alleles ... Prophase I Glossary of Terms. In order to understand Prophase I of meiosis I, one should be familiar with the terms associated ... Prophase I is the first stage of meiosis I, followed by prophase II, anaphase I, anaphase II, metaphase I and metaphase II. ... Prophase I of meiosis I is a process that involves five different stages during which genetic material in the form of alleles ...
Karyokinesis further divided into prophase, metaphase, anaphase, and telophase. In the prophase, there is the arrangement of ... Mitosis - Definition, Prophase, Metaphase & More. February 21, 2021. September 24, 2020. by Nimar_geek ... Prophase. Throughout the interphase (non-dividing stage) of the cell cycle the chromosomes are not visible even with an ... In Prophase, animal cells have centrioles that arrange spindles while plant cells do not have centrioles. So, they have an ...
ProPhase Labs Inc. Stock Price, News and Company Updates. Message Board Total Posts: 30 ... ProPhase Labs Inc. (NASDAQ: PRPH) Company Website: http://www.prophaselabs.com/ ProPhase Labs Inc. (PRPH) Research Links. ... PRPH News Article - ProPhase Labs to Present at. whytestocks 10/18/2022 1:20:57 PM ... PRPH News Article - ProPhase Labs to Present at. whytestocks 09/06/2022 11:40:53 AM ...
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Prophase: A Present Tale by Mitchel Street. Discuss the November 2014 book of the month, Prophase: A Present Tale by Mitchel ... Featured Review: Prophase: A Present Tale by Mitchel Street Last post by Petronila O « 13 Feb 2022, 05:05. ... Surprises in Prophase (SPOILERS) Last post by Naval Aulakh « 09 Jul 2017, 06:49. ... Who is your favorite character in Prophase? (SPOILERS) Last post by Naval Aulakh « 09 Jul 2017, 06:47. ...
TaMSH7-3D is expressed in anthers during meiotic prophase I. To precisely determine TaMSH7-3D expression over the course of ... which is in agreement with a role of TaMSH7-3D in control of homoeologous recombination at meiotic prophase I (Fig. 4). TaMSH7- ... was observed between wild-type and ph1b anthers at prophase I (Supplementary Fig. 7). This data indicates that the absence of ... is expressed for the entirety of prophase, ...
... occur in which sub stages of prophase I ... Bouquet-stage occur in which sub stages of prophase I A. ... Which of the following events takes place during diplotene stage of prophase-I of meiosis? (a) Compaction of chromosomes (b) ...
About ProPhase Labs ProPhase Labs is a diversified natural health medical science company. It is a leading marketer and ... ProPhase Labs Reports Second Quarter 2010 Results. August 12, 2010 8:45am EDT Download as PDF ... ProPhase Labs has several wholly owned subsidiaries including a manufacturing unit, which consists of an FDA approved facility ... Effective Wednesday, August 11th, John DeShazo resigned from the Board of Directors of ProPhase Labs in order to be able to ...
ProPhase Labs on Wednesday announced that its subsidiary, ProPhase Precision Medicine, has signed a memorandum of understanding ... In addition, ProPhase and G42 will explore the possibility of collaborating on building an advanced genomics sequencing ... ProPhase, G42 Healthcare to collaborate on genomic sequencing, AI. LabPulse.com staff writers ... At USCAP 2023, ProPhase Labs to present data about esophageal cancer screening test. ...
  • The stage of mitosis and meiosis, following prophase and preceding anaphase, during which the chromosomes are aligned along the metaphase plate. (askdifference.com)
  • biology) The stage of mitosis and meiosis, that follows prophase and comes before anaphase, during which condensed chromosomes become aligned before being separated. (askdifference.com)
  • Prophase I is the first stage of meiosis I, followed by prophase II, anaphase I, anaphase II, metaphase I and metaphase II. (biologydictionary.net)
  • Karyokinesis can further be divided into prophase, metaphase, anaphase, and telophase for thorough understanding, though it is a constant process. (guyhowto.com)
  • Meiosis consists of two divisions, both of which follow the same stages as mitosis (prophase, metaphase, anaphase, telophase) Meiosis is preceded by interphase, in which DNA is replicated to produce chromosomes consisting of two sister chromatids. (replicadb4.com)
  • Mitosis includes prophase, prometaphase, metaphase, and anaphase, as well as telophase, during which chromosome copies are carefully separated in preparation for cytokinesis, where the cytoplasm divides. (coursehero.com)
  • Loss of HDAC8 activity results in increased SMC3 acetylation and inefficient dissolution of the 'used' cohesin complex released from chromatin in both prophase and anaphase. (nih.gov)
  • 2013. "A Wisp3 Cre-knockin Allele Produces Efficient Recombination in Spermatocytes during Early Prophase of Meiosis I." PLoS ONE 8 (9): e75116. (harvard.edu)
  • The only tissue that had high levels of Cre-mediated recombination was the testis, where recombination in spermatocytes occurred by early prophase of meiosis I. As a consequence, males that were double heterozygous for a Wisp3GFP-Cre and a floxed allele only contributed a recombined allele to their offspring. (harvard.edu)
  • We conclude that although WISP3 is dispensable in mice, male mice with a Wisp3GFP-Cre allele (Jackson Laboratory stock # 017685) will be useful for studying early prophase of meiosis I and for efficiently recombining floxed alleles that are passed to offspring. (harvard.edu)
  • Ameiotic1 ( Am1 ) encodes a plant-specific nuclear protein (AM1) required for meiotic entry and progression through early prophase I. Pollen mother cells (PMCs) remain mitotic in most am1 mutants including am1-489 , while am1-praI permits meiotic entry but PMCs arrest at the leptotene/zygotene (L/Z) transition, defining the roles of AM1 protein in two distinct steps of meiosis. (biomedcentral.com)
  • Our analysis of anther transcriptome modulations by two distinct am1 alleles, am1-489 and am1-praI , redefines the role of AM1 as a modulator of expression of a subset of meiotic genes, important for meiotic progression and provided stage-specific insights into the genetic networks associated with meiotic entry and early prophase I progression. (biomedcentral.com)
  • It then stops in early prophase. (wikipedia.org)
  • Silver staining, a more modern technology, in conjunction with giesma staining can be used to image the synaptonemal complex throughout the various stages of meiotic prophase. (wikipedia.org)
  • Meiotic prophase I is much longer that mitotic prophase. (replicadb4.com)
  • Mammalian oocytes are maintained in meiotic prophase arrest for a very long time-months in mice, years in humans. (wikipedia.org)
  • DOYLESTOWN, PA -- (MARKET WIRE) -- 08/12/10 -- ProPhase Labs, Inc. (NASDAQ: PRPH) today reported net sales of $1.1 million for the three months ended June 30, 2010, compared to net sales of $1.7 million for the three months ended June 30, 2009. (prophaselabs.com)
  • Garden City, NY, April 27, 2022 (GLOBE NEWSWIRE) -- ProPhase Labs, Inc. (NASDAQ: PRPH), a diversified diagnostics and genomics company, today announced that Chairman and CEO Ted Karkus will present. (globenewswire.com)
  • State-Of-The-Art COVID-19 Testing Available for 300,000 Residents to Aid Reopening Efforts GARDEN CITY, NY, May 06, 2021 (GLOBE NEWSWIRE) -- ProPhase Labs, Inc. (Nasdaq: PRPH), a diversified. (globenewswire.com)
  • ProPhase Labs on Thursday reported $29.1 million in revenues for the second quarter of 2022, up more than threefold from $9.1 million in the year-ago quarter. (genomeweb.com)
  • ProPhase Labs is a diversified natural health medical science company. (biospace.com)
  • ProPhase Labs has several wholly owned subsidiaries including a manufacturing unit, which consists of an FDA registered facility to manufacture Cold-EEZE® lozenges and fulfill other contract manufacturing opportunities. (biospace.com)
  • ProPhase Labs on Wednesday announced that its subsidiary, ProPhase Precision Medicine, has signed a memorandum of understanding (MOU) with G42 Healthcare to explore collaborative opportunities including genomic sequencing, artificial intelligence, sharing of genomic data insights, and obtaining certifications. (labpulse.com)
  • Prophase (from Ancient Greek προ- (pro-) 'before', and φάσις (phásis) 'appearance') is the first stage of cell division in both mitosis and meiosis. (wikipedia.org)
  • Meiosis involves two rounds of chromosome segregation and thus undergoes prophase twice, resulting in prophase I and prophase II. (wikipedia.org)
  • Prophase I is the most complex phase in all of meiosis because homologous chromosomes must pair and exchange genetic information. (wikipedia.org)
  • Many species arrest meiosis in diplotene of prophase I until ovulation. (wikipedia.org)
  • 98 In humans, decades can pass as oocytes remain arrested in prophase I only to quickly complete meiosis I prior to ovulation. (wikipedia.org)
  • Prophase (from the Greek πρό, "before" and φάσις, "stage") is the first stage of cell division in both mitosis and meiosis. (askdifference.com)
  • Prophase I of meiosis I is a process that involves five different stages during which genetic material in the form of alleles crosses over and recombines to form non-identical haploid chromatids. (biologydictionary.net)
  • In order to understand Prophase I of meiosis I, one should be familiar with the terms associated with this process. (biologydictionary.net)
  • At this first stage of Prophase I of meiosis I chromosomes are visible under electron microscopy and look like 'a string of beads', where the beads are referred to as nucleosomes. (biologydictionary.net)
  • What is the difference in prophase between mitosis and meiosis? (replicadb4.com)
  • What difference exists between the prophase of mitosis and prophase I of meiosis quizlet? (replicadb4.com)
  • D. Genetic material may be exchanged between chromosomes during prophase I of meiosis. (replicadb4.com)
  • Prophase 1 is the initial phase of meiosis 1 and prophase 2 is the initial phase of meiosis 2. (replicadb4.com)
  • What happens during the prophase I stage in meiosis? (replicadb4.com)
  • During prophase I, homologous chromosomes pair and form synapses, a step unique to meiosis. (replicadb4.com)
  • Which of the following statements best describes the major difference between prophase one of meiosis and prophase of mitosis? (replicadb4.com)
  • Which of the following statements best describes the major difference between prophase I of meiosis and prophase of mitosis? (replicadb4.com)
  • Which of the following differentiates prophase I of meiosis from prophase of mitosis? (replicadb4.com)
  • Which activities occurs in the prophase of meiosis but not in mitosis? (replicadb4.com)
  • What is the difference between prophase 1 and prophase 2 of meiosis? (replicadb4.com)
  • The key difference between prophase I and prophase II is that the prophase I is the beginning phase of meiosis I, and there is a long interphase before it while the prophase II is the first phase of meiosis II without an interphase prior to it. (replicadb4.com)
  • Various DNA stains are used to treat cells such that condensing chromosomes can be visualized as the move through prophase. (wikipedia.org)
  • During both meiotic and mitotic prophase, giemsa staining can be applied to cells to elicit G-banding in chromosomes. (wikipedia.org)
  • The main events of prophase are: the condensation of chromosomes, the movement of the centrosomes, the formation of the mitotic spindle, and the beginning of nucleoli break down. (wikipedia.org)
  • In addition to the events that occur in mitotic prophase, several crucial events occur within these phases such as pairing of homologous chromosomes and the reciprocal exchange of genetic material between these homologous chromosomes. (wikipedia.org)
  • In the first stage of prophase I, leptotene (from the Greek for "delicate"), chromosomes begin to condense. (wikipedia.org)
  • In the prophase, there is the arrangement of chromosomes from chromatin and mitotic apparatus. (guyhowto.com)
  • The chromatin product gets condensed by folding and the chromosomes appear as thin threads (0.25 mm - 50mm in length) at the beginning of prophase. (guyhowto.com)
  • During prophase I homologous chromosomes make contacts with each other called chiasmata and "crossing over" occurs….Memory Tricks. (replicadb4.com)
  • DNA condenses into chromosomes only during prophase of mitosis. (replicadb4.com)
  • In prophase I, tetrads of homologous chromosomes form and crossing over occurs. (replicadb4.com)
  • Each chromosome is condensed into a structure of two sister chromatids during prophase of mitosis. (coursehero.com)
  • The main occurrences in prophase are the condensation of the chromatin reticulum and the disappearance of the nucleolus. (wikipedia.org)
  • At the onset of prophase, chromatin condenses together into a highly ordered structure called a chromosome. (cikgunaza.com)
  • During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses. (replicadb4.com)
  • In the second quarter, we continued to feel the effects of both the retail overstock created by H1N1 related sales in late 2009 and the lower incidence of colds in Q1 and Q2 2010 compared to Q1 and Q2 2009," said ProPhase CEO Ted Karkus. (prophaselabs.com)
  • The goal of these initiatives is to advance and diversify our genomic sequencing capabilities while improving operational efficiencies," Ted Karkus, CEO of Prophase, said in a statement. (labpulse.com)
  • What is difference between prophase and prophase? (replicadb4.com)
  • What is the key difference between prophase and prophase one? (replicadb4.com)
  • The main difference between prophase 1 and 2 is that genetic recombination occurs through crossing overs and the "Chiasmata" formation during prophase 1 whereas no genetic recombination is noticed at the prophase 2. (replicadb4.com)
  • 98 Prophase II is very similar to mitotic prophase. (wikipedia.org)
  • Beginning after interphase, DNA has already been replicated when the cell enters prophase. (wikipedia.org)
  • At the start of prophase there are two identical copies of each chromosome in the cell due to replication in interphase. (wikipedia.org)
  • High-resolution chromosome analysis uses special culture methods to obtain a high percentage of prophase and prometaphase spreads. (msdmanuals.com)
  • The image below shows all five stages of Prophase I, starting with leptotene at the top. (biologydictionary.net)
  • ProPhase Diagnostics is one of the elite nationwide CLIA laboratories. (prophaselabs.com)
  • During prophase in animal cells, centrosomes move far enough apart to be resolved using a light microscope. (wikipedia.org)
  • In addition, ProPhase and G42 will explore the possibility of collaborating on building an advanced genomics sequencing facility as part of an expansion of ProPhase's headquarters in Garden City, NY, ProPhase added. (labpulse.com)
  • ProPhase Precision Medicine focuses on genomics testing technologies. (labpulse.com)
  • The ovum's development arrests in the prophase of the cell cycle until ovulation - this can occur many decades hence [AAP 2003]. (cdc.gov)
  • The majority of CDK2's known meiotic functions occur during prophase of the first meiotic division. (lu.se)
  • Prophase is the first phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells. (replicadb4.com)
  • Prophase I occurs at different speeds dependent on species and sex. (wikipedia.org)
  • ProPhase ended the quarter with $24.0 million in cash and cash equivalents and $3.5 million in marketable securities. (genomeweb.com)
  • Prophase is the first stage of mitosis in animal cells, and the second stage of mitosis in plant cells. (wikipedia.org)
  • ProPhase and ProLevel are professional digital audio software tools that display detailed information of the phase (ProPhase only), levels, and mono compatibility of stereo audio signals in real time. (katsurashareware.com)
  • What happens in the prophase phase? (replicadb4.com)