Cells in certain regions of an embryo that self-regulate embryonic development. These organizers have been found in dorsal and ventral poles of GASTRULA embryos, including Spemann organizer in amphibians, and Hensen node in chicken and mouse. These organizer cells communicate with each other via a network of secreted signaling proteins, such as BONE MORPHOGENETIC PROTEINS and their antagonists (chordin and noggin).
The chromosome region which is active in nucleolus formation and which functions in the synthesis of ribosomal RNA.
Goosecoid protein is a homeodomain protein that was first identified in XENOPUS. It is found in the SPEMANN ORGANIZER of VERTEBRATES and plays an important role in neuronal CELL DIFFERENTIATION and ORGANOGENESIS.
The processes occurring in early development that direct morphogenesis. They specify the body plan ensuring that cells will proceed to differentiate, grow, and diversify in size and shape at the correct relative positions. Included are axial patterning, segmentation, compartment specification, limb position, organ boundary patterning, blood vessel patterning, etc.
The complex processes of initiating CELL DIFFERENTIATION in the embryo. The precise regulation by cell interactions leads to diversity of cell types and specific pattern of organization (EMBRYOGENESIS).
The developmental stage that follows BLASTULA or BLASTOCYST. It is characterized by the morphogenetic cell movements including invagination, ingression, and involution. Gastrulation begins with the formation of the PRIMITIVE STREAK, and ends with the formation of three GERM LAYERS, the body plan of the mature organism.
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.
The use of silver, usually silver nitrate, as a reagent for producing contrast or coloration in tissue specimens.
The study of the development of an organism during the embryonic and fetal stages of life.
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.
A family of VERTEBRATE homeodomain proteins that share homology with orthodenticle protein, Drosophila. They regulate GENETIC TRANSCRIPTION and play an important role in EMBRYONIC DEVELOPMENT of the BRAIN.
The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.
Proteins obtained from the ZEBRAFISH. Many of the proteins in this species have been the subject of studies involving basic embryological development (EMBRYOLOGY).
Proteins encoded by homeobox genes (GENES, HOMEOBOX) that exhibit structural similarity to certain prokaryotic and eukaryotic DNA-binding proteins. Homeodomain proteins are involved in the control of gene expression during morphogenesis and development (GENE EXPRESSION REGULATION, DEVELOPMENTAL).
An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.
The middle germ layer of an embryo derived from three paired mesenchymal aggregates along the neural tube.
A fibroblast growth factor that preferentially activates FIBROBLAST GROWTH FACTOR RECEPTOR 4. It was initially identified as an androgen-induced growth factor and plays a role in regulating growth of human BREAST NEOPLASMS and PROSTATIC NEOPLASMS.
The founding member of the nodal signaling ligand family of proteins. Nodal protein was originally discovered in the region of the mouse embryo primitive streak referred to as HENSEN'S NODE. It is expressed asymmetrically on the left side in chordates and plays a critical role in the genesis of left-right asymmetry during vertebrate development.
The posterior of the three primitive cerebral vesicles of an embryonic brain. It consists of myelencephalon, metencephalon, and isthmus rhombencephali from which develop the major BRAIN STEM components, such as MEDULLA OBLONGATA from the myelencephalon, CEREBELLUM and PONS from the metencephalon, with the expanded cavity forming the FOURTH VENTRICLE.
A cartilaginous rod of mesodermal cells at the dorsal midline of all CHORDATE embryos. In lower vertebrates, notochord is the backbone of support. In the higher vertebrates, notochord is a transient structure, and segments of the vertebral column will develop around it. Notochord is also a source of midline signals that pattern surrounding tissues including the NEURAL TUBE development.
A genus of freshwater polyps in the family Hydridae, order Hydroida, class HYDROZOA. They are of special interest because of their complex organization and because their adult organization corresponds roughly to the gastrula of higher animals.
The middle of the three primitive cerebral vesicles of the embryonic brain. Without further subdivision, midbrain develops into a short, constricted portion connecting the PONS and the DIENCEPHALON. Midbrain contains two major parts, the dorsal TECTUM MESENCEPHALI and the ventral TEGMENTUM MESENCEPHALI, housing components of auditory, visual, and other sensorimoter systems.
In anatomy, 'axis' is a term used to describe a real or imaginary line around which something rotates or along which it aligns, such as the second cervical vertebra, also known as the axis bone, which provides the pivot point for the rotation of the head.
Members of the transforming growth factor superfamily that play a role in pattern formation and differentiation during the pregastrulation and GASTRULATION stages of chordate development. Several nodal signaling ligands are specifically involved in the genesis of left-right asymmetry during development. The protein group is named after a critical region of the vertebrate embryo PRIMITIVE STREAK referred to as HENSEN'S NODE.
An exotic species of the family CYPRINIDAE, originally from Asia, that has been introduced in North America. They are used in embryological studies and to study the effects of certain chemicals on development.
Regulatory proteins and peptides that are signaling molecules involved in the process of PARACRINE COMMUNICATION. They are generally considered factors that are expressed by one cell and are responded to by receptors on another nearby cell. They are distinguished from HORMONES in that their actions are local rather than distal.
Wnt proteins are a large family of secreted glycoproteins that play essential roles in EMBRYONIC AND FETAL DEVELOPMENT, and tissue maintenance. They bind to FRIZZLED RECEPTORS and act as PARACRINE PROTEIN FACTORS to initiate a variety of SIGNAL TRANSDUCTION PATHWAYS. The canonical Wnt signaling pathway stabilizes the transcriptional coactivator BETA CATENIN.
The upper part of the human body, or the front or upper part of the body of an animal, typically separated from the rest of the body by a neck, and containing the brain, mouth, and sense organs.
A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.
The outer of the three germ layers of an embryo.
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.
Bone-growth regulatory factors that are members of the transforming growth factor-beta superfamily of proteins. They are synthesized as large precursor molecules which are cleaved by proteolytic enzymes. The active form can consist of a dimer of two identical proteins or a heterodimer of two related bone morphogenetic proteins.
Transference of tissue within an individual, between individuals of the same species, or between individuals of different species.
The entire nerve apparatus, composed of a central part, the brain and spinal cord, and a peripheral part, the cranial and spinal nerves, autonomic ganglia, and plexuses. (Stedman, 26th ed)
A subclass of LIM domain proteins that include an additional centrally-located homeodomain region that binds AT-rich sites on DNA. Many LIM-homeodomain proteins play a role as transcriptional regulators that direct cell fate.
The development of anatomical structures to create the form of a single- or multi-cell organism. Morphogenesis provides form changes of a part, parts, or the whole organism.
Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.
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)
Genes that encode highly conserved TRANSCRIPTION FACTORS that control positional identity of cells (BODY PATTERNING) and MORPHOGENESIS throughout development. Their sequences contain a 180 nucleotide sequence designated the homeobox, so called because mutations of these genes often results in homeotic transformations, in which one body structure replaces another. The proteins encoded by homeobox genes are called HOMEODOMAIN PROTEINS.
A proto-oncogene protein and member of the Wnt family of proteins. It is expressed in the caudal MIDBRAIN and is essential for proper development of the entire mid-/hindbrain region.
Activins are produced in the pituitary, gonads, and other tissues. By acting locally, they stimulate pituitary FSH secretion and have diverse effects on cell differentiation and embryonic development. Activins are glycoproteins that are hetero- or homodimers of INHIBIN-BETA SUBUNITS.
Signaling ligands that act in opposition to NODAL PROTEIN. During vertebrate development they regulate the degree of left-right asymmetry by controlling the spatiotemporal influence of NODAL PROTEIN.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
The inner of the three germ layers of an embryo.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
The anterior portion of the developing hindbrain. It gives rise to the CEREBELLUM and the PONS.
An early non-mammalian embryo that follows the MORULA stage. A blastula resembles a hollow ball with the layer of cells surrounding a fluid-filled cavity (blastocele). The layer of cells is called BLASTODERM.
Proteins that are preferentially expressed or upregulated during FETAL DEVELOPMENT.
Proteins containing a region of conserved sequence, about 200 amino acids long, which encodes a particular sequence specific DNA binding domain (the T-box domain). These proteins are transcription factors that control developmental pathways. The prototype of this family is the mouse Brachyury (or T) gene product.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
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.
Conjoined twins are a rare type of monozygotic twinning where genetically identical individuals form a single organism with varying degrees of physical connection and shared anatomy due to incomplete division during embryonic development.
A family of small polypeptide growth factors that share several common features including a strong affinity for HEPARIN, and a central barrel-shaped core region of 140 amino acids that is highly homologous between family members. Although originally studied as proteins that stimulate the growth of fibroblasts this distinction is no longer a requirement for membership in the fibroblast growth factor family.
A layer of cells lining the fluid-filled cavity (blastocele) of a BLASTULA, usually developed from a fertilized insect, reptilian, or avian egg.
Proteins that bind to the MATRIX ATTACHMENT REGIONS of DNA.
A bone morphogenetic protein that is a potent inducer of bone formation. It also functions as a regulator of MESODERM formation during EMBRYONIC DEVELOPMENT.
The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.
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 silver salt with powerful germicidal activity. It has been used topically to prevent OPHTHALMIA NEONATORUM.
A multi-functional catenin that participates in CELL ADHESION and nuclear signaling. Beta catenin binds CADHERINS and helps link their cytoplasmic tails to the ACTIN in the CYTOSKELETON via ALPHA CATENIN. It also serves as a transcriptional co-activator and downstream component of WNT PROTEIN-mediated SIGNAL TRANSDUCTION PATHWAYS.
A forkhead transcription factor that regulates expression of metabolic GENES and is involved in EMBRYONIC DEVELOPMENT. Mutations in HNF-3beta have been associated with CONGENITAL HYPERINSULINISM.
VERTEBRATES belonging to the class amphibia such as frogs, toads, newts and salamanders that live in a semiaquatic environment.
A factor synthesized in a wide variety of tissues. It acts synergistically with TGF-alpha in inducing phenotypic transformation and can also act as a negative autocrine growth factor. TGF-beta has a potential role in embryonal development, cellular differentiation, hormone secretion, and immune function. TGF-beta is found mostly as homodimer forms of separate gene products TGF-beta1, TGF-beta2 or TGF-beta3. Heterodimers composed of TGF-beta1 and 2 (TGF-beta1.2) or of TGF-beta2 and 3 (TGF-beta2.3) have been isolated. The TGF-beta proteins are synthesized as precursor proteins.
Proteins which maintain the transcriptional quiescence of specific GENES or OPERONS. Classical repressor proteins are DNA-binding proteins that are normally bound to the OPERATOR REGION of an operon, or the ENHANCER SEQUENCES of a gene until a signal occurs that causes their release.
Glycoproteins that inhibit pituitary FOLLICLE STIMULATING HORMONE secretion. Inhibins are secreted by the Sertoli cells of the testes, the granulosa cells of the ovarian follicles, the placenta, and other tissues. Inhibins and ACTIVINS are modulators of FOLLICLE STIMULATING HORMONE secretions; both groups belong to the TGF-beta superfamily, as the TRANSFORMING GROWTH FACTOR BETA. Inhibins consist of a disulfide-linked heterodimer with a unique alpha linked to either a beta A or a beta B subunit to form inhibin A or inhibin B, respectively
The dorsal portion or roof of the midbrain which is composed of two pairs of bumps, the INFERIOR COLLICULI and the SUPERIOR COLLICULI. These four colliculi are also called the quadrigeminal bodies (TECTUM MESENCEPHALI). They are centers for visual sensorimotor integration.
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.
The region in the dorsal ECTODERM of a chordate embryo that gives rise to the future CENTRAL NERVOUS SYSTEM. Tissue in the neural plate is called the neuroectoderm, often used as a synonym of neural plate.
Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.
Containers, packaging, and packaging materials for drugs and BIOLOGICAL PRODUCTS. These include those in ampule, capsule, tablet, solution or other forms. Packaging includes immediate-containers, secondary-containers, and cartons. In the United States, such packaging is controlled under the Federal Food, Drug, and Cosmetic Act which also stipulates requirements for tamper-resistance and child-resistance. Similar laws govern use elsewhere. (From Code of Federal Regulations, 21 CFR 1 Section 210, 1993) DRUG LABELING is also available.
A family of intercellular signaling proteins that play and important role in regulating the development of many TISSUES and organs. Their name derives from the observation of a hedgehog-like appearance in DROSOPHILA embryos with genetic mutations that block their action.
The anterior of the three primitive cerebral vesicles of the embryonic brain arising from the NEURAL TUBE. It subdivides to form DIENCEPHALON and TELENCEPHALON. (Stedmans Medical Dictionary, 27th ed)
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 injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.
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.
Undifferentiated cells resulting from cleavage of a fertilized egg (ZYGOTE). Inside the intact ZONA PELLUCIDA, each cleavage yields two blastomeres of about half size of the parent cell. Up to the 8-cell stage, all of the blastomeres are totipotent. The 16-cell MORULA contains outer cells and inner cells.
'Nerve tissue proteins' are specialized proteins found within the nervous system's biological tissue, including neurofilaments, neuronal cytoskeletal proteins, and neural cell adhesion molecules, which facilitate structural support, intracellular communication, and synaptic connectivity essential for proper neurological function.
The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.
Animals having a vertebral column, members of the phylum Chordata, subphylum Craniata comprising mammals, birds, reptiles, amphibians, and fishes.
Phylum in the domain Eukarya, comprised of animals either with fully developed backbones (VERTEBRATES), or those with notochords only during some developmental stage (CHORDATA, NONVERTEBRATE).
A broadly distributed protein that binds directly to ACTIVINS. It functions as an activin antagonist, inhibits FOLLICLE STIMULATING HORMONE secretion, regulates CELL DIFFERENTIATION, and plays an important role in embryogenesis. Follistatin is a single glycosylated polypeptide chain of approximately 37-kDa and is not a member of the inhibin family (INHIBINS). Follistatin also binds and neutralizes many members of the TRANSFORMING GROWTH FACTOR BETA family.
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.
In anatomical terms, "tail" is not used as a medical definition to describe any part of the human body; it is however used in veterinary medicine to refer to the distal portion of the spine in animals possessing tails.
DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.
Genes that determine the fate of a cell or CELLS in a region of the embryo during EMBRYONIC DEVELOPMENT.
A portion of the animal phylum Chordata comprised of the subphyla CEPHALOCHORDATA; UROCHORDATA, and HYPEROTRETI, but not including the Vertebrata (VERTEBRATES). It includes nonvertebrate animals having a NOTOCHORD during some developmental stage.
Major constituent of the cytoskeleton found in the cytoplasm of eukaryotic cells. They form a flexible framework for the cell, provide attachment points for organelles and formed bodies, and make communication between parts of the cell possible.
A family of sequence-related proteins similar to HMGB1 PROTEIN that contains specific HMG-BOX DOMAINS.
Morphological and physiological development of EMBRYOS.
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.
The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)
A post-MORULA preimplantation mammalian embryo that develops from a 32-cell stage into a fluid-filled hollow ball of over a hundred cells. A blastocyst has two distinctive tissues. The outer layer of trophoblasts gives rise to extra-embryonic tissues. The inner cell mass gives rise to the embryonic disc and eventual embryo proper.
In a medical context, the term "wing" is not typically used as a standalone definition; however, it can refer to various flat, wing-shaped structures in anatomy, such as the iliac wings of the pelvis or the zygomatic wings of the cheekbone.
Transport proteins that carry specific substances in the blood or across cell membranes.
A family of CELL SURFACE RECEPTORS that bind BONE MORPHOGENETIC PROTEINS. They are PROTEIN-SERINE-THREONINE KINASES that mediate SIGNAL TRANSDUCTION PATHWAYS through SMAD PROTEINS.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
The developmental history of specific differentiated cell types as traced back to the original STEM CELLS in the embryo.
Common name for two distinct groups of BIRDS in the order GALLIFORMES: the New World or American quails of the family Odontophoridae and the Old World quails in the genus COTURNIX, family Phasianidae.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
Paired, segmented masses of MESENCHYME located on either side of the developing spinal cord (neural tube). Somites derive from PARAXIAL MESODERM and continue to increase in number during ORGANOGENESIS. Somites give rise to SKELETON (sclerotome); MUSCLES (myotome); and DERMIS (dermatome).
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
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.
A tube of ectodermal tissue in an embryo that will give rise to the CENTRAL NERVOUS SYSTEM, including the SPINAL CORD and the BRAIN. Lumen within the neural tube is called neural canal which gives rise to the central canal of the spinal cord and the ventricles of the brain. For malformation of the neural tube, see NEURAL TUBE DEFECTS.
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 paired box transcription factor that is essential for ORGANOGENESIS of the CENTRAL NERVOUS SYSTEM and KIDNEY.
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.
ANIMALS whose GENOME has been altered by GENETIC ENGINEERING, or their offspring.
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.
Mapping of the KARYOTYPE of a cell.
Time period from 1901 through 2000 of the common era.
Overall systems, traditional or automated, to provide medication to patients.
A congenital abnormality in which organs in the THORAX and the ABDOMEN are opposite to their normal positions (situs solitus) due to lateral transposition. Normally the STOMACH and SPLEEN are on the left, LIVER on the right, the three-lobed right lung is on the right, and the two-lobed left lung on the left. Situs inversus has a familial pattern and has been associated with a number of genes related to microtubule-associated proteins.
The fertilized OVUM resulting from the fusion of a male and a female gamete.
A fibroblast growth factor that is expressed primarily during development.
A complex signaling pathway whose name is derived from the DROSOPHILA Wg gene, which when mutated results in the wingless phenotype, and the vertebrate INT gene, which is located near integration sites of MOUSE MAMMARY TUMOR VIRUS. The signaling pathway is initiated by the binding of WNT PROTEINS to cells surface WNT RECEPTORS which interact with the AXIN SIGNALING COMPLEX and an array of second messengers that influence the actions of BETA CATENIN.
A flavanone glycoside found in CITRUS fruit peels.
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.
The field of biology which deals with the process of the growth and differentiation of an organism.
Products of proto-oncogenes. Normally they do not have oncogenic or transforming properties, but are involved in the regulation or differentiation of cell growth. They often have protein kinase activity.
Proteins obtained from species of BIRDS.
Factors that form a preinitiation complex at promoters that are specifically transcribed by RNA POLYMERASE I.
A subclass of SOX transcription factors that are expressed in neuronal tissue where they may play a role in the regulation of CELL DIFFERENTIATION. Members of this subclass are generally considered to be transcriptional activators.
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
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.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
A disorder of the skin, the oral mucosa, and the gingiva, that usually presents as a solitary polypoid capillary hemangioma often resulting from trauma. It is manifested as an inflammatory response with similar characteristics to those of a granuloma.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
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.
The paired caudal parts of the PROSENCEPHALON from which the THALAMUS; HYPOTHALAMUS; EPITHALAMUS; and SUBTHALAMUS are derived.
Methods of maintaining or growing biological materials in controlled laboratory conditions. These include the cultures of CELLS; TISSUES; organs; or embryo in vitro. Both animal and plant tissues may be cultured by a variety of methods. Cultures may derive from normal or abnormal tissues, and consist of a single cell type or mixed cell types.
A bioflavonoid that strengthens vascular walls.
The three primary germinal layers (ECTODERM; ENDODERM; and MESODERM) developed during GASTRULATION that provide tissues and body plan of a mature organism. They derive from two early layers, hypoblast and epiblast.
A family of seven-pass transmembrane cell-surface proteins that combines with LOW DENSITY LIPROTEIN RECEPTOR-RELATED PROTEIN-5 or LOW DENSITY LIPROTEIN RECEPTOR-RELATED PROTEIN-5 to form receptors for WNT PROTEINS. Frizzled receptors often couple with HETEROTRIMERIC G PROTEINS and regulate the WNT SIGNALING PATHWAY.
Trans-acting protein that combines with host factors to induce immediate early gene transcription in herpes simplex virus.

Embryonic organizers are specialized cells or tissues in developing embryos that provide critical signals to guide the organization and development of surrounding cells and tissues. They play a crucial role in establishing the body plan and patterning of the organism during embryogenesis. A well-known example is the Spemann-Mangold organizer, first described in amphibians, which induces the formation of the neural tissue and organizes the surrounding tissues to form the body axis. Embryonic organizers have been identified in various animal models, including mammals, birds, and fish, and they are essential for normal embryonic development.

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.

Goosecoid protein is not a term that has a specific medical definition. However, it is a biological term related to the field of developmental biology and genetics.

Goosecoid protein is a transcription factor that plays a crucial role in embryonic development, particularly during gastrulation - an early stage of embryogenesis where the three germ layers (ectoderm, mesoderm, and endoderm) are formed. The goosecoid gene encodes this protein, and it is primarily expressed in the Spemann-Mangold organizer, a structure located in the dorsal blastopore lip of amphibian embryos. This organizer region is essential for establishing the body axis and inducing the formation of the central nervous system.

In humans, goosecoid protein homologs have been identified, and they are involved in various developmental processes, including limb development and craniofacial morphogenesis. Dysregulation of goosecoid protein expression or function has been implicated in several congenital disorders and cancer types. However, a direct medical definition focusing on 'Goosecoid Protein' is not available due to its broader biological context.

"Body patterning" is a general term that refers to the process of forming and organizing various tissues and structures into specific patterns during embryonic development. This complex process involves a variety of molecular mechanisms, including gene expression, cell signaling, and cell-cell interactions. It results in the creation of distinct body regions, such as the head, trunk, and limbs, as well as the organization of internal organs and systems.

In medical terminology, "body patterning" may refer to specific developmental processes or abnormalities related to embryonic development. For example, in genetic disorders such as Poland syndrome or Holt-Oram syndrome, mutations in certain genes can lead to abnormal body patterning, resulting in the absence or underdevelopment of certain muscles, bones, or other structures.

It's important to note that "body patterning" is not a formal medical term with a specific definition, but rather a general concept used in developmental biology and genetics.

Embryonic induction is a process that occurs during the development of a multicellular organism, where one group of cells in the embryo signals and influences the developmental fate of another group of cells. This interaction leads to the formation of specific structures or organs in the developing embryo. The signaling cells that initiate the process are called organizers, and they release signaling molecules known as morphogens that bind to receptors on the target cells and trigger a cascade of intracellular signals that ultimately lead to changes in gene expression and cell fate. Embryonic induction is a crucial step in the development of complex organisms and plays a key role in establishing the body plan and organizing the different tissues and organs in the developing embryo.

A gastrula is a stage in the early development of many animals, including humans, that occurs following fertilization and cleavage of the zygote. During this stage, the embryo undergoes a process called gastrulation, which involves a series of cell movements that reorganize the embryo into three distinct layers: the ectoderm, mesoderm, and endoderm. These germ layers give rise to all the different tissues and organs in the developing organism.

The gastrula is characterized by the presence of a central cavity called the archenteron, which will eventually become the gut or gastrointestinal tract. The opening of the archenteron is called the blastopore, which will give rise to either the mouth or anus, depending on the animal group.

In summary, a gastrula is a developmental stage in which an embryo undergoes gastrulation to form three germ layers and a central cavity, which will eventually develop into various organs and tissues of the body.

"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.

"Silver staining" is a histological term that refers to a technique used to selectively stain various components of biological tissues, making them more visible under a microscope. This technique is often used in the study of histopathology and cytology. The most common type of silver staining is known as "silver impregnation," which is used to demonstrate the presence of argyrophilic structures, such as nerve fibers and neurofibrillary tangles, in tissues.

The process of silver staining involves the use of silver salts, which are reduced by a developer to form metallic silver that deposits on the tissue components. The intensity of the stain depends on the degree of reduction of the silver ions, and it can be modified by adjusting the concentration of the silver salt, the development time, and other factors.

Silver staining is widely used in diagnostic pathology to highlight various structures such as nerve fibers, axons, collagen, basement membranes, and microorganisms like fungi and bacteria. It has also been used in research to study the distribution and organization of these structures in tissues. However, it's important to note that silver staining is not specific for any particular substance, so additional tests are often needed to confirm the identity of the stained structures.

Embryology is the branch of biology that deals with the formation, growth, and development of an embryo. It is a scientific study that focuses on the structural and functional changes that occur during the development of a fertilized egg or zygote into a mature organism. Embryologists study the various stages of embryonic development, including gametogenesis (the formation of sperm and eggs), fertilization, cleavage, gastrulation, neurulation, and organogenesis. They also investigate the genetic and environmental factors that influence embryonic development and may use this information to understand and prevent birth defects and other developmental abnormalities.

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.

OTX (Orthodenticle homeobox) transcription factors are a family of proteins that regulate gene expression during embryonic development, particularly in the eye, forebrain, and midbrain. They play crucial roles in the development and differentiation of these tissues, including the specification of eye field identity, the determination of dorsoventral patterning in the neural tube, and the regulation of neurogenesis.

OTX transcription factors contain a highly conserved DNA-binding domain called the homeodomain, which allows them to recognize and bind to specific DNA sequences. In humans, there are four known OTX transcription factors (OTX1, OTX2, OTX3, and CRX), each with distinct expression patterns and functions.

Mutations in OTX genes have been associated with various developmental disorders, such as microphthalmia, anophthalmia, and severe eye malformations, highlighting their importance in normal eye development. Additionally, OTX transcription factors have also been implicated in the pathogenesis of certain cancers, including medulloblastoma and retinoblastoma.

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.

Zebrafish proteins refer to the diverse range of protein molecules that are produced by the organism Danio rerio, commonly known as the zebrafish. These proteins play crucial roles in various biological processes such as growth, development, reproduction, and response to environmental stimuli. They are involved in cellular functions like enzymatic reactions, signal transduction, structural support, and regulation of gene expression.

Zebrafish is a popular model organism in biomedical research due to its genetic similarity with humans, rapid development, and transparent embryos that allow for easy observation of biological processes. As a result, the study of zebrafish proteins has contributed significantly to our understanding of protein function, structure, and interaction in both zebrafish and human systems.

Some examples of zebrafish proteins include:

* Transcription factors that regulate gene expression during development
* Enzymes involved in metabolic pathways
* Structural proteins that provide support to cells and tissues
* Receptors and signaling molecules that mediate communication between cells
* Heat shock proteins that assist in protein folding and protect against stress

The analysis of zebrafish proteins can be performed using various techniques, including biochemical assays, mass spectrometry, protein crystallography, and computational modeling. These methods help researchers to identify, characterize, and understand the functions of individual proteins and their interactions within complex networks.

Homeodomain proteins are a group of transcription factors that play crucial roles in the development and differentiation of cells in animals and plants. They are characterized by the presence of a highly conserved DNA-binding domain called the homeodomain, which is typically about 60 amino acids long. The homeodomain consists of three helices, with the third helix responsible for recognizing and binding to specific DNA sequences.

Homeodomain proteins are involved in regulating gene expression during embryonic development, tissue maintenance, and organismal growth. They can act as activators or repressors of transcription, depending on the context and the presence of cofactors. Mutations in homeodomain proteins have been associated with various human diseases, including cancer, congenital abnormalities, and neurological disorders.

Some examples of homeodomain proteins include PAX6, which is essential for eye development, HOX genes, which are involved in body patterning, and NANOG, which plays a role in maintaining pluripotency in stem cells.

"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.

In medical and embryological terms, the mesoderm is one of the three primary germ layers in the very early stages of embryonic development. It forms between the ectoderm and endoderm during gastrulation, and it gives rise to a wide variety of cell types, tissues, and organs in the developing embryo.

The mesoderm contributes to the formation of structures such as:

1. The connective tissues (including tendons, ligaments, and most of the bones)
2. Muscular system (skeletal, smooth, and cardiac muscles)
3. Circulatory system (heart, blood vessels, and blood cells)
4. Excretory system (kidneys and associated structures)
5. Reproductive system (gonads, including ovaries and testes)
6. Dermis of the skin
7. Parts of the eye and inner ear
8. Several organs in the urogenital system

Dysfunctions or abnormalities in mesoderm development can lead to various congenital disorders and birth defects, highlighting its importance during embryogenesis.

Fibroblast Growth Factor 8 (FGF-8) is a growth factor that belongs to the fibroblast growth factor family. It plays crucial roles in various biological processes, including embryonic development, tissue repair, and cancer progression. Specifically, FGF-8 has been implicated in the regulation of cell proliferation, differentiation, migration, and survival.

During embryonic development, FGF-8 is involved in the formation of the nervous system, limbs, and other organs. It acts as a signaling molecule that helps to establish patterns of gene expression and cell behavior during development. In tissue repair, FGF-8 can stimulate the proliferation and migration of cells involved in wound healing, such as fibroblasts and endothelial cells.

In cancer, FGF-8 has been shown to promote tumor growth, angiogenesis (the formation of new blood vessels), and metastasis. It can do this by activating signaling pathways that promote cell proliferation, survival, and migration. Overexpression of FGF-8 has been found in various types of cancer, including breast, lung, prostate, and ovarian cancer.

In summary, Fibroblast Growth Factor 8 (FGF-8) is a signaling molecule that plays important roles in embryonic development, tissue repair, and cancer progression by regulating cell proliferation, differentiation, migration, and survival.

A nodal protein, in the context of molecular biology and genetics, refers to a protein that plays a role in signal transmission within a cell at a node or junction point of a signaling pathway. These proteins are often involved in regulatory processes, such as activating or inhibiting downstream effectors in response to specific signals received by the cell. Nodal proteins can be activated or deactivated through various mechanisms, including phosphorylation, ubiquitination, and interactions with other signaling molecules.

In a more specific context, nodal proteins are also known as nodal factors, which are members of the transforming growth factor-beta (TGF-β) superfamily of signaling molecules that play critical roles in embryonic development and tissue homeostasis. Nodal is a secreted protein that acts as a morphogen, inducing different cellular responses depending on its concentration gradient. It is involved in establishing left-right asymmetry during embryonic development and regulates various processes such as cell proliferation, differentiation, and apoptosis.

In summary, nodal proteins can refer to any protein that functions at a node or junction point of a signaling pathway, but they are also specifically known as nodal factors, which are TGF-β superfamily members involved in embryonic development and tissue homeostasis.

The rhombencephalon is a term used in the field of neuroanatomy, which refers to the most posterior region of the developing brain during embryonic development. It is also known as the hindbrain and it gives rise to several important structures in the adult brain.

More specifically, the rhombencephalon can be further divided into two main parts: the metencephalon and the myelencephalon. The metencephalon eventually develops into the pons and cerebellum, while the myelencephalon becomes the medulla oblongata.

The rhombencephalon plays a crucial role in several critical functions of the nervous system, including regulating heart rate and respiration, maintaining balance and posture, and coordinating motor movements. Defects or abnormalities in the development of the rhombencephalon can lead to various neurological disorders, such as cerebellar hypoplasia, Chiari malformation, and certain forms of brainstem tumors.

The notochord is a flexible, rod-shaped structure that is present in the embryos of chordates, including humans. It is composed of cells called chordocytes and is surrounded by a sheath. The notochord runs along the length of the body, providing support and flexibility. In human embryos, the notochord eventually becomes part of the discs between the vertebrae in the spine. An abnormal or absent notochord can lead to developmental problems with the spine and nervous system.

I'm sorry for any confusion, but "Hydra" is not a term commonly used in medical definitions. Hydra is a genus of small, simple aquatic animals, belonging to the class Hydrozoa in the phylum Cnidaria. They are named after the multi-headed creature from Greek mythology due to their ability to regenerate lost body parts.

If you're looking for a medical term related to hydra, one possibility could be "Hydralazine," which is a medication used to treat high blood pressure. It works by relaxing the muscle in the walls of blood vessels, causing them to widen and the blood to flow more easily.

I hope this information is helpful! If you have any other questions or need clarification on a different topic, please let me know.

The mesencephalon, also known as the midbrain, is the middle portion of the brainstem that connects the hindbrain (rhombencephalon) and the forebrain (prosencephalon). It plays a crucial role in several important functions including motor control, vision, hearing, and the regulation of consciousness and sleep-wake cycles. The mesencephalon contains several important structures such as the cerebral aqueduct, tectum, tegmentum, cerebral peduncles, and several cranial nerve nuclei (III and IV).

In medical terms, "axis" is used to describe a line or lines along which a structure or body part can move or around which it is oriented. It is often used in anatomical context to refer to specific axes of movement or alignment for various parts of the body. For example:

* The axial skeleton, also known as the upright skeleton, includes the skull, vertebral column, and chest cage.
* In neurology, the term "axis" is used to describe the second cervical vertebra (C2), which is also called the axis because it serves as a pivot point for head movement.
* The term "longitudinal axis" is used to describe an imaginary line that runs from the head to the foot, passing through the center of the body.
* In imaging studies such as X-rays or MRIs, the term "axis" may be used to describe a specific orientation or alignment for the image.

Overall, the term "axis" is used in medicine to describe lines or planes that serve as reference points for movement, alignment, or orientation of various body structures and parts.

Nodal signaling ligands refer to a group of proteins that play a crucial role in the developmental processes of organisms, particularly during embryogenesis. Nodal is a member of the transforming growth factor-beta (TGF-β) superfamily and functions as a key morphogen in establishing left-right asymmetry, inducing mesoderm formation, and promoting cell differentiation and proliferation.

Nodal signals are transmitted through a complex network of intracellular signaling pathways involving type I and type II receptors, regulatory Smad proteins (Smad2 and Smad3), and co-activators or co-repressors. The activation of Nodal signaling ligands is tightly regulated both spatially and temporally to ensure proper embryonic development.

Abnormalities in Nodal signaling have been implicated in various human congenital disorders, such as heterotaxy syndrome, which affects the normal asymmetry of internal organs. Additionally, deregulated Nodal signaling has also been associated with certain types of cancer, including ovarian and colorectal cancers.

A zebrafish is a freshwater fish species belonging to the family Cyprinidae and the genus Danio. Its name is derived from its distinctive striped pattern that resembles a zebra's. Zebrafish are often used as model organisms in scientific research, particularly in developmental biology, genetics, and toxicology studies. They have a high fecundity rate, transparent embryos, and a rapid development process, making them an ideal choice for researchers. However, it is important to note that providing a medical definition for zebrafish may not be entirely accurate or relevant since they are primarily used in biological research rather than clinical medicine.

Intercellular signaling peptides and proteins are molecules that mediate communication and interaction between different cells in living organisms. They play crucial roles in various biological processes, including cell growth, differentiation, migration, and apoptosis (programmed cell death). These signals can be released into the extracellular space, where they bind to specific receptors on the target cell's surface, triggering intracellular signaling cascades that ultimately lead to a response.

Peptides are short chains of amino acids, while proteins are larger molecules made up of one or more polypeptide chains. Both can function as intercellular signaling molecules by acting as ligands for cell surface receptors or by being cleaved from larger precursor proteins and released into the extracellular space. Examples of intercellular signaling peptides and proteins include growth factors, cytokines, chemokines, hormones, neurotransmitters, and their respective receptors.

These molecules contribute to maintaining homeostasis within an organism by coordinating cellular activities across tissues and organs. Dysregulation of intercellular signaling pathways has been implicated in various diseases, such as cancer, autoimmune disorders, and neurodegenerative conditions. Therefore, understanding the mechanisms underlying intercellular signaling is essential for developing targeted therapies to treat these disorders.

Wnt proteins are a family of secreted signaling molecules that play crucial roles in the regulation of fundamental biological processes, including cell proliferation, differentiation, migration, and survival. They were first discovered in 1982 through genetic studies in Drosophila melanogaster (fruit flies) and have since been found to be highly conserved across various species, from invertebrates to humans.

Wnt proteins exert their effects by binding to specific receptors on the target cell surface, leading to the activation of several intracellular signaling pathways:

1. Canonical Wnt/β-catenin pathway: In the absence of Wnt ligands, β-catenin is continuously degraded by a destruction complex consisting of Axin, APC (Adenomatous polyposis coli), and GSK3β (Glycogen synthase kinase 3 beta). When Wnt proteins bind to their receptors Frizzled and LRP5/6, the formation of a "signalosome" complex leads to the inhibition of the destruction complex, allowing β-catenin to accumulate in the cytoplasm and translocate into the nucleus. Here, it interacts with TCF/LEF (T-cell factor/lymphoid enhancer-binding factor) transcription factors to regulate the expression of target genes involved in cell proliferation, differentiation, and survival.
2. Non-canonical Wnt pathways: These include the Wnt/Ca^2+^ pathway and the planar cell polarity (PCP) pathway. In the Wnt/Ca^2+^ pathway, Wnt ligands bind to Frizzled receptors and activate heterotrimeric G proteins, leading to an increase in intracellular Ca^2+^ levels and activation of downstream targets such as protein kinase C (PKC) and calcium/calmodulin-dependent protein kinase II (CAMKII). These signaling events ultimately regulate cell movement, adhesion, and gene expression. In the PCP pathway, Wnt ligands bind to Frizzled receptors and coreceptor complexes containing Ror2 or Ryk, leading to activation of small GTPases such as RhoA and Rac1, which control cytoskeletal organization and cell polarity.

Dysregulation of Wnt signaling has been implicated in various human diseases, including cancer, developmental disorders, and degenerative conditions. In cancer, aberrant activation of the canonical Wnt/β-catenin pathway contributes to tumor initiation, progression, and metastasis by promoting cell proliferation, survival, and epithelial-mesenchymal transition (EMT). Inhibitors targeting different components of the Wnt signaling pathway are currently being developed as potential therapeutic strategies for cancer treatment.

In medical terms, the "head" is the uppermost part of the human body that contains the brain, skull, face, eyes, nose, mouth, and ears. It is connected to the rest of the body by the neck and is responsible for many vital functions such as sight, hearing, smell, taste, touch, and thought processing. The head also plays a crucial role in maintaining balance, speech, and eating.

In situ hybridization (ISH) is a molecular biology technique used to detect and localize specific nucleic acid sequences, such as DNA or RNA, within cells or tissues. This technique involves the use of a labeled probe that is complementary to the target nucleic acid sequence. The probe can be labeled with various types of markers, including radioisotopes, fluorescent dyes, or enzymes.

During the ISH procedure, the labeled probe is hybridized to the target nucleic acid sequence in situ, meaning that the hybridization occurs within the intact cells or tissues. After washing away unbound probe, the location of the labeled probe can be visualized using various methods depending on the type of label used.

In situ hybridization has a wide range of applications in both research and diagnostic settings, including the detection of gene expression patterns, identification of viral infections, and diagnosis of genetic disorders.

Ectoderm is the outermost of the three primary germ layers in a developing embryo, along with the endoderm and mesoderm. The ectoderm gives rise to the outer covering of the body, including the skin, hair, nails, glands, and the nervous system, which includes the brain, spinal cord, and peripheral nerves. It also forms the lining of the mouth, anus, nose, and ears. Essentially, the ectoderm is responsible for producing all the epidermal structures and the neural crest cells that contribute to various derivatives such as melanocytes, adrenal medulla, smooth muscle, and peripheral nervous system components.

"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.

Bone Morphogenetic Proteins (BMPs) are a group of growth factors that play crucial roles in the development, growth, and repair of bones and other tissues. They belong to the Transforming Growth Factor-β (TGF-β) superfamily and were first discovered when researchers found that certain proteins extracted from demineralized bone matrix had the ability to induce new bone formation.

BMPs stimulate the differentiation of mesenchymal stem cells into osteoblasts, which are the cells responsible for bone formation. They also promote the recruitment and proliferation of these cells, enhancing the overall process of bone regeneration. In addition to their role in bone biology, BMPs have been implicated in various other biological processes, including embryonic development, wound healing, and the regulation of fat metabolism.

There are several types of BMPs (BMP-2, BMP-4, BMP-7, etc.) that exhibit distinct functions and expression patterns. Due to their ability to stimulate bone formation, recombinant human BMPs have been used in clinical applications, such as spinal fusion surgery and non-healing fracture treatment. However, the use of BMPs in medicine has been associated with certain risks and complications, including uncontrolled bone growth, inflammation, and cancer development, which necessitates further research to optimize their therapeutic potential.

Tissue transplantation is a medical procedure where tissues from one part of the body or from another individual's body are removed and implanted in a recipient to replace damaged, diseased, or missing tissues. The tissues may include skin, bone, tendons, ligaments, heart valves, corneas, or even entire organs such as hearts, lungs, livers, and kidneys.

The donor tissue must be compatible with the recipient's body to reduce the risk of rejection, which is the immune system attacking and destroying the transplanted tissue. This often requires matching certain proteins called human leukocyte antigens (HLAs) found on the surface of most cells in the body.

Tissue transplantation can significantly improve a patient's quality of life or, in some cases, save their life. However, it does carry risks such as infection, bleeding, and rejection, which require careful monitoring and management.

The nervous system is a complex, highly organized network of specialized cells called neurons and glial cells that communicate with each other via electrical and chemical signals to coordinate various functions and activities in the body. It consists of two main parts: the central nervous system (CNS), including the brain and spinal cord, and the peripheral nervous system (PNS), which includes all the nerves and ganglia outside the CNS.

The primary function of the nervous system is to receive, process, and integrate information from both internal and external environments and then respond by generating appropriate motor outputs or behaviors. This involves sensing various stimuli through specialized receptors, transmitting this information through afferent neurons to the CNS for processing, integrating this information with other inputs and memories, making decisions based on this processed information, and finally executing responses through efferent neurons that control effector organs such as muscles and glands.

The nervous system can be further divided into subsystems based on their functions, including the somatic nervous system, which controls voluntary movements and reflexes; the autonomic nervous system, which regulates involuntary physiological processes like heart rate, digestion, and respiration; and the enteric nervous system, which is a specialized subset of the autonomic nervous system that controls gut functions. Overall, the nervous system plays a critical role in maintaining homeostasis, regulating behavior, and enabling cognition and consciousness.

LIM-homeodomain proteins are a family of transcription factors that contain both LIM domains and homeodomains. LIM domains are cysteine-rich motifs that function in protein-protein interactions, often mediating the formation of multimeric complexes. Homeodomains are DNA-binding domains that recognize and bind to specific DNA sequences, thereby regulating gene transcription.

LIM-homeodomain proteins play important roles in various developmental processes, including cell fate determination, differentiation, and migration. They have been implicated in the regulation of muscle, nerve, and cardiovascular development, as well as in cancer and other diseases. Some examples of LIM-homeodomain proteins include LMX1A, LHX2, and ISL1.

These proteins are characterized by the presence of two LIM domains at the N-terminus and a homeodomain at the C-terminus. The LIM domains are involved in protein-protein interactions, while the homeodomain is responsible for DNA binding and transcriptional regulation. Some LIM-homeodomain proteins also contain other functional domains, such as zinc fingers or leucine zippers, which contribute to their diverse functions.

Overall, LIM-homeodomain proteins are important regulators of gene expression and play critical roles in various developmental and disease processes.

Morphogenesis is a term used in developmental biology and refers to the process by which cells give rise to tissues and organs with specific shapes, structures, and patterns during embryonic development. This process involves complex interactions between genes, cells, and the extracellular environment that result in the coordinated movement and differentiation of cells into specialized functional units.

Morphogenesis is a dynamic and highly regulated process that involves several mechanisms, including cell proliferation, death, migration, adhesion, and differentiation. These processes are controlled by genetic programs and signaling pathways that respond to environmental cues and regulate the behavior of individual cells within a developing tissue or organ.

The study of morphogenesis is important for understanding how complex biological structures form during development and how these processes can go awry in disease states such as cancer, birth defects, and degenerative disorders.

I'm sorry for any confusion, but "Silver" is not a medical term. It is a chemical element with the symbol Ag and atomic number 47. Silver is a soft, white, lustrous transition metal that occurs in its pure, free form (native silver) as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite.

In the medical field, silver compounds have been used for their antimicrobial properties. For example, silver sulfadiazine is a common topical cream used to prevent or treat wound infections. Colloidal silver, a suspension of silver particles in a liquid, has also been promoted as a dietary supplement and alternative treatment for various conditions, but its effectiveness and safety are not well-established.

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.

Homeobox genes are a specific class of genes that play a crucial role in the development and regulation of an organism's body plan. They encode transcription factors, which are proteins that regulate the expression of other genes. The homeobox region within these genes contains a highly conserved sequence of about 180 base pairs that encodes a DNA-binding domain called the homeodomain. This domain is responsible for recognizing and binding to specific DNA sequences, thereby controlling the transcription of target genes.

Homeobox genes are particularly important during embryonic development, where they help establish the anterior-posterior axis and regulate the development of various organs and body segments. They also play a role in maintaining adult tissue homeostasis and have been implicated in certain diseases, including cancer. Mutations in homeobox genes can lead to developmental abnormalities and congenital disorders.

Some examples of homeobox gene families include HOX genes, PAX genes, and NKX genes, among others. These genes are highly conserved across species, indicating their fundamental role in the development and regulation of body plans throughout the animal kingdom.

Wnt1 protein is a member of the Wnt family, which is a group of secreted signaling proteins that play crucial roles in embryonic development and tissue homeostasis in adults. Specifically, Wnt1 is a highly conserved gene that encodes a glycoprotein with a molecular weight of approximately 40 kDa. It is primarily expressed in the developing nervous system, where it functions as a key regulator of neural crest cell migration and differentiation during embryogenesis.

Wnt1 protein mediates its effects by binding to Frizzled receptors on the surface of target cells, leading to the activation of several intracellular signaling pathways, including the canonical Wnt/β-catenin pathway and non-canonical Wnt/planar cell polarity (PCP) pathway. In the canonical pathway, Wnt1 protein stabilizes β-catenin, which then translocates to the nucleus and interacts with TCF/LEF transcription factors to regulate gene expression.

Dysregulation of Wnt1 signaling has been implicated in several human diseases, including cancer. For example, aberrant activation of the Wnt/β-catenin pathway by Wnt1 protein has been observed in various types of tumors, such as medulloblastomas and breast cancers, leading to uncontrolled cell proliferation and tumor growth. Therefore, understanding the molecular mechanisms underlying Wnt1 signaling is essential for developing novel therapeutic strategies for treating these diseases.

Activins are a type of protein that belongs to the transforming growth factor-beta (TGF-β) superfamily. They are produced and released by various cells in the body, including those in the ovaries, testes, pituitary gland, and other tissues. Activins play important roles in regulating several biological processes, such as cell growth, differentiation, and apoptosis (programmed cell death).

Activins bind to specific receptors on the surface of cells, leading to the activation of intracellular signaling pathways that control gene expression. They are particularly well-known for their role in reproductive biology, where they help regulate follicle stimulation and hormone production in the ovaries and testes. Activins also have been implicated in various disease processes, including cancer, fibrosis, and inflammation.

There are three main isoforms of activin in humans: activin A, activin B, and inhibin A. While activins and inhibins share similar structures and functions, they have opposite effects on the activity of the pituitary gland. Activins stimulate the production of follicle-stimulating hormone (FSH), while inhibins suppress it. This delicate balance between activins and inhibins helps regulate reproductive function and other physiological processes in the body.

"Left-right determination factors" refer to the genetic and molecular mechanisms that establish the left-right asymmetry during embryonic development. These factors determine which side of the body will become the left and which will become the right. The process is critical for the proper development and function of various organs, including the heart, lungs, and gut.

In humans, the primary left-right determination factor is a gene called NODAL, which is expressed on the left side of the embryo and initiates a cascade of molecular events that lead to the establishment of left-right asymmetry. Other genes, such as PITX2 and LEFTY2, are also involved in this process and help to amplify and maintain the left-right asymmetry.

Defects in left-right determination factors can result in a variety of congenital abnormalities, including heterotaxy syndrome, in which the organs are arranged in mirror-image patterns or randomly on both sides of the body.

Transcription factors are proteins that play a crucial role in regulating gene expression by controlling the transcription of DNA to messenger RNA (mRNA). They function by binding to specific DNA sequences, known as response elements, located in the promoter region or enhancer regions of target genes. This binding can either activate or repress the initiation of transcription, depending on the properties and interactions of the particular transcription factor. Transcription factors often act as part of a complex network of regulatory proteins that determine the precise spatiotemporal patterns of gene expression during development, differentiation, and homeostasis in an organism.

Endoderm is the innermost of the three primary germ layers in a developing embryo, along with the ectoderm and mesoderm. The endoderm gives rise to several internal tissues and organs, most notably those found in the digestive system and respiratory system. Specifically, it forms the lining of the gut tube, which eventually becomes the epithelial lining of the gastrointestinal tract, liver, pancreas, lungs, and other associated structures.

During embryonic development, the endoderm arises from the inner cell mass of the blastocyst, following a series of cell divisions and migrations that help to establish the basic body plan of the organism. As the embryo grows and develops, the endoderm continues to differentiate into more specialized tissues and structures, playing a critical role in the formation of many essential bodily functions.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

The metencephalon is a term used in the field of neuroanatomy, which refers to the portion of the brain that develops from the anterior rhombencephalic vesicle during embryonic development. It gives rise to two major structures in the adult brain: the pons and the cerebellum.

The pons is a region located in the brainstem that plays important roles in relaying sensory information, regulating respiration, and controlling facial movements. The cerebellum, on the other hand, is a structure located at the back of the brain that is responsible for coordinating muscle movements, maintaining balance, and contributing to cognitive functions such as attention and language processing.

Overall, the metencephalon is an essential part of the brain that plays critical roles in sensory perception, motor control, and various other physiological processes.

A blastula is a stage in the early development of many animals, including mammals. It is a hollow ball of cells that forms as a result of cleavage, which is the process of cell division during embryonic development. The blastula is typically characterized by the presence of a fluid-filled cavity called the blastocoel, which is surrounded by a single layer of cells known as the blastoderm.

In mammals, the blastula stage follows the morula stage, which is a solid mass of cells that results from cleavage of the fertilized egg. During further cell division and rearrangement, the cells in the morula become organized into an inner cell mass and an outer layer of cells, called the trophoblast. The inner cell mass will eventually give rise to the embryo proper, while the trophoblast will contribute to the formation of the placenta.

As the morula continues to divide and expand, it forms a cavity within the inner cell mass, which becomes the blastocoel. The single layer of cells surrounding the blastocoel is called the blastoderm. At this stage, the blastula is capable of further development through a process called gastrulation, during which the three germ layers of the embryo (ectoderm, mesoderm, and endoderm) are formed.

It's important to note that not all animals go through a blastula stage in their development. Some animals, such as insects and nematodes, have different patterns of early development that do not include a blastula stage.

Fetal proteins are a type of proteins that are produced by the fetus during pregnancy and can be detected in various biological samples, such as amniotic fluid or maternal blood. These proteins can provide valuable information about the health and development of the fetus. One commonly studied fetal protein is human chorionic gonadotropin (hCG), which is produced by the placenta and can be used as a marker for pregnancy and to detect potential complications, such as Down syndrome or spinal cord defects. Other examples of fetal proteins include alpha-fetoprotein (AFP) and human placental lactogen (hPL).

T-box domain proteins are a family of transcription factors that share a highly conserved DNA-binding domain, known as the T-box. The T-box domain is a DNA-binding motif that specifically recognizes and binds to T-box binding elements (TBEs) in the regulatory regions of target genes. These proteins play crucial roles during embryonic development, particularly in the formation of specific tissues and organs, such as the heart, limbs, and brain. Mutations in T-box domain proteins can lead to various congenital defects and developmental disorders. Some examples of T-box domain proteins include TBX1, TBX5, and TBX20.

Glycoproteins are complex proteins that contain oligosaccharide chains (glycans) covalently attached to their polypeptide backbone. These glycans are linked to the protein through asparagine residues (N-linked) or serine/threonine residues (O-linked). Glycoproteins play crucial roles in various biological processes, including cell recognition, cell-cell interactions, cell adhesion, and signal transduction. They are widely distributed in nature and can be found on the outer surface of cell membranes, in extracellular fluids, and as components of the extracellular matrix. The structure and composition of glycoproteins can vary significantly depending on their function and location within an organism.

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.

Conjoined twins, also known as Siamese twins, are a rare type of monozygotic (identical) twins who are born physically connected to each other. They develop from a single fertilized egg that fails to fully separate, resulting in various degrees of fusion between their bodies. The point of connection and the extent of sharing body parts can vary greatly between sets of conjoined twins. Some may be connected at the chest, abdomen, or hips, while others may share vital organs such as the heart or brain. Treatment options depend on the type of conjunction and whether separation is possible without causing harm to either twin. Conjoined twins occur in about 1 in every 200,000 live births.

Fibroblast Growth Factors (FGFs) are a family of growth factors that play crucial roles in various biological processes, including cell survival, proliferation, migration, and differentiation. They bind to specific tyrosine kinase receptors (FGFRs) on the cell surface, leading to intracellular signaling cascades that regulate gene expression and downstream cellular responses. FGFs are involved in embryonic development, tissue repair, and angiogenesis (the formation of new blood vessels). There are at least 22 distinct FGFs identified in humans, each with unique functions and patterns of expression. Some FGFs, like FGF1 and FGF2, have mitogenic effects on fibroblasts and other cell types, while others, such as FGF7 and FGF10, are essential for epithelial-mesenchymal interactions during organ development. Dysregulation of FGF signaling has been implicated in various pathological conditions, including cancer, fibrosis, and developmental disorders.

The blastoderm is the layer of cells that forms on the surface of a developing embryo, during the blastula stage of embryonic development. In mammals, this layer of cells is also known as the epiblast. The blastoderm is responsible for giving rise to all of the tissues and organs of the developing organism. It is formed by the cleavage of the fertilized egg, or zygote, and is typically a single layer of cells that surrounds a fluid-filled cavity called the blastocoel. The blastoderm plays a critical role in the early stages of embryonic development, and any disruptions to its formation or function can lead to developmental abnormalities or death of the embryo.

Matrix Attachment Regions (MARs) are specific DNA sequences that serve as anchor points for the attachment of chromosomes to the nuclear matrix, a network of fibers within the nucleus of a eukaryotic cell. MAR Binding Proteins (MARBPs) are a class of proteins that selectively bind to these MARs and play crucial roles in various nuclear processes such as DNA replication, transcription, repair, and chromosome organization.

MARBPs can be categorized into two main groups: structural and functional. Structural MARBPs help tether chromatin to the nuclear matrix and maintain the higher-order structure of chromatin. Functional MARBPs are involved in regulating gene expression, DNA replication, and repair by interacting with various transcription factors, enzymes, and other proteins at the MARs.

Examples of MARBPs include SATB1 (Special AT-rich sequence-binding protein 1), CTCF (CCCTC-binding factor), and NuMA (Nuclear Mitotic Apparatus protein). These proteins have been shown to play essential roles in chromatin organization, gene regulation, and cellular processes such as differentiation and development.

In summary, Matrix Attachment Region Binding Proteins are a class of nuclear proteins that selectively bind to specific DNA sequences called Matrix Attachment Regions (MARs). They contribute to various nuclear processes, including chromatin organization, gene regulation, DNA replication, and repair.

Bone Morphogenetic Protein 4 (BMP-4) is a growth factor that belongs to the transforming growth factor-beta (TGF-β) superfamily. It plays crucial roles in various biological processes, including embryonic development, cell growth, and differentiation. In the skeletal system, BMP-4 stimulates the formation of bone and cartilage by inducing the differentiation of mesenchymal stem cells into chondrocytes and osteoblasts. It also regulates the maintenance and repair of bones throughout life. An imbalance in BMP-4 signaling has been associated with several skeletal disorders, such as heterotopic ossification and osteoarthritis.

A chick embryo refers to the developing organism that arises from a fertilized chicken egg. It is often used as a model system in biological research, particularly during the stages of development when many of its organs and systems are forming and can be easily observed and manipulated. The study of chick embryos has contributed significantly to our understanding of various aspects of developmental biology, including gastrulation, neurulation, organogenesis, and pattern formation. Researchers may use various techniques to observe and manipulate the chick embryo, such as surgical alterations, cell labeling, and exposure to drugs or other agents.

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.

Silver nitrate is defined as an inorganic compound with the chemical formula AgNO3. It is a white or colorless crystalline solid that is highly soluble in water. Silver nitrate is commonly used in medicine as a topical antiseptic and caustic, particularly for the treatment of wounds, ulcers, and warts. When applied to skin or mucous membranes, it can help to destroy bacteria, viruses, and fungi, and promote healing. However, it can also cause irritation and tissue damage if used inappropriately, so it should be used with caution and under the guidance of a healthcare professional.

Beta-catenin is a protein that plays a crucial role in gene transcription and cell-cell adhesion. It is a key component of the Wnt signaling pathway, which regulates various processes such as cell proliferation, differentiation, and migration during embryonic development and tissue homeostasis in adults.

In the absence of Wnt signals, beta-catenin forms a complex with other proteins, including adenomatous polyposis coli (APC) and axin, which targets it for degradation by the proteasome. When Wnt ligands bind to their receptors, this complex is disrupted, allowing beta-catenin to accumulate in the cytoplasm and translocate to the nucleus. In the nucleus, beta-catenin interacts with T cell factor/lymphoid enhancer-binding factor (TCF/LEF) transcription factors to activate the transcription of target genes involved in cell fate determination, survival, and proliferation.

Mutations in the genes encoding components of the Wnt signaling pathway, including beta-catenin, have been implicated in various human diseases, such as cancer, developmental disorders, and degenerative conditions.

Hepatocyte Nuclear Factor 3-beta (HNF-3β, also known as FOXA3) is a transcription factor that plays crucial roles in the development and function of various organs, including the liver, pancreas, and kidneys. It belongs to the forkhead box (FOX) family of proteins, which are characterized by a conserved DNA-binding domain known as the forkhead box or winged helix domain.

In the liver, HNF-3β is essential for the differentiation and maintenance of hepatocytes, the primary functional cells of the liver. It regulates the expression of several genes involved in liver-specific functions such as glucose metabolism, bile acid synthesis, and detoxification.

HNF-3β also has important roles in the pancreas, where it helps regulate the development and function of insulin-producing beta cells. In the kidneys, HNF-3β is involved in the differentiation and maintenance of the nephron, the functional unit responsible for filtering blood and maintaining water and electrolyte balance.

Mutations in the gene encoding HNF-3β have been associated with several genetic disorders, including maturity-onset diabetes of the young (MODY) and renal cysts and diabetes syndrome (RCAD).

Amphibians are a class of cold-blooded vertebrates that include frogs, toads, salamanders, newts, and caecilians. They are characterized by their four-limbed body structure, moist skin, and double circulation system with three-chambered hearts. Amphibians are unique because they have a life cycle that involves two distinct stages: an aquatic larval stage (usually as a tadpole or larva) and a terrestrial adult stage. They typically start their lives in water, undergoing metamorphosis to develop lungs and legs for a land-dwelling existence. Many amphibians are also known for their complex reproductive behaviors and vocalizations.

Transforming Growth Factor-beta (TGF-β) is a type of cytokine, which is a cell signaling protein involved in the regulation of various cellular processes, including cell growth, differentiation, and apoptosis (programmed cell death). TGF-β plays a critical role in embryonic development, tissue homeostasis, and wound healing. It also has been implicated in several pathological conditions such as fibrosis, cancer, and autoimmune diseases.

TGF-β exists in multiple isoforms (TGF-β1, TGF-β2, and TGF-β3) that are produced by many different cell types, including immune cells, epithelial cells, and fibroblasts. The protein is synthesized as a precursor molecule, which is cleaved to release the active TGF-β peptide. Once activated, TGF-β binds to its receptors on the cell surface, leading to the activation of intracellular signaling pathways that regulate gene expression and cell behavior.

In summary, Transforming Growth Factor-beta (TGF-β) is a multifunctional cytokine involved in various cellular processes, including cell growth, differentiation, apoptosis, embryonic development, tissue homeostasis, and wound healing. It has been implicated in several pathological conditions such as fibrosis, cancer, and autoimmune diseases.

Repressor proteins are a type of regulatory protein in molecular biology that suppress the transcription of specific genes into messenger RNA (mRNA) by binding to DNA. They function as part of gene regulation processes, often working in conjunction with an operator region and a promoter region within the DNA molecule. Repressor proteins can be activated or deactivated by various signals, allowing for precise control over gene expression in response to changing cellular conditions.

There are two main types of repressor proteins:

1. DNA-binding repressors: These directly bind to specific DNA sequences (operator regions) near the target gene and prevent RNA polymerase from transcribing the gene into mRNA.
2. Allosteric repressors: These bind to effector molecules, which then cause a conformational change in the repressor protein, enabling it to bind to DNA and inhibit transcription.

Repressor proteins play crucial roles in various biological processes, such as development, metabolism, and stress response, by controlling gene expression patterns in cells.

Inhibins are a group of protein hormones that play a crucial role in regulating the function of the reproductive system, specifically by inhibiting the production of follicle-stimulating hormone (FSH) in the pituitary gland. They are produced and secreted primarily by the granulosa cells in the ovaries of females and Sertoli cells in the testes of males.

Inhibins consist of two subunits, an alpha subunit, and a beta subunit, which can be further divided into two types: inhibin A and inhibin B. Inhibin A is primarily produced by the granulosa cells of developing follicles in the ovary, while inhibin B is mainly produced by the Sertoli cells in the testes.

By regulating FSH production, inhibins help control the development and maturation of ovarian follicles in females and spermatogenesis in males. Abnormal levels of inhibins have been associated with various reproductive disorders, including polycystic ovary syndrome (PCOS) and certain types of cancer.

The "tectum mesencephali" is a term used in anatomy to refer to the roof or dorsal portion of the midbrain, which is a part of the brainstem. It plays a crucial role in visual and auditory processing, as well as motor coordination. The tectum mesencephali contains several important structures, including the superior colliculi and the inferior colliculi, which are involved in the reflexive responses to visual and auditory stimuli, respectively. Additionally, the tectum mesencephali is connected to various other regions of the brain, allowing for the integration of sensory information and the coordination of motor responses.

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.

The neural plate is a structure formed during the embryonic development of vertebrates. It is a thickened plate of ectodermal cells located on the dorsal surface of the developing embryo. The neural plate gives rise to the central nervous system, including the brain and spinal cord.

The process of neural plate formation begins with the specification of ectodermal cells into neural fated cells, a process that is regulated by various signaling molecules. Once specified, these cells undergo morphological changes, resulting in the thickening of the ectoderm to form the neural plate.

The neural plate then undergoes a series of folding movements, leading to the formation of the neural tube, which eventually develops into the brain and spinal cord. The edges of the neural plate, known as the neural folds, come together and fuse, forming a closed tube. Failure of the neural folds to fuse properly can result in neural tube defects, such as spina bifida.

Overall, the neural plate is a critical structure in the development of the nervous system in vertebrates, and its formation and subsequent development are tightly regulated by various genetic and environmental factors.

Trans-activators are proteins that increase the transcriptional activity of a gene or a set of genes. They do this by binding to specific DNA sequences and interacting with the transcription machinery, thereby enhancing the recruitment and assembly of the complexes needed for transcription. In some cases, trans-activators can also modulate the chromatin structure to make the template more accessible to the transcription machinery.

In the context of HIV (Human Immunodeficiency Virus) infection, the term "trans-activator" is often used specifically to refer to the Tat protein. The Tat protein is a viral regulatory protein that plays a critical role in the replication of HIV by activating the transcription of the viral genome. It does this by binding to a specific RNA structure called the Trans-Activation Response Element (TAR) located at the 5' end of all nascent HIV transcripts, and recruiting cellular cofactors that enhance the processivity and efficiency of RNA polymerase II, leading to increased viral gene expression.

Drug packaging refers to the process and materials used to enclose, protect, and provide information about a pharmaceutical product. The package may include the container for the medication, such as a bottle or blister pack, as well as any accompanying leaflets or inserts that contain details about the drug's dosage, side effects, and proper use.

The packaging of drugs serves several important functions:

1. Protection: Proper packaging helps to protect the medication from physical damage, contamination, and degradation due to exposure to light, moisture, or air.
2. Child-resistance: Many drug packages are designed to be child-resistant, meaning they are difficult for young children to open but can still be easily accessed by adults.
3. Tamper-evidence: Packaging may also include features that make it easy to detect if the package has been tampered with or opened without authorization.
4. Labeling: Drug packaging must comply with regulatory requirements for labeling, including providing clear and accurate information about the drug's ingredients, dosage, warnings, and precautions.
5. Unit-dose packaging: Some drugs are packaged in unit-dose form, which means that each dose is individually wrapped or sealed in a separate package. This can help to reduce medication errors and ensure that patients receive the correct dosage.
6. Branding and marketing: Drug packaging may also serve as a tool for branding and marketing the product, with distinctive colors, shapes, and graphics that help to differentiate it from similar products.

Hedgehog proteins are a group of signaling molecules that play crucial roles in the development and regulation of various biological processes in animals. They are named after the hedgehog mutant fruit flies, which have spiky bristles due to defects in this pathway. These proteins are involved in cell growth, differentiation, and tissue regeneration. They exert their effects by binding to specific receptors on the surface of target cells, leading to a cascade of intracellular signaling events that ultimately influence gene expression and cell behavior.

There are three main types of Hedgehog proteins in mammals: Sonic hedgehog (Shh), Indian hedgehog (Ihh), and Desert hedgehog (Dhh). These protecules undergo post-translational modifications, including cleavage and lipid modification, which are essential for their activity. Dysregulation of Hedgehog signaling has been implicated in various diseases, including cancer, developmental abnormalities, and degenerative disorders.

The prosencephalon is a term used in the field of neuroembryology, which refers to the developmental stage of the forebrain in the embryonic nervous system. It is one of the three primary vesicles that form during the initial stages of neurulation, along with the mesencephalon (midbrain) and rhombencephalon (hindbrain).

The prosencephalon further differentiates into two secondary vesicles: the telencephalon and diencephalon. The telencephalon gives rise to structures such as the cerebral cortex, basal ganglia, and olfactory bulbs, while the diencephalon develops into structures like the thalamus, hypothalamus, and epithalamus.

It is important to note that 'prosencephalon' itself is not used as a medical term in adult neuroanatomy, but it is crucial for understanding the development of the human brain during embryogenesis.

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.

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.

'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.

Blastomeres are early stage embryonic cells that result from the initial rounds of cell division in a fertilized egg, also known as a zygote. These cells are typically smaller and have a more simple organization compared to more mature cells. They are important for the normal development of the embryo and contribute to the formation of the blastocyst, which is an early stage embryonic structure that will eventually give rise to the fetus. The process of cell division that produces blastomeres is called cleavage.

Nerve tissue proteins are specialized proteins found in the nervous system that provide structural and functional support to nerve cells, also known as neurons. These proteins include:

1. Neurofilaments: These are type IV intermediate filaments that provide structural support to neurons and help maintain their shape and size. They are composed of three subunits - NFL (light), NFM (medium), and NFH (heavy).

2. Neuronal Cytoskeletal Proteins: These include tubulins, actins, and spectrins that provide structural support to the neuronal cytoskeleton and help maintain its integrity.

3. Neurotransmitter Receptors: These are specialized proteins located on the postsynaptic membrane of neurons that bind neurotransmitters released by presynaptic neurons, triggering a response in the target cell.

4. Ion Channels: These are transmembrane proteins that regulate the flow of ions across the neuronal membrane and play a crucial role in generating and transmitting electrical signals in neurons.

5. Signaling Proteins: These include enzymes, receptors, and adaptor proteins that mediate intracellular signaling pathways involved in neuronal development, differentiation, survival, and death.

6. Adhesion Proteins: These are cell surface proteins that mediate cell-cell and cell-matrix interactions, playing a crucial role in the formation and maintenance of neural circuits.

7. Extracellular Matrix Proteins: These include proteoglycans, laminins, and collagens that provide structural support to nerve tissue and regulate neuronal migration, differentiation, and survival.

The Central Nervous System (CNS) is the part of the nervous system that consists of the brain and spinal cord. It is called the "central" system because it receives information from, and sends information to, the rest of the body through peripheral nerves, which make up the Peripheral Nervous System (PNS).

The CNS is responsible for processing sensory information, controlling motor functions, and regulating various autonomic processes like heart rate, respiration, and digestion. The brain, as the command center of the CNS, interprets sensory stimuli, formulates thoughts, and initiates actions. The spinal cord serves as a conduit for nerve impulses traveling to and from the brain and the rest of the body.

The CNS is protected by several structures, including the skull (which houses the brain) and the vertebral column (which surrounds and protects the spinal cord). Despite these protective measures, the CNS remains vulnerable to injury and disease, which can have severe consequences due to its crucial role in controlling essential bodily functions.

A group of chordate animals (Phylum Chordata) that have a vertebral column, or backbone, made up of individual vertebrae. This group includes mammals, birds, reptiles, amphibians, and fish. Vertebrates are characterized by the presence of a notochord, which is a flexible, rod-like structure that runs along the length of the body during development; a dorsal hollow nerve cord; and pharyngeal gill slits at some stage in their development. The vertebral column provides support and protection for the spinal cord and allows for the development of complex movements and behaviors.

Chordata is a phylum in the animal kingdom that contains animals with notochords, dorsal hollow nerve cords, pharyngeal gill slits, and post-anal tails at some point during their development. This phylum includes organisms that are bilaterally symmetrical, have a coelom (a body cavity), and are triploblastic (having three germ layers: ectoderm, mesoderm, and endoderm).

The Chordata phylum is divided into three subphyla: Urochordata (tunicates or sea squirts), Cephalochordata (lancelets or amphioxi), and Vertebrata (animals with backbones, including fish, amphibians, reptiles, birds, and mammals). The presence of the notochord, a flexible, rod-like structure that runs along the length of the body, is a key characteristic that unites these diverse groups.

In vertebrates, the notochord is replaced during development by the spinal column or backbone, which provides support and protection for the central nervous system. The dorsal hollow nerve cord develops into the brain and spinal cord in vertebrates, while pharyngeal gill slits are modified into various structures such as the tonsils, thymus, and middle ear bones in different vertebrate groups.

Overall, Chordata represents a diverse group of organisms with shared developmental features that have evolved to adapt to various ecological niches throughout history.

Follistatin is a glycoprotein that is naturally produced in various tissues, including the ovaries, pituitary gland, and skeletal muscle. It plays an essential role in regulating the activity of members of the transforming growth factor-β (TGF-β) superfamily, particularly the bone morphogenetic proteins (BMPs) and activins.

Follistatin binds to these signaling molecules with high affinity, preventing them from interacting with their receptors and thereby inhibiting their downstream signaling pathways. By doing so, follistatin helps regulate processes such as follicle stimulation in the ovaries, neurogenesis, muscle growth, and inflammation.

Increased levels of follistatin have been associated with muscle hypertrophy, while its deficiency can lead to impaired fertility and developmental abnormalities.

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.

In the context of human anatomy, the term "tail" is not used to describe any part of the body. Humans are considered tailless primates, and there is no structure or feature that corresponds directly to the tails found in many other animals.

However, there are some medical terms related to the lower end of the spine that might be confused with a tail:

1. Coccyx (Tailbone): The coccyx is a small triangular bone at the very bottom of the spinal column, formed by the fusion of several rudimentary vertebrae. It's also known as the tailbone because it resembles the end of an animal's tail in its location and appearance.
2. Cauda Equina (Horse's Tail): The cauda equina is a bundle of nerve roots at the lower end of the spinal cord, just above the coccyx. It got its name because it looks like a horse's tail due to the numerous rootlets radiating from the conus medullaris (the tapering end of the spinal cord).

These two structures are not tails in the traditional sense but rather medical terms related to the lower end of the human spine.

Ribosomal DNA (rDNA) refers to the specific regions of DNA in a cell that contain the genes for ribosomal RNA (rRNA). Ribosomes are complex structures composed of proteins and rRNA, which play a crucial role in protein synthesis by translating messenger RNA (mRNA) into proteins.

In humans, there are four types of rRNA molecules: 18S, 5.8S, 28S, and 5S. These rRNAs are encoded by multiple copies of rDNA genes that are organized in clusters on specific chromosomes. In humans, the majority of rDNA genes are located on the short arms of acrocentric chromosomes 13, 14, 15, 21, and 22.

Each cluster of rDNA genes contains both transcribed and non-transcribed spacer regions. The transcribed regions contain the genes for the four types of rRNA, while the non-transcribed spacers contain regulatory elements that control the transcription of the rRNA genes.

The number of rDNA copies varies between species and even within individuals of the same species. The copy number can also change during development and in response to environmental factors. Variations in rDNA copy number have been associated with various diseases, including cancer and neurological disorders.

Developmental genes are a set of genes that play crucial roles during the development of an organism, from fertilization to adult form. These genes are responsible for controlling fundamental processes such as cell growth, differentiation, and programmed cell death (apoptosis), which ultimately lead to the formation of various tissues, organs, and body structures. They often encode transcription factors and signaling molecules that regulate complex gene networks and cascades. Some well-known developmental genes are involved in pattern formation, segmentation, and morphogenesis, ensuring the proper spatial organization and function of different parts of the organism. Examples include Hox genes, Wnt genes, and TGF-β genes. Mutations in developmental genes can result in various developmental disorders and congenital abnormalities.

Chordata is a phylum in the animal kingdom that includes animals with a notochord, dorsal hollow nerve cord, pharyngeal gill slits, and a post-anal tail at some point during their development. Nonvertebrate Chordates include two classes: Tunicata (sea squirts and salps) and Cephalochordata (lancelets). These animals do not have a backbone or vertebral column, which is why they are considered nonvertebrate. Despite the lack of a vertebral column, these animals share other common characteristics with Vertebrates, such as a circulatory system and a complex nervous system.

Cytoskeletal proteins are a type of structural proteins that form the cytoskeleton, which is the internal framework of cells. The cytoskeleton provides shape, support, and structure to the cell, and plays important roles in cell division, intracellular transport, and maintenance of cell shape and integrity.

There are three main types of cytoskeletal proteins: actin filaments, intermediate filaments, and microtubules. Actin filaments are thin, rod-like structures that are involved in muscle contraction, cell motility, and cell division. Intermediate filaments are thicker than actin filaments and provide structural support to the cell. Microtubules are hollow tubes that are involved in intracellular transport, cell division, and maintenance of cell shape.

Cytoskeletal proteins are composed of different subunits that polymerize to form filamentous structures. These proteins can be dynamically assembled and disassembled, allowing cells to change their shape and move. Mutations in cytoskeletal proteins have been linked to various human diseases, including cancer, neurological disorders, and muscular dystrophies.

High Mobility Group Box (HMGB) proteins are a family of nuclear proteins that are highly conserved and expressed in eukaryotic cells. They play a crucial role in the regulation of gene expression, DNA repair, and maintenance of nucleosome structure. HMGB proteins contain two positively charged DNA-binding domains (HMG boxes) and a negatively charged acidic tail. These proteins can bind to DNA in a variety of ways, bending it and altering its structure, which in turn affects the binding of other proteins and the transcriptional activity of genes. HMGB proteins can also be released from cells under conditions of stress or injury, where they act as damage-associated molecular patterns (DAMPs) and contribute to the inflammatory response.

Embryonic development is the series of growth and developmental stages that occur during the formation and early growth of the embryo. In humans, this stage begins at fertilization (when the sperm and egg cell combine) and continues until the end of the 8th week of pregnancy. During this time, the fertilized egg (now called a zygote) divides and forms a blastocyst, which then implants into the uterus. The cells in the blastocyst begin to differentiate and form the three germ layers: the ectoderm, mesoderm, and endoderm. These germ layers will eventually give rise to all of the different tissues and organs in the body.

Embryonic development is a complex and highly regulated process that involves the coordinated interaction of genetic and environmental factors. It is characterized by rapid cell division, migration, and differentiation, as well as programmed cell death (apoptosis) and tissue remodeling. Abnormalities in embryonic development can lead to birth defects or other developmental disorders.

It's important to note that the term "embryo" is used to describe the developing organism from fertilization until the end of the 8th week of pregnancy in humans, after which it is called a fetus.

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.

Ribosomal RNA (rRNA) is a type of RNA molecule that is a key component of ribosomes, which are the cellular structures where protein synthesis occurs in cells. In ribosomes, rRNA plays a crucial role in the process of translation, where genetic information from messenger RNA (mRNA) is translated into proteins.

Ribosomal RNA is synthesized in the nucleus and then transported to the cytoplasm, where it assembles with ribosomal proteins to form ribosomes. Within the ribosome, rRNA provides a structural framework for the assembly of the ribosome and also plays an active role in catalyzing the formation of peptide bonds between amino acids during protein synthesis.

There are several different types of rRNA molecules, including 5S, 5.8S, 18S, and 28S rRNA, which vary in size and function. These rRNA molecules are highly conserved across different species, indicating their essential role in protein synthesis and cellular function.

A blastocyst is a stage in the early development of a fertilized egg, or embryo, in mammals. It occurs about 5-6 days after fertilization and consists of an outer layer of cells called trophoblasts, which will eventually form the placenta, and an inner cell mass, which will give rise to the fetus. The blastocyst is characterized by a fluid-filled cavity called the blastocoel. This stage is critical for the implantation of the embryo into the uterine lining.

In medical terms, "wing" is not a term that is used as a standalone definition. However, it can be found in the context of certain anatomical structures or medical conditions. For instance, the "wings" of the lungs refer to the upper and lower portions of the lungs that extend from the main body of the organ. Similarly, in dermatology, "winging" is used to describe the spreading out or flaring of the wings of the nose, which can be a characteristic feature of certain skin conditions like lupus.

It's important to note that medical terminology can be highly specific and context-dependent, so it's always best to consult with a healthcare professional for accurate information related to medical definitions or diagnoses.

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.

Bone morphogenetic protein (BMP) receptors are a type of cell surface receptor that play a crucial role in bone and cartilage development, as well as in other biological processes such as wound healing and embryonic development. These receptors are part of the TGF-β (transforming growth factor-beta) superfamily and are composed of two types of subunits: type I and type II.

Type I BMP receptors include BMPR1A, BMPR1B, and ACTRIIA/B. Type II BMP receptors include BMPR2, ACVR2A, and ACVR2B. When BMPs bind to these receptors, they initiate a signaling cascade that leads to the activation of downstream targets involved in bone formation, cartilage development, and other processes.

Mutations in BMP receptor genes have been associated with various genetic disorders, including fibrodysplasia ossificans progressiva (FOP), a rare condition characterized by the abnormal formation of bone in muscles, tendons, and ligaments. Additionally, dysregulation of BMP signaling has been implicated in diseases such as cancer, where it can contribute to tumor growth and metastasis.

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.

'Cell lineage' is a term used in biology and medicine to describe the developmental history or relationship of a cell or group of cells to other cells, tracing back to the original progenitor or stem cell. It refers to the series of cell divisions and differentiation events that give rise to specific types of cells in an organism over time.

In simpler terms, cell lineage is like a family tree for cells, showing how they are related to each other through a chain of cell division and specialization events. This concept is important in understanding the development, growth, and maintenance of tissues and organs in living beings.

I believe there may be some confusion in your question. "Quail" is typically used to refer to a group of small birds that belong to the family Phasianidae and the subfamily Perdicinae. There is no established medical definition for "quail."

However, if you're referring to the verb "to quail," it means to shrink back, draw back, or cower, often due to fear or intimidation. In a medical context, this term could be used metaphorically to describe a patient's psychological response to a threatening situation, such as receiving a difficult diagnosis. But again, "quail" itself is not a medical term.

Cell differentiation is the process by which a less specialized cell, or stem cell, becomes a more specialized cell type with specific functions and structures. This process involves changes in gene expression, which are regulated by various intracellular signaling pathways and transcription factors. Differentiation results in the development of distinct cell types that make up tissues and organs in multicellular organisms. It is a crucial aspect of embryonic development, tissue repair, and maintenance of homeostasis in the body.

Somites are transient, segmentally repeated embryonic structures that form along the anterior-posterior body axis during vertebrate development. They are derived from the paraxial mesoderm and give rise to various tissues, including the sclerotome (which forms the vertebrae and ribs), myotome (which forms the skeletal muscles of the back and limbs), and dermatome (which forms the dermis of the skin).

Each somite is a block-like structure that is arranged in a repeating pattern along the notochord, which is a flexible rod-like structure that provides mechanical support to the developing embryo. The formation of somites is a critical step in the development of the vertebrate body plan, as they help to establish the segmental organization of the musculoskeletal system and contribute to the formation of other important structures such as the dermis and the circulatory system.

The process of somitogenesis, or the formation of somites, is a highly regulated and coordinated event that involves the interaction of various signaling molecules and genetic pathways. Defects in somite formation can lead to a range of developmental abnormalities, including spinal deformities, muscle weakness, and skin defects.

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.

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 Neural Tube is a structure that forms during the development of an embryo and eventually becomes the brain, spinal cord, and other parts of the nervous system. It is a narrow channel that runs along the back of the embryo, forming from the ectoderm (one of the three germ layers) and closing around the 23rd or 26th day after conception. Defects in the closure of the neural tube can lead to conditions such as spina bifida and anencephaly.

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.

The PAX2 transcription factor is a protein that plays a crucial role in the development and function of the kidneys and urinary system. It belongs to the PAX family of transcription factors, which are characterized by a highly conserved DNA-binding domain called the paired box. The PAX2 protein helps regulate gene expression during embryonic development, including genes involved in the formation of the nephrons, the functional units of the kidneys.

PAX2 is expressed in the intermediate mesoderm, which gives rise to the kidneys and other organs of the urinary system. It helps to specify the fate of these cells and promote their differentiation into mature kidney structures. In addition to its role in kidney development, PAX2 has also been implicated in the development of the eye, ear, and central nervous system.

Mutations in the PAX2 gene have been associated with various genetic disorders, including renal coloboma syndrome, which is characterized by kidney abnormalities and eye defects. Proper regulation of PAX2 expression is essential for normal development and function of the urinary system and other organs.

"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.

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.

'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.

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.

I'm sorry for any confusion, but "History, 20th Century" is a broad and complex topic that refers to the events, developments, and transformations that occurred throughout the world during the 1900s. It is not a medical term or concept. If you're interested in learning more about this historical period, I would recommend consulting a history textbook, reputable online resources, or speaking with a historian. They can provide detailed information about the political, social, economic, and cultural changes that took place during the 20th century.

Medication systems refer to the organizational and operational structures, processes, and technologies that are put in place to ensure the safe and effective use of medications in healthcare settings. These systems encompass all aspects of medication management, including prescribing, transcribing, dispensing, administering, and monitoring. They are designed to minimize errors, improve patient outcomes, and reduce costs associated with medication-related harm.

Medication systems may include various components such as:

1. Medication ordering and documentation systems that standardize the way medications are prescribed and documented in the medical record.
2. Computerized physician order entry (CPOE) systems that allow providers to enter medication orders electronically, reducing errors associated with handwritten orders.
3. Pharmacy information systems that manage medication inventory, track medication use, and ensure the accuracy of dispensed medications.
4. Medication administration records (MARs) that document the medications administered to each patient, including the dose, route, and time of administration.
5. Automated dispensing systems that allow medications to be dispensed directly to patients or medication carts, reducing errors associated with manual handling of medications.
6. Smart infusion pumps that incorporate safety features such as dose error reduction software and drug libraries to prevent medication errors during infusion therapy.
7. Medication reconciliation processes that ensure accurate and up-to-date medication lists are maintained for each patient, reducing the risk of medication errors during transitions of care.
8. Clinical decision support systems that provide alerts and reminders to providers regarding potential drug-drug interactions, dosing errors, and other medication-related risks.
9. Patient education materials that provide clear and concise information about medications, including dosage instructions, side effects, and storage requirements.
10. Performance improvement processes that monitor medication use and outcomes, identify areas for improvement, and implement changes to the medication system as needed.

Situs Inversus is a congenital condition in which the major visceral organs are situated in mirror-image positions to their normal locations. Instead of being on the left side, the heart and its large blood vessels are on the right side, while the liver is on the left side and the lungs are reversed. The stomach, spleen, and pancreas may also be affected. It's important to note that this condition is generally asymptomatic and often goes unnoticed unless there are complications or associated abnormalities.

There are two types of Situs Inversus: total (complete reversal of all organs) and partial (reversal of only some organs). Total Situs Inversus is also sometimes referred to as "mirror-image dextrocardia" because the heart, which is usually on the left side, is located on the right side in a mirrored position.

While Situs Inversus itself does not typically cause health problems, people with this condition may have an increased risk for certain medical conditions, such as congenital heart defects or primary ciliary dyskinesia (PCD), which can lead to chronic respiratory infections and infertility.

A zygote is the initial cell formed when a sperm fertilizes an egg, also known as an oocyte. This occurs in the process of human reproduction and marks the beginning of a new genetic identity, containing 46 chromosomes - 23 from the sperm and 23 from the egg. The zygote starts the journey of cell division and growth, eventually developing into a blastocyst, then an embryo, and finally a fetus over the course of pregnancy.

Fibroblast Growth Factor 3 (FGF3) is a protein that belongs to the fibroblast growth factor family, which plays crucial roles in various biological processes such as cell survival, proliferation, migration, and differentiation. Specifically, FGF3 is involved in embryonic development, tissue repair, and maintenance of homeostasis. It exerts its functions by binding to FGF receptors (FGFRs) and activating downstream signaling pathways. Mutations in the FGF3 gene have been associated with certain diseases, including craniosynostosis, a condition characterized by premature fusion of skull bones.

The Wnt signaling pathway is a complex cell communication system that plays a critical role in embryonic development, tissue regeneration, and cancer. It is named after the Wingless (Wg) gene in Drosophila melanogaster and the Int-1 gene in mice, both of which were found to be involved in this pathway.

In essence, the Wnt signaling pathway involves the binding of Wnt proteins to Frizzled receptors on the cell surface, leading to the activation of intracellular signaling cascades. There are three main branches of the Wnt signaling pathway: the canonical (or Wnt/β-catenin) pathway, the noncanonical planar cell polarity (PCP) pathway, and the noncanonical Wnt/calcium pathway.

The canonical Wnt/β-catenin pathway is the most well-studied branch. In the absence of Wnt signaling, cytoplasmic β-catenin is constantly phosphorylated by a destruction complex consisting of Axin, APC, GSK3β, and CK1, leading to its ubiquitination and degradation in the proteasome. When Wnt ligands bind to Frizzled receptors and their coreceptor LRP5/6, Dishevelled is recruited and inhibits the destruction complex, allowing β-catenin to accumulate in the cytoplasm and translocate into the nucleus. In the nucleus, β-catenin interacts with TCF/LEF transcription factors to regulate the expression of target genes involved in cell proliferation, differentiation, and survival.

Dysregulation of the Wnt signaling pathway has been implicated in various human diseases, including cancer, developmental disorders, and degenerative conditions. For example, mutations in components of the canonical Wnt/β-catenin pathway can lead to the accumulation of β-catenin and subsequent activation of oncogenic target genes, contributing to tumorigenesis in various types of cancer.

Hesperidin is a flavonoid, specifically a type of flavanone glycoside, that is commonly found in citrus fruits such as oranges, lemons, and grapefruits. It is particularly abundant in the peel and membranes of these fruits. Hesperidin has been studied for its potential health benefits, including its antioxidant, anti-inflammatory, and cardiovascular protective properties. However, more research is needed to fully understand its effects and potential therapeutic uses.

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.

Developmental biology is a branch of biological research that studies the processes by which organisms grow and develop from fertilized eggs (zygotes) to adults. This field of study encompasses understanding the genetic, epigenetic, environmental, and molecular mechanisms that guide the developmental trajectory of an organism, including cellular differentiation, pattern formation, morphogenesis, and growth control.

Developmental biology has important implications for understanding congenital disorders, regenerative medicine, and evolutionary biology. Researchers in this field use a variety of model organisms, such as fruit flies (Drosophila melanogaster), zebrafish (Danio rerio), mice (Mus musculus), and nematodes (Caenorhabditis elegans), to investigate the fundamental principles that govern developmental processes. These insights can then be applied to understanding human development and disease.

Proto-oncogene proteins are normal cellular proteins that play crucial roles in various cellular processes, such as signal transduction, cell cycle regulation, and apoptosis (programmed cell death). They are involved in the regulation of cell growth, differentiation, and survival under physiological conditions.

When proto-oncogene proteins undergo mutations or aberrations in their expression levels, they can transform into oncogenic forms, leading to uncontrolled cell growth and division. These altered proteins are then referred to as oncogene products or oncoproteins. Oncogenic mutations can occur due to various factors, including genetic predisposition, environmental exposures, and aging.

Examples of proto-oncogene proteins include:

1. Ras proteins: Involved in signal transduction pathways that regulate cell growth and differentiation. Activating mutations in Ras genes are found in various human cancers.
2. Myc proteins: Regulate gene expression related to cell cycle progression, apoptosis, and metabolism. Overexpression of Myc proteins is associated with several types of cancer.
3. EGFR (Epidermal Growth Factor Receptor): A transmembrane receptor tyrosine kinase that regulates cell proliferation, survival, and differentiation. Mutations or overexpression of EGFR are linked to various malignancies, such as lung cancer and glioblastoma.
4. Src family kinases: Intracellular tyrosine kinases that regulate signal transduction pathways involved in cell proliferation, survival, and migration. Dysregulation of Src family kinases is implicated in several types of cancer.
5. Abl kinases: Cytoplasmic tyrosine kinases that regulate various cellular processes, including cell growth, differentiation, and stress responses. Aberrant activation of Abl kinases, as seen in chronic myelogenous leukemia (CML), leads to uncontrolled cell proliferation.

Understanding the roles of proto-oncogene proteins and their dysregulation in cancer development is essential for developing targeted cancer therapies that aim to inhibit or modulate these aberrant signaling pathways.

I'm not aware of a specific medical definition for "Avian Proteins." The term "avian" generally refers to birds or their characteristics. Therefore, "avian proteins" would likely refer to proteins that are found in birds or are produced by avian cells. These proteins could have various functions and roles, depending on the specific protein in question.

For example, avian proteins might be of interest in medical research if they have similarities to human proteins and can be used as models to study protein function, structure, or interaction with other molecules. Additionally, some avian proteins may have potential applications in therapeutic development, such as using chicken egg-derived proteins for wound healing or as vaccine components.

However, without a specific context or reference, it's difficult to provide a more precise definition of "avian proteins" in a medical context.

POL1 (Polymerase 1) Transcription Initiation Complex Proteins are a set of proteins that come together to form the initiation complex for the transcription of ribosomal RNA (rRNA) genes in eukaryotic cells. The POL1 complex includes RNA polymerase I, select transcription factors, and other regulatory proteins. This complex is responsible for the transcription of rRNA genes located within the nucleolus, a specialized region within the cell nucleus. Proper assembly and functioning of this initiation complex are crucial for the production of ribosomes, which play a critical role in protein synthesis.

SOXB1 transcription factors are a subgroup of the SOX (SRY-related HMG box) family of transcription factors, which are characterized by a conserved high mobility group (HMG) box DNA-binding domain. The SOXB1 subfamily includes SOX1, SOX2, and SOX3, which play crucial roles during embryonic development and in the maintenance of stem cells. They regulate gene expression by binding to specific DNA sequences and interacting with other transcription factors and cofactors. SOXB1 proteins have been implicated in various biological processes, such as neurogenesis, eye development, and sex determination. Dysregulation of SOXB1 transcription factors has been associated with several human diseases, including cancer.

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.

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.

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.

A pyogenic granuloma is not precisely a "granuloma" in the strict medical definition, which refers to a specific type of tissue reaction characterized by chronic inflammation and the formation of granulation tissue. Instead, a pyogenic granuloma is a benign vascular tumor that occurs most frequently on the skin or mucous membranes.

Pyogenic granulomas are typically characterized by their rapid growth, bright red to dark red color, and friable texture. They can bleed easily, especially when traumatized. Histologically, they consist of a mass of small blood vessels, surrounded by loose connective tissue and inflammatory cells.

The term "pyogenic" is somewhat misleading because these lesions are not actually associated with pus or infection, although they can become secondarily infected. The name may have originated from the initial mistaken belief that these lesions were caused by a bacterial infection.

Pyogenic granulomas can occur at any age but are most common in children and young adults. They can be caused by minor trauma, hormonal changes, or underlying medical conditions such as pregnancy or vasculitis. Treatment typically involves surgical excision, although other options such as laser surgery or cauterization may also be used.

Membrane proteins are a type of protein that are embedded in the lipid bilayer of biological membranes, such as the plasma membrane of cells or the inner membrane of mitochondria. These proteins play crucial roles in various cellular processes, including:

1. Cell-cell recognition and signaling
2. Transport of molecules across the membrane (selective permeability)
3. Enzymatic reactions at the membrane surface
4. Energy transduction and conversion
5. Mechanosensation and signal transduction

Membrane proteins can be classified into two main categories: integral membrane proteins, which are permanently associated with the lipid bilayer, and peripheral membrane proteins, which are temporarily or loosely attached to the membrane surface. Integral membrane proteins can further be divided into three subcategories based on their topology:

1. Transmembrane proteins, which span the entire width of the lipid bilayer with one or more alpha-helices or beta-barrels.
2. Lipid-anchored proteins, which are covalently attached to lipids in the membrane via a glycosylphosphatidylinositol (GPI) anchor or other lipid modifications.
3. Monotopic proteins, which are partially embedded in the membrane and have one or more domains exposed to either side of the bilayer.

Membrane proteins are essential for maintaining cellular homeostasis and are targets for various therapeutic interventions, including drug development and gene therapy. However, their structural complexity and hydrophobicity make them challenging to study using traditional biochemical methods, requiring specialized techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and single-particle cryo-electron microscopy (cryo-EM).

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.

The diencephalon is a term used in anatomy to refer to the part of the brain that lies between the cerebrum and the midbrain. It includes several important structures, such as the thalamus, hypothalamus, epithalamus, and subthalamus.

The thalamus is a major relay station for sensory information, receiving input from all senses except smell and sending it to the appropriate areas of the cerebral cortex. The hypothalamus plays a crucial role in regulating various bodily functions, including hunger, thirst, body temperature, and sleep-wake cycles. It also produces hormones that regulate mood, growth, and development.

The epithalamus contains the pineal gland, which produces melatonin, a hormone that helps regulate sleep-wake cycles. The subthalamus is involved in motor control and coordination.

Overall, the diencephalon plays a critical role in integrating sensory information, regulating autonomic functions, and modulating behavior and emotion.

Culture techniques are methods used in microbiology to grow and multiply microorganisms, such as bacteria, fungi, or viruses, in a controlled laboratory environment. These techniques allow for the isolation, identification, and study of specific microorganisms, which is essential for diagnostic purposes, research, and development of medical treatments.

The most common culture technique involves inoculating a sterile growth medium with a sample suspected to contain microorganisms. The growth medium can be solid or liquid and contains nutrients that support the growth of the microorganisms. Common solid growth media include agar plates, while liquid growth media are used for broth cultures.

Once inoculated, the growth medium is incubated at a temperature that favors the growth of the microorganisms being studied. During incubation, the microorganisms multiply and form visible colonies on the solid growth medium or turbid growth in the liquid growth medium. The size, shape, color, and other characteristics of the colonies can provide important clues about the identity of the microorganism.

Other culture techniques include selective and differential media, which are designed to inhibit the growth of certain types of microorganisms while promoting the growth of others, allowing for the isolation and identification of specific pathogens. Enrichment cultures involve adding specific nutrients or factors to a sample to promote the growth of a particular type of microorganism.

Overall, culture techniques are essential tools in microbiology and play a critical role in medical diagnostics, research, and public health.

Diosmin is a type of flavonoid, which is a class of plant pigments that are known for their antioxidant properties. It is found naturally in various plants, including citrus fruits, and is often extracted and concentrated for use as a dietary supplement or medication. Diosmin has been studied for its potential benefits in treating conditions such as venous insufficiency, hemorrhoids, and lymphedema.

In medical terms, diosmin is often prescribed to improve the symptoms of chronic venous insufficiency, a condition in which the veins in the legs have difficulty returning blood to the heart. Diosmin has been shown to help improve the tone of the veins and reduce inflammation, which can help alleviate symptoms such as swelling, pain, and fatigue in the legs.

Diosmin is typically taken orally in the form of a tablet or capsule, and may be prescribed alone or in combination with other medications. As with any medication or supplement, it's important to follow your healthcare provider's instructions carefully when taking diosmin.

Germ layers refer to the primary layers of cells that form during embryonic development and give rise to the various tissues and organs in the body. In humans, there are three germ layers: the ectoderm, mesoderm, and endoderm. Each germ layer differentiates into distinct cell types and structures during the process of gastrulation. The ectoderm gives rise to the nervous system, sensory organs, and skin; the mesoderm forms muscles, bones, blood vessels, and the circulatory system; and the endoderm develops into the respiratory and digestive systems, including the lungs, liver, and pancreas.

Frizzled receptors are a type of cell surface receptor that are involved in the Wnt signaling pathway. They are named after the Drosophila melanogaster (fruit fly) mutant phenotype "frizzy" because of their role in regulating cell fate and patterning during development.

Frizzled receptors are composed of a seven-pass transmembrane domain, an extracellular cysteine-rich domain, and an intracellular tail. They bind to Wnt ligands, which are secreted proteins that play important roles in cell-cell communication during development and tissue homeostasis.

There are ten different Frizzled receptors identified in humans (FZD1-10) that can activate multiple signaling pathways, including the canonical Wnt/β-catenin pathway, noncanonical planar cell polarity pathway, and the Wnt/Ca2+ pathway. Dysregulation of Frizzled receptors has been implicated in various diseases, such as cancer, neurodevelopmental disorders, and metabolic disorders.

Herpes Simplex Virus Protein Vmw65, also known as Infected Cell Protein 0 (ICP0), is a crucial regulatory protein of the Herpes Simplex Virus (HSV). It is a viral early protein, which means it becomes active during the initial stages of viral replication.

Vmw65 plays a significant role in the virus's ability to evade the host's immune response and promote viral replication. It functions as a transcriptional regulator, affecting the expression of various genes involved in the host's antiviral defense mechanisms. Vmw65 can induce the degradation of certain cellular proteins that inhibit viral replication and also enhance viral gene expression by promoting viral DNA synthesis.

The protein's name, Vmw65, is derived from its molecular weight (65 kilodaltons) and its initial discovery as a virus-induced membrane protein. However, it's now more commonly referred to as ICP0 due to its role as an immediate-early viral gene product that functions as a transcriptional regulatory protein.

Annu Rev Cell Dev Biol. 20: 285-308. R.L. Gimlich and J. Gerhart (1984). Early cellular interactions promote embryonic axis ... The Spemann-Mangold organizer is important to developmental biology because it was the first proof that particular cell ... or destined cell types, of adjacent cells. This process in turn determines what tissues the adjacent cells will form. ... This center predisposes cells in the blastula stage to become neural tissue. The cells of the BCNE region give rise to the ...
Once blastoderm cells have covered almost half of the yolk cell, thickening throughout the margin of deep cells occurs. The ... Wnt8 induces ventral, lateral, and posterior regions of embryonic tissue. Wnt also has inhibitors like noggin to allow for the ... In order to aid in proper development fish have an organizer center called the Nieuwkoop center. Anterior and posterior axis ... Presumptive ectoderm or epiblast cells do not internalize but the deep cells (inner layer of cells) do and they become the ...
The 1935 prize was awarded to Hans Spemann "for his discovery of the organizer effect in embryonic development". In 1991 Howard ... On the other hand, Ramón y Cajal described nervous system as composed of interlinking nerve cells or neurons as suggested by a ... Organizers said that the prize had no relation to the Chinese government, the Ministry of Culture or Beijing Normal University ... "Ethel Browne, Hans Spemann, and the Discovery of the Organizer Phenomenon," Biol. Bull., v.181, pp.72-80 (Aug. 1991), cited by ...
Cell 91, 407-416. Lee, H.X., Ambrosio, A.L., Reversade, B. and De Robertis, E.M. (2006). Embryonic dorsal-ventral signaling: ... a novel dorsalizing factor activated by organizer-specific homeobox genes. Cell 79, 779-790. Piccolo, S., Sasai, Y., Lu, B. and ... a novel dorsalizing factor activated by organizer-specific homeobox genes". Cell. 79 (5): 779-790. doi:10.1016/0092-8674(94) ... Cell. 124 (1): 147-159. doi:10.1016/j.cell.2005.12.018. ISSN 0092-8674. PMC 2486255. PMID 16413488. De Robertis Laboratory Home ...
This signaling results in a region of cells known as the grey crescent, which is a classical organizer of embryonic development ... December 2003). "A novel cell-cell junction system: the cortex adhaerens mosaic of lens fiber cells". Journal of Cell Science. ... These cell-cell adhesion complexes are necessary for the creation and maintenance of epithelial cell layers and barriers. As a ... "Ksp-cadherin is a functional cell-cell adhesion molecule related to LI-cadherin". Experimental Cell Research. 294 (2): 345-355 ...
"Vertebrate Embryonic Cells Will Become Nerve Cells Unless Told Otherwise". Cell. 88 (1): 13-17. doi:10.1016/S0092-8674(00)81853 ... This dorsalizing signal allows for the Spemann organizer to become established in the dorsal marginal cells where the future ... Muñoz-Sanjuán, Ignacio; Brivanlou, Ali H. (2002-04-01). "Neural induction, the default model and embryonic stem cells". Nature ... A Novel Dorsalizing Factor Activated by Organizer-Specific Homeobox Genes". Cell. 79 (5): 779-790. doi:10.1016/0092-8674(94) ...
... initially called Organiser Programming Language Spemann-Mangold organizer, also called embryonic induction, a cell or tissue ... Look up organizer in Wiktionary, the free dictionary. Organizer may refer to: Community organizer, an advocate leading or ... Personal organizer, a type of diary Electronic organizer, an electronic version of an organizer Open Programming Language, ... which sends signals to other cells to instruct the fate of these cells Organizer box Organization (disambiguation) Organizing ( ...
The node cells do not express the composition of organizer-inducing factors present in the posterior marginal zone and in the ... Overview at Northwestern University Embryonic+Organizers at the U.S. National Library of Medicine Medical Subject Headings ( ... these endodermal cells migrate anteriorly and eventually displace the hypoblast cells, causing the hypoblast cells to be ... Cell fate studies have revealed that also the overall temporal sequence in which groups of endomesodermal cells internalize ...
... including involvement in public policy for biomedical issues involving recombinant DNA and embryonic stem cells and publishing ... He was also an organizer of the Asilomar conference on recombinant DNA in 1975. The previous year, Berg and other scientists ...
"Induction of Embryonic Primordia by Implantation of Organizers from a Different Species." After earning her PhD in zoology, ... The general effect she demonstrated is known as embryonic induction, that is, the capacity of some cells to direct the ... 1935 Nobel Prize in Physiology or Medicine for the discovery of the embryonic organizer, "one of the very few doctoral theses ... "Spemann and Mangold's Discovery of the Organizer". "Hilde Mangold (1898-1924) , The Embryo Project Encyclopedia". embryo.asu. ...
September 2001). "Dickkopf1 is required for embryonic head induction and limb morphogenesis in the mouse". Developmental Cell. ... "Spatially distinct head and heart inducers within the Xenopus organizer region". Current Biology. 9 (15): 800-9. doi:10.1016/ ... "Dickkopf Wnt signaling pathway inhibitor 1 regulates the differentiation of mouse embryonic stem cells in vitro and in vivo". ... "The Wnt signaling inhibitor dickkopf-1 is required for reentry into the cell cycle of human adult stem cells from bone marrow ...
June 2013). "Human embryonic stem cells derived by somatic cell nuclear transfer". Cell. 153 (6): 1228-38. doi:10.1016/j.cell. ... De Robertis EM (April 2006). "Spemann's organizer and self-regulation in amphibian embryos". Nature Reviews. Molecular Cell ... The similar network also controls embryonic stem cell self-renewal but is associated with distinct embryonic stem cell-specific ... November 2013). "The self-renewal of mouse embryonic stem cells is regulated by cell-substratum adhesion and cell spreading". ...
These cells express goosecoid consistent with their role as the organizer. The function of the organizer in chick embryos is ... The embryonic shield has the same function as the dorsal lip of the blastopore and acts as the organizer. When transplanted, it ... There are two cells, the P1 cell and the AB cell. The P1 cell was able make all of its fated cells while the AB cell could only ... At the two cell stage, the anterior cell is the AB cell while the posterior cell is the P1 cell. The dorsal/ventral axis of the ...
1935 The Organizer-Effect in Embryonic Development (Pages using the Phonos extension, Webarchive template wayback links, CS1: ... He succeeded in dividing the cells with a noose of baby hair. Spemann found that one half could indeed form a whole embryo, but ... His theory of embryonic induction by organisers is described in his book Embryonic Development and Induction (1938). He died of ... Spemann called these areas "organiser centres" or "organisers". Later he showed that different parts of the organiser centre ...
... that was determined prior to the other embryonic tissue and influenced the determination of surrounding cells. To test this ... Initial organizer cells migrate and localize anteriorly. The organizer cells are subdivided into head, trunk, and tail ... Goosecoid was the first organizer gene discovered, providing "the first visualization of Spemann-Mangold organizer cells and of ... the introduction of the organizer provided evidence that the fate of cells can be influenced by factors from other cell ...
Beddington, R. S.; Robertson, E. J. (1989). "An assessment of the developmental potential of embryonic stem cells in the ... including two years as co-organiser with Robertson. Beddington was the meetings secretary for the British Society for ... Studies on cell fate and cell potency in the postimplantation mammalian embryo. 1981. Beddington, R. S. (1994). "Induction of a ... the potential of embryonic stem cells for the study of genetic manipulation after demonstrating the ability of these cells to ...
... including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGF-8 is important and ... "organizer" in development, like the Spemann organizer" of the gastrulating embryo. FGF-8 is expressed in the region where Otx2 ... Lastly, the ability for FGF8 to regulate cell proliferation has caused interest in its effects on tumors or squamous cell ... Loss of Tbx1 and Tfap2 can result in proliferation and apoptosis in the palate cells increasing the risk of CLP. Overexpression ...
He developed methods to guide human embryonic stem cells (hESCs) into forming brain cortex, eyes (optic cups), and other organs ... A novel dorsalizing factor activated by organizer-specific homeobox genes". Cell. 79 (5): 779-90. doi:10.1016/0092-8674(94) ... In 2012, Sasai became the first stem cell researcher to grow an optic cup from human cells. In 2014 Sasai was a co-author on ... March 31, 2014) Report on STAP Cell Research Paper Investigation. riken.jp "Stem cell debacle déjà vu". Bio Edge. April 6, 2014 ...
Later on in embryonic development, Fgf8 expression localizes to the rostral most Gbx2 expressing cells (caudal region of the ... The isthmic organizer, or isthmus organizer, also known as the midbrain−hindbrain boundary (MHB), is a secondary organizer ... In cells that express both Otx2 and Irx1, En1 is activated by Fgf8 signaling. En1 expression in cells that express both Pax2 ... Fgf8 expression leads to the activation of En1 in cells that express both Irx1 and Otx2. Fgf8 was shown to be an organizing ...
Katoh M, Katoh M (May 2006). "CER1 is a common target of WNT and NODAL signaling pathways in human embryonic stem cells". ... Schneider VA, Mercola M (August 1999). "Spatially distinct head and heart inducers within the Xenopus organizer region". ... More specifically, Nodal inhibits certain cells from joining cardiogenesis while simultaneously activating cells. The cells ... In human embryonic development, Cerberus and the protein coded by GREM3 inhibit NODAL in the Wnt signaling pathway during the ...
... predisposes to preeclampsia and is needed for the self-renewal of human embryonic stem cells. Analogues of Elabela have entered ... Bmp7 and Spemann organizer signals induces massive brain formation in Xenopus embryos". Development. 132 (15): 3381-92. doi: ... 2015-10-01). "ELABELA Is an Endogenous Growth Factor that Sustains hESC Self-Renewal via the PI3K/AKT Pathway". Cell Stem Cell ... Cell. 167 (1): 187-202.E17. doi:10.1016/j.cell.2016.09.001. PMID 27662089. Zhonga, Franklin L.; Robinson, Kim; Teo, Daniel Eng ...
"Neural specification from human embryonic stem cells". In Odorico, John S.; et al. (eds.). Human embryonic stem cells. Garland ... It is important to note that while the organizer is the dorsal lip of the blastopore, this is not one set of cells but rather ... Neural crest cells will migrate through the embryo and will give rise to several cell populations, including pigment cells and ... At any given time during gastrulation there will be different cells that make up the organizer. Subsequent work on inducers by ...
The ECM does not play a major role in spinal neurulation due to the close-packed nature of the mesodermal cells in the spinal ... For example, in reptiles, extra-embryonic membrane tissues become distinct from the embryo. The neurula embryo has five regions ... Stern, Claudio D. (February 2001). "Initial Patterning of the Central Nervous System: How Many Organizers?" (PDF). Nature ... The outer ectodermal layer of the neurula is formed by uniform expansion of the cells at the animal pole, known as the animal ...
Niehrs, C. (2001). "MEDAL REVIEW: The Spemann organizer and embryonic head induction". The EMBO Journal. 20 (4): 631-637. doi: ... On transferring genes into stem cells and mice". The EMBO Journal. 9 (10): 3024-32. doi:10.1002/j.1460-2075.1990.tb07498.x. PMC ... Briscoe, J. (2009). "Making a grade: Sonic Hedgehog signalling and the control of neural cell fate". The EMBO Journal. 28 (5): ... Gorlich, D. (1998). "Transport into and out of the cell nucleus". The EMBO Journal. 17 (10): 2721-2727. doi:10.1093/emboj/17.10 ...
The microtubules and microfilaments are in mechanical opposition in a proposed embryonic organelle they called the cell state ... more complex than predicted in the original model however it did originate from the precise location of the Spemann organizer ... If the cell has experienced contraction, one signal is sent and if the cell has experienced expansion then another signal is ... Ultrastructural analysis of the cell state splitter in ectoderm cells differentiating to neural plate and epidermis during ...
... away from the embryonic pole, to line the blastocoele, the remaining cells of the inner cell mass, situated between the ... The primitive node is situated at the anterior end of the primitive streak and serves as the organizer for gastrulation, ... During gastrulation, migrating epiblast cells undergo epithelial-mesenchymal transition in order to lose cell-cell adhesion (E- ... "The Role of Laminin in Embryonic Cell Polarization and Tissue Organization". Developmental Cell. 4 (5): 613-624. doi:10.1016/ ...
Lambert, J. David (2008). "Mesoderm in spiralians: the organizer and the 4d cell". Journal of Experimental Zoology Part B: ... Lambert, J. David; Nagy, Lisa M. (2001). "MAPK signaling by the D quadrant embryonic organizer of the mollusc Ilyanassa ... It is reported that micromere 2d, a cell that is born when the embryo has 16 cells, has organizing activity which enables it to ... During this time, cell proliferation patterns are different from uncut animals; while cell proliferation is still observed ...
If cell movement in the PMZ is blocked, the primitive streak does not form. Thus, the PMZ acts as an organizer. Cells in ... and from this they demonstrated the fact that embryonic regulation is a result of the spatial distribution of Koller's sickle ... "The homeobox gene goosecoid and the origin of organizer cells in the early chick blastoderm". Cell. 74 (4): 645-59. doi:10.1016 ... They determined that cells move to the center of the epiblast following the activation of the Wnt planar cell polarity pathway ...
Otx2 is a group of homeobox genes that are typically described as a head organizer in the primitive streak stage of embryonic ... High Otx2 levels induce photoreceptor cell fate but not bipolar cell fate. Low levels of Otx2 impair bipolar cell maturation ... Otx2 is an intrinsic determinant of the embryonic stem cell state and is required for transition to a stable epiblast stem cell ... Otx2 is a key regulator of the earliest stages of ES cell differentiation. The ectopic expression of Otx2 drives ES cells into ...
... a novel dorsalizing factor activated by organizer-specific homeobox genes". Cell. 79 (5): 779-90. doi:10.1016/0092-8674(94) ... is a protein with a prominent role in dorsal-ventral patterning during early embryonic development. In humans it is encoded for ... In the chick embryo it is expressed in the anterior cells of Koller's sickle, which form the anterior cells of the primitive ... It was first hypothesized that chordin plays a role in the dorsal homeobox genes in Spemann's organizer. The chordin gene was ...
Current Opinion in Cell Biology, a European Research Council (ERC) panel member and an organiser of the international ... "The cis-regulatory dynamics of embryonic development at single-cell resolution". Nature. 555 (7697): 538-542. Bibcode:2018Natur ... "Editorial Board: Developmental Cell". cell.com. "Editors and Board , Development". dev.biologists.org. "Editors & Board , ... "Flyer Online Symposium Minerva-Gentner Symposium 2020" (PDF). "Speaker - Cell Symposia: Transcriptional Regulation". cell- ...
Chaperone-enriched protein aggregates stay insoluble and protect cells from age-accelerating toxicity. ... Muscle cell of a long-lived nematode worm: chaperone-rich protein aggregates (green) accumulate and save the cell during aging ... Worse, cells that burden themselves with toxic protein aggregates age more quickly. In the case of neural cells, protein ... In the cell, the dumpster-or rather the sequestered protein hoard-is never actually carted away. Still, concentrating harmful ...
Women in Science: Hilde Mangold and the embryonic organizer (1898-1924). Hilde Mangold was born October 20, 1898. She was a ... The stiffness of stem cells. What causes stiffness factor in induced pluripotent stem cells and what are the functional ... Tuning in to the inner earBasile Tarchini, Ph.D., is working to understand the basic mechanisms underlying hair cell ...
Annu Rev Cell Dev Biol. 20: 285-308. R.L. Gimlich and J. Gerhart (1984). Early cellular interactions promote embryonic axis ... The Spemann-Mangold organizer is important to developmental biology because it was the first proof that particular cell ... or destined cell types, of adjacent cells. This process in turn determines what tissues the adjacent cells will form. ... This center predisposes cells in the blastula stage to become neural tissue. The cells of the BCNE region give rise to the ...
The scope of the conference ranges from embryonic induction and the gastrula organizer itself to its signaling systems, cell ... stem cells and synthetic organizers, self-organization in development, plant organizers.. The deadline to submit contributions ... This special issue will be open to contributions from scientists working on the gastrula organizer, gastrulation cell behaviour ... The concept of embryonic induction, first demonstrated in the famous gastrula organizer transplantation experiments by Hilde ...
... we reviewed current emerging organ generation technologies and the associated efficiency of chimera formation in human cells ... we reviewed current emerging organ generation technologies and the associated efficiency of chimera formation in human cells ... "organizer" concept and its role in gastrulation, known as embryonic differentiation. When transplanted into another, a portion ... 2021). Derivation of intermediate pluripotent stem cells amenable to primordial germ cell specification. Cell Stem Cell 28, 550 ...
STEM CELL LEGISLATION BACK. The US Senate has once again passed a bill to allow federal dollars to fund embryonic stem cell ... Organizers stress that today is only one action in their campaign to make the local administration end homelessness in Los ... Camilo Romero is an organizer with the Coalition: (Camilo) "Were currently in the middle of a march through skid row, up to ... The AFL-CIOs Farm Labor Organizing Committee, or FLOC, says the brutal beating death of Mexican organizer Santiago Rafael Cruz ...
... a single fertilized cell progresses through multiple rounds of cell division. Eventually, the clump of cells goes through a ... groups of cells that coalesce early during the embryonic life of all animals except maybe sponges, and from which organs and ... On the induction of Embryonic Primordia by Implantation of Organizers from a Different Species]. Berlin: Springer, 1924. ... a single fertilized cell progresses through multiple rounds of cell division. Eventually, the clump of cells goes through a ...
Mangold conducted research for her dissertation On the Induction of Embryonic Primordia by Implantation of Organizers from ... When two embryos are correctly joined before the 32-cell stage, the embryo will develop normally and exhibit a mosaic pattern ... On the Induction of Embryonic Primordia by Implantation of Organizers from Different Species (1924), Hilde Mangolds ... New York, Wilson studied what causes cells to differentiate during. development. In 1904 he conducted his experiments on ...
Cell polarization is essential during gastrulation, driving asymmetric cell division, cell movements, and cell shape changes. ... The furry (fry) gene encodes an evolutionarily conserved protein with a wide variety of cellular functions, including cell ... Loss of Fry function drastically affects the movement and morphological polarization of cells during gastrulation and disrupts ... Gastrulation is a key event in animal embryogenesis during which germ layer precursors are rearranged and the embryonic axes ...
A comprehensive resource based on analysis of the responses of embryonic ectoderm cells to signals from the organizer (the ... A human endogenous fusogen, syncytin, which facilitates placental cell-cell fusion during early embryonic development, mediates ... Single-cell analysis reveals dynamics of human B cell differentiation and identifies novel B and antibody-secreting cell ... Cell circuits between leukemic cells and mesenchymal stem cells block lymphopoiesis by activating lymphotoxin beta receptor ...
... including formation of isthmic organizer characteristics. Single-cell transcriptomics revealed that rostro-caudal organization ... Here, we model early human neural tube development using human embryonic stem cells cultured in a microfluidic device. The ... approach, named microfluidic-controlled stem cell regionalization (MiSTR), exposes pluripotent stem cells to signaling ... and that the first markers of a neural-specific transcription program emerged in the rostral cells at 48 h. The transcriptomic ...
Embryonic Cells using CE-ESI-MS". Sam Choi, University of Maryland, College Park (Advisor: Peter Nemes), 2nd place: "Detection ... Jie Li, University of Maryland (Advisor: Peter Nemes), 3rd place: "In "Proteo-Metabolomics of Spemanns Organizer in the ... Single Cell Mass Spectrometry Reveals Cell Heterogeneity in the 16 cell Frog (Xenopus laevis) Embryo ... "In Vivo Subcellular Mass Spectrometry Enables Systems Biology in Single Embryonic Cells" ...
The model produces results similar to embryonic brain development at five weeks post-fertilization. ... Researchers have developed a new model of early embryonic brain development. The model, called MiSTR, allows researchers to ... including formation of isthmic organizer characteristics. Single-cell transcriptomics revealed that rostro-caudal organization ... Stem cell researchers at Lund University in Sweden have developed a new research model of the early embryonic brain. The aim of ...
Organ size is limited by the number of embryonic progenitor cells in the pancreas but not the liver. 2007, Pubmed Thomas, Hex: ... A gene regulatory network controlling hhex transcription in the anterior endoderm of the organizer. 2011, Pubmed , Xenbase Ruiz ... Distinct populations of endoderm cells converge to generate the embryonic liver bud and ventral foregut tissues. 2005, Pubmed ... 3. Ectopic hhex converts intestine-forming cells into vpp1-expressing cells. Whole mount staining was performed with probes ...
Molecular organisation and embryonic expression of the hedgehog gene involved in cell-cell communication in segmental ... Clones of cells mutant for sgg/zw3 express Dll in a cell autonomous manner (Fig. 1E). Clones of sgg/zw3 mutant cells adopt wing ... Making a difference: the role of cell-cell interactions in establishing separate identities for equivalent cells ... an asym-metric cell signal is transmitted at the interface between the two cell populations. Cells in the posterior compartment ...
Gastrula organiser and embryonic patterning in the mouse. . Semin. Cell Dev. Biol. ... Goosecoid promotes head organizer activity by direct repression of Xwnt8 in Spemanns organizer ... WNT-planar cell polarity (WNT-PCP; for controlling cell shape and tissue remodelling) and WNT-calcium pathways [for calcium ... which affects cell adhesion and the maintenance of epithelial architecture of the neuroepithelium, and triggers cell death ...
It uses the tricolor flag of France to show that the embryonic cells create similar patterns using genetic code even when a ... Spemann, H., Mangold, H. Induction of embryonic primordial by implantation of organizers from a different species. Rouxs Arch ... as well as cell fate during development. She and colleague Eric Wieschaus identified the key genes responsible for embryonic ... His thesis was on imaginal disc cells. Overall, when she began working in this lab with Wieschaus she discovered new ways of ...
Signals from the yolk cell induce mesoderm, neuroectoderm, the trunk organizer, and the noto-chord in zebrafish. Dev Biol 215: ... as well as to clarify the pluripotency of embryonic cells in several developmental stages to use donor cells. ... At 15 hpf, the blastoderm covered the yolk cell completely.. Figure 4. Germ ring and embryonic shield formation in the early ... Thereafter, epiboly started and a blastoderm covered over the yolk cell at 8 hpf. At 10 hpf, the germ ring and the embryonic ...
... and comprehensive study of the abundance levels of histone PTMs during the differentiation of mouse embryonic stem cells (ESCs ... our data demonstrate the fundamental role of Brd4 in monitoring cell differentiation through its interaction with acetylated ... Pluripotent cells can be differentiated into many different cell types in vitro. Successful differentiation is guided in large ... Wnt3 and Wnt3a are required for induction of the mid-diencephalic organizer in the caudal forebrain. Neural Dev. 2012;7:12. ...
5E). In embryos with cells transplanted to region IV, graft-derived cells were mostly found in the embryonic heart. These ... Recruitment of cells to the gastrula organizer. Analysis of the developmental fates of the cells of the gastrula organizer ... An organizer cell population is present throughout gastrulation. Cell populations that display organizer activity have ... Changes in cell fate and molecular properties point to a dynamic cell population in the gastrula organizer.. Results of our ...
This is likely the result of the construction of cell surface signaling domains (rafts), of which GM1 is a major organizer ( ... In embryonic neurons, Neu3 sialidase action can affect axons by increasing TrkA signaling resulting in ERK activation (Da Silva ... 2011) Effects of integrin-mediated cell adhesion on plasma membrane lipid raft components and signaling. Mol Biol Cell 22:3456- ... 1997) Expression of cell adhesion molecules in normal nerves, chronic axonal neuropathies and Schwann cell tumors. J Neurol Sci ...
... guiding newly formed progenitor cell groups to the differentiation site. ... maintains the boundary of dorsal forerunner cell cluster during morphogenesis of the zebrafish embryonic left-right organizer ... Cell tracking. Request a detailed protocol Cell movement was tracked by following the cells centre in Tg(sox17::GFP) embryos, ... Dorsal forerunner cells (DFCs) increase cell-cell contact and cluster compaction during vegetal movement.. (A) Dorsal view of a ...
In their organization into cells, which are self-replicating systems, the individual molecules and cell particles have acquired ... The great German embryologist Hans Spemann thought he was on the track of the chemical organizers of development until his ... The other has been from biologists who study either the central nervous system or embryonic development, fields which have made ... It is as if each cell had within it the information "limb" without knowing whether it is to be toe or shank, muscle, bone, or ...
... that arises from basal cells (ie, small, round cells found in the lower layer of the epidermis). The prognosis for patients ... Basal cell carcinoma (BCC) is a nonmelanocytic skin cancer (ie, an epithelial tumor) ... Nucleolar organizer region staining patterns in paraffin-embedded tissue cells from human skin cancers. J Cutan Pathol. 2005 ... Correlation of embryonic fusion planes with the anatomical distribution of basal cell carcinoma. Dermatol Surg. 2007 Aug. 33(8 ...
Quantitative description of microRNA target site occupancy in mouse embryonic stem cells and derived cells of neuronal lineage. ... Bodnar, M. S., Spector, D. L. (June 2013) Chromatin Meets Its Organizers. Cell, 153 (6). pp. 1187-1189. ISSN 0092-8674 ... Mapping cellular hierarchy by single-cell analysis of the cell surface repertoire. Cell Stem Cell, 13 (4). pp. 492-505. ISSN ... Donnenberg, A. D., Hicks, J. B., Wigler, M., Donnenberg, V. S. (January 2013) The Cancer Stem Cell: Cell Type or Cell State? ...
The polarization of nascent embryonic fields and the endowment of cells with organizer properties are key to initiation of ... proliferation and differentiation of embryonic progenitor cells. In recent years, systems biology approaches have moved our ... Our analysis revealed that GLI3 directly restricts the expression of regulators of the G1-S cell-cycle transition such as Cdk6 ... Distal limb development and specification of digit identities in tetrapods are under the control of a mesenchymal organizer ...
Abstract title:Modeling Neuronal Toxicity for Parkinsons Disease with Human Embryonic Stem Cell-derived Dopaminergic Neurons. ... The venue provides a state-of-the-art learning environment, while conference organizers have planned informal social events to ... Stem Cells and Development. - IPS and Reprogramming. - Small Molecule Epigenetic Regulators. - Cancer Stem Cells and Therapy. ... Abstract title:Production of Islet Cells from Human ES Cells to Treat Diabetes. En Li, China Novartis Institutes for Biomedical ...
FOXJ1 is expressed in ciliated cells of the airways, testis, oviduct, central nervous system and the embryonic left-right ... Established genes often involve a ciliated, embryonic structure known as the left-right organizer (LRO). Herein, we focus on ... Hematopoietic stem cells (HSCs) continually regenerate blood cells. Acquisition of a somatic mutation that provides a selective ... Additionally, as the effector cells have been identified to be immune cells, there is ongoing interest in assessing whether ...
Organizers. Jianping Fu (University Of Michigan, Ann Arbor). Janet Rossant (Hospital for Sick Children, University of Toronto) ... Importantly, recent advances in generating human embryo-like structures from human pluripotent stem cells and in vitro cultured ... manifest during embryonic development. ... For Organizers*Add Participants. *Participant List Submission/ ...
Organizer: IRB Barcelona Date: Friday 26 November, 12PM Place: Auditorium Antoni Caparrós, PCB Title: SYNTHETIC DEVELOPMENTAL ... While mechanisms of embryonic development are well conserved among mammals, the progression speed tends to be slower in larger ... We found that this period difference between species stems from slower biochemical reactions in human cells, including slower ... Organizer: IRB Barcelona. Date: Friday 26 November, 12PM. Place: Auditorium Antoni Caparrós, PCB ...
  • TATA-box binding protein is not required for RNA Polymerase II transcription in mouse embryonic stem cells. (elifesciences.org)
  • Here, we present a quantitative and comprehensive study of the abundance levels of histone PTMs during the differentiation of mouse embryonic stem cells (ESCs) using mass spectrometry (MS). We observed dynamic changes of histone PTMs including increased H3K9 methylation levels in agreement with previously reported results. (biomedcentral.com)
  • The aim of the model is to study the very earliest stages of brain to understand how different regions in the brain are formed during embryonic development. (neurosciencenews.com)
  • Furthermore, titration of hhex with a dexamethasone-inducible hhex -VP16GR fusion construct suggested that endogenous hhex activity during gastrulation is essential for the formation of ventral pancreatic progenitor cells. (xenbase.org)
  • The developmental strategies used by progenitor cells to allow a safe journey from their induction place towards the site of terminal differentiation are still poorly understood. (elifesciences.org)
  • These early progenitor cells often travel long distances from their induction site to the site of terminal differentiation, making them vulnerable to environmental cues and movement of neighbouring tissues. (elifesciences.org)
  • Several embryonic tissues and organs originate from small sets of progenitor cells. (elifesciences.org)
  • Despite the importance of the developmental pathways followed by these small groups of progenitor cells and their impact on the physiology of the organism, we still know little about the set of developmental strategies that progenitor cells deploy in vivo to overcome the challenges imposed by the environment as they travel to the site of terminal differentiation. (elifesciences.org)
  • The molecular analysis of limb bud development in vertebrates continues to fuel our understanding of the gene regulatory networks that orchestrate the patterning, proliferation and differentiation of embryonic progenitor cells. (devgenbasel.com)
  • We compared five strategies in CD34+ hematopoietic stem and progenitor cells, using either Cas9 nuclease or adenine base editors. (cdc.gov)
  • The Self-Organization in Biology: Freiburg Spemann-Mangold Centennial Symposium celebrates 100 years of scientific advances rooted in Hilde Mangold's and Hans Spemann's discovery of the gastrula organizer in vertebrate development, published in 1924 and awarded the Nobel Prize in Physiology or Medicine in 1935. (elsevier.com)
  • The concept of embryonic induction, first demonstrated in the famous gastrula organizer transplantation experiments by Hilde Mangold and Hans Spemann in their 1924 landmark publication and awarded the Nobel Prize in Physiology or Medicine in 1935, has been the most influential discovery promoting 100 years of research into organization phenomena in biology. (elsevier.com)
  • The scope of the conference ranges from embryonic induction and the gastrula organizer itself to its signaling systems, cell behavior during gastrulation, morphogenesis and pattern formation. (elsevier.com)
  • This cell population can therefore be regarded as the mid-gastrula organizer and, together with the early-gastrula organizer and the node, constitute the organizer of the mouse embryo at successive stages of development. (silverchair.com)
  • Fine mapping of the epiblast in the posterior region of the early-streak stage embryo reveals that although the early-gastrula organizer contains cells that give rise to the axial mesoderm, the bulk of the progenitors of the head process and the notochord are localized outside the early gastrula organizer. (silverchair.com)
  • In the mid-gastrula organizer, early gastrula organizer derived cells that are fated for the prechordal mesoderm are joined by the progenitors of the head process that are recruited from the epiblast previously anterior to the early gastrula organizer. (silverchair.com)
  • Cells that are fated for the head process move anteriorly from the mid-gastrula organizer in a tight column along the midline of the embryo. (silverchair.com)
  • Other mid-gastrula organizer cells join the expanding mesodermal layer and colonize the cranial and heart mesoderm. (silverchair.com)
  • The dorsal gastrula organizer plays a fundamental role in establishment of the vertebrate axis. (zfin.org)
  • We demonstrate that the zebrafish bozozok (boz) locus is required at the blastula stages for formation of the embryonic shield, the equivalent of the gastrula organizer and expression of multiple organizer-specific genes. (zfin.org)
  • These studies provide genetic evidence for an essential function of a homeodomain protein in ß-catenin-mediated induction of the dorsal gastrula organizer and place boz at the top of a hierarchy of zygotic genes specifying the dorsal midline of a vertebrate embryo. (zfin.org)
  • Spemann's organizer and self-regulation in amphibian embryos. (wikipedia.org)
  • Rathke's results showed that these two cell layers existed in the embryos of non-vertebrate animals. (asu.edu)
  • In Hand2-deficient mouse embryos, the EMT underlying AVC cardiac cushion formation is disrupted, and we combined ChIP-seq of embryonic hearts with transcriptome analysis of wild-type and mutants AVCs to identify the functionally relevant HAND2 target genes. (devgenbasel.com)
  • Importantly, recent advances in generating human embryo-like structures from human pluripotent stem cells and in vitro cultured human embryos have led to exciting new human-related embryological models that are promising for advancing human embryology. (birs.ca)
  • E) Embryos were injected at the two-cell stage with mE2a-GFP- and RFP-tagged histone H2b mRNA and monitored for fluorescence at stage 10.5. (xenbase.org)
  • F) ChIP-qRT-PCR using anti-GFP antibodies in stage 10.5 embryos following mE2a-GFP injection at the two-cell stage. (xenbase.org)
  • These cells, taken from days' old embryos called blastocysts, have the ability to form any tissue in the body. (harvard.edu)
  • Embryos were injected at the 4-cell stage dorsally (A-C, double in situ hybridization for chordin and LacZ RNA as injection marker, in red), or 1 ​cell stage (D-R). Control embryos were injected solely with LacZ RNA (1 ​ng). (xenbase.org)
  • The Xenopus Nieuwkoop center and Spemann-Mangold organizer share molecular components and a requirement for maternal Wnt activity. (wikipedia.org)
  • Early cellular interactions promote embryonic axis formation in Xenopus laevis. (wikipedia.org)
  • The embryo of the frog Xenopus laevis is widely used as a model of cell polarization, migration, and morphogenesis due to its unique experimental advantages. (nature.com)
  • At the beginning of Xenopus gastrulation, the presumptive anterior mesoderm cells located at the dorsal marginal zone (DMZ) roll inward at the midline of the blastopore lip in a process called involution. (nature.com)
  • The cells of the BCNE region give rise to the forebrain, most of the mid-brain and hind-brain, the notochord, and the floor plate. (wikipedia.org)
  • Recent lineage tracing studies using Sonic Hedgehog (SHH) and Noto have exhibited that NCs and SNPCs are both derived from the embryonic notochord [13 14 Risbud and Shapiro suggest that the reduction in the number of large vacuolated NCs in adult IVDs is usually associated with a shift in roles of the NCs as they become organizer cells or otherwise. (bioinbrief.com)
  • Furthermore, boz is essential for specification of dorsoanterior embryonic structures, including notochord, prechordal mesendoderm, floor plate and forebrain. (zfin.org)
  • The Nieuwkoop center, named after the developmental biologist Pieter Nieuwkoop, is a cluster of dorsal vegetal cells in a blastula which produce both mesoderm-inducing and dorsalizing signals. (wikipedia.org)
  • Transplant of the Nieuwkoop Center causes formation of an embryonic axis with an endodermal fate which contains dorsal mesoderm. (wikipedia.org)
  • However, cells from the Nieuwkoop Center express potent mesoderm inducers as well as the secreted protein, Cerberus (CER1), which contributes to the formation of the head, heart, and asymmetry of internal organs. (wikipedia.org)
  • Eventually, the clump of cells goes through a stage called gastrulation, during which the embryo reorganizes itself into the three germ layers: endoderm, ectoderm, and mesoderm. (asu.edu)
  • Loss of Fry function drastically affects the movement and morphological polarization of cells during gastrulation and disrupts dorsal mesoderm convergent extension, responsible for head-to-tail elongation. (nature.com)
  • This Spemann-Mangold organizer was the first time that a developmental organizer region was identified and studied. (wikipedia.org)
  • The Spemann-Mangold organizer is important to developmental biology because it was the first proof that particular cell populations influenced the differentiation of other cells through signaling molecules. (wikipedia.org)
  • Signals from the Nieuwkoop center induce the Spemann-Mangold organizer, thus the Nieuwkoop Center is known as the organizer of the organizer. (wikipedia.org)
  • Even with the BCNE center (Blastula chordin and noggin expression center) removed from the blastula, the Nieuwkoop Center is able to induce formation of the Spemann-Mangold organizer. (wikipedia.org)
  • Gastrulation movements are orchestrated by a small, heterogeneous group of cells with inductive and morphogenetic properties located in the dorsal lip of the blastopore (DBL) of the amphibian gastrula known as the Spemann-Mangold organizer or dorsal organizer. (nature.com)
  • In amphibians, Spemann's organizer, which is homologous to the node, partially overlaps with anterior endoderm cells expressing homologues of the AVE markers cerberus, Hex and Hesx1. (nih.gov)
  • The approach, named microfluidic-controlled stem cell regionalization (MiSTR), exposes pluripotent stem cells to signaling gradients that mimic developmental patterning. (nature.com)
  • Pluripotent cells can be differentiated into many different cell types in vitro. (biomedcentral.com)
  • Embryonic stem cells (ESCs) are self-renewing, pluripotent cells derived from the inner cell mass (ICM) of a blastocyst [ 1 , 2 ]. (biomedcentral.com)
  • Histone acetylation has been implicated to be important for the pluripotent cell state, as some HDAC inhibitors have been shown to improve reprogramming efficiency of induced pluripotent stem cells (iPSCs) or maintain a pluripotent stem cell state. (biomedcentral.com)
  • We have recently recapitulated the segmentation clock, oscillatory gene expression during early development, from human and mouse pluripotent stem cells. (irbbarcelona.org)
  • Book] Cre/loxP, Flp/FRT systems and pluripotent stem cell lines. (nii.ac.jp)
  • Similarly, destruction of neonatally abundant pluripotent stem cells would likely have a more pervasive outcome than destruction of The value of incorporating immunologic appeared more severe and/or persistent when single lineages or differentiated cells that pre- data for the toxicologic assessment of drugs, the exposure occurred perinatally when com- dominate in adults. (cdc.gov)
  • The nuclear membrane protein SUN1 stabilizes endothelial cell-cell junctions far from the nucleus via regulation of microtubule dynamics and Rho GEF-H1 signaling, revealing long-range cellular communication important for vascular development and function. (elifesciences.org)
  • Here, we model early human neural tube development using human embryonic stem cells cultured in a microfluidic device. (nature.com)
  • Researchers have developed a new model of early embryonic brain development. (neurosciencenews.com)
  • The model produces results similar to embryonic brain development at five weeks post-fertilization. (neurosciencenews.com)
  • Studies on how each individual neural cell forms in the embryo during brain development are essential for the researchers to be able to understand how to produce these specific cells in the laboratory. (neurosciencenews.com)
  • Research on the early development of the human brain, from five days after the fertilisation of the cell to approximately seven weeks, have so far been difficult as researchers have not had access to human embryonic tissue from these early stages of development. (neurosciencenews.com)
  • For the first time, we now have access to tissue that resembles the early embryonic brain and can therefore study processes behind brain development in a way that has not been possible before. (neurosciencenews.com)
  • We can for instance use it for testing how chemical substances in our environment might impact on embryonic brain development. (neurosciencenews.com)
  • This will help to speed up the development of new stem cell treatments for neurological diseases. (neurosciencenews.com)
  • These observations suggest that, beyond its role in liver development, hhex controls specification of a vpp1 -positive endodermal cell population during gastrulation that is required for the formation of the ventral pancreas . (xenbase.org)
  • German biologist, Christiane Nusslein-Volhard is renowned for elucidation of the genetic control of embryonic development of fruit flies. (wepapers.com)
  • Throughout this paper I will detail the early career of Dr. Nusslein-Volhard and the ways in which her research helped to revolutionize the field of developmental biology as it pertains to embryonic development and gene analysis/function. (wepapers.com)
  • Early developmental staging from the zygote stage to the gastrula is a basic step for studying embryonic development and biotechnology. (bioone.org)
  • We described the early embryonic development of the loach, Misgurnus anguillicaudatus , based on morphological features and gene expression. (bioone.org)
  • The embryonic development of the loach resembled that of the zebrafish in terms of morphological change and gene expression. (bioone.org)
  • What Newton did for physics toward the end of the seventeenth century, and Lavoisier did for chemistry at the end of the eighteenth, was not carried out in biology until Darwin gave a mechanical explanation of evolution and the German school of Entwicklungsmechanik provided a physico-chemical model of embryonic development in the latter part of the nineteenth century. (nybooks.com)
  • During embryo development, naïve cell lineages undergo concurrent processes of fate specification and morphogenesis as critical steps towards the generation of differentiated tissues and organs. (elifesciences.org)
  • Here, we examine this question during the early stages of morphogenesis of the embryonic laterality organ, the first organ to form during vertebrate development, using the zebrafish as a model organism. (elifesciences.org)
  • Chromatin remodeling and genomic alterations impact spatio-temporal regulation of gene expression, which is central to embryonic development. (devgenbasel.com)
  • The key molecular interactions governing vertebrate limb bud development are a paradigm to study the mechanisms controlling progenitor cell proliferation and specification during vertebrate organogenesis. (devgenbasel.com)
  • Most of our current knowledge of mammalian embryology is derived from studies of the mouse embryo, leading to astonishing discoveries of self-organizing and emergent properties ("the laws of development") manifest during embryonic development. (birs.ca)
  • While mechanisms of embryonic development are well conserved among mammals, the progression speed tends to be slower in larger species. (irbbarcelona.org)
  • In mice, there is evidence suggesting that the development of head and trunk structures is organized by distinctly separated cell populations. (nih.gov)
  • We examined the response of granule cell precursors to the overexpression of Hoxa2 , which normally determines patterns of development specific to the hindbrain. (biomedcentral.com)
  • This is accomplished using the model of development and differentiation of cells of the immune system as well as during tumorigenesis to provide novel insights into the molecular mechanisms of such coordinated gene regulation. (sglabepigenetics.com)
  • The processes of T-cell development and differentiation are coordinated by a multitude of signaling processes and transcription factors that impart distinct functional properties on progenitors. (sglabepigenetics.com)
  • We have focused on understanding the role of 'Special AT-rich binding protein 1' (SATB1) in T-cell development and differentiation. (sglabepigenetics.com)
  • The sequential development of thymocytes is dependent on T-cell receptor (TCR) signaling and an array of transcription factors. (sglabepigenetics.com)
  • The furry ( fry ) gene encodes an evolutionarily conserved protein with a wide variety of cellular functions, including cell polarization and morphogenesis in invertebrates. (nature.com)
  • Separately, E2a is necessary to drive transcription of Smad2 /3 target genes, including critical regulators of dorsal cell fate and morphogenesis. (xenbase.org)
  • Following the specification of the compartments, an asym-metric cell signal is transmitted at the interface between the two cell populations. (biologists.com)
  • The profile of genetic activity and the tissue contribution by cells in the organizer change during gastrulation, suggesting that the organizer may be populated by a succession of cell populations with different fates. (silverchair.com)
  • A number of distinct neuronal populations are generated in r1, including cerebellar granule cells [ 2 ], the most populous neuron in the vertebrate CNS. (biomedcentral.com)
  • Out of the thousands of protein-coding 'genes' or DNA segments that each cell contains, only a fraction is used at any given time, and those genes that are seldomly used are packaged much tightly as compared to the ones that are 'expressed' or used during the lifetime of a cell. (sglabepigenetics.com)
  • Trial organizers announced that the first participant had been treated using immune cells with four base-edited genes, equipping the cells to better target and destroy tumors. (cdc.gov)
  • In 1924, Hans Spemann and Hilde Mangold discovered a region in the dorsal blastopore lip of an amphibian embryo that induced certain neighboring cells into becoming neural tissue. (wikipedia.org)
  • As an embryo develops, a single fertilized cell progresses through multiple rounds of cell division. (asu.edu)
  • In order to break the initial "egg shape" of the embryo, cells need to polarize in a precise and coordinated manner. (nature.com)
  • An organizer population has been identified in the anterior end of the primitive streak of the mid-streak stage embryo, by the expression of Hnf3β , Gsc lacZ and Chrd , and the ability of these cells to induce a second neural axis in the host embryo. (silverchair.com)
  • However, though BC is emerging as a potential organ transplant option, challenges regarding organ size scalability, immune system incompatibilities, long-term maintenance, potential evolutionary distance, or unveiled mechanisms between donor and host cells remain. (frontiersin.org)
  • Better understanding of mechanisms that promote neural stem cell recruitment and differentiation are important factors to create successful stem cell therapy. (yale.edu)
  • This center predisposes cells in the blastula stage to become neural tissue. (wikipedia.org)
  • The process of gastrulation is linked to determination of mesodermal cell fates, such that patterning of tissue fates and patterning of cell behavior are interconnected. (nature.com)
  • Autofluorescence imaging permits label-free cell type identification in live airway tissue and reveals the dynamic formation of airway secretory cell associated antigen passages. (elifesciences.org)
  • Using a WNT-activating gradient, we generated a neural tissue exhibiting progressive caudalization from forebrain to midbrain to hindbrain, including formation of isthmic organizer characteristics. (nature.com)
  • Fig. 1: Design of the MiSTR cell culture system and establishment of a WNT signaling gradient in hESC-derived tissue. (nature.com)
  • In the laboratory model called MiSTR (Microfluidic-controlled Stem cell Regionalisation), we can create tissue that contains different brain regions next to each other, similar to an embryonic brain approximately four to five weeks after fertilisation. (neurosciencenews.com)
  • Understanding the signaling clues and soluble factors that promote neural stem cell migration can provide insight for tissue engineers and neurologists to create a therapy which can enhance cellular response to brain tissue damage. (yale.edu)
  • Harvard's ability is critical in this case, Summers said, given the promise of stem cells to cure organ or tissue failure from diseases that afflict 150 million nationally. (harvard.edu)
  • Stem cells have generated excitement among researchers from their ability to both regenerate themselves and to produce specialized tissue cells. (harvard.edu)
  • In the case of neural cells, protein aggregates are associated with neurodegenerative disorders such as Alzheimer's, Huntington's, and Parkinson's disease. (genengnews.com)
  • In order to develop stem cell treatments for neurological diseases such as Parkinson's Disease, epilepsy and stroke, researchers must first understand how the human brain develops in the embryonic stage. (neurosciencenews.com)
  • It took us ten years to develop a stem cell treatment for Parkinson's disease because our methods were dependent on trial and error. (neurosciencenews.com)
  • We show that a Gbx2 -positive, Otx2 -/ Hoxa2 -negative territory corresponding to rhombomere 1 forms prior to an identifiable isthmic organiser. (biomedcentral.com)
  • Early global overexpression of Hoxa2 at embryonic day 0 has no effect on the expression of isthmic signalling molecules or the allocation of rhombomere 1 territory, but selectively results in the loss of granule cell markers at embryonic day 6 and the depletion of cell bodies from the external granule cell layer. (biomedcentral.com)
  • By contrast, a subset of coextensive nuclei is refractory to ectopic Hoxa2 and is presumably induced solely by isthmic organiser activity. (biomedcentral.com)
  • The early designation of an Otx2 -negative, Hoxa2 -negative region, prior to the appearance of the isthmic organiser, is a key initial step in the specification of the cerebellum. (biomedcentral.com)
  • builds a bridge to today's molecular and cellular understanding self-organization in developing systems, including gastrulation, stem cell organoids, morphogen gradients, invertebrate systems, Evo-Devo, and emerging fields deriving from the discovery of embryonic induction. (elsevier.com)
  • Develop a biological knowledge base common to contemporary biologists, encompassing microscopy, cell structure, cellular membranes, and nucleic acids biology. (uaeu.ac.ae)
  • The pocket protein family controls several cellular functions such as cell cycle, differentiation, and apoptosis, among others. (ehu.eus)
  • This process in turn determines what tissues the adjacent cells will form. (wikipedia.org)
  • Ectoderm is one of three germ layers-groups of cells that coalesce early during the embryonic life of all animals except maybe sponges, and from which organs and tissues form. (asu.edu)
  • Fig. 3: Single-cell transcriptomics of dorsal and ventral MiSTR tissues. (nature.com)
  • Here, we uncovered a mechanism of progenitor cell allocation that stems from an incomplete process of epithelial delamination that allows progenitors to coordinate their movement with adjacent extra-embryonic tissues. (elifesciences.org)
  • APCDD1 inhibits BMP signaling in cells and tissues. (xenbase.org)
  • Rhombic lip derivatives, normally destined to occupy the external granule cell layer, violate the cerebellar boundary to form a ventrolateral nucleus in a position comparable to that occupied by rhombic lip derived neurons in rhombomere 2. (biomedcentral.com)
  • This is one of the early divergent phyla at the base of eumetazoan phylogenetic tree and share eumetazoan properties like defined body axis, distinct germ layers and cell types such as neurons, epithelio-muscular cells etc. (sglabepigenetics.com)
  • Harvard President Lawrence H. Summers said Harvard is one of the few institutions that have the ability to step into the gap left by the federal government's decision to ban federal funding of research on human embryonic stem cell lines created after Aug. 9, 2001. (harvard.edu)
  • The morphogenetic movements of gastrulation rearrange the three germ layers precursors, positioning mesodermal cells between outer ectodermal and inner endodermal cells to shape the head-to-tail body axis. (nature.com)
  • Finally, we characterize embryonic-stage CHD in Foxj1 loss-of-function mice, demonstrating randomized heart looping. (bvsalud.org)
  • Gastrulation is a key event in animal embryogenesis during which germ layer precursors are rearranged and the embryonic axes are established. (nature.com)
  • At 10 hpf, the germ ring and the embryonic shield were formed, indicating the stage of early gastrula. (bioone.org)
  • Basal cell carcinoma (BCC) is a nonmelanocytic skin cancer (ie, an epithelial tumor) that arises from basal cells (ie, small, round cells found in the lower layer of the epidermis). (medscape.com)
  • Progenitors of the zebrafish laterality organ originate from the superficial epithelial enveloping layer by an apical constriction process of cell delamination. (elifesciences.org)
  • A developmental signaling center is defined as a group of cells that release various morphogens which can determine the fates, or destined cell types, of adjacent cells. (wikipedia.org)
  • To take human organ generation via BC and transplantation to the next step, we reviewed current emerging organ generation technologies and the associated efficiency of chimera formation in human cells from the standpoint of developmental biology. (frontiersin.org)
  • With knowledge of how neural cells are formed at different developmental stages, researchers have the opportunity to develop new stem cell therapies more quickly in the laboratory. (neurosciencenews.com)
  • Pattern formation in multicellular systems depends on short range interactions between distinctly specified cells. (biologists.com)
  • In living systems actin regulates fundamental processes such as cell division, migration, membrane protrusions, intracellular interactions, and force generation. (yale.edu)
  • The remaining delaminated cells follow the movement of apically attached progenitors by a protrusion-dependent cell-cell contact mechanism, avoiding sequestration by the adjacent endoderm, ensuring their collective fate and allocation at the site of differentiation. (elifesciences.org)
  • Transcription factor complexes have varied effects on cell fate and behavior, but how this diversification of function occurs is largely unknown. (xenbase.org)
  • The algae penetrate and cohabit inside the embryonic membranes and cells of developing amphibians. (yale.edu)
  • The major theme will be devoted to describe and analyze the molecules of life, light microscopy, fine cell structure and function, cell membranes structure and function, cell division and staining procedures. (uaeu.ac.ae)
  • Abstract title:Stem cells from the mammalian blastocyst-How similar are mouse and human? (csh-asia.org)
  • Involution follows bottle cell contraction and spreads laterally and ventrally leading to the formation of the blastopore, a ring of involuting cells that encircles the yolky vegetal endoderm cells. (nature.com)
  • ventral pancreatic precursor 1 ( vpp1 ) is a marker gene that is differentially expressed in a cell population within the dorsal endoderm in a pattern partially overlapping with that of hematopoietically expressed homeobox ( hhex ) during gastrulation. (xenbase.org)
  • L) Statistic analysis of phospho- histone H3-positive cells on the whole surface of bisected vegetal endoderm , as demarcated by the red dashed lines in J and K. As the distribution of phospho-histone H3-positive cells across the whole vegetal endoderm sur - face did not show obvious bias, for simplicity, we counted the whole area rather than only putative vpp1 -positive area. (xenbase.org)
  • The head organizer is located in the anterior visceral endoderm (AVE) and the trunk organizer in the node and anterior primitive streak. (nih.gov)
  • Ectopic expression of a critical dose of hhex led to a greatly enlarged vpp1 -positive domain and, subsequently, to the formation of giant ventral pancreata, putatively by conversion of intestinal to ventral pancreatic precursor cells. (xenbase.org)
  • We report here that Serrate and Notch mediate the interaction between dorsal and ventral cells to direct localized expression of Wingless at the D/V boundary. (biologists.com)
  • Cells are assigned their compartment-specific identity through localized expression of transcription factors (reviewed by Lawrence and Morata, 1994 ). (biologists.com)
  • Pan and Rubin, 1995 ), and leads to localized expression of the secreted signaling molecule Decapentaplegic (Dpp) in anterior cells near the compartment boundary of the wing disc. (biologists.com)
  • This process requires a signal between dorsal and ventral cells which leads to localized expression of a signaling molecule at the compart-ment boundary. (biologists.com)
  • We found that this period difference between species stems from slower biochemical reactions in human cells, including slower protein degradation and longer delays in gene expression processes. (irbbarcelona.org)
  • Cerebellar granule cell precursors are specifically generated within the hindbrain segment, rhombomere 1, which is bounded rostrally by the midbrain/hindbrain isthmus and caudally by the boundary of the Hoxa2 expression domain. (biomedcentral.com)
  • of cell viability cytomorphology nitric oxide metabolic activity matrix composition gene proteomics and expression. (bioinbrief.com)
  • however, its expression varies drastically from cell type to cell type. (sglabepigenetics.com)
  • Maternal expression at 8 ​cell stage (A, B) is localized in the animal pole and is frequently unevenly distributed. (xenbase.org)
  • Genomic alteration using adenine base editors demonstrated the most potency in restarting fetal hemoglobin expression in cells of patients with sickle cell disease, study results showed. (cdc.gov)
  • Scientists at St. Jude Children's Research Hospital and the Broad Institute of MIT and Harvard used a next-generation genome editing technology, adenosine base editing, to restart fetal hemoglobin expression in SCD patient cells. (cdc.gov)
  • The approach raised the expression of fetal hemoglobin to higher, more stable, and more uniform levels than other genome editing technologies that use CRISPR/Cas9 nuclease in human hematopoietic stem cells. (cdc.gov)
  • Using global chromatin organizer and master regulator SATB1 as a paradigm Dr Galande's laboratory set out to address the fundamental question of how such compartmentalization of gene activity is coordinated. (sglabepigenetics.com)
  • Recent reports from our laboratory and other groups have demonstrated that SATB1 is known to play an important role in the regulation of Interleukin 5 (IL-5) gene locus in peripheral CD4+ T-cells and thereby regulate T-helper 2 (TH2) differentiation. (sglabepigenetics.com)
  • Data from two pivotal trials suggest that a single infusion of the CRISPR-based gene therapy exagamglogene autotemcel (exa-cel) can provide a 'functional cure' for patients with transfusion-dependent beta-thalassemia or severe sickle cell disease. (cdc.gov)
  • Novavax to Use Vivalis' Duck Embryonic Stem Cell Line for Vaccine. (genengnews.com)
  • The US Senate has once again passed a bill to allow federal dollars to fund embryonic stem cell research. (fsrn.org)
  • Stem Cell Rep. 3 , 987-999 (2014). (nature.com)
  • Stem cell researchers at Lund University in Sweden have developed a new research model of the early embryonic brain. (neurosciencenews.com)
  • This is a significant step forward for stem cell research. (neurosciencenews.com)
  • On the Democratic side, all the candidates are pro-abortion, pro-embryonic stem cell research, and, with a single exception, against the federal ban on partial-birth abortion. (theinterim.com)
  • Former New York City mayor Rudy Giuliani, the one-time frontrunner, supports abortion, embryonic stem cell research (with limitations) and same-sex "marriage. (theinterim.com)
  • Unfortunately, he supports federal funding of embryonic stem cell research and was instrumental in enacting campaign finance reform, a law that hurts the ability of advocacy groups, including pro-lifers, to disseminate information during election campaigns. (theinterim.com)
  • The Harvard Stem Cell Institute's inaugural symposium kicked off in interdisciplinary fashion Friday (April 23) with discussions that explored the business, ethics, and science of stem cell research. (harvard.edu)
  • Melton and the institute's other co-director, Professor of Medicine David Scadden, who is also director of Massachusetts General Hospital's Center for Regenerative Medicine and Technology, outlined the basics of stem cell research for the audience. (harvard.edu)
  • The institute plans to draw on expertise across the University to explore the science, politics, ethics, business, and other issues of stem cell research. (harvard.edu)
  • The daylong event included talks about the ethics of stem cell research, the future business possibilities stemming from the work, and descriptions of the cutting-edge science being performed on stem cells today. (harvard.edu)
  • Professor of Government Michael Sandel (left) speaks about 'The Ethics of Stem Cell Research. (harvard.edu)
  • David Scadden (below), co-director of the Stem Cell Institute, who also spoke at the symposium, chats with some conference attendees during a break. (harvard.edu)
  • Institute planners expect to host a major symposium annually similar to Friday's as a way to stimulate the exchange of ideas and foster a sense of community among stem cell researchers at Harvard. (harvard.edu)
  • Co-Director of the Stem Cell Institute Douglas Melton, who also spoke at the symposium, listens intently during a talk. (harvard.edu)
  • second type of cell, the human embryonic stem cell. (harvard.edu)
  • Charlie Bass is taking serious heat from social conservatives for his leading role in the House vote to relax federal restrictions on stem cell research using new embryonic cell lines. (nhbr.com)
  • Moreover, the various hierarchical levels of higher-order chromatin assembly are interconvertible depending upon the physiological status of the cells. (sglabepigenetics.com)
  • A comparable process of short range interaction between dorsal and ventral cells leads to formation of a growth control center at the D/V compartment boundary. (biologists.com)
  • Single-cell transcriptomics revealed that rostro-caudal organization was already established at 24 h of differentiation, and that the first markers of a neural-specific transcription program emerged in the rostral cells at 48 h. (nature.com)
  • Basal cell carcinoma of the right lower lid. (medscape.com)
  • Given that basal cell carcinoma rarely metastasizes, laboratory and imaging studies are not commonly clinically indicated in patients presenting with localized lesions. (medscape.com)
  • A skin biopsy is often required to confirm the diagnosis and determine the histologic subtype of basal cell carcinoma (BCC). (medscape.com)
  • Nodular basal cell carcinoma. (medscape.com)
  • Melanin is also present within the tumor and in the surrounding stroma, as seen in pigmented basal cell carcinoma. (medscape.com)
  • A-B. The activation of BMP and Wnt pathways was measured at single-cell level, using NIH 3T3 mouse fibroblast cells cultured in the presence of BMP and Wnt ligands. (xenbase.org)
  • With this new insight, researchers hope to be able to produce different types of neural cells for the treatment of neurological diseases more efficiently. (neurosciencenews.com)
  • The challenge is that there are thousands of different sub-types of neural cells in the human brain, and for each disease we need to be able to produce exactly the right type of neural cell", says Agnete Kirkeby, researcher at the Wallenberg Centre for Molecular Medicine and the Department of Experimental Medical Science at Lund University. (neurosciencenews.com)
  • Once we have the map we will also become better at producing human neural cells in the laboratory that could be used for transplantations, regenerative therapy and to study the brain's function as well as different disease states. (neurosciencenews.com)
  • Hydra exhibits morphallactic regeneration i.e. regaining missing body parts without involving cell proliferation. (sglabepigenetics.com)