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.
Proteins obtained from the ZEBRAFISH. Many of the proteins in this species have been the subject of studies involving basic embryological development (EMBRYOLOGY).
The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.
ANIMALS whose GENOME has been altered by GENETIC ENGINEERING, or their offspring.
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.
Synthetic analogs of NUCLEIC ACIDS composed of morpholine ring derivatives (MORPHOLINES) linked by phosphorodimidates. One standard DNA nucleic acid base (ADENINE; GUANINE; CYTOSINE; OR THYMINE) is bound to each morpholine ring.
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 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.
Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.
Membranous appendage of fish and other aquatic organisms used for locomotion or balance.
Aquatic vertebrate sensory system in fish and amphibians. It is composed of sense organs (canal organs and pit organs) containing neuromasts (MECHANORECEPTORS) that detect water displacement caused by moving objects.
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.
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.
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).
Morphological and physiological development of EMBRYOS.
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 artificial induction of GENE SILENCING by the use of RNA INTERFERENCE to reduce the expression of a specific gene. It includes the use of DOUBLE-STRANDED RNA, such as SMALL INTERFERING RNA and RNA containing HAIRPIN LOOP SEQUENCE, and ANTI-SENSE OLIGONUCLEOTIDES.
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.
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.
Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.
Short fragments of DNA or RNA that are used to alter the function of target RNAs or DNAs to which they hybridize.
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.
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).
A process of complicated morphogenetic cell movements that reorganizes a bilayer embryo into one with three GERM LAYERS and specific orientation (dorsal/ventral; anterior/posterior). Gastrulation describes the germ layer development of a non-mammalian BLASTULA or that of a mammalian BLASTOCYST.
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.
The relationships of groups of organisms as reflected by their genetic makeup.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
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 sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
A region, of SOMITE development period, that contains a number of paired arches, each with a mesodermal core lined by ectoderm and endoderm on the two sides. In lower aquatic vertebrates, branchial arches develop into GILLS. In higher vertebrates, the arches forms outpouchings and develop into structures of the head and neck. Separating the arches are the branchial clefts or grooves.
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.
Formation of differentiated cells and complicated tissue organization to provide specialized functions.
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.
Non-human animals, selected because of specific characteristics, for use in experimental research, teaching, or testing.
The middle germ layer of an embryo derived from three paired mesenchymal aggregates along the neural tube.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Chromatophores (large pigment cells of fish, amphibia, reptiles and many invertebrates) which contain melanin. Short term color changes are brought about by an active redistribution of the melanophores pigment containing organelles (MELANOSOMES). Mammals do not have melanophores; however they have retained smaller pigment cells known as MELANOCYTES.
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.
A genus of pufferfish commonly used for research.
The paired caudal parts of the PROSENCEPHALON from which the THALAMUS; HYPOTHALAMUS; EPITHALAMUS; and SUBTHALAMUS are derived.
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 primordial kidney that develops from the INTERMEDIATE MESODERM in the embryos of vertebrates, and is succeeded by the MESONEPHROS. In higher vertebrates and humans, the pronephros is a vestigial and transient structure.
The two longitudinal ridges along the PRIMITIVE STREAK appearing near the end of GASTRULATION during development of nervous system (NEURULATION). The ridges are formed by folding of NEURAL PLATE. Between the ridges is a neural groove which deepens as the fold become elevated. When the folds meet at midline, the groove becomes a closed tube, the NEURAL TUBE.
The physiological renewal, repair, or replacement of tissue.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
The only genus in the family Oryziinae, order BELONIFORMES. Oryzias are egg-layers; other fish of the same order are livebearers. Oryzias are used extensively in testing carcinogens.
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.
A large family of structurally-related transcription factors that were originally discovered based upon their close sequence homology to an HMG-box domain found in SEX-DETERMINING REGION Y PROTEIN. Many SOX transcription factors play important roles in regulating CELL DIFFERENTIATION. The numerous members of this family are organized in several subgroups according to structural identities found within the proteins.
An activity in which the body is propelled through water by specific movement of the arms and/or the legs. Swimming as propulsion through water by the movement of limbs, tail, or fins of animals is often studied as a form of PHYSICAL EXERTION or endurance.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.
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)
Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.
Thin-walled sacs or spaces which function as a part of the respiratory system in birds, fishes, insects, and mammals.
Short fragments of DNA that are used to alter the function of target RNAs or DNAs to which they hybridize.
Used in the form of its salts as a dye and as an intermediate in manufacture of Acid Yellow, diazo dyes, and indulines.
A paired box transcription factor that is essential for ORGANOGENESIS of the CENTRAL NERVOUS SYSTEM and KIDNEY.
A sequence of amino acids in a polypeptide or of nucleotides in DNA or RNA that is similar across multiple species. A known set of conserved sequences is represented by a CONSENSUS SEQUENCE. AMINO ACID MOTIFS are often composed of conserved sequences.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
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.
A family of conserved cell surface receptors that contain EPIDERMAL GROWTH FACTOR repeats in their extracellular domain and ANKYRIN repeats in their cytoplasmic domains. The cytoplasmic domain of notch receptors is released upon ligand binding and translocates to the CELL NUCLEUS where it acts as transcription factor.
The inner of the three germ layers of an embryo.
Animals having a vertebral column, members of the phylum Chordata, subphylum Craniata comprising mammals, birds, reptiles, amphibians, and fishes.
The organ of sight constituting a pair of globular organs made up of a three-layered roughly spherical structure specialized for receiving and responding to light.
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.
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.
A fibroblast growth factor that is expressed primarily during development.
Proteins obtained from species of fish (FISHES).
The essential part of the hearing organ consists of two labyrinthine compartments: the bony labyrinthine and the membranous labyrinth. The bony labyrinth is a complex of three interconnecting cavities or spaces (COCHLEA; VESTIBULAR LABYRINTH; and SEMICIRCULAR CANALS) in the TEMPORAL BONE. Within the bony labyrinth lies the membranous labyrinth which is a complex of sacs and tubules (COCHLEAR DUCT; SACCULE AND UTRICLE; and SEMICIRCULAR DUCTS) forming a continuous space enclosed by EPITHELIUM and connective tissue. These spaces are filled with LABYRINTHINE FLUIDS of various compositions.
A small order of primarily marine fish containing 340 species. Most have a rotund or box-like shape. TETRODOTOXIN is found in their liver and ovaries.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
Alkaloids with powerful hypotensive effects isolated from American or European Hellebore (Veratrum viride Ait. Liliaceae and Veratrum album L. Liliaceae). They increase cholinergic and decrease adrenergic tone with appropriate side effects and at higher doses depress respiration and produce cardiac arrhythmias; only the ester alkaloids have been used as hypotensive agents in specific instances. They have been generally replaced by drugs with fewer adverse effects.
A family of DNA-binding transcription factors that contain a basic HELIX-LOOP-HELIX MOTIF.
A growth differentiation factor that plays a role in the neural differentiation, specifically in the retinal development of the EYE.
The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.
The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.
Congenital absence of or defects in structures of the jaw.
The developmental history of specific differentiated cell types as traced back to the original STEM CELLS in the embryo.
'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 genetic complement of an organism, including all of its GENES, as represented in its DNA, or in some cases, its RNA.
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.
Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.
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).
Genes that are introduced into an organism using GENE TRANSFER TECHNIQUES.
The hollow, muscular organ that maintains the circulation of the blood.
A method for ordering genetic loci along CHROMOSOMES. The method involves fusing irradiated donor cells with host cells from another species. Following cell fusion, fragments of DNA from the irradiated cells become integrated into the chromosomes of the host cells. Molecular probing of DNA obtained from the fused cells is used to determine if two or more genetic loci are located within the same fragment of donor cell DNA.
The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.
Any of the tubular vessels conveying the blood (arteries, arterioles, capillaries, venules, and veins).
Paired respiratory organs of fishes and some amphibians that are analogous to lungs. They are richly supplied with blood vessels by which oxygen and carbon dioxide are exchanged directly with the environment.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.
Populations of thin, motile processes found covering the surface of ciliates (CILIOPHORA) or the free surface of the cells making up ciliated EPITHELIUM. Each cilium arises from a basic granule in the superficial layer of CYTOPLASM. The movement of cilia propels ciliates through the liquid in which they live. The movement of cilia on a ciliated epithelium serves to propel a surface layer of mucus or fluid. (King & Stansfield, A Dictionary of Genetics, 4th ed)
The observable response an animal makes to any situation.
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.

FGF8 induces formation of an ectopic isthmic organizer and isthmocerebellar development via a repressive effect on Otx2 expression. (1/4712)

Beads containing recombinant FGF8 (FGF8-beads) were implanted in the prospective caudal diencephalon or midbrain of chick embryos at stages 9-12. This induced the neuroepithelium rostral and caudal to the FGF8-bead to form two ectopic, mirror-image midbrains. Furthermore, cells in direct contact with the bead formed an outgrowth that protruded laterally from the neural tube. Tissue within such lateral outgrowths developed proximally into isthmic nuclei and distally into a cerebellum-like structure. These morphogenetic effects were apparently due to FGF8-mediated changes in gene expression in the vicinity of the bead, including a repressive effect on Otx2 and an inductive effect on En1, Fgf8 and Wnt1 expression. The ectopic Fgf8 and Wnt1 expression domains formed nearly complete concentric rings around the FGF8-bead, with the Wnt1 ring outermost. These observations suggest that FGF8 induces the formation of a ring-like ectopic signaling center (organizer) in the lateral wall of the brain, similar to the one that normally encircles the neural tube at the isthmic constriction, which is located at the boundary between the prospective midbrain and hindbrain. This ectopic isthmic organizer apparently sends long-range patterning signals both rostrally and caudally, resulting in the development of the two ectopic midbrains. Interestingly, our data suggest that these inductive signals spread readily in a caudal direction, but are inhibited from spreading rostrally across diencephalic neuromere boundaries. These results provide insights into the mechanism by which FGF8 induces an ectopic organizer and suggest that a negative feedback loop between Fgf8 and Otx2 plays a key role in patterning the midbrain and anterior hindbrain.  (+info)

The homeobox gene Pitx2: mediator of asymmetric left-right signaling in vertebrate heart and gut looping. (2/4712)

Left-right asymmetry in vertebrates is controlled by activities emanating from the left lateral plate. How these signals get transmitted to the forming organs is not known. A candidate mediator in mouse, frog and zebrafish embryos is the homeobox gene Pitx2. It is asymmetrically expressed in the left lateral plate mesoderm, tubular heart and early gut tube. Localized Pitx2 expression continues when these organs undergo asymmetric looping morphogenesis. Ectopic expression of Xnr1 in the right lateral plate induces Pitx2 transcription in Xenopus. Misexpression of Pitx2 affects situs and morphology of organs. These experiments suggest a role for Pitx2 in promoting looping of the linear heart and gut.  (+info)

A Drosophila doublesex-related gene, terra, is involved in somitogenesis in vertebrates. (3/4712)

The Drosophila doublesex (dsx) gene encodes a transcription factor that mediates sex determination. We describe the characterization of a novel zebrafish zinc-finger gene, terra, which contains a DNA binding domain similar to that of the Drosophila dsx gene. However, unlike dsx, terra is transiently expressed in the presomitic mesoderm and newly formed somites. Expression of terra in presomitic mesoderm is restricted to cells that lack expression of MyoD. In vivo, terra expression is reduced by hedgehog but enhanced by BMP signals. Overexpression of terra induces rapid apoptosis both in vitro and in vivo, suggesting that a tight regulation of terra expression is required during embryogenesis. Terra has both human and mouse homologs and is specifically expressed in mouse somites. Taken together, our findings suggest that terra is a highly conserved protein that plays specific roles in early somitogenesis of vertebrates.  (+info)

Alzheimer's disease: clues from flies and worms. (4/4712)

Presenilin mutations give rise to familial Alzheimer's disease and result in elevated production of amyloid beta peptide. Recent evidence that presenilins act in developmental signalling pathways may be the key to understanding how senile plaques, neurofibrillary tangles and apoptosis are all biochemically linked.  (+info)

Isolation of zebrafish gdf7 and comparative genetic mapping of genes belonging to the growth/differentiation factor 5, 6, 7 subgroup of the TGF-beta superfamily. (5/4712)

The Growth/differentiation factor (Gdf) 5, 6, 7 genes form a closely related subgroup belonging to the TGF-beta superfamily. In zebrafish, there are three genes that belong to the Gdf5, 6, 7 subgroup that have been named radar, dynamo, and contact. The genes radar and dynamo both encode proteins most similar to mouse GDF6. The orthologous identity of these genes on the basis of amino acid similarities has not been clear. We have identified gdf7, a fourth zebrafish gene belonging to the Gdf5, 6, 7 subgroup. To assign correct orthologies and to investigate the evolutionary relationships of the human, mouse, and zebrafish Gdf5, 6, 7 subgroup, we have compared genetic map positions of the zebrafish and mammalian genes. We have mapped zebrafish gdf7 to linkage group (LG) 17, contact to LG9, GDF6 to human chromosome (Hsa) 8 and GDF7 to Hsa2p. The radar and dynamo genes have been localized previously to LG16 and LG19, respectively. A comparison of syntenies shared among human, mouse, and zebrafish genomes indicates that gdf7 is the ortholog of mammalian GDF7/Gdf7. LG16 shares syntenic relationships with mouse chromosome (Mmu) 4, including Gdf6. Portions of LG16 and LG19 appear to be duplicate chromosomes, thus suggesting that radar and dynamo are both orthologs of Gdf6. Finally, the mapping data is consistent with contact being the zebrafish ortholog of mammalian GDF5/Gdf5.  (+info)

A molecular pathway revealing a genetic basis for human cardiac and craniofacial defects. (6/4712)

Microdeletions of chromosome 22q11 are the most common genetic defects associated with cardiac and craniofacial anomalies in humans. A screen for mouse genes dependent on dHAND, a transcription factor implicated in neural crest development, identified Ufd1, which maps to human 22q11 and encodes a protein involved in degradation of ubiquitinated proteins. Mouse Ufd1 was specifically expressed in most tissues affected in patients with 22q11 deletion syndrome. The human UFD1L gene was deleted in all 182 patients studied with 22q11 deletion, and a smaller deletion of approximately 20 kilobases that removed exons 1 to 3 of UFD1L was found in one individual with features typical of 22q11 deletion syndrome. These data suggest that UFD1L haploinsufficiency contributes to the congenital heart and craniofacial defects seen in 22q11 deletion.  (+info)

Expression of CD44 in Apc and Tcf mutant mice implies regulation by the WNT pathway. (7/4712)

Overexpression of cell surface glycoproteins of the CD44 family is an early event in the colorectal adenoma-carcinoma sequence. This suggests a link with disruption of APC tumor suppressor protein-mediated regulation of beta-catenin/Tcf-4 signaling, which is crucial in initiating tumorigenesis. To explore this hypothesis, we analyzed CD44 expression in the intestinal mucosa of mice and humans with genetic defects in either APC or Tcf-4, leading to constitutive activation or blockade of the beta-catenin/Tcf-4 pathway, respectively. We show that CD44 expression in the non-neoplastic intestinal mucosa of Apc mutant mice is confined to the crypt epithelium but that CD44 is strongly overexpressed in adenomas as well as in invasive carcinomas. This overexpression includes the standard part of the CD44 (CD44s) as well as variant exons (CD44v). Interestingly, deregulated CD44 expression is already present in aberrant crypt foci with dysplasia (ACFs), the earliest detectable lesions of colorectal neoplasia. Like ACFs of Apc-mutant mice, ACFs of familial adenomatous polyposis (FAP) patients also overexpress CD44. In sharp contrast, Tcf-4 mutant mice show a complete absence of CD44 in the epithelium of the small intestine. This loss of CD44 concurs with loss of stem cell characteristics, shared with adenoma cells. Our results indicate that CD44 expression is part of a genetic program controlled by the beta-catenin/Tcf-4 signaling pathway and suggest a role for CD44 in the generation and turnover of epithelial cells.  (+info)

Comparative synteny cloning of zebrafish you-too: mutations in the Hedgehog target gli2 affect ventral forebrain patterning. (8/4712)

Zebrafish you-too (yot) mutations interfere with Hedgehog (Hh) signaling during embryogenesis. Using a comparative synteny approach, we isolated yot as a zinc finger transcription factor homologous to the Hh target gli2. Two alleles of yot contain nonsense mutations resulting in carboxy-terminally truncated proteins. In addition to causing defects in midline development, muscle differentiation, and retinal axon guidance, yot mutations disrupt anterior pituitary and ventral forebrain differentiation. yot mutations also cause ectopic lens formation in the ventral diencephalon. These findings reveal that truncated zebrafish Gli2 proteins interfere with Hh signaling necessary for differentiation and axon guidance in the ventral forebrain.  (+info)

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.

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.

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.

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.

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.

Morpholinos are synthetic oligonucleotides that contain morpholine rings in their backbone instead of the ribose or deoxyribose sugars found in DNA and RNA. They are often used as antisense agents to inhibit gene expression by binding to complementary RNA sequences, preventing translation or splicing. Morpholinos are resistant to nucleases and have a neutral charge, which makes them more stable and less likely to cause off-target effects compared to other antisense technologies. They have been widely used in research to study gene function and have also shown promise as therapeutic agents for various diseases, including neuromuscular disorders and viral infections.

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.

"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.

A larva is a distinct stage in the life cycle of various insects, mites, and other arthropods during which they undergo significant metamorphosis before becoming adults. In a medical context, larvae are known for their role in certain parasitic infections. Specifically, some helminth (parasitic worm) species use larval forms to infect human hosts. These invasions may lead to conditions such as cutaneous larva migrans, visceral larva migrans, or gnathostomiasis, depending on the specific parasite involved and the location of the infection within the body.

The larval stage is characterized by its markedly different morphology and behavior compared to the adult form. Larvae often have a distinct appearance, featuring unsegmented bodies, simple sense organs, and undeveloped digestive systems. They are typically adapted for a specific mode of life, such as free-living or parasitic existence, and rely on external sources of nutrition for their development.

In the context of helminth infections, larvae may be transmitted to humans through various routes, including ingestion of contaminated food or water, direct skin contact with infective stages, or transmission via an intermediate host (such as a vector). Once inside the human body, these parasitic larvae can cause tissue damage and provoke immune responses, leading to the clinical manifestations of disease.

It is essential to distinguish between the medical definition of 'larva' and its broader usage in biology and zoology. In those fields, 'larva' refers to any juvenile form that undergoes metamorphosis before reaching adulthood, regardless of whether it is parasitic or not.

I could not find a medical definition for "animal fins" as a single concept. However, in the field of comparative anatomy and evolutionary biology, fins are specialized limbs that some aquatic animals use for movement, stability, or sensory purposes. Fins can be found in various forms among different animal groups, including fish, amphibians, reptiles, and even mammals like whales and dolphins.

Fins consist of either bony or cartilaginous structures that support webs of skin or connective tissue. They may contain muscles, blood vessels, nerves, and sensory organs, which help animals navigate their underwater environment efficiently. The specific structure and function of fins can vary greatly depending on the animal's taxonomic group and lifestyle adaptations.

In a medical context, studying animal fins could provide insights into the evolution of limbs in vertebrates or contribute to the development of biomimetic technologies inspired by nature. However, there is no standalone medical definition for 'animal fins.'

The lateral line system is a sensory organ found in aquatic animals, such as fish and some aquatic amphibians. It is a series of fluid-filled canals and sensory cells that run along the sides of the body, head, and fins. These sensory cells are called neuromasts and contain hair cells that respond to vibrations and water movements. The lateral line system helps these animals detect movement, pressure changes, and vibrations in their aquatic environment, which aids in schooling behavior, prey detection, and avoiding predators.

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.

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.

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.

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.

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.

Gene knockdown techniques are methods used to reduce the expression or function of specific genes in order to study their role in biological processes. These techniques typically involve the use of small RNA molecules, such as siRNAs (small interfering RNAs) or shRNAs (short hairpin RNAs), which bind to and promote the degradation of complementary mRNA transcripts. This results in a decrease in the production of the protein encoded by the targeted gene.

Gene knockdown techniques are often used as an alternative to traditional gene knockout methods, which involve completely removing or disrupting the function of a gene. Knockdown techniques allow for more subtle and reversible manipulation of gene expression, making them useful for studying genes that are essential for cell survival or have redundant functions.

These techniques are widely used in molecular biology research to investigate gene function, genetic interactions, and disease mechanisms. However, it is important to note that gene knockdown can have off-target effects and may not completely eliminate the expression of the targeted gene, so results should be interpreted with caution.

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.

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.

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

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

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

Antisense oligonucleotides (ASOs) are short synthetic single stranded DNA-like molecules that are designed to complementarily bind to a specific RNA sequence through base-pairing, with the goal of preventing the translation of the target RNA into protein or promoting its degradation.

The antisense oligonucleotides work by hybridizing to the targeted messenger RNA (mRNA) molecule and inducing RNase H-mediated degradation, sterically blocking ribosomal translation, or modulating alternative splicing of the pre-mRNA.

ASOs have shown promise as therapeutic agents for various genetic diseases, viral infections, and cancers by specifically targeting disease-causing genes. However, their clinical application is still facing challenges such as off-target effects, stability, delivery, and potential immunogenicity.

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.

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.

Gastrulation is a fundamental process in embryonic development, characterized by the transformation of a initially flat layer of cells called the blastula into a three-layered structure known as the gastrula. This complex series of cellular movements and rearrangements establishes the foundation for the formation of the three primary germ layers: the ectoderm, mesoderm, and endoderm. These germ layers further differentiate to give rise to all the diverse cell types and tissues in the developing organism, including the nervous system, muscles, bones, and internal organs.

The precise mechanisms of gastrulation vary among different animal groups; however, common features include:

1. Formation of a blastopore: A small indentation or opening that forms on the surface of the blastula, which eventually develops into the primitive gut or anus in the gastrula.
2. Invagination: The process by which cells at the blastopore fold inward and migrate towards the interior of the embryo, forming the endodermal layer.
3. Epiboly: A coordinated movement of cells that spreads over and encloses the yolk within the embryo, contributing to the formation of the ectodermal layer.
4. Delamination: The separation and migration of cells from the epiblast (the outer layer of the blastula) to form the mesodermal layer in between the ectoderm and endoderm.

Gastrulation is a critical period in embryonic development, as errors during this process can lead to severe congenital abnormalities or even embryonic lethality. A thorough understanding of gastrulation has important implications for regenerative medicine, stem cell research, and the study of evolutionary developmental biology (Evo-Devo).

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.

Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.

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.

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.

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.

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.

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.

The branchial region, also known as the pharyngeal region or viscerocranium, is a term used in human anatomy to refer to the area of the developing embryo that gives rise to structures derived from the branchial (or pharyngeal) arches. The branchial arches are a series of paired, rod-like structures that appear early in embryonic development and give rise to various head and neck structures, including the bones and muscles of the face, jaws, and neck, as well as the associated nerves, blood vessels, and connective tissues.

The branchial region is divided into several subregions, each corresponding to a specific branchial arch. The first branchial arch gives rise to structures such as the mandible (lower jaw), maxilla (upper jaw), and muscles of mastication (chewing). The second branchial arch forms the stapes and styloid process in the ear, as well as some neck muscles. The third and fourth branchial arches contribute to the formation of the larynx, thyroid cartilage, and other structures in the neck.

Abnormalities in the development of the branchial region can lead to a variety of congenital defects, such as cleft palate, micrognathia (small jaw), and branchial cysts or sinuses. These conditions may require surgical intervention to correct.

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.

Organogenesis is the process of formation and development of organs during embryonic growth. It involves the complex interactions of cells, tissues, and signaling molecules that lead to the creation of specialized structures in the body. This process begins in the early stages of embryonic development, around week 4-8, and continues until birth. During organogenesis, the three primary germ layers (ectoderm, mesoderm, and endoderm) differentiate into various cell types and organize themselves into specific structures that will eventually form the functional organs of the body. Abnormalities in organogenesis can result in congenital disorders or birth defects.

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.

An animal model in medicine refers to the use of non-human animals in experiments to understand, predict, and test responses and effects of various biological and chemical interactions that may also occur in humans. These models are used when studying complex systems or processes that cannot be easily replicated or studied in human subjects, such as genetic manipulation or exposure to harmful substances. The choice of animal model depends on the specific research question being asked and the similarities between the animal's and human's biological and physiological responses. Examples of commonly used animal models include mice, rats, rabbits, guinea pigs, and non-human primates.

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.

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

Melanophores are specialized pigment-containing cells found in various organisms, including vertebrates and some invertebrates. In humans and other mammals, melanophores are primarily located within the skin's dermal layer and are part of the larger group of chromatophores.

Melanophores contain melanosomes, which are organelles that store and transport the pigment melanin. These cells play a crucial role in determining the coloration of an individual's skin, hair, and eyes by producing, storing, and distributing melanin granules within their cytoplasm.

In response to hormonal signals or neural stimulation, melanophores can undergo changes in the distribution of melanosomes, leading to variations in color intensity. This process is known as melanin dispersion or aggregation and is responsible for various physiological responses, such as skin tanning upon exposure to sunlight or the color-changing abilities observed in some animals like chameleons and cuttlefish.

It's important to note that while humans do not have the ability to change their skin color rapidly like some other animals, melanophores still play a significant role in protecting our skin from harmful ultraviolet radiation by producing melanin, which helps absorb and dissipate this energy, reducing damage to skin cells.

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.

"Takifugu" is not a medical term, but a genus of pufferfish found in the waters of East Asia. However, some people may use it to refer to "pufferfish poisoning," which is a type of food poisoning caused by the consumption of pufferfish that contain a potent neurotoxin called tetrodotoxin. This toxin is found in the fish's organs, such as the liver and ovaries, and can be deadly if ingested in large quantities. Proper preparation and cooking of pufferfish by trained chefs can make it safe to eat, but it is still considered a delicacy with significant risks.

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.

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.

Pronephros is the most primitive type of kidney that develops in the early stages of embryonic development, specifically in the first few weeks of gestation. It is present in many vertebrate animals, including humans, but it is nonfunctional in higher vertesbrates. In humans, pronephros starts to develop around 22 days of gestation and regresses by the end of the fourth week, giving way to the development of the mesonephros, which is the functional kidney at this stage.

Histologically, pronephros consists of a pair of nephrotomes, which are thickened epithelial plates located along the anterior portion of the intermediate mesoderm. Each nephrotome gives rise to a pronephric duct, which extends caudally and eventually forms part of the permanent excretory system. The pronephros also includes a few glomeruli, which are clusters of capillaries that filter waste products from the blood. However, these glomeruli do not function in humans and other higher vertebrates.

Despite its nonfunctional nature in humans, the study of pronephros is important for understanding the developmental processes that give rise to the functional kidney later in gestation. Additionally, studying pronephros in lower vertebrates can provide insights into the evolutionary origins of the kidney and excretory systems in animals.

The neural crest is a transient, multipotent embryonic cell population that originates from the ectoderm (outermost layer) of the developing neural tube (precursor to the central nervous system). These cells undergo an epithelial-to-mesenchymal transition and migrate throughout the embryo, giving rise to a diverse array of cell types and structures.

Neural crest cells differentiate into various tissues, including:

1. Peripheral nervous system (PNS) components: sensory neurons, sympathetic and parasympathetic ganglia, and glial cells (e.g., Schwann cells).
2. Facial bones and cartilage, as well as connective tissue of the skull.
3. Melanocytes, which are pigment-producing cells in the skin.
4. Smooth muscle cells in major blood vessels, heart, gastrointestinal tract, and other organs.
5. Secretory cells in endocrine glands (e.g., chromaffin cells of the adrenal medulla).
6. Parts of the eye, such as the cornea and iris stroma.
7. Dental tissues, including dentin, cementum, and dental pulp.

Due to their wide-ranging contributions to various tissues and organs, neural crest cells play a crucial role in embryonic development and organogenesis. Abnormalities in neural crest cell migration or differentiation can lead to several congenital disorders, such as neurocristopathies.

Regeneration in a medical context refers to the process of renewal, restoration, and growth that replaces damaged or missing cells, tissues, organs, or even whole limbs in some organisms. This complex biological process involves various cellular and molecular mechanisms, such as cell proliferation, differentiation, and migration, which work together to restore the structural and functional integrity of the affected area.

In human medicine, regeneration has attracted significant interest due to its potential therapeutic applications in treating various conditions, including degenerative diseases, trauma, and congenital disorders. Researchers are actively studying the underlying mechanisms of regeneration in various model organisms to develop novel strategies for promoting tissue repair and regeneration in humans.

Examples of regeneration in human medicine include liver regeneration after partial hepatectomy, where the remaining liver lobes can grow back to their original size within weeks, and skin wound healing, where keratinocytes migrate and proliferate to close the wound and restore the epidermal layer. However, the regenerative capacity of humans is limited compared to some other organisms, such as planarians and axolotls, which can regenerate entire body parts or even their central nervous system.

The retina is the innermost, light-sensitive layer of tissue in the eye of many vertebrates and some cephalopods. It receives light that has been focused by the cornea and lens, converts it into neural signals, and sends these to the brain via the optic nerve. The retina contains several types of photoreceptor cells including rods (which handle vision in low light) and cones (which are active in bright light and are capable of color vision).

In medical terms, any pathological changes or diseases affecting the retinal structure and function can lead to visual impairment or blindness. Examples include age-related macular degeneration, diabetic retinopathy, retinal detachment, and retinitis pigmentosa among others.

"Oryzias" is not a medical term, but a genus name in the family Adrianichthyidae, which includes various species of small fish commonly known as "ricefishes" or "medaka." These fish are often used in scientific research, particularly in the fields of genetics and developmental biology. They are not associated with human diseases or medical conditions.

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.

SOX (SRY-related HMG box) transcription factors are a family of proteins that regulate gene expression during embryonic development and in adult tissues. They contain a highly conserved DNA-binding domain, the HMG box, which allows them to bind to specific DNA sequences and influence the transcription of nearby genes. SOX proteins play critical roles in various biological processes such as cell fate determination, differentiation, proliferation, and survival.

SOX transcription factors are classified into several groups (A-H) based on their sequence similarities and functional redundancies. Some well-known members of this family include SOX1, SOX2, SOX3, SOX4, SOX9, SOX10, and SOX17. These proteins often form complexes with other transcription factors or cofactors to modulate their target genes' expression.

Dysregulation of SOX transcription factors has been implicated in several human diseases, including cancer, developmental disorders, and degenerative conditions. For example, SOX2 overexpression is associated with certain types of tumors, while mutations in the SOX9 gene can cause campomelic dysplasia, a severe skeletal disorder.

I'm sorry for any confusion, but "swimming" is not typically considered a medical term. It refers to the act of moving through water using your arms and legs in a rhythmic pattern, often as a form of exercise, recreation, or competition. However, if you're referring to a medical condition related to swimming, such as "swimmer's ear" (otitis externa), I would be happy to provide a definition for that.

Swimmer's ear is a type of outer ear infection caused by water remaining in the ear after swimming or bathing, creating a moist environment that can lead to bacterial growth. It can also be caused by scratching or damaging the lining of the ear canal through the use of cotton swabs or other objects. Symptoms may include itching, redness, pain, and sometimes discharge from the ear. If left untreated, swimmer's ear can lead to more serious complications, such as hearing loss or damage to the inner ear.

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.

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.

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.

Complementary DNA (cDNA) is a type of DNA that is synthesized from a single-stranded RNA molecule through the process of reverse transcription. In this process, the enzyme reverse transcriptase uses an RNA molecule as a template to synthesize a complementary DNA strand. The resulting cDNA is therefore complementary to the original RNA molecule and is a copy of its coding sequence, but it does not contain non-coding regions such as introns that are present in genomic DNA.

Complementary DNA is often used in molecular biology research to study gene expression, protein function, and other genetic phenomena. For example, cDNA can be used to create cDNA libraries, which are collections of cloned cDNA fragments that represent the expressed genes in a particular cell type or tissue. These libraries can then be screened for specific genes or gene products of interest. Additionally, cDNA can be used to produce recombinant proteins in heterologous expression systems, allowing researchers to study the structure and function of proteins that may be difficult to express or purify from their native sources.

Air sacs, also known as alveoli, are tiny air-filled sacs in the lungs where the exchange of oxygen and carbon dioxide occurs during respiration. They are a part of the respiratory system in mammals and birds. In humans, the lungs contain about 300 million alveoli, which are clustered together in small groups called alveolar sacs. The walls of the air sacs are extremely thin, allowing for the easy diffusion of oxygen and carbon dioxide between the air in the sacs and the blood in the capillaries that surround them.

Antisense oligodeoxyribonucleotides (ODNs) are short synthetic single-stranded DNA molecules that are designed to be complementary to a specific RNA sequence. They work by binding to the target mRNA through base-pairing, which prevents the translation of the mRNA into protein, either by blocking the ribosome or inducing degradation of the mRNA. This makes antisense ODNs valuable tools in research and therapeutics for modulating gene expression, particularly in cases where traditional small molecule inhibitors are not effective.

The term "oligodeoxyribonucleotides" refers to short DNA sequences, typically made up of 15-30 nucleotides. These molecules can be chemically modified to improve their stability and binding affinity for the target RNA, which increases their efficacy as antisense agents.

In summary, Antisense oligodeoxyribonucleotides (ODNs) are short synthetic single-stranded DNA molecules that bind to a specific RNA sequence, preventing its translation into protein and thus modulating gene expression.

P-Aminoazobenzene, also known as Aniline Yellow or C.I. 11020, is not typically considered a medical term, but it is a chemical compound with potential health implications. Therefore, I will provide you with its chemical definition and some information related to its toxicological properties.

P-Aminoazobenzene is an organic compound with the molecular formula C6H5NH2-C6H5N=N-. It belongs to the class of aromatic amines and azo dyes, which are known for their potential carcinogenic effects. P-Aminoazobenzene is formed by the diazotization of p-aminophenol followed by coupling with phenol or its derivatives.

In terms of toxicity, p-Aminoazobenzene has been shown to have carcinogenic and mutagenic effects in various animal models. It can cause liver damage and increase the risk of developing liver tumors after prolonged exposure. The compound is also believed to have immunotoxic properties, affecting the immune system's functioning.

However, it is essential to note that p-Aminoazobenzene is not typically used in medical applications or treatments due to its toxicity and potential health hazards. It is primarily used in research settings for studying chemical reactions and understanding the mechanisms of carcinogenesis and mutagenesis.

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.

A conserved sequence in the context of molecular biology refers to a pattern of nucleotides (in DNA or RNA) or amino acids (in proteins) that has remained relatively unchanged over evolutionary time. These sequences are often functionally important and are highly conserved across different species, indicating strong selection pressure against changes in these regions.

In the case of protein-coding genes, the corresponding amino acid sequence is deduced from the DNA sequence through the genetic code. Conserved sequences in proteins may indicate structurally or functionally important regions, such as active sites or binding sites, that are critical for the protein's activity. Similarly, conserved non-coding sequences in DNA may represent regulatory elements that control gene expression.

Identifying conserved sequences can be useful for inferring evolutionary relationships between species and for predicting the function of unknown genes or proteins.

Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.

The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.

Examples of animal disease models include:

1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.

Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.

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.

Notch receptors are a type of transmembrane receptor proteins that play crucial roles in cell-cell communication and regulation of various biological processes, including cell fate determination, differentiation, proliferation, and apoptosis. These receptors are highly conserved across species and are essential for normal development and tissue homeostasis.

The Notch signaling pathway is initiated when the extracellular domain of a Notch receptor on one cell interacts with its ligand (such as Delta or Jagged) on an adjacent cell. This interaction triggers a series of proteolytic cleavage events that release the intracellular domain of the Notch receptor, which then translocates to the nucleus and regulates gene expression by interacting with transcription factors like CSL (CBF1/RBP-Jκ/Su(H)/Lag-1).

There are four known Notch receptors in humans (Notch1-4) that share a similar structure, consisting of an extracellular domain containing multiple epidermal growth factor (EGF)-like repeats, a transmembrane domain, and an intracellular domain. Mutations or dysregulation of the Notch signaling pathway have been implicated in various human diseases, including cancer, cardiovascular disorders, and developmental abnormalities.

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.

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.

The eye is the organ of sight, primarily responsible for detecting and focusing on visual stimuli. It is a complex structure composed of various parts that work together to enable vision. Here are some of the main components of the eye:

1. Cornea: The clear front part of the eye that refracts light entering the eye and protects the eye from harmful particles and microorganisms.
2. Iris: The colored part of the eye that controls the amount of light reaching the retina by adjusting the size of the pupil.
3. Pupil: The opening in the center of the iris that allows light to enter the eye.
4. Lens: A biconvex structure located behind the iris that further refracts light and focuses it onto the retina.
5. Retina: A layer of light-sensitive cells (rods and cones) at the back of the eye that convert light into electrical signals, which are then transmitted to the brain via the optic nerve.
6. Optic Nerve: The nerve that carries visual information from the retina to the brain.
7. Vitreous: A clear, gel-like substance that fills the space between the lens and the retina, providing structural support to the eye.
8. Conjunctiva: A thin, transparent membrane that covers the front of the eye and the inner surface of the eyelids.
9. Extraocular Muscles: Six muscles that control the movement of the eye, allowing for proper alignment and focus.

The eye is a remarkable organ that allows us to perceive and interact with our surroundings. Various medical specialties, such as ophthalmology and optometry, are dedicated to the diagnosis, treatment, and management of various eye conditions and diseases.

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.

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.

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.

"Fish proteins" are not a recognized medical term or concept. However, fish is a source of protein that is often consumed in the human diet and has been studied in various medical and nutritional contexts. According to the USDA FoodData Central database, a 100-gram serving of cooked Atlantic salmon contains approximately 25 grams of protein.

Proteins from fish, like other animal proteins, are complete proteins, meaning they contain all nine essential amino acids that cannot be synthesized by the human body and must be obtained through the diet. Fish proteins have been studied for their potential health benefits, including their role in muscle growth and repair, immune function, and cardiovascular health.

It's worth noting that some people may have allergies to fish or seafood, which can cause a range of symptoms from mild skin irritation to severe anaphylaxis. If you suspect you have a fish allergy, it's important to consult with a healthcare professional for proper diagnosis and management.

The inner ear is the innermost part of the ear that contains the sensory organs for hearing and balance. It consists of a complex system of fluid-filled tubes and sacs called the vestibular system, which is responsible for maintaining balance and spatial orientation, and the cochlea, a spiral-shaped organ that converts sound vibrations into electrical signals that are sent to the brain.

The inner ear is located deep within the temporal bone of the skull and is protected by a bony labyrinth. The vestibular system includes the semicircular canals, which detect rotational movements of the head, and the otolith organs (the saccule and utricle), which detect linear acceleration and gravity.

Damage to the inner ear can result in hearing loss, tinnitus (ringing in the ears), vertigo (a spinning sensation), and balance problems.

Tetraodontiformes is not a medical term, but a taxonomic order in zoology. It refers to a group of marine fish that includes pufferfish, porcupinefish, boxfish, and triggerfish, among others. These fish are characterized by their specialized teeth, which are fused into beak-like structures. Some species within this order contain tetrodotoxin, a potent neurotoxin, in their organs. While not directly related to medical terminology, it is important for healthcare providers and medical professionals to have an understanding of various animal taxonomies, especially those that can pose a risk to human health.

Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a laboratory technique used in molecular biology to amplify and detect specific DNA sequences. This technique is particularly useful for the detection and quantification of RNA viruses, as well as for the analysis of gene expression.

The process involves two main steps: reverse transcription and polymerase chain reaction (PCR). In the first step, reverse transcriptase enzyme is used to convert RNA into complementary DNA (cDNA) by reading the template provided by the RNA molecule. This cDNA then serves as a template for the PCR amplification step.

In the second step, the PCR reaction uses two primers that flank the target DNA sequence and a thermostable polymerase enzyme to repeatedly copy the targeted cDNA sequence. The reaction mixture is heated and cooled in cycles, allowing the primers to anneal to the template, and the polymerase to extend the new strand. This results in exponential amplification of the target DNA sequence, making it possible to detect even small amounts of RNA or cDNA.

RT-PCR is a sensitive and specific technique that has many applications in medical research and diagnostics, including the detection of viruses such as HIV, hepatitis C virus, and SARS-CoV-2 (the virus that causes COVID-19). It can also be used to study gene expression, identify genetic mutations, and diagnose genetic disorders.

Veratrum alkaloids are a group of steroidal alkaloids found in plants belonging to the genus Veratrum, such as Veratrum album (white hellebore) and Veratrum viride (American false hellebore). These compounds have complex structures and can be divided into several types, including veratrine, jervine, and cevadine. They have various pharmacological effects, such as being anticholinergic, antiarrhythmic, and emetic. Veratrum alkaloids are used in traditional medicine, but they can also be highly toxic if ingested or handled improperly.

Basic Helix-Loop-Helix (bHLH) transcription factors are a type of proteins that regulate gene expression through binding to specific DNA sequences. They play crucial roles in various biological processes, including cell growth, differentiation, and apoptosis. The bHLH domain is composed of two amphipathic α-helices separated by a loop region. This structure allows the formation of homodimers or heterodimers, which then bind to the E-box DNA motif (5'-CANNTG-3') to regulate transcription.

The bHLH family can be further divided into several subfamilies based on their sequence similarities and functional characteristics. Some members of this family are involved in the development and function of the nervous system, while others play critical roles in the development of muscle and bone. Dysregulation of bHLH transcription factors has been implicated in various human diseases, including cancer and neurodevelopmental disorders.

Growth Differentiation Factor 6 (GDF6) is a member of the transforming growth factor-beta (TGF-β) superfamily, which plays crucial roles in various biological processes such as cell growth, differentiation, and development. Specifically, GDF6 is involved in the regulation of skeletal development, joint formation, and limb morphogenesis. It has been shown to inhibit chondrogenic differentiation and promote osteogenic differentiation during bone development. Genetic variations in the GDF6 gene have been associated with certain musculoskeletal disorders, such as osteoarthritis and joint laxity.

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.

Cell movement, also known as cell motility, refers to the ability of cells to move independently and change their location within tissue or inside the body. This process is essential for various biological functions, including embryonic development, wound healing, immune responses, and cancer metastasis.

There are several types of cell movement, including:

1. **Crawling or mesenchymal migration:** Cells move by extending and retracting protrusions called pseudopodia or filopodia, which contain actin filaments. This type of movement is common in fibroblasts, immune cells, and cancer cells during tissue invasion and metastasis.
2. **Amoeboid migration:** Cells move by changing their shape and squeezing through tight spaces without forming protrusions. This type of movement is often observed in white blood cells (leukocytes) as they migrate through the body to fight infections.
3. **Pseudopodial extension:** Cells extend pseudopodia, which are temporary cytoplasmic projections containing actin filaments. These protrusions help the cell explore its environment and move forward.
4. **Bacterial flagellar motion:** Bacteria use a whip-like structure called a flagellum to propel themselves through their environment. The rotation of the flagellum is driven by a molecular motor in the bacterial cell membrane.
5. **Ciliary and ependymal movement:** Ciliated cells, such as those lining the respiratory tract and fallopian tubes, have hair-like structures called cilia that beat in coordinated waves to move fluids or mucus across the cell surface.

Cell movement is regulated by a complex interplay of signaling pathways, cytoskeletal rearrangements, and adhesion molecules, which enable cells to respond to environmental cues and navigate through tissues.

Jaw abnormalities, also known as maxillofacial abnormalities, refer to any structural or functional deviations from the normal anatomy and physiology of the jaw bones (mandible and maxilla) and the temporomandibular joint (TMJ). These abnormalities can be present at birth (congenital) or acquired later in life due to various factors such as trauma, infection, tumors, or degenerative diseases.

Examples of jaw abnormalities include:

1. Micrognathia: a condition where the lower jaw is underdeveloped and appears recessed or small.
2. Prognathism: a condition where the lower jaw protrudes forward beyond the normal position.
3. Maxillary hypoplasia/aplasia: a condition where the upper jaw is underdeveloped or absent.
4. Mandibular hypoplasia/aplasia: a condition where the lower jaw is underdeveloped or absent.
5. Condylar hyperplasia: a condition where one or both of the condyles (the rounded ends of the mandible that articulate with the skull) continue to grow abnormally, leading to an asymmetrical jaw and facial deformity.
6. TMJ disorders: conditions affecting the temporomandibular joint, causing pain, stiffness, and limited movement.
7. Jaw tumors or cysts: abnormal growths that can affect the function and structure of the jaw bones.

Jaw abnormalities can cause various problems, including difficulty with chewing, speaking, breathing, and swallowing, as well as aesthetic concerns. Treatment options may include orthodontic treatment, surgery, or a combination of both, depending on the severity and nature of the abnormality.

'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.

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.

A genome is the complete set of genetic material (DNA, or in some viruses, RNA) present in a single cell of an organism. It includes all of the genes, both coding and noncoding, as well as other regulatory elements that together determine the unique characteristics of that organism. The human genome, for example, contains approximately 3 billion base pairs and about 20,000-25,000 protein-coding genes.

The term "genome" was first coined by Hans Winkler in 1920, derived from the word "gene" and the suffix "-ome," which refers to a complete set of something. The study of genomes is known as genomics.

Understanding the genome can provide valuable insights into the genetic basis of diseases, evolution, and other biological processes. With advancements in sequencing technologies, it has become possible to determine the entire genomic sequence of many organisms, including humans, and use this information for various applications such as personalized medicine, gene therapy, and biotechnology.

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.

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

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 transgene is a segment of DNA that has been artificially transferred from one organism to another, typically between different species, to introduce a new trait or characteristic. The term "transgene" specifically refers to the genetic material that has been transferred and has become integrated into the host organism's genome. This technology is often used in genetic engineering and biomedical research, including the development of genetically modified organisms (GMOs) for agricultural purposes or the creation of animal models for studying human diseases.

Transgenes can be created using various techniques, such as molecular cloning, where a desired gene is isolated, manipulated, and then inserted into a vector (a small DNA molecule, such as a plasmid) that can efficiently enter the host organism's cells. Once inside the cell, the transgene can integrate into the host genome, allowing for the expression of the new trait in the resulting transgenic organism.

It is important to note that while transgenes can provide valuable insights and benefits in research and agriculture, their use and release into the environment are subjects of ongoing debate due to concerns about potential ecological impacts and human health risks.

In medical terms, the heart is a muscular organ located in the thoracic cavity that functions as a pump to circulate blood throughout the body. It's responsible for delivering oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the rest of the body. The heart's rhythmic contractions and relaxations are regulated by a complex electrical conduction system.

Radiation hybrid (RH) mapping is a genetic mapping technique used to determine the relative order and distance between DNA markers or genes on a chromosome. This technique involves exposing donor cells, which contain the chromosome of interest, to high-dose radiation. The radiation causes breaks in the chromosomes, which are then repaired by fusing the donor cells with irradiated hamster cells (the recipient cells).

During the repair process, the broken chromosomal fragments from the donor cell randomly assort and integrate into the genome of the recipient cell. The resulting hybrid cells contain a mosaic of donor chromosomal fragments, which can be analyzed to determine the order and distance between DNA markers or genes on the original chromosome.

The frequency of co-occurrence of two markers in the same hybrid cell is used as an estimate of their physical proximity on the chromosome. The greater the frequency of co-occurrence, the closer the two markers are assumed to be. RH mapping can provide high-resolution maps of large genomes and has been widely used for mapping human and other mammalian genomes. However, with the advent of next-generation sequencing technologies, RH mapping has largely been replaced by sequence-based methods such as whole-genome sequencing and optical mapping.

Gene expression profiling is a laboratory technique used to measure the activity (expression) of thousands of genes at once. This technique allows researchers and clinicians to identify which genes are turned on or off in a particular cell, tissue, or organism under specific conditions, such as during health, disease, development, or in response to various treatments.

The process typically involves isolating RNA from the cells or tissues of interest, converting it into complementary DNA (cDNA), and then using microarray or high-throughput sequencing technologies to determine which genes are expressed and at what levels. The resulting data can be used to identify patterns of gene expression that are associated with specific biological states or processes, providing valuable insights into the underlying molecular mechanisms of diseases and potential targets for therapeutic intervention.

In recent years, gene expression profiling has become an essential tool in various fields, including cancer research, drug discovery, and personalized medicine, where it is used to identify biomarkers of disease, predict patient outcomes, and guide treatment decisions.

Blood vessels are the part of the circulatory system that transport blood throughout the body. They form a network of tubes that carry blood to and from the heart, lungs, and other organs. The main types of blood vessels are arteries, veins, and capillaries. Arteries carry oxygenated blood away from the heart to the rest of the body, while veins return deoxygenated blood back to the heart. Capillaries connect arteries and veins and facilitate the exchange of oxygen, nutrients, and waste materials between the blood and the body's tissues.

Gills are specialized respiratory organs found in many aquatic organisms such as fish, crustaceans, and some mollusks. They are typically thin, feathery structures that increase the surface area for gas exchange between the water and the animal's bloodstream. Gills extract oxygen from water while simultaneously expelling carbon dioxide.

In fish, gills are located in the gill chamber, which is covered by opercula or protective bony flaps. Water enters through the mouth, flows over the gills, and exits through the opercular openings. The movement of water over the gills allows for the diffusion of oxygen and carbon dioxide across the gill filaments and lamellae, which are the thin plates where gas exchange occurs.

Gills contain a rich supply of blood vessels, allowing for efficient transport of oxygen to the body's tissues and removal of carbon dioxide. The counter-current flow of water and blood in the gills ensures that the concentration gradient between the water and the blood is maximized, enhancing the efficiency of gas exchange.

Gene expression is the process by which the information encoded in a gene is used to synthesize a functional gene product, such as a protein or RNA molecule. This process involves several steps: transcription, RNA processing, and translation. During transcription, the genetic information in DNA is copied into a complementary RNA molecule, known as messenger RNA (mRNA). The mRNA then undergoes RNA processing, which includes adding a cap and tail to the mRNA and splicing out non-coding regions called introns. The resulting mature mRNA is then translated into a protein on ribosomes in the cytoplasm through the process of translation.

The regulation of gene expression is a complex and highly controlled process that allows cells to respond to changes in their environment, such as growth factors, hormones, and stress signals. This regulation can occur at various stages of gene expression, including transcriptional activation or repression, RNA processing, mRNA stability, and translation. Dysregulation of gene expression has been implicated in many diseases, including cancer, genetic disorders, and neurological conditions.

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.

Cilia are tiny, hair-like structures that protrude from the surface of many types of cells in the body. They are composed of a core bundle of microtubules surrounded by a protein matrix and are covered with a membrane. Cilia are involved in various cellular functions, including movement of fluid or mucus across the cell surface, detection of external stimuli, and regulation of signaling pathways.

There are two types of cilia: motile and non-motile. Motile cilia are able to move in a coordinated manner to propel fluids or particles across a surface, such as those found in the respiratory tract and reproductive organs. Non-motile cilia, also known as primary cilia, are present on most cells in the body and serve as sensory organelles that detect chemical and mechanical signals from the environment.

Defects in cilia structure or function can lead to a variety of diseases, collectively known as ciliopathies. These conditions can affect multiple organs and systems in the body, including the brain, kidneys, liver, and eyes. Examples of ciliopathies include polycystic kidney disease, Bardet-Biedl syndrome, and Meckel-Gruber syndrome.

'Animal behavior' refers to the actions or responses of animals to various stimuli, including their interactions with the environment and other individuals. It is the study of the actions of animals, whether they are instinctual, learned, or a combination of both. Animal behavior includes communication, mating, foraging, predator avoidance, and social organization, among other things. The scientific study of animal behavior is called ethology. This field seeks to understand the evolutionary basis for behaviors as well as their physiological and psychological mechanisms.

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.

"Dietary Protein Requirements of Zebrafish (Dania rerio)". Journal of Limnology and Freshwater Fisheries Research. 5 (1): 34-40 ...
"The Sperm Protein Spaca6 is Essential for Fertilization in Zebrafish". Frontiers in Cell and Developmental Biology. 9: 806982. ... Her lab uses zebrafish as the main model organism. Andrea Pauli is a group leader at the Research Institute of Molecular ... Since 2018, Pauli teaches zebrafish summer courses at the Marine Biological Laboratory in Woods Hole and in 2020, she became ... Focusing on fertilisation, Pauli and her lab identified the egg protein Bouncer as an essential factor for sperm-egg ...
Tallafuss, Alexandra; Trepman, Alissa; Eisen, Judith S. (2009-12-01). "DeltaA mRNA and protein distribution in the zebrafish ... This can be a gene co-expression network, or a protein-protein interaction (PPI) network. The nodes of the network will be ... Several of these protein disrupting mutations have been able to be identified only with the aid of whole genome sequencing ... The zebrafish model system has already been used to study neuroregeneration and severe polygenic human diseases like cancer and ...
"Patterning the zebrafish diencephalon by the conserved zinc-finger protein Fezl". Development. 134 (1): 127-36. doi:10.1242/dev ... In zebrafish, it was shown that the expression of two SHH genes, SHH-a and SHH-b (formerly described as twhh) mark the MDO ... "Hedgehog signalling from the zona limitans intrathalamica orchestrates patterning of the zebrafish diencephalon". Development. ...
... the PGCs express two CXCR4 transmembrane receptor proteins. The signaling system involving this protein and its ligand, Sdf1, ... Regardless of PGC injection site, PGCs are able to correctly migrate to their target sites.[citation needed] In zebrafish, ... Bone morphogenetic protein 4 (BMP4) is released by the extra-embryonic ectoderm (ExE) at embryonic day 5.5 to 5.75 directly ... December 2017). "The Vertebrate Protein Dead End Maintains Primordial Germ Cell Fate by Inhibiting Somatic Differentiation". ...
Chang, M. X.; Nie, P.; Wei, L. L. (April 2007). "Short and long peptidoglycan recognition proteins (PGRPs) in zebrafish, with ... Peptidoglycan recognition protein 1 Peptidoglycan recognition protein 2 Peptidoglycan recognition protein 3 Peptidoglycan ... Chang, M. X.; Wang, Y. P.; Nie, P. (February 2009). "Zebrafish peptidoglycan recognition protein SC (zfPGRP-SC) mediates ... Chang, M. X.; Nie, P. (2008-08-15). "RNAi suppression of zebrafish peptidoglycan recognition protein 6 (zfPGRP6) mediated ...
Kelly, Gregory M; Reversade, Bruno (1997). "Characterization of a cDNA encoding a novel band 4.1-like protein in zebrafish". ... BRAWNIN In 2020, he participated in the characterization of C12orf73, a protein-coding gene responsible for the making of a 71 ... In 2005, Reversade and De Robertis detailed how multiple extracellular proteins allow embryos that are cut in two to self- ... This small peptide is essential for respiratory chain complex III (CIII) assembly in human cells and zebrafish. C2orf69 In 2021 ...
Wang H (February 2010). "Characterization of zebrafish Esrom (Myc-binding protein 2) RCC1-like domain splice variants". Mol ... Highwire (Hiw) is an E3 ubiquitin ligase protein associated with neuromuscular junction growth. It is frequently studied in ...
"Zebrafish Peptidoglycan Recognition Proteins Are Bactericidal Amidases Essential for Defense against Bacterial Infections". ... He determined the role of DNA synthesis, intracellular calcium, protein kinase C, and inhibitory G proteins in peptidoglycan- ... "Peptidoglycan Recognition Proteins Are a New Class of Human Bactericidal Proteins". Journal of Biological Chemistry. 281 (9): ... "Peptidoglycan recognition proteins kill bacteria by activating protein-sensing two-component systems". Nature Medicine. 17 (6 ...
"Differential calcium signaling by cone specific guanylate cyclase-activing proteins from the zebrafish retina". PLOS ONE. 6 (8 ... In addition, studies have shown that zebrafish express a higher number of GCAPs than mammals, and that zebrafish GCAPs can bind ... Depending on cell type, it can drive adaptive/developmental changes requiring protein synthesis. In smooth muscle, cGMP is the ... Low concentrations of calcium cause the dimerization of RETGC-1 proteins through stimulation from guanylate cyclase-activating ...
Currie PD, Ingham PW (August 1996). "Induction of a specific muscle cell type by a hedgehog-like protein in zebrafish". Nature ... Sonic hedgehog protein (SHH) is encoded for by the SHH gene. The protein is named after the character Sonic the Hedgehog. This ... "Zebrafish SHHa". University of Oregon. Archived from the original on 2009-06-25. "Zebrafish SHHb". University of Oregon. ... SHH is located on chromosome seven and initiates the production of Sonic Hedgehog protein. This protein sends short- and long- ...
... "nacre encodes a zebrafish microphthalmia-related protein that regulates neural-crest-derived pigment cell fate". Development. ... Protein kinase C-interacting protein 1 (PKC1) associates with MITF. Their association is reduced upon cell activation. When ... Microphthalmia-associated transcription factor also known as class E basic helix-loop-helix protein 32 or bHLHe32 is a protein ... Most transcription factors function in cooperation with other factors by protein-protein interactions. Association of MITF with ...
Morpholino knockdown of MagT1 and TUSC3 protein expression in zebrafish embryos resulted in early developmental arrest; excess ... Protein families, Membrane proteins, Transmembrane proteins, Transmembrane transporters, Transport proteins, Integral membrane ... They designated this protein, MagT1. MagT1 is expressed as a 335 amino acid polypeptide which includes five transmembrane ... Knockdown of either MagT1 or TUSC3 protein lowered the total and free intracellular Mg2+concentrations in mammalian cell lines ...
Using zebrafish, Larhammar explores the localization and functions of the memory proteins. His team works on discovering at ... mRNA production of protein, but did not block its own species' mRNA. The inhibiting substance however did not prevent protein ... Each vole species was found to have a substance that blocked the production of protein from the other two species' ... As of 2021 Larhammar leads a research team at Uppsala that studies receptors for brain neurotransmitters and uses zebrafish as ...
... is tied to liver development in an orthologous protein in zebrafish. The function of the human UPF0762 is not yet well ... DUF781 is the singular domain of the protein and spans 318 of the protein's 330 amino acids. DUF781 has been linked to liver ... "liver-enriched gene 1a and 1b encode novel secretory proteins essential for normal liver development in zebrafish". PLOS ONE. 6 ... "Analysis of vaccinia virus-host protein-protein interactions: validations of yeast two-hybrid screenings". J. Proteome Res. 8 ( ...
"Biochemical and cellular characteristics of the four splice variants of protein kinase CK1alpha from zebrafish (Danio rerio)". ... The AD hallmark proteins tau in NFTs or GVBs and TAR DNA-binding protein of 43 kDa (TDP-43) in GVBs colocalize with CK1δ. In ... So far, C-terminal phosphorylation of CK1δ by upstream kinases has been confirmed for protein kinase A (PKA), protein kinase B ... Locasale JW, Shaw AS, Chakraborty AK (August 2007). "Scaffold proteins confer diverse regulatory properties to protein kinase ...
... a newly identified pleckstrin homology domain protein, is required for cardiac contractility in zebrafish". Disease Models & ... The protein PDZD11 was identified as a protein interacting through its N-terminal region with the N-terminal WW domain of ... The protein was discovered in Masatoshi Takeichi's lab while looking for potential binding partners for the N-terminal region ... Tille JC, Ho L, Shah J, Seyde O, McKee TA, Citi S (2015-01-01). "The Expression of the Zonula Adhaerens Protein PLEKHA7 Is ...
Two other family members that are not obvious orthologs of any identified mammalian FXYD protein exist in zebrafish. All these ... The FXYD protein family is a family of small membrane proteins that share a 35-amino acid signature sequence domain, beginning ... This article incorporates text from the public domain Pfam and InterPro: IPR000272 (Protein domains, Protein families, Single- ... FXYD proteins appear to preferentially associate with Na,K-ATPase alpha1-beta isozymes, and affect their function in a way that ...
In this study, scientists used zebrafish to examine the motion of proteins within live ear cells using a confocal microscope. ... Fascin 2b, a protein involved in actin cross-linking, moves even faster. Constant movement of proteins within cells, along with ... This has shown that proteins in stereocilia move quickly, indicating that the movement of the proteins within the hair cells ... The fast movement of these proteins has changed our understanding of stereocilia and indicates that proteins within stereocilia ...
"Mutations in the microtubule-associated protein MAP11 (C7orf43) cause microcephaly in humans and zebrafish". Brain: A Journal ... "The 60-kDa heat shock protein modulates allograft rejection". Proceedings of the National Academy of Sciences of the United ... A microcephaly syndrome caused by mutations in the microtubule-associated protein MAP11 (C7orf43, TRAPPC14, MCPH25). ...
It encodes a protein showing 95%, 86%, and 71% amino acid identity to the mouse, zebrafish and Xenopus Wnt8B proteins, ... Protein Wnt-8b is a protein that in humans is encoded by the WNT8B gene. The WNT gene family consists of structurally related ... These proteins have been implicated in oncogenesis and in several developmental processes, including regulation of cell fate ... Smolich BD, McMahon JA, McMahon AP, Papkoff J (1994). "Wnt family proteins are secreted and associated with the cell surface". ...
It was originally identified during a search for immune system genes in zebrafish as a protein coding sequence related to APAF1 ... NWD1, short for NACHT and WD repeat domain containing 1, is a gene found in vertebrates, which encodes a protein that contains ... Correa RG, Krajewska M, Ware CF, Gerlic M, Reed JC (2014). "The NLR-related protein NWD1 is associated with prostate cancer and ... "Conservation and divergence of gene families encoding components of innate immune response systems in zebrafish". Genome Biol. ...
... with homology to an Escherichia coli and a zebrafish protein that maps to chromosome 21q22.3". Hum Genet. 99 (5): 616-23. doi: ... 1996). "Isolation of cDNA for a novel human protein KNP-I that is homologous to the E. coli SCRP-27A protein from the ... Glutamine amidotransferase-like class 1 domain-containing protein 3A, mitochondrial is a protein that in humans is encoded by ... 1993). "Human liver protein map: a reference database established by microsequencing and gel comparison". Electrophoresis. 13 ( ...
"A role for the Myoblast city homologues Dock1 and Dock5 and the adaptor proteins Crk and Crk-like in zebrafish myoblast fusion ... Dedicator of cytokinesis protein 5 (Dock5) is a large (~180 kDa) protein encoded in the human by the DOCK5 gene, involved in ... which function as activators of small G-proteins. Dock5 is predicted to activate the small G protein Rac. Dock5 shares ... Meller N, Merlot S, Guda C (2005). "CZH proteins: a new family of Rho-GEFs". J. Cell Sci. 118 (Pt 21): 4937-46. doi:10.1242/jcs ...
Human and zebrafish BMAL2 proteins contained only 66% of the same amino acids, rather than 85% between human and zebrafish ... The MOP9 protein, like the MOP3 protein, was also found to form heterodimers with MOP4 and hypoxia-inducible factors including ... as well as in zebrafish. ARNTL2 genes differ significantly more between species than ARNTL genes- BMAL2 proteins have diverged ... The BMAL2 protein follows the basic helix-loop-helix structure of the PER-ARNT-SIM family and contains a bHLH-PAS domain in its ...
In zebrafish, the interconnectivity of proteins over developmental time was found to be highest in early development, ... re-analyzed the zebrafish dataset published by Domazet-Lošo and Tautz. They found that applying a log-transformation to the ... In zebrafish, as well as in additional transcriptomic datasets of Drosophila, the mosquito Anopheles and the nematode ... Gene knockout experiments from mice and zebrafish demonstrated that the ratio of essential genes to non-essential genes ...
The enzyme is implicated in the trafficking and signaling of type I bone morphogenetic protein (BMP) receptors in zebra fish ( ... The gene encodes SPTLC1 protein, which together with SPTLC2 protein, forms serine palmitoyltransferase (SPT) in humans. SPT is ... The gene encodes SPTLC2 protein which is one of two subunits of SPT. As mutations in the gene affect the same enzyme as those ... The protein also has de novo DNA methyltransferase activity which is responsible for establishing methylation patterns during ...
"A role for the Myoblast city homologues Dock1 and Dock5 and the adaptor proteins Crk and Crk-like in zebrafish myoblast fusion ... Dedicator of cytokinesis protein 1 (Dock1), also (DOCK180), is a large (~180 kDa) protein encoded in the human by the DOCK1 ... Subsequently it was reported that DOCK180 was able to activate the small GTP-binding protein (G protein) Rac1 and this was ... GEFs activate G proteins by promoting this nucleotide exchange. DOCK180 and related proteins differ from other GEFs in that ...
Several groups have been developing zebrafish to detect pollution by attaching fluorescent proteins to genes activated by the ... There is also potential to use the silk producing machinery to make other valuable proteins. Proteins expressed by silkworms ... Human proteins expressed in mammals are more likely to be similar to their natural counterparts than those expressed in plants ... Human alpha-1-antitrypsin is another protein that is used in treating humans with this deficiency. Another area is in creating ...
Several groups have been developing zebrafish to detect pollution by attaching fluorescent proteins to genes activated by the ... The majority of these products are human proteins for use in medicine. Many of these proteins are impossible or difficult to ... There is also potential to use the silk producing machinery to make other valuable proteins. Proteins currently developed to be ... Human proteins expressed in mammals are more likely to be similar to their natural counterparts than those expressed in plants ...
Genomics study identifies unique set of proteins that restores hearing in zebrafish. NIH study shows the role of transcription ... Jimenez and her collaborators found that hair cell regeneration in zebrafish relied on a network of proteins that can switch ... Humans and zebrafish are visually quite different, but at a genomic level, they share more than 70% of their genes. This ... Confocal image of adult zebrafish hair cells (green) in the auditory organ of the inner ear. Erin Jimenez, Ph.D., NHGRI. ...
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Spliceosomal protein eftud2 mutation leads to p53-dependent apoptosis in zebrafish neural progenitors Lei Lei 1 , Shou-Yu Yan 1 ... Spliceosomal protein eftud2 mutation leads to p53-dependent apoptosis in zebrafish neural progenitors Lei Lei et al. Nucleic ... D) Western blot showing that Eftud2 protein was not detectable in fn10a−/− mutants. β-Actin was used to normalize protein ... The fn10a locus encodes Eftud2 in zebrafish. (A) Regional fine-map of fn10a with the flanking genetic markers in chromosome 3, ...
B) The alignment of the human ZRSR2 protein with isoforms 201 and 204 of zebrafish Zrsr2, showing the location of conserved ... Zrsr2 Is Essential for the Embryonic Development and Splicing of Minor Introns in RNA and Protein Processing Genes in Zebrafish ... Zrsr2 Is Essential for the Embryonic Development and Splicing of Minor Introns in RNA and Protein Processing Genes in Zebrafish ... Tronchere H., Wang J., Fu X.D. A protein related to splicing factor U2AF35 that interacts with U2AF65 and SR proteins in ...
DANRE A0A0R4IVV0 Microsomal triglyceride transfer protein large subunit ...
New organism-specific proteins include:. *Zebrafish Proteins *Fish Proteins *Saccharomyces cerevisiae Proteins * ... Xenopus Proteins *Amphibian Proteins *Arabidopsis Proteins *Soybean Proteins *Avian Proteins *Drosophila Proteins Generally, ...
Zebrafish Proteins Grants and funding * U01 DK062481/DK/NIDDK NIH HHS/United States ... and zebrafish. Zebrafish abcc12-null mutants were prone to cholangiocyte apoptosis, which caused progressive bile duct loss ... ABCC12 encodes multidrug resistance-associated protein 9 (MRP9) that belongs to the adenosine 5-triphosphate-binding cassette ... Immunohistochemistry and Western blotting revealed conserved MRP9 protein expression in the bile ducts in human, mouse, ...
The cdy mutant has a premature stop codon in the zebrafish homolog of dmt1, resulting in a severely truncated protein. The ... In addition, the zebrafish sepp gene contains duplicated Sec insertion sequence elements and encodes a protein containing 17 ... confirming the existence of zebrafish ZNT10 and ZIP5 in zebrafish. The homology of zinc transporters among zebrafish, mice and ... These same defects were also observed in zebrafish morphants in which the zinc-finger protein Snail, a master regulator of EMT ...
Functional characterization of zebrafish cytochrome P450 1 family proteins expressed in yeast. Biochim Biophys Acta 1850(11): ... A review of the functional roles of the zebrafish aryl hydrocarbon receptors. Toxicol Sci. 178(2):215-238. doi:10.1093/toxsci/ ... Role of DNA methylation in altered gene expression patterns in adult zebrafish (Danio rerio) exposed to 3, 3, 4, 4, 5- ... A review of the functional roles of the zebrafish aryl hydrocarbon receptors. Toxicol Sci. 178(2):215-238. doi:10.1093/toxsci/ ...
Zebrafish Proteins. Beaver LM, Nkrumah-Elie YM, Truong L, Barton CL, Knecht AL, Gonnerman GD, Wong CP, Tanguay RL, Ho E. 2017. ... Zebrafish. Beaver LM, Nkrumah-Elie YM, Truong L, Barton CL, Knecht AL, Gonnerman GD, Wong CP, Tanguay RL, Ho E. 2017. Adverse ... Adverse effects of parental zinc deficiency on metal homeostasis and embryonic development in a zebrafish model.. J Nutr ... Adverse effects of parental zinc deficiency on metal homeostasis and embryonic development in a zebrafish model.. J Nutr ...
Zebrafish; Zebrafish Proteins/deficiency; Zebrafish Proteins/genetics ... Protein Conformation; Protein-Serine-Threonine Kinases/deficiency; Protein-Serine-Threonine Kinases/genetics; RNA Processing, ... Intracellular Signaling Peptides and Proteins/deficiency; Intracellular Signaling Peptides and Proteins/genetics; ... CRISPR-Cas9 knockout in zebrafish and mice recapitulated the human phenotype of primary microcephaly and resulted in early ...
For example, depleting a protein called furin stunted head growth in zebrafish by nearly a fourth. Knocking down the FURIN gene ...
To study function of these proteins we also use zebrafish as a model system. ... We use a zebrafish model to study functions of Olfm1 in development. There are two olfm1 genes in zebrafish, each producing ... Functions of the olfactomedin domain-containing proteins The family of olfactomedin domain-containing proteins is one of the ... We produced a zebrafish line with null mutations in both olfm1 genes showing interesting phenotype. The functions of Olfm1-3 ...
... an ACS physician scientist genetically altered zebrafish to make the droplets fluorescent. ... To better see the lipid droplets in action, Whites lab team genetically engineered zebrafish so that a key protein in lipid ... ACS grantee and clinical researcher, Richard White, MD, PhD, explains why his lab zebrafish uses zebrafish to study cancer. ... Zebrafish are also cheap, easy to genetically engineer, and they get cancer in the wild, with mechanisms that are similar to ...
2005) The repertoire of trace amine G-protein-coupled receptors: large expansion in zebrafish. Mol Phylogenet Evol 35:470-482, ... To assess the distribution of the macaque OE and its complement of OSNs, we first examined OMP, a protein expressed by rodent, ... 1982) Olfactory marker protein (OMP) Scand J Immunol Suppl 9:181-199, pmid:6963760. ... 1991) Localization of tyrosine hydroxylase and olfactory marker protein immunoreactivities in the human and macaque olfactory ...
Pbx homeodomain proteins pattern both the zebrafish retina and tectum. French CR; Erickson T; Callander D; Berry KM; Koss R; ... Sequentially acting SOX proteins orchestrate astrocyte- and oligodendrocyte-specific gene expression. Klum S; Zaouter C; ...
Zebrafish zrsr2 protein shows 78% similarity to human ZRSR2. Therefore, since the function of ZRSR2 in the hematopoietic system ... Mutation in the splicing factor zrsr2 disrupts normal hematopoietic development in zebrafish. Wednesday, September 13, 2017. - ... Overall, the hematopoietic phenotypes observed in zrsr2del11/del11 zebrafish embryos suggests that we generated a promising ... is poorly understood and, to date, there are no animal models available, we decided to use zebrafish as a model to investigate ...
This article reviews the PINK1 protein product, which has been implicated in several functions, mostly aimed at protecting ... Y2H, pulldown (Zebrafish) Plasma membrane, TGN. Calcium-sensing molecule. Not reported. Development of brain and inner ear in ... The experimental evidence reviewed here clearly identifies PINK1 as one of these proteins (Figure 2). Research on such proteins ... PINK1: One Protein, Multiple Neuroprotective Functions. Enza Maria Valente, MD, PhD; Silvia Michiorri, BSc; Giuseppe Arena, BSc ...
5. Ribosomal protein L11 mutation in zebrafish leads to haematopoietic and metabolic defects.. Danilova N; Sakamoto KM; Lin S. ... Defects of protein production in erythroid cells revealed in a zebrafish Diamond-Blackfan anemia model for mutation in RPS19. ... 2. Ribosomal protein deficiency causes Tp53-independent erythropoiesis failure in zebrafish.. Yadav GV; Chakraborty A; Uechi T ... Ribosomal protein S24 gene is mutated in Diamond-Blackfan anemia.. Gazda HT; Grabowska A; Merida-Long LB; Latawiec E; Schneider ...
... and Protein Kinases (R03 Clinical Trial Not Allowed) RFA-RM-22-024 PI Name Institution Name Title ALDINGER, KIMBERLY ANNE ... Pilot Projects Investigating Understudied G Protein-Coupled Receptors, Ion Channels, ... Phosphoproteomic Analyses of Understudied Protein Kinases that affect Zebrafish Sleep. SACK, JON THOMAS (contact). FERNS, ... Functional characterization of understudied protein kinases implicated in developmental disorders using zebrafish. ...
Increased functional protein expression using nucleotide sequence features enriched in highly expressed genes in zebrafish. ... Increased functional protein expression using nucleotide sequence features enriched in highly expressed genes in zebrafish. ... Hong SK, Levin CS, Brown JL, Wan H, Sherman BT, Huang da W, Lempicki RA, Feldman B. Pre-gastrula expression of zebrafish ... Zebrafish mutants identify an essential role for laminins in notochord formation. Development. 2002 Jul;129(13):3137-46. PMID: ...
Thats why scientists around the world have been studying a striped fish called the zebrafish. ... The researchers found a way to block key proteins that fuel the growth of new blood vessels in zebrafish. Then they showed that ... "Zebrafish are a good model for humans in many ways," says Dr. Brant Weinstein, an NIH expert in zebrafish biology. "We have a ... In fact, zebrafish and people share more than 70% of their genes. So theyre ideal for studying how various genes can affect ...
Based on the functions of similar proteins in other organisms (such as zebrafish and mice), the SALL4 protein appears to play a ... This protein may also be important for the development of nerves that control eye movement and for the formation of the walls ( ... SALL proteins are transcription factors, which means they attach (bind) to specific regions of DNA and help control the ... Most SALL4 gene mutations create a premature stop signal in the instructions for making the SALL4 protein. As a result, cells ...
To increase the number of glycopeptides, proteins from zebrafish were digested with two different proteases--chymotrypsin and ... Zebrafish (Danio rerio) is a model organism that is used to study the mechanisms and pathways of human disorders. Many ... This proteomics data will expand our knowledge about glycoproteins in zebrafish and may be used to elucidate the role that ... The N-glycosylated peptides of zebrafish were then captured by the solid-phase extraction of N-linked glycopeptides (SPEG) ...
A fourth model system uses Rohon-Beard primary sensory neurons from Zebrafish to identify how G-protein coupled receptors ... and the Section is currently examining the activation of this protein complex in living zebrafish hearts. The third project ... The first involves the construction of a microscope that can be used to study protein complexes in living cells by measuring ... The Section on Cellular Biophotonics studies how protein complexes are formed and maintained in living cells, and how these ...
15-Zinc finger protein Bloody Fingers is required for zebrafish morphogenetic movements during neurulation. Authors Sumanas, S ... 15-Zinc finger protein Bloody Fingers is required for zebrafish morphogenetic movements during neurulation, 85-96, Copyright ( ... Home page banner reprinted from Hearing Research, 341, Monroe, J.D. et al., Hearing sensitivity differs between zebrafish lines ...
Zebrafish, Zebrafish Proteins/genetics", ... KW - Zebrafish Proteins/genetics. U2 - 10.1016/j.neuron.2015.10 ... circuits in the tectum of astray mutant zebrafish in which lamination of retinal ganglion cell (RGC) axons is lost. We show ... circuits in the tectum of astray mutant zebrafish in which lamination of retinal ganglion cell (RGC) axons is lost. We show ... circuits in the tectum of astray mutant zebrafish in which lamination of retinal ganglion cell (RGC) axons is lost. We show ...
Based on the functions of similar proteins in other organisms (such as zebrafish and mice), the SALL4 protein appears to play a ... This protein may also be important for the development of nerves that control eye movement and for the formation of the walls ( ... SALL proteins are transcription factors, which means they attach (bind) to specific regions of DNA and help control the ... Most SALL4 gene mutations create a premature stop signal in the instructions for making the SALL4 protein. As a result, cells ...
  • Green fluorescent protein (GFP) as a marker of aryl hydrocarbon receptor (AhR) function in developing zebrafish (Danio rerio). (nih.gov)
  • Among these species, the zebrafish ( Danio rerio ) has been a valuable vertebrate system with several unique advantages. (frontiersin.org)
  • Zebrafish (Danio rerio) is a model organism that is used to study the mechanisms and pathways of human disorders. (nih.gov)
  • 2006). Osteocalcin and matrix Gla protein in zebrafish (Danio rerio) and Senegal sole (Solea senegalensis): Comparative gene and protein expression during larval development through adulthood . (up.pt)
  • Adverse effects of parental zinc deficiency on metal homeostasis and embryonic development in a zebrafish model. (oregonstate.edu)
  • 18. p53-Independent cell cycle and erythroid differentiation defects in murine embryonic stem cells haploinsufficient for Diamond Blackfan anemia-proteins: RPS19 versus RPL5. (nih.gov)
  • These genes provide instructions for making proteins that are involved in the formation of tissues and organs during embryonic development. (medlineplus.gov)
  • Many dysfunctions in neurological, development, and neuromuscular systems are due to glycosylation deficiencies, but the glycoproteins involved in zebrafish embryonic development have not been established. (nih.gov)
  • The identified glycoproteins were highly abundant in proteins belonging to the transporter, cell adhesion, and ion channel/ion binding categories, which are important to embryonic, organ, and central nervous system development. (nih.gov)
  • Zebrafish was utilized as our model organism to study the changes in Notch signaling during trabeculation since they provide many advantages in studying these developmental phenomena, such as rapid organ development, high fecundity, and are optically transparent during early embryonic stages. (escholarship.org)
  • Furthermore, we utilized adult zebrafish to study cardiac regeneration in addition to the embryonic model. (escholarship.org)
  • Increased functional protein expression using nucleotide sequence features enriched in highly expressed genes in zebrafish. (nih.gov)
  • Effects of xenoestrogens on the expression of vitellogenin (vtg) and cytochrome P450 aromatase (cyp19a and b) genes in zebrafish (Daniorerio) larvae. (x-mol.com)
  • View from above of a juvenile transgenic zebrafish. (nih.gov)
  • Zebrafish cardiac development can be visually assessed in transgenic zebrafish with fluorescently labeled proteins to visualize the heart or endocardium. (escholarship.org)
  • Secondly, because they are fertilized ex vivo and are optically transparent, zebrafish embryos are ideally suited for experimental techniques such as gene knockout/knockdown and overexpression. (frontiersin.org)
  • Overall, the hematopoietic phenotypes observed in zrsr2del11/del11 zebrafish embryos suggests that we generated a promising model to characterize the role of ZRSR2 in the hematopoietic system in vivo. (nih.gov)
  • In this study, a mass spectrometry-based glycoproteomic characterization of zebrafish embryos was performed to identify the N-linked glycoproteins and N-linked glycosylation sites. (nih.gov)
  • Protein Profiles in Zebrafish (Daniorerio) Embryos Exposed to PFOS. (x-mol.com)
  • Developmental toxicity and alteration of gene expression in zebrafish embryos exposed to PFOS. (x-mol.com)
  • The Role of Nrf2 and MAPK Pathways in PFOS-induced Oxidative Stress in Zebrafish Embryos. (x-mol.com)
  • Hexabromocyclododecane-induced developmental toxicity and apoptosis in zebrafish embryos. (x-mol.com)
  • To increase the number of glycopeptides, proteins from zebrafish were digested with two different proteases--chymotrypsin and trypsin--into peptides of different length. (nih.gov)
  • The N-glycosylated peptides of zebrafish were then captured by the solid-phase extraction of N-linked glycopeptides (SPEG) method and the peptides were identified with an LTQ OrbiTrap Velos mass spectrometer. (nih.gov)
  • Positional cloning revealed a nonsense mutation such that the mutant eftud2 mRNA encoded a truncated Eftud2 protein and was subjected to nonsense-mediated decay. (nih.gov)
  • 5. Ribosomal protein L11 mutation in zebrafish leads to haematopoietic and metabolic defects. (nih.gov)
  • 6. Mice with a Mutation in the Mdm2 Gene That Interferes with MDM2/Ribosomal Protein Binding Develop a Defect in Erythropoiesis. (nih.gov)
  • 14. Defects of protein production in erythroid cells revealed in a zebrafish Diamond-Blackfan anemia model for mutation in RPS19. (nih.gov)
  • The SALL4 gene mutation responsible for IVIC syndrome creates a premature stop signal in the instructions for making the SALL4 protein. (medlineplus.gov)
  • In this study, Masai and his lab identified one zebrafish strain carrying a mutation in the stem-loop binding protein, or SLBP. (oist.jp)
  • 9. Diamond Blackfan anemia: ribosomal proteins going rogue. (nih.gov)
  • Zebrafish abcc12-null mutants were prone to cholangiocyte apoptosis, which caused progressive bile duct loss during the juvenile stage. (nih.gov)
  • 10. Defective ribosomal protein gene expression alters transcription, translation, apoptosis, and oncogenic pathways in Diamond-Blackfan anemia. (nih.gov)
  • p53 is a critical tumor-suppressor protein that guards the human genome against mutations by inducing cell-cycle arrest or apoptosis. (rcsb.org)
  • Although hair cell loss cannot be replaced in humans, many animals, including zebrafish, can restore hearing after injury through the regeneration of hair cells. (nih.gov)
  • Humans and zebrafish are visually quite different, but at a genomic level, they share more than 70% of their genes. (nih.gov)
  • This genomic similarity offers the potential for researchers to understand the biology of cell regeneration in zebrafish before translating the findings to humans. (nih.gov)
  • Further down the line, this group of zebrafish transcription factors might become a biological target that may lead to the development of novel therapy to treat hearing loss in humans," Jimenez said. (nih.gov)
  • Zebrafish are also cheap, easy to genetically engineer, and they get cancer in the wild, with mechanisms that are similar to those in humans. (cancer.org)
  • Zebrafish are a good model for humans in many ways," says Dr. Brant Weinstein, an NIH expert in zebrafish biology. (nih.gov)
  • Unlike humans, zebrafish can regrow damaged limbs and other body parts. (nih.gov)
  • Zebrafish SLBP is homologous to human SLBP, meaning that despite how distantly related humans and zebrafish are, the genetic sequences look very similar and the protein appears to function in the same way. (oist.jp)
  • The development issues we see in zebrafish could be happening in humans," said Masai, "but we would not know because we cannot take out a human eye to examine it. (oist.jp)
  • Furthermore, the genes related to congenital heart disease genes in humans are conserved in zebrafish. (escholarship.org)
  • This study will provide a deeper understanding of the mechanisms that drive of cardiac morphogenesis in zebrafish model and contribute to developing therapies for humans with CHD. (escholarship.org)
  • To study the role of lipid droplets in cancer in a live organism, an ACS physician scientist genetically altered zebrafish to make the droplets fluorescent. (cancer.org)
  • To better see the lipid droplets in action, White's lab team genetically engineered zebrafish so that a key protein in lipid droplets would carry a fluorescent tag. (cancer.org)
  • This imaging is done with genetically modified zebrafish that express a fluorescent protein, such as GFP. (photometrics.com)
  • We then modulated zebrafish endocardial WSS by genetically reducing blood viscosity and hematopoeisis via gata1a-MO injection to examine changes in trabeculation. (escholarship.org)
  • National Institutes of Health researchers have discovered a specific network of proteins that is necessary to restore hearing in zebrafish through cell regeneration. (nih.gov)
  • The regenerative properties of zebrafish hair cells prompted researchers to use this animal to understand some fundamental properties of regeneration. (nih.gov)
  • Using a combination of genomic techniques and computational-based machine learning, Jimenez and her collaborators found that hair cell regeneration in zebrafish relied on a network of proteins that can switch genes on and off, known as transcription factors. (nih.gov)
  • Our study identified two families of transcription factors that work together to activate hair cell regeneration in zebrafish, called Sox and Six transcription factors," said Jimenez. (nih.gov)
  • We have identified a unique combination of transcription factors that trigger regeneration in zebrafish. (nih.gov)
  • We study genes, proteins and signaling pathways that might be essential for RGC and optic nerve development, function, survival, and regeneration. (nih.gov)
  • A regulatory network of Sox and Six transcription factors initiate a cell fate transformation during hearing regeneration in adult zebrafish. (nih.gov)
  • To study the electrical and mechanical changes in the zebrafish heart, we developed an ECG gated pulse-wave Doppler ultrasound device to monitor changes in cardiac electrical-mechanical properties during regeneration. (escholarship.org)
  • The experimental evidence reviewed here clearly identifies PINK1 as one of these proteins (Figure 2). (medscape.com)
  • Brown JL, Snir M, Noushmehr H, Kirby M, Hong SK, Elkahloun AG, Feldman B. Transcriptional profiling of endogenous germ layer precursor cells identifies dusp4 as an essential gene in zebrafish endoderm specification. (nih.gov)
  • Nodal-related signals establish mesendodermal fate and trunk neural identity in zebrafish. (nih.gov)
  • In zebrafish, neural crest-derived melanophores differentiate during embryogenesis to produce stripes in the early larva. (biologists.com)
  • As a model for studying trace mineral metabolism, the zebrafish is indispensable to researchers. (frontiersin.org)
  • Moreover, because of their developmental advantages, zebrafish have also been used in mineral metabolism-related chemical screens and toxicology studies. (frontiersin.org)
  • Finally, we discuss the evidence that zebrafish is an ideal experimental tool for uncovering novel mechanisms of trace mineral metabolism and for improving approaches to treat mineral imbalance-related diseases. (frontiersin.org)
  • CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 genome editing was used to induce frameshift pathogenic variants in the candidate gene in zebrafish and mice. (nih.gov)
  • Then they showed that blocking those proteins in mice could reduce tumor growth. (nih.gov)
  • Based on the functions of similar proteins in other organisms (such as zebrafish and mice), the SALL4 protein appears to play a critical role in the developing limbs. (medlineplus.gov)
  • Confocal image of adult zebrafish hair cells (green) in the auditory organ of the inner ear. (nih.gov)
  • A third model system provides a platform for expressing heterologous proteins in adult mammalian neurons by using in vitro -transcribed mRNA and a cationic lipid transfection reagent. (nih.gov)
  • 1. Dissecting the transcriptional phenotype of ribosomal protein deficiency: implications for Diamond-Blackfan Anemia. (nih.gov)
  • Professor Ichiro Masai, who heads the Okinawa Institute of Science and Technology Graduate University's Developmental Neurobiology Unit, has spent years screening zebrafish with developmental mutations to understand cell division and differentiation. (oist.jp)
  • American Cancer Society research grantee Richard White, MD, PhD, along with his students Dianne Lumaquin and Elenor Johns created a way to visually track lipid droplets using zebrafish . (cancer.org)
  • Zebrafish mutants identify an essential role for laminins in notochord formation. (nih.gov)
  • SLBP mutants in invertebrate animals showed defects in chromatin segregation, so Masai and his colleagues think that studying the protein in zebrafish could provide more insight. (oist.jp)
  • We surveyed the genome of children with chronic cholestasis for variants in genes not previously associated with liver disease and validated their biological relevance in zebrafish and murine models. (nih.gov)
  • Metalloproteins account for approximately half of all proteins and perform a wide range of biological functions as enzymes, transporters and signal transducers. (frontiersin.org)
  • Dr. Rui Ma is working on the development of optical microscopy systems at MPL, and is currently involved with building a light sheet microscope in order to image zebrafish, a biological model system used by colleagues at MPL to study spinal cord injury. (photometrics.com)
  • This protein was produced in an in vitro wheat germ expression system that should preserve correct conformational folding that is necessary for biological function. (novusbio.com)
  • However some animals, such as zebrafish, can regenerate hair cells and recover hearing after injury," said Burgess. (nih.gov)
  • Unlike the human heart, zebrafish hearts naturally regenerate and undergo rapid scar degradation. (escholarship.org)
  • Pei W, Williams PH, Clark MD, Stemple DL, Feldman B. Environmental and genetic modifiers of squint penetrance during zebrafish embryogenesis. (nih.gov)
  • 16. Ribosomal protein mutations induce autophagy through S6 kinase inhibition of the insulin pathway. (nih.gov)
  • Most SALL4 gene mutations create a premature stop signal in the instructions for making the SALL4 protein. (medlineplus.gov)
  • To properly identify which transcription factors were at play, the researchers first had to look at the enhancer sequences within the zebrafish genome. (nih.gov)
  • Specific amino acid sequences present in the primary amino acid sequence of proteins which mediate their export from the CELL NUCLEUS. (harvard.edu)
  • We report here the isolation, cloning and functional analysis of the mutated eftud2 (snu114) in a novel neuronal mutant fn10a in zebrafish. (nih.gov)
  • We demonstrated that Olfm1 interacts with several proteins essential for neuronal and synaptic activity. (nih.gov)
  • The Section on Transmitter Signaling considers the way G-protein coupled receptors modulate voltage-gated Ca2+ channels in neuronal systems. (nih.gov)
  • Zebrafish have other traits that are helpful to researchers. (nih.gov)
  • The researchers found a way to block key proteins that fuel the growth of new blood vessels in zebrafish. (nih.gov)
  • Zebrafish can help researchers figure out which genes cause human illness. (nih.gov)
  • Researchers are investigating how a reduction in the amount of the SALL4 protein disrupts eye, heart, and limb development in people with Duane-radial ray syndrome and acro-renal-ocular syndrome. (medlineplus.gov)
  • Even though cell proliferation is common in all tissue development, researchers do not fully understand how the amount of histone proteins increases in proportion to the amount of DNA during cell proliferation. (oist.jp)
  • Using zebrafish as a vertebrate animal model, Masai has shown that SLBP is necessary for development to function properly. (oist.jp)
  • 2005). Identification of a new pebp2αA2 isoform from Zebrafish runx2 capable of inducing osteocalcin gene expression in vitro . (up.pt)
  • Many of the proteins in this species have been the subject of studies involving basic embryological development ( EMBRYOLOGY ). (bvsalud.org)
  • Two main mechanisms have been implicated in the pathogenesis of PD as well as of most neurodegenerative diseases: mitochondrial dysfunction and accumulation of toxic proteins. (medscape.com)
  • The first advantage of using zebrafish to study cancer is their transparency, letting us see what's happening inside them with unprecedented detail. (cancer.org)
  • First, their small size, high fertility rate, and rapid development make zebrafish an ideal model for large-scale genetic screens. (frontiersin.org)
  • To study function of these proteins we also use zebrafish as a model system. (nih.gov)
  • We use a zebrafish model to study functions of Olfm1 in development. (nih.gov)
  • Therefore, since the function of ZRSR2 in the hematopoietic system is poorly understood and, to date, there are no animal models available, we decided to use zebrafish as a model to investigate the function of zrsr2 in vivo. (nih.gov)
  • 4. Transcriptome analysis of the zebrafish model of Diamond-Blackfan anemia from RPS19 deficiency via p53-dependent and -independent pathways. (nih.gov)
  • 8. Systematic transcriptome analysis of the zebrafish model of diamond-blackfan anemia induced by RPS24 deficiency. (nih.gov)
  • A fourth model system uses Rohon-Beard primary sensory neurons from Zebrafish to identify how G-protein coupled receptors modulate Ca2+ channels and contribute to mechnosensory function. (nih.gov)
  • Investigating the role of the P97/Vcp segregase in DNA-protein crosslink repair (DPCR) in vivo using the zebrafish // FEBS Open Bio. (irb.hr)
  • Several large-scale mutagenesis screens have been performed in zebrafish, and these screens led to the identification of a series of metal transporters and the generation of several mutagenesis lines, providing an in-depth functional analysis at the system level. (frontiersin.org)
  • Analysis of chromosomal rearrangements induced by postmeiotic mutagenesis with ethylnitrosourea in zebrafish. (nih.gov)
  • Zebrafish organizer development and germ-layer formation require nodal-related signals. (nih.gov)
  • This protein may also be important for the development of nerves that control eye movement and for the formation of the walls (septa) that divide the heart into separate chambers. (medlineplus.gov)
  • To examine the significance of this organizational feature, we studied the functional development of direction-selective (DS) circuits in the tectum of astray mutant zebrafish in which lamination of retinal ganglion cell (RGC) axons is lost. (bath.ac.uk)
  • We don't always know where new findings in zebrafish might lead," Weinstein says. (nih.gov)
  • Masai's findings impact more than just a few zebrafish. (oist.jp)
  • 11. Abnormalities of the large ribosomal subunit protein, Rpl35a, in Diamond-Blackfan anemia. (nih.gov)
  • 13. Cells depleted for RPS19, a protein associated with Diamond Blackfan Anemia, show defects in 18S ribosomal RNA synthesis and small ribosomal subunit production. (nih.gov)
  • SDS-Page: Recombinant Human Pyruvate Dehydrogenase E1-alpha subunit Protein [H00005160-P01] - 12.5% SDS-PAGE Stained with Coomassie Blue. (novusbio.com)
  • Scientists can add genes to zebrafish to make certain cells or tissues glow different colors. (nih.gov)
  • Immunohistochemistry and Western blotting revealed conserved MRP9 protein expression in the bile ducts in human, mouse, and zebrafish. (nih.gov)
  • Zebrafish zrsr2 protein shows 78% similarity to human ZRSR2. (nih.gov)
  • In particular, the Section is interested in the way that protein complexes regulate synaptic function by responding to an influx of calcium ions. (nih.gov)
  • SALL proteins are transcription factors, which means they attach (bind) to specific regions of DNA and help control the activity of particular genes. (medlineplus.gov)
  • It is unclear whether this shortened protein is completely nonfunctional or if it retains some of its function as a transcription factor. (medlineplus.gov)
  • Exposure to DE-71 alters thyroid hormone levels and gene transcription in the hypothalamic-pituitary-thyroid axis of zebrafish larvae. (x-mol.com)
  • Miro and Milton, two proteins implicated in mitochondrial trafficking that associate with PINK1 at the outer mitochondrial membrane, are also implicated in regulation of mitochondria dynamics. (medscape.com)
  • Dynamics of zebrafish somitogenesis. (nih.gov)
  • These 4-D SPIM images provided the visual assessment of zebrafish cardiac mechanics and cardiac flow, which allowed for the quantification of endocardial WSS by Computational Fluid Dynamics (CFD). (escholarship.org)
  • Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors. (novusbio.com)
  • When hair cells die in zebrafish, nearby support cells start replicating. (nih.gov)
  • As a result, cells do not produce any functional protein from one copy of this gene. (medlineplus.gov)
  • As a result, cells produce an abnormally short version of the protein from one copy of this gene. (medlineplus.gov)
  • The Section on Cellular Biophotonics studies how protein complexes are formed and maintained in living cells, and how these complexes regulate cellular functions. (nih.gov)
  • The first involves the construction of a microscope that can be used to study protein complexes in living cells by measuring time resolved fluorescence anisotropy and fluctuations in fluorescence. (nih.gov)
  • Violin plots show distribution of expression levels for WD_REPEATS_REGION domain-containing protein (SMED30025039) in cells (dots) of each of the 12 neoblast clusters. (stowers.org)
  • Expression of WD_REPEATS_REGION domain-containing protein (SMED30025039) in the t-SNE clustered sub-lethally irradiated X1 and X2 cells. (stowers.org)
  • Analysis of Slow-Cycling Variants of the Light-Inducible Nuclear Protein Export System LEXY in Mammalian Cells. (harvard.edu)
  • Some family members, such as latrophilins and gliomedin, are membrane-bound proteins containing the olfactomedin domain in the extracellular N-terminal region, while the intracellular C-terminal domain of these proteins is essential for the transduction of extracellular signals to the intracellular signaling pathway. (nih.gov)
  • ABCC12 encodes multidrug resistance-associated protein 9 (MRP9) that belongs to the adenosine 5'-triphosphate-binding cassette transporter C family with unknown function and no previous implication in liver disease. (nih.gov)
  • The exact function of the SALL4 protein remains unclear. (medlineplus.gov)
  • The third project examines the function of dysferlin, a calcium binding protein implicated in two forms of muscular dystrophy. (nih.gov)
  • In the poster section, Joanna Shisler (University of Illinois at Urbana-Champaign [UIUC], Urbana) reported that the modified virus, Ankara, activates nuclear factor κB through the mitogen-activated protein kinase, extracellular signal-regulated kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway, possibly facilitating the host immune response. (cdc.gov)
  • Using a custom-built OpenSPIM-based light-sheet microscope, image stacks of zebrafish are taken at different angles at different time points, and the samples are monitored for several days. (photometrics.com)
  • Utilizing the estrogen receptor ligand-binding domain for controlled protein translocation to the insoluble fraction. (harvard.edu)
  • In recent decades, zebrafish research studies have led to important insights about cancer, heart disease, and stroke. (nih.gov)
  • This allowed us to also determine the relationship between zebrafish hematocrit and blood viscosity in our studies. (escholarship.org)
  • 2. Ribosomal protein deficiency causes Tp53-independent erythropoiesis failure in zebrafish. (nih.gov)
  • Zebrafish have even helped scientists find and test potential new drugs. (nih.gov)