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Neural Fold
The neural fold is a structure that arises during neurulation in the embryonic development of both birds and mammals among other organisms. This structure is associated with primary neurulation, meaning that it forms by the coming together of tissue layers, rather than a clustering, and subsequent hollowing out, of individual cells (known as secondary neurulation). In humans, the neural folds are responsible for the formation of the anterior end of the neural tube. The neural folds are derived from the neural plate, a preliminary structure consisting of elongated ectoderm cells. The folds give rise to neural crest cells, as well as bringing about the formation of the neural tube. Development In the embryo, the formation of the neural folds originates from the area where the neural plate and the surrounding ectoderm converge. This region of the embryo is formed after gastrulation, and consists of epithelial tissue. Here, the epithelial cells elongate by means of microtubule pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Plate
In embryology, the neural plate is a key Development of the human body, developmental structure that serves as the basis for the nervous system. Cranial to the primitive node of the embryonic primitive streak, Ectoderm, ectodermal tissue thickens and flattens to become the neural plate. The region anterior to the primitive node can be generally referred to as the neural plate. Cells take on a columnar appearance in the process as they continue to lengthen and narrow. The ends of the neural plate, known as the neural folds, push the ends of the plate up and together, folding into the neural tube, a structure critical to brain and spinal cord development. This process as a whole is termed primary neurulation. Signaling proteins are also important in neural plate development, and aid in Cellular differentiation, differentiating the tissue destined to become the neural plate. Examples of such proteins include bone morphogenetic proteins and cadherins. Expression of these proteins i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Fold
The neural fold is a structure that arises during neurulation in the embryonic development of both birds and mammals among other organisms. This structure is associated with primary neurulation, meaning that it forms by the coming together of tissue layers, rather than a clustering, and subsequent hollowing out, of individual cells (known as secondary neurulation). In humans, the neural folds are responsible for the formation of the anterior end of the neural tube. The neural folds are derived from the neural plate, a preliminary structure consisting of elongated ectoderm cells. The folds give rise to neural crest cells, as well as bringing about the formation of the neural tube. Development In the embryo, the formation of the neural folds originates from the area where the neural plate and the surrounding ectoderm converge. This region of the embryo is formed after gastrulation, and consists of epithelial tissue. Here, the epithelial cells elongate by means of microtubule pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesenchymal
Mesenchyme () is a type of loosely organized animal embryonic connective tissue of undifferentiated cells that give rise to most tissues, such as skin, blood, or bone. The interactions between mesenchyme and epithelium help to form nearly every organ in the developing embryo. Vertebrates Structure Mesenchyme is characterized morphologically by a prominent ground substance matrix containing a loose aggregate of reticular fibers and unspecialized mesenchymal stem cells. Mesenchymal cells can migrate easily (in contrast to epithelial cells, which lack mobility, are organized into closely adherent sheets, and are polarized in an apical- basal orientation). Development The mesenchyme originates from the mesoderm. From the mesoderm, the mesenchyme appears as an embryologically primitive "soup". This "soup" exists as a combination of the mesenchymal cells plus serous fluid plus the many different tissue proteins. Serous fluid is typically stocked with the many serous elements, su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Nervous System
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all parts of the bodies of bilateria, bilaterally symmetric and triploblastic animals—that is, all multicellular animals except sponges and Coelenterata, diploblasts. It is a structure composed of nervous tissue positioned along the Anatomical_terms_of_location#Rostral,_cranial,_and_caudal, rostral (nose end) to caudal (tail end) axis of the body and may have an enlarged section at the rostral end which is a brain. Only arthropods, cephalopods and vertebrates have a true brain, though precursor structures exist in onychophorans, gastropods and lancelets. The rest of this article exclusively discusses the vertebrate central nervous system, which is radically distinct from all other animals. Overview In vertebrates, the brain and spinal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadherin
Cadherins (named for "calcium-dependent adhesion") are cell adhesion molecules important in forming adherens junctions that let cells adhere to each other. Cadherins are a class of type-1 transmembrane proteins, and they depend on calcium (Ca2+) ions to function, hence their name. Cell-cell adhesion is mediated by extracellular cadherin domains, whereas the Cadherin cytoplasmic region, intracellular cytoplasmic tail associates with numerous adaptors and signaling proteins, collectively referred to as the cadherin adhesome. Background The cadherin family is essential in maintaining cell-cell contact and regulating cytoskeletal complexes. The cadherin superfamily includes cadherins, protocadherins, desmogleins, desmocollins, and more. In structure, they share ''cadherin repeats'', which are the extracellular Ca2+-binding domains. There are multiple classes of cadherin molecules, each designated with a prefix for tissues with which it associates. Classical cadherins maintain the ton ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonic Hedgehog
Sonic hedgehog protein (SHH) is a major signaling molecule of embryonic development in humans and animals, encoded by the ''SHH'' gene. This signaling molecule is key in regulating embryonic morphogenesis in all animals. SHH controls organogenesis and the organization of the central nervous system, limbs, digits and many other parts of the body. Sonic hedgehog is a morphogen that patterns the developing embryo using a concentration gradient characterized by the French flag model. This model has a non-uniform distribution of SHH molecules which governs different cell fates according to concentration. Mutations in this gene can cause holoprosencephaly, a failure of splitting in the cerebral hemispheres, as demonstrated in an experiment using SHH knock-out mice in which the forebrain midline failed to develop and instead only a single fused telencephalic vesicle resulted. Sonic hedgehog still plays a role in differentiation, proliferation, and maintenance of adult tissues. Abno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Factor
In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription (genetics), transcription of genetics, genetic information from DNA to messenger RNA, by binding to a specific DNA sequence. The function of TFs is to regulate—turn on and off—genes in order to make sure that they are Gene expression, expressed in the desired Cell (biology), cells at the right time and in the right amount throughout the life of the cell and the organism. Groups of TFs function in a coordinated fashion to direct cell division, cell growth, and cell death throughout life; cell migration and organization (body plan) during embryonic development; and intermittently in response to signals from outside the cell, such as a hormone. There are approximately 1600 TFs in the human genome. Transcription factors are members of the proteome as well as regulome. TFs work alone or with other proteins in a complex, by promoting (a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SOX Gene Family
''SOX'' genes ('' SRY''-related HMG-box genes) encode a family of transcription factors that bind to the minor groove in DNA, and belong to a super-family of genes characterized by a homologous sequence called the HMG-box (for high mobility group). This HMG box is a DNA binding domain that is highly conserved throughout eukaryotic species. Homologues have been identified in insects, nematodes, amphibians, reptiles, birds and a range of mammals. However, HMG boxes can be very diverse in nature, with only a few amino acids being conserved between species. Sox genes are defined as containing the HMG box of a gene involved in sex determination called '' SRY'', which resides on the Y-chromosome. There are 20 SOX genes present in humans and mice, and 8 present in Drosophila. Almost all Sox genes show at least 50% amino acid similarity with the HMG box in Sry. The family is divided into subgroups according to homology within the HMG domain and other structural motifs, as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chordin
Chordin (from Greek χορδή, string, catgut) is a protein with a prominent role in dorsal–ventral patterning during early embryonic development. In humans it is encoded for by the ''CHRD'' gene. History Chordin was originally identified in the African clawed frog (''Xenopus laevis'') in the laboratory of Edward M. De Robertis as a key developmental protein that dorsalizes early vertebrate embryonic tissues. It was first hypothesized that chordin plays a role in the dorsal homeobox genes in Spemann's organizer. The chordin gene was discovered through its activation following use of gsc ( goosecoid) and Xnot mRNA injections. The discoverers of chordin concluded that it is expressed in embryo regions where gsc and Xnot were also expressed, which included the prechordal plate, the notochord, and the chordoneural hinge. The expression of the gene in these regions led to the name chordin. Initial functions of chordin were thought to include recruitment of neighboring cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noggin (protein)
Noggin, also known as NOG, is a protein that is involved in the development of many Tissue (biology), body tissues, including Nervous tissue, nerve tissue, Skeletal muscle, muscles, and bones. In humans, noggin is encoded by the ''NOG'' gene. The Protein primary structure, amino acid sequence of human noggin is highly homologous to that of rat, mouse, and ''Xenopus'' (an aquatic frog genus). Noggin is an inhibitor of several Bone morphogenetic protein, bone morphogenetic proteins (BMPs): it inhibits at least Bone morphogenetic protein 2, BMP2, Bone morphogenetic protein 4, 4, Bone morphogenetic protein 5, 5, Bone morphogenetic protein 6, 6, Bone morphogenetic protein 7, 7, GDF6, 13, and GDF5, 14. The protein's name, which is a slang English-language word for "head", was coined in reference to its ability to produce embryos with large heads when exposed at high concentrations. Function Noggin is a Cell signaling, signaling molecule that plays an important role in promoting som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Morphogenetic Proteins
Bone morphogenetic proteins (BMPs) are a group of growth factors also known as cytokines and as metabologens. Professor Marshall R. Urist, Marshall Urist and Professor A. Hari Reddi, Hari Reddi discovered their ability to induce the formation of bone and cartilage, BMPs are now considered to constitute a group of pivotal morphogenetic signals, orchestrating tissue architecture throughout the body. The important functioning of BMP signals in physiology is emphasized by the multitude of roles for dysregulated BMP signalling in pathological processes. Cancerous disease often involves misregulation of the BMP signalling system. Absence of BMP signalling is, for instance, an important factor in the progression of colon cancer, and conversely, overactivation of BMP signalling following reflux-induced esophagitis provokes Barrett's esophagus and is thus instrumental in the development of Esophageal cancer#Adenocarcinoma, esophageal adenocarcinoma. Recombinant human BMPs (rhBMPs) are used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
