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SOX1
SOX1 is a gene that encodes a transcription factor with a HMG-box (high mobility group) DNA-binding domain and functions primarily in neurogenesis. SOX1, SOX2 and SOX3, members of the SOX gene family (specifically the SOXB1 group), contain transcription factors related to '' SRY'', the testis-determining factor. SOX1 exerts its importance in its role in development of the central nervous system (neurogenesis) and in particular the development of the eye, where it is functionally redundant with SOX3 and to a lesser degree SOX2, and maintenance of neural progenitor cell identity. SOX1 expression is restricted to the neuroectoderm by proliferating progenitor cells in the tetrapod embryo. The induction of this neuroectoderm occurs upon expression of the SOX1 gene. In ectodermal cells committed to a certain cell fate, SOX1 has shown to be one of the earliest transcription factors expressed. In particular, SOX1 is first detected in the late head fold stage. Clinical significance and ... [...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 acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Mobility Group
High-Mobility Group or HMG is a group of chromosomal proteins that are involved in the regulation of DNA-dependent processes such as transcription, replication, recombination, and DNA repair. Families The HMG proteins are subdivided into 3 superfamilies each containing a characteristic functional domain: * HMGA – contains an AT-hook domain ** HMGA1 ** HMGA2 * HMGB – contains a HMG-box domain ** HMGB1 ** HMGB2 ** HMGB3 ** HMGB4 * HMGN – contains a nucleosomal binding domain ** HMGN1 ** HMGN2 ** HMGN3 ** HMGN4 ** HMGN5 Proteins containing any of these embedded in their sequence are known as HMG motif proteins. HMG-box proteins are found in a variety of eukaryotic organisms. They were originally isolated from mammalian cells, and named according to their electrophoretic mobility in polyacrylamide gels. Other families with HMG-box domain * SOX gene family ** Sex-Determining Region Y Protein ** SOX1, SOX2, etc. * TCF/LEF family (T cell factor/lymphoid enhancer factor fa ... [...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 of 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 expressed in the desired 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 up to 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 (as an activator), or blocking (as a repressor) the recruitment of RNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuroectoderm
Neuroectoderm (or neural ectoderm or neural tube epithelium) consists of cells derived from ectoderm. Formation of the neuroectoderm is first step in the development of the nervous system. The neuroectoderm receives bone morphogenetic protein-inhibiting signals from proteins such as noggin, which leads to the development of the nervous system from this tissue. Histologically, these cells are classified as pseudostratified columnar cells. After recruitment from the ectoderm, the neuroectoderm undergoes three stages of development: transformation into the neural plate, transformation into the neural groove (with associated neural folds), and transformation into the neural tube. After formation of the tube, the brain forms into three sections; the hindbrain, the midbrain, and the forebrain. The types of neuroectoderm include: *Neural crest ** pigment cells in the skin **ganglia of the autonomic nervous system **dorsal root ganglia. **facial cartilage ** aorticopulmonary septum of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurogenesis
Neurogenesis is the process by which nervous system cells, the neurons, are produced by neural stem cells (NSCs). It occurs in all species of animals except the porifera (sponges) and placozoans. Types of NSCs include neuroepithelial cells (NECs), radial glial cells (RGCs), basal progenitors (BPs), intermediate neuronal precursors (INPs), subventricular zone astrocytes, and subgranular zone radial astrocytes, among others. Neurogenesis is most active during embryonic development and is responsible for producing all the various types of neurons of the organism, but it continues throughout adult life in a variety of organisms. Once born, neurons do not divide (see mitosis), and many will live the lifespan of the animal. Neurogenesis in mammals Developmental neurogenesis During embryonic development, the mammalian central nervous system (CNS; brain and spinal cord) is derived from the neural tube, which contains NSCs that will later generate neurons. However, neurogenesis does ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epilepsy
Epilepsy is a group of non-communicable neurological disorders characterized by recurrent epileptic seizures. Epileptic seizures can vary from brief and nearly undetectable periods to long periods of vigorous shaking due to abnormal electrical activity in the brain. These episodes can result in physical injuries, either directly such as broken bones or through causing accidents. In epilepsy, seizures tend to recur and may have no immediate underlying cause. Isolated seizures that are provoked by a specific cause such as poisoning are not deemed to represent epilepsy. People with epilepsy may be treated differently in various areas of the world and experience varying degrees of social stigma due to the alarming nature of their symptoms. The underlying mechanism of epileptic seizures is excessive and abnormal neuronal activity in the cortex of the brain which can be observed in the electroencephalogram (EEG) of an individual. The reason this occurs in most cases of epilepsy is u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Striatum
The striatum, or corpus striatum (also called the striate nucleus), is a nucleus (a cluster of neurons) in the subcortical basal ganglia of the forebrain. The striatum is a critical component of the motor and reward systems; receives glutamatergic and dopaminergic inputs from different sources; and serves as the primary input to the rest of the basal ganglia. Functionally, the striatum coordinates multiple aspects of cognition, including both motor and action planning, decision-making, motivation, reinforcement, and reward perception. The striatum is made up of the caudate nucleus and the lentiform nucleus. The lentiform nucleus is made up of the larger putamen, and the smaller globus pallidus. Strictly speaking the globus pallidus is part of the striatum. It is common practice, however, to implicitly exclude the globus pallidus when referring to striatal structures. In primates, the striatum is divided into a ventral striatum, and a dorsal striatum, subdivisions that are base ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ectodermal
The ectoderm is one of the three primary germ layers formed in early embryonic development. It is the outermost layer, and is superficial to the mesoderm (the middle layer) and endoderm (the innermost layer). It emerges and originates from the outer layer of germ cells. The word ectoderm comes from the Greek ''ektos'' meaning "outside", and ''derma'' meaning "skin".Gilbert, Scott F. Developmental Biology. 9th ed. Sunderland, MA: Sinauer Associates, 2010: 333-370. Print. Generally speaking, the ectoderm differentiates to form epithelial and neural tissues (spinal cord, peripheral nerves and brain). This includes the skin, linings of the mouth, anus, nostrils, sweat glands, hair and nails, and tooth enamel. Other types of epithelium are derived from the endoderm. In vertebrate embryos, the ectoderm can be divided into two parts: the dorsal surface ectoderm also known as the external ectoderm, and the neural plate, which invaginates to form the neural tube and neural crest. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrapod
Tetrapods (; ) are four-limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant and extinct amphibians, sauropsids ( reptiles, including dinosaurs and therefore birds) and synapsids (pelycosaurs, extinct therapsids and all extant mammals). Tetrapods evolved from a clade of primitive semiaquatic animals known as the Tetrapodomorpha which, in turn, evolved from ancient lobe-finned fish (sarcopterygians) around 390 million years ago in the Middle Devonian period; their forms were transitional between lobe-finned fishes and true four-limbed tetrapods. Limbed vertebrates (tetrapods in the broad sense of the word) are first known from Middle Devonian trackways, and body fossils became common near the end of the Late Devonian but these were all aquatic. The first crown-tetrapods (last common ancestors of extant tetrapods capable of terrestrial locomotion) appeared by the very early Carboniferous, 350 million years ago. The specific aquatic ancestors ... [...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 and spinal cord. 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 bilaterally symmetric and triploblastic animals—that is, all multicellular animals except sponges and diploblasts. It is a structure composed of nervous tissue positioned along the 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 (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 cord are both enclosed in the meninges. The meninges provide a barrier to chemicals dissolv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Development Of The Eye
Eye formation in the human embryo begins at approximately three weeks into embryonic development and continues through the tenth week.Ort, D., David, H."Development of the Eye" Retrieved 22 April 2015. Cells from both the mesodermal and the ectodermal tissues contribute to the formation of the eye. Specifically, the eye is derived from the neuroepithelium, surface ectoderm, and the extracellular mesenchyme which consists of both the neural crest and mesoderm. Neuroepithelium forms the retina, ciliary body, iris, and optic nerves. Surface ectoderm forms the lens, corneal epithelium and eyelid. The extracellular mesenchyme forms the sclera, the corneal endothelium and stroma, blood vessels, muscles, and vitreous. The eye begins to develop as a pair of optic vesicles on each side of the forebrain at the end of the 4th week of pregnancy. Optic vesicles are outgrowings of the brain which make contact with the surface ectoderm and this contact induces changes necessary for f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMG-box
In molecular biology, the HMG-box (high mobility group box) is a protein domain which is involved in DNA binding. Structure The structure of the HMG-box domain contains three alpha helices separated by loops (see figure to the right). Function HMG-box containing proteins only bind non- B-type DNA conformations (kinked or unwound) with high affinity. HMG-box domains are found in some high mobility group proteins, which are involved in the regulation of DNA-dependent processes such as transcription, replication, and DNA repair, all of which require changing the conformation of chromatin Chromatin is a complex of DNA and protein found in eukaryotic cells. The primary function is to package long DNA molecules into more compact, denser structures. This prevents the strands from becoming tangled and also plays important roles in r .... The single and the double box HMG proteins alter DNA architecture by inducing bends upon binding.D. Murugesapillai ''et al''Single-molecule stud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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