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SOX9
Transcription factor SOX-9 is a protein that in humans is encoded by the ''SOX9'' gene. Function SOX-9 recognizes the sequence CCTTGAG along with other members of the HMG-box class DNA-binding domain, DNA-binding proteins. It is expressed by proliferating but not hypertrophic chondrocytes that is essential for differentiation of precursor cells into chondrocytes and, with steroidogenic factor 1, regulates transcription of the anti-Müllerian hormone (Anti-Müllerian hormone, AMH) gene. SOX-9 also plays a pivotal role in male sexual development; by working with Sf1, SOX-9 can produce AMH in Sertoli cells to inhibit the creation of a female reproductive system. It also interacts with a few other genes to promote the development of male sexual organs. The process starts when the transcription factor testis determining factor (encoded by the sex-determining region SRY of the Y chromosome) activates SOX-9 activity by binding to an enhancer (genetics), enhancer sequence Upstream and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testis Determining Factor
Sex-determining region Y protein (SRY), or testis-determining factor (TDF), is a DNA-binding protein (also known as gene-regulatory protein/transcription factor) encoded by the ''SRY'' gene that is responsible for the initiation of male sex determination in therian mammals ( placentals and marsupials). ''SRY'' is an intronless sex-determining gene on the Y chromosome. Mutations in this gene lead to a range of disorders of sex development with varying effects on an individual's phenotype and genotype. SRY is a member of the SOX (SRY-like box) gene family of DNA-binding proteins. When complexed with the steroidogenic factor 1 (SF-1) protein, SRY acts as a transcription factor that causes upregulation of other transcription factors, most importantly SOX9. Its expression causes the development of primary sex cords, which later develop into seminiferous tubules. These cords form in the central part of the yet-undifferentiated gonad, turning it into a testis. The now-induc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campomelic Dysplasia
Campomelic dysplasia (CMD) is a genetic disorder characterized by bowing of the long bones and many other skeletal and extraskeletal features. It can be lethal in the neonatal period due to respiratory insufficiency, but the severity of the disease is variable, and a significant proportion of patients survive into adulthood. The name is derived from the Greek roots ''campo'' (or ''campto''), meaning bent, and ''melia'', meaning limb. An unusual aspect of the disease is that up to two-thirds of affected 46,XY genotypic males display a range of disorders of sexual development (DSD) and genital ambiguities or may even develop as normal phenotypic females as in complete 46 XY sex reversal. An atypical form of the disease with absence of bowed limbs is called, prosaically, acampomelic campomelic dysplasia (ACD) and is found in about 10% of patients, particularly those surviving the neonatal period. Signs and symptoms While the definitive presentation of the disease is a patient ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FGF9
Glia-activating factor is a protein that in humans is encoded by the ''FGF9'' gene. Function The protein encoded by this gene is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. This protein was isolated as a secreted factor that exhibits a growth-stimulating effect on cultured glial cells. In nervous system, this protein is produced mainly by neurons and may be important for glial cell development. Expression of the mouse homolog of this gene was found to be dependent on Sonic hedgehog (Shh) signaling. Mice lacking the homolog gene displayed a male-to-female sex reversal phenotype, which suggested a role in testicular embryogenesis. This gene is involved in the patterning of sex determination, lung development, and skeletal development. Sex de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroidogenic Factor 1
The steroidogenic factor 1 (SF-1) protein is a transcription factor involved in sex determination by controlling the activity of genes related to the reproductive glands or gonads and adrenal glands. This protein is encoded by the ''NR5A1'' gene, a member of the nuclear receptor subfamily, located on the long arm of chromosome 9 at position 33.3. It was originally identified as a regulator of genes encoding cytochrome P450 steroid hydroxylases, however, further roles in endocrine function have since been discovered. Structure The ''NR5A1'' gene encodes a 461-amino acid protein that shares several conserved domains consistent with members of the nuclear receptor subfamily. The N-terminal domain includes two zinc fingers and is responsible for DNA binding via specific recognition of target sequences. Variations of AGGTCA DNA motifs allows SF-1 to interact with the major groove of the DNA helix and monomerically bind. Following binding, trans-activation of target genes depends on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PGD2
Prostaglandin D2 (or PGD2) is a prostaglandin that binds to the receptor PTGDR (DP1), as well as CRTH2 (DP2). It is a major prostaglandin produced by mast cells – recruits Th2 cells, eosinophils, and basophils. In mammalian organs, large amounts of PGD2 are found only in the brain and in mast cells. It is critical to development of allergic diseases such as asthma. Research carried out in 1989' found PGD2 is the primary mediator of vasodilation (the "niacin flush") after ingestion of niacin (nicotinic acid). A 2012 research paper indicates a causal link between elevated levels of localized PGD2 and hair growth inhibition. Applied topically, the researchers found PGD2 prevents hair growth, and mice that were genetically inclined to produce higher levels of PGD2 had inhibited hair growth. The researchers also found PGD2 levels were much higher in balding scalp tissue than nonbalding scalp tissue, through increased levels of prostaglandin D2 synthase. The paper suggested th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondrocytes
Chondrocytes (, ) are the only cells found in healthy cartilage. They produce and maintain the cartilaginous matrix, which consists mainly of collagen and proteoglycans. Although the word '' chondroblast'' is commonly used to describe an immature chondrocyte, the term is imprecise, since the progenitor of chondrocytes (which are mesenchymal stem cells) can differentiate into various cell types, including osteoblasts. Development From least- to terminally-differentiated, the chondrocytic lineage is: # Colony-forming unit-fibroblast # Mesenchymal stem cell / marrow stromal cell # Chondrocyte # Hypertrophic chondrocyte Mesenchymal (mesoderm origin) stem cells are undifferentiated, meaning they can differentiate into a variety of generative cells commonly known as osteochondrogenic (or osteogenic, chondrogenic, osteoprogenitor, etc.) cells. When referring to bone, or in this case cartilage, the originally undifferentiated mesenchymal stem cells lose their pluripotency, proliferat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-Müllerian Hormone
Anti-Müllerian hormone (AMH), also known as Müllerian-inhibiting hormone (MIH), is a glycoprotein hormone structurally related to Activin and inhibin, inhibin and activin from the transforming growth factor beta superfamily, whose key roles are in growth differentiation and folliculogenesis. In humans, it is encoded by the gene, on chromosome 19p13.3, while its Receptor (biochemistry), receptor is encoded by the gene on chromosome 12. AMH is activated by SOX9 in the Sertoli cells of the male fetus. Its expression inhibits the development of the female reproductive tract, or Müllerian ducts (paramesonephric ducts), in the male embryo, thereby arresting the development of fallopian tubes, uterus, and upper vagina. ''AMH'' expression is critical to sex differentiation at a specific time during fetal development, and appears to be tightly regulated by nuclear receptor Steroidogenic factor 1, SF-1, GATA transcription factor, transcription GATA factors, sex-reversal gene DAX1, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sertoli Cell
Sertoli cells are a type of sustentacular "nurse" cell found in human testes which contribute to the process of spermatogenesis (the production of sperm) as a structural component of the seminiferous tubules. They are activated by follicle-stimulating hormone (FSH) secreted by the adenohypophysis and express FSH receptor on their membranes. History Sertoli cells are named after Enrico Sertoli, an Italian physiologist who discovered them while studying medicine at the University of Pavia, Italy. He published a description of his eponymous cell in 1865. The cell was discovered by Sertoli with a Belthle microscope which had been purchased in 1862. In the 1865 publication, his first description used the terms "tree-like cell" or "stringy cell"; most importantly, he referred to these as "mother cells". Other scientists later used Enrico's family name to label these cells in publications, beginning in 1888. As of 2006, two textbooks that are devoted specifically to the Sertoli cell ... [...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). This 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, except under extraordinary and usually pathogenic circumstances. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gliogenesis
Gliogenesis is the generation of non-neuronal glia populations derived from multipotent neural stem cells. Overview Gliogenesis results in the formation of non-neuronal glia populations from neuronal cells. In this capacity, glial cells provide multiple functions to both the central nervous system (CNS) and the peripheral nervous system (PNS). Subsequent differentiation of glial cell populations results in function-specialized glial lineages. Glial cell-derived astrocytes are specialized lineages responsible for modulating the chemical environment by altering ion gradients and neurotransmitter transduction. Similarly derived, oligodendrocytes produce myelin, which insulates axons to facilitate electric signal transduction. Finally, microglial cells are derived from glial precursors and carry out macrophage-like properties to remove cellular and foreign debris within the central nervous system ref. Functions of glial-derived cell lineages are reviewed by Baumann and Hauw. Gliogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SiRNA
Small interfering RNA (siRNA), sometimes known as short interfering RNA or silencing RNA, is a class of double-stranded non-coding RNA molecules, typically 20–24 base pairs in length, similar to microRNA (miRNA), and operating within the RNA interference (RNAi) pathway. It interferes with the expression of specific genes with complementary nucleotide sequences by degrading messenger RNA (mRNA) after transcription, preventing translation. Text was copied from this source, which is available under Creative Commons Attribution 4.0 International License It was discovered in 1998 by Andrew Fire at the Carnegie Institution for Science in Washington, D.C. and Craig Mello at the University of Massachusetts in Worcester. Structure Naturally occurring siRNAs have a well-defined structure that is a short (usually 20 to 24- bp) double-stranded RNA (dsRNA) with phosphorylated 5' ends and hydroxylated 3' ends with two overhanging nucleotides. The Dicer enzyme catalyzes prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RTL3
Retrotransposon Gag like 3 is a protein that in humans is encoded by the RTL3 gene. Function This gene is a member of a family of gag-related retrotransposon genes. These genes appear to have lost the ability to retrotranspose; however, their open reading frame In molecular biology, reading frames are defined as spans of DNA sequence between the start and stop codons. Usually, this is considered within a studied region of a prokaryotic DNA sequence, where only one of the six possible reading frames ...s have remained intact, which may indicate that these genes have acquired new functions in the cell. Retrotransposon gag-like-3 (RTL3/ZCCHC5/MART3) is one of eleven Sushi-like neogenes identified in the human genome7 RTL3 encodes a 53 kDa protein with a nucleic acid-binding domain (CX2CX4HX4C), gag-like region within the open reading frame and an ssDNA/RNA-binding homeobox-associated leucine zipper motif. It has been reported that RTL3 and SOX-9 co-regulate the expressio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
