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The androgen receptor is an intracellular steroid receptor that specifically binds testosterone and dihydrotestosterone. Steroid hormone receptors are generally intracellular receptors that perform signal transduction for steroid hormones. ...
Testosterone is a steroid hormone from the androgen group. ...
Dihydrotestosterone (DHT) is a biologically active metabolite of the hormone testosterone, formed primarily in the prostate gland, testes, hair follicles, and adrenal glands by the enzyme 5α-reductase by means of reducing the Δ4,5 double-bond. ...
Structure Like all steroid receptors, the androgen receptor has several functional domains. Androgen receptors have a DNA binding domain, a hinge section, and the hormone binding domain. There is only one active form of the androgen receptor. Smaller forms represent proteolytic fragments that are not considered physiologically relevant. The androgen receptor is most closely related to the progesterone receptor, and progestins in higher dosages can block the androgen receptor. Within a protein, a structural domain (domain) is an element of overall structure that is self-stabilizing and often folds independently of the rest of the protein chain. ...
The progesterone receptor is an intracellular steroid receptor that specifically binds progesterone. ...
Gene The gene for the androgen receptor is located on the X chromosome at Xq11-12. The X chromosome is one of the two sex chromosomes in mammals (the other is the Y chromosome). ...
Function In some cell types testosterone interacts directly with androgen receptors while in others testosterone is converted by 5-alpha-reductase to dihydrotestosterone, an even more potent agonist for androgen receptor activation. Examples are derivatives of the Wolffian duct for the former, and derivatives of the urogenital sinus, the urogenital tubercle, and hair follicles for the latter. 5-alpha reductase is an enzyme (EC 1. ...
Agonists An agonist is a substance that binds to a receptor and triggers a response in the cell. ...
The Wolffian duct (also known as archinephric duct, Leydigs duct, and the mesonephric duct) is an paired organ found in mammals including humans during embryogenesis. ...
The urogenital sinus (also known as the persistent cloaca) is a part of the human body while it is an embryo. ...
A hair follicle is part of the skin that grows hair by packing old cells together. ...
The first known mechanism of action for androgen receptors was direct regulation of gene transcription. After androgen binds to an androgen receptor, restructuring with dimerization follows and the activated receptor complex enters the nucleus and binds to DNA. Androgen receptors interact with other proteins in the nucleus so as to cause alterations in gene transcription. Often the change in transcription is an activation resulting in formation of more messenger RNA that interacts with ribosomes to produce specific proteins. Thus, changes in levels of specific proteins in cells is one way that androgen receptors control cell behavior. In molecular biology, a transcription factor is a protein that binds DNA at a specific promoter or enhancer region or site, where it regulates transcription. ...
Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates by binding to androgen receptors. ...
In biochemistry, an enzyme or other protein is allosteric if its activity or efficiency changes in response to the binding of an effector molecule at a so-called allosteric site. ...
Sucrose, or common table sugar, is composed of glucose and fructose. ...
The general structure of a section of DNA Deoxyribonucleic acid (DNA) is a nucleic acid —usually in the form of a double helix— that contains the genetic instructions specifying the biological development of all cellular forms of life, and most viruses. ...
This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ...
Transcription is the process through which a DNA sequence is enzymatically copied by an RNA polymerase to produce a complementary RNA. Or, in other words, the transfer of genetic information from DNA into RNA. In the case of protein-encoding DNA, transcription is the beginning of the process that ultimately...
The life cycle of an mRNA in a eukaryotic cell. ...
Figure 1: Ribosome structure indicating small subunit (A) and large subunit (B). ...
More recently, androgen recptors have been shown to have a second mode of action. As has been also found for other steroid hormone receptors such as estrogen receptors, androgen receptors can have actions that are independent of their interactions with DNA[1]. Androgen receptors interact with certain signal transduction proteins in the cytoplasm. Androgen binding to cytoplasmic androgen receptors can cause rapid changes in cell function independent of changes in gene transcription, such as changes in ion transport. Regulation of signal transduction pathways by cytoplasmic androgen receptors can indirectly lead to changes in gene transcription, for example, by leading to phosphorylation of other transcription factors. The estrogen receptor is a receptor for estradiol (the main endogenous estrogen); it is located intracellularly, in parallel with other steroid hormone receptors. ...
In biology, signal transduction is any process by which a cell converts one kind of signal or stimulus into another. ...
Another, unrelated ion channeling process is part of ion implantation. ...
AR deficiencies The androgen insensitivity syndrome, formerly known as testicular feminization, is caused by a mutation of the Androgen Receptor gene located on the X chromosome (locus:Xq11-Xq12). The androgen receptor seems to affect neuron physiology and is defective in Kennedy disease. Androgen insensitivity syndrome (AIS) is a set of disorders of sexual differentiation that results from mutations of the gene encoding the androgen receptor. ...
Kennedy disease (KD) or X-linked spinal-bulbar muscle atrophy is a neuromuscular disease associated with mutations of the androgen receptor (AR). ...
Reference - ↑ "Testosterone activates mitogen-activated protein kinase and the cAMP response element binding protein transcription factor in Sertoli cells" by Charity Fix, Cynthia Jordan, Patricia Cano and William H. Walker in Proc Natl Acad Sci U S A (2004) volume 101 pages 10919-10924.
- Speroff L, Glass RH, Kase NG: Clinical Gynecologic Endocrinology and Infertility. Sixth Ed. Lippincott Williams & Wilkins, Baltimore,MD, 1999.
See also Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates by binding to androgen receptors. ...
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