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SOPHIA OF WISDOM III - ANCIENT MAGIC - ANDRIGEN RECEPTOR
J
THE LIBRARY OF SOPHIA OF WISDOM III
THE SOPHIA OF ALL SOPHIA OF WISDOMS
AKA
CAROLINE E. KENNEDY, JR.______________________
JAN 21, 2007
Androgen receptor
Androgen Receptor
Identifiers
Symbol(s) AR
Entrez
367
OMIM 313700
RefSeq NM_000125
UniProt P10275
Other data
Locus Chr. X q11.2-12
The androgen receptor
is an intracellular steroid receptor of the nuclear receptor super family that specifically binds testosterone and dihydrotestosterone.
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.
Gene
The gene for the androgen receptor is located on the X chromosome at Xq11-12.
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.
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. One of the known target genes of androgen receptor activation is insulin-like growth factor
I (IGF-1). Thus, changes in levels of specific proteins in cells is one way that androgen receptors control cell behavior.
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.
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.
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
External links
Mendelian Inheritance in Man (OMIM) 313700
Androgen receptor gene database
Retrieved from "http://en.wikipedia.org/wiki/Androgen_receptor"
Category: Intracellular receptors
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