Testosterone is converted to 5-alpha-dihydroxytestosterone

Stable Identifier
Reaction [transition]
Homo sapiens
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The conversion of testosterone to the most potent androgen, 5-alpha-dihydrotestosterone (DHT), is catalyzed by the microsomal 5alpha-steroid reductase enzymes, of which there are three reported types in humans to date (SRD5A1-3) (Andersson S and Russell DW, 1990; Andersson S et al, 1991; Uemura M et al, 2008 respectively). These enzymes are expressed in the prostate and other androgen target sites. Defects in SRD5A2 are the cause of pseudovaginal perineoscrotal hypospadias, also known as male pseudohermaphroditism (Anwar R et al, 1997). Corticotropin (Adrenocorticotropic hormone, ACTH) acts through the ACTH receptor called melanocortin receptor type 2 (MC2R) to stimulate steroidogenesis, increasing the production of androgens (McKenna et al, 1997).

Literature References
PubMed ID Title Journal Year
1944596 Deletion of steroid 5 alpha-reductase 2 gene in male pseudohermaphroditism

Andersson, S, Berman, DM, Jenkins, EP, Russell, DW

Nature 1991
9208814 Male pseudohermaphroditism resulting from a novel mutation in the human steroid 5 alpha-reductase type 2 gene (SRD5A2)

Anwar, R, Gilbey, SG, New, JP, Markham, AF

Mol Pathol 1997
9536209 A critical review of the origin and control of adrenal androgens

McKenna, TJ, Fearon, U, Clarke, D, Cunningham, SK

Baillieres Clin Obstet Gynaecol 1997
2339109 Structural and biochemical properties of cloned and expressed human and rat steroid 5 alpha-reductases

Andersson, S, Russell, DW

Proc Natl Acad Sci U S A 1990
17986282 Novel 5 alpha-steroid reductase (SRD5A3, type-3) is overexpressed in hormone-refractory prostate cancer

Uemura, M, Tamura, K, Chung, S, Honma, S, Okuyama, A, Nakamura, Y, Nakagawa, H

Cancer Sci 2008
Participant Of
Catalyst Activity
Catalyst Activity
3-oxo-5-alpha-steroid 4-dehydrogenase activity of SRD5A1-3 [endoplasmic reticulum membrane]
Physical Entity
This event is regulated
Positively by
Orthologous Events
Cross References
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