Protein Domain : 3-oxo-5-alpha-steroid 4-dehydrogenase, C-terminal IPR001104

Type	Domain
Description	3-oxo-5-alpha-steroid 4-dehydrogenases, catalyse the conversion of 3-oxo-5-alpha-steroid + acceptor to 3-oxo-delta(4)-steroid + reduced acceptor. The steroid 5-alpha-reductase enzyme is responsible for the formation of dihydrotestosterone, this hormone promotes the differentiation of male external genitalia and the prostate during foetal development [ ]. In humans mutations in this enzyme can cause a form of male pseudohermaphorditism in which the external genitalia and prostate fail to develop normally. A related steroid reductase enzyme, DET2, is found in plants such as Arabidopsis. Mutations in this enzyme cause defects in light-regulated development []. This domain is present in both type 1 and type 2 [] forms.This domain is also found in polyprenol reductase (SRD5A3; ), which is reduces the alpha-isoprene unit of polyprenol to form dolichol. Dolichol is required for the synthesis of a dolichol-linked monosaccharide and the oligosaccharide precursor used for N-glycosylation [ ].Another enzyme with this domain is very-long-chain enoyl-CoA reductase (TECR; ), which catalyzes the last of the four reactions of the long-chain fatty acids elongation cycle by reducing the trans-2,3-enoyl-CoA fatty acid intermediate to an acyl-CoA that can be further elongated by entering a new cycle of elongation [ ].
Short Name	3-oxo-5_a-steroid_4-DH_C