DHA isomerizes to 4-Androstene3,17-dione Authored: Jassal, B, 2008-10-01 13:18:42 EC Number: 5.3.3.1 Edited: Jassal, B, 2007-04-20 21:09:56 In this two-step reaction catalyzed by 3beta-HSD associated with the endoplasmic reticulum membrane, the 3-hydroxyl group of DHA is oxidized to a keto group and the double bond in the steroid nucleus is then isomerized from the five to the 4 position. 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). Pubmed2243100 Pubmed9536209 Reactome Database ID Release 43193073 Reactome, http://www.reactome.org ReactomeREACT_10056 Reviewed: D'Eustachio, P, 2007-04-20 21:11:21