CYP11A1 Antibody #12491

In steroidogenic tissues, such as the adrenal cortex, testis, ovary, and placenta, all steroids are synthesized from the common precursor cholesterol. Two families of steroidogenic enzymes, cytochrome P450 hydroxylase enzymes (CYP) and hydroxysteroid dehydrogenases (HSD), catalyze the production of most steroids. There are six distinct steroid hydroxylases, which are cytochrome P450 enzymes encoded by the steroidogenic CYP gene family (1). The cytochrome P450scc (cholesterol side-chain cleavage enzyme) encoded by CYP11A1 catalyzes the first and rate-limiting step in steroidogenesis, conversion of cholesterol into pregnenolone (2).

CYP11A1, located in the inner membrane of mitochondria, cooperates with two coenzymes, ferredoxin and ferredoxin reductase, to carry out three successive oxidation-reduction reactions of cholesterol (3-5). In the adrenal cortex, testis, and ovary, CYP11A1 expression is regulated by the cAMP-PKA pathway (6), and the transcription factor SF1/NR5A1 has been shown to play a central role in mediating the cAMP signal on the CYP11A1 promoter within steroidogeneic cells of the adrenal cortex and gonads (7). Defects in CYP11A1 are the cause of adrenal insufficiency congenital with 46, XY sex reversal (AICSR), which is a rare disorder that can present as acute adrenal insufficiency in infancy or childhood (8,9).