cytochrome P450 family 46, subfamily A, polypeptide 1, also called cholesterol 24-hydroxylase, and similar cytochrome P450s
CYP46A1 is also called cholesterol 24-hydroxylase (EC 220.127.116.11), CH24H, cholesterol 24-monooxygenase, or cholesterol 24S-hydroxylase. It catalyzes the conversion of cholesterol into 24S-hydroxycholesterol and, to a lesser extent, 25-hydroxycholesterol. CYP46A1 is associated with high-order brain functions; increased expression improves cognition while a reduction leads to a poor cognitive performance. It also plays a role in the pathogenesis or progression of neurodegenerative disorders. CYP46A1 belongs to the large cytochrome P450 (P450, CYP) superfamily of heme-containing proteins that catalyze a variety of oxidative reactions of a large number of structurally different endogenous and exogenous compounds in organisms from all major domains of life. CYPs bind their diverse ligands in a buried, hydrophobic active site, which is accessed through a substrate access channel formed by two flexible helices and their connecting loop.