CYP8B1

CYP8B1 (cytochrome P450, family 8, subfamily B, polypeptide 1) also known as sterol 12-alpha-hydroxylase is a is_associated_with::protein which in humans is encoded by the CYP8B1 is_associated_with::gene.

This gene encodes a member of the is_associated_with::cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are is_associated_with::monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids.

CYP8B1 is an is_associated_with::endoplasmic reticulum membrane protein and catalyzes the conversion of is_associated_with::7 alpha-hydroxy-4-cholesten-3-one into 7-alpha,12-alpha-dihydroxy-4-cholesten-3-one. The balance between these two steroids determines the relative amounts of the two primary is_associated_with::bile acids, is_associated_with::cholic acid and is_associated_with::chenodeoxycholic acid, both of which are secreted in the bile. In the intestine these is_associated_with::bile acids affect the solubility of is_associated_with::cholesterol and other lipids, promoting their absorption.

CYP8B1 is unique among the cytochrome P450 genes in that it is is_associated_with::intronless.