CYP27B1
CYP27B1 (cytochrome P450 family 27 subfamily B member 1, also known as P450c1, CYP1, VDD1 and PDDR) is a mitochondrial cytochrome P450 monooxygenase. It catalyses the rate-limiting activation of vitamin D in the kidney, producing the hormonally active form, calcitriol. Browse Assay Genie's current range of CYP27B1 research reagents below, or read on for the biology behind the target.
CYP27B1 is a cytochrome P450 monooxygenase involved in vitamin D metabolism and in calcium and phosphorus homeostasis. It catalyses the rate-limiting step in vitamin D activation in the kidney: the hydroxylation of 25-hydroxyvitamin D3 (calcidiol) at the C1alpha-position to form 1alpha,25-dihydroxyvitamin D3 (calcitriol). Calcitriol is the hormonally active form of vitamin D3 and acts through the vitamin D receptor (VDR). The enzyme is also active on 25-hydroxyvitamin D2.
The enzyme has 1alpha-hydroxylase activity on intermediates of the CYP24A1-mediated inactivation pathway. It converts 24R,25-dihydroxyvitamin D3 (secalciferol) to 1alpha,24,25-trihydroxyvitamin D3, which is an active VDR ligand. Mechanistically, it uses molecular oxygen, inserting one oxygen atom into the substrate and reducing the second to water. The two electrons come from NADPH via FDXR (adrenodoxin reductase) and FDX1 (adrenodoxin). By setting the level of biologically active vitamin D, CYP27B1 plays an important role in calcium homeostasis.
The CYP27B1 gene encodes a member of the cytochrome P450 superfamily. These monooxygenases catalyse many reactions in drug metabolism and in the synthesis of cholesterol, steroids and other lipids. HGNC places the gene in the cytochrome P450 family 27 group, and the protein localises to the inner mitochondrial membrane. Mutations in the gene can result in vitamin D-dependent rickets type I, which explains the alias VDD1. Mouse and rat both carry a Cyp27b1 ortholog, so the enzyme can be studied in common rodent models.
CYP27B1 converts calcidiol to calcitriol, the rate-limiting activation step, so it is central to studies of how active vitamin D is produced.
By regulating levels of biologically active vitamin D, the enzyme contributes to calcium homeostasis and is relevant to mineral balance research.
Mutations in the CYP27B1 gene can cause vitamin D-dependent rickets type I, making it a key gene in this disorder.
This mitochondrial monooxygenase draws electrons from NADPH through FDXR and FDX1, providing a model for steroid-type P450 electron transfer.
CYP27B1 is a mitochondrial cytochrome P450 monooxygenase that hydroxylates 25-hydroxyvitamin D3 at the C1alpha-position. This forms calcitriol, the active vitamin D3 hormone that signals through the vitamin D receptor. It is the rate-limiting activation step in the kidney and supports calcium homeostasis.
CYP27B1 is also called P450c1, CYP1, VDD1 and PDDR. The UniProt name is 25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial. Older HGNC names describe it as cytochrome P450, subfamily XXVIIB, polypeptide 1. Its EC number is 1.14.15.18.
Mutations in the CYP27B1 gene can result in vitamin D-dependent rickets type I. Mouse and rat each have a Cyp27b1 ortholog. When working with a species other than human, check the datasheet of any product for its validated reactivity.
Other cytochrome P450 enzymes, including vitamin D, steroid and sterol metabolism family members with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt O15528; product specifications from Assay Genie datasheets.