NADPH dependent cytochrome P450 reductase (CPR, P450R, POR, CYPOR)

Function

• reduces cytochrome P450 & heme oxygenase
• required for electron transfer from NADP to cytochrome P450 in microsomes
• can also provide electron transfer to heme oxygenase & cytochrome B5

NADPH + n oxidized hemoprotein <--> NADP+ + n reduced hemoprotein

Cofactor: FAD, FMN

Structure

• in the C-terminal section; belongs to the flavoprotein pyridine nucleotide cytochrome reductase family
• contains 1 FAD-binding domain
• contains 1 flavodoxin-like domain

Compartment

• endoplasmic reticulum membrane
• peripheral membrane protein
• anchored to the ER membrane by its N-terminal hydrophobic region

Pathology

• defects in POR are the cause of adrenal hyperplasia variant type & of isolated disordered steroidogenesis (same OMIM)

More general terms

• cytochrome reductase

Database

• OMIM: https://mirror.omim.org/entry/201750
• OMIM: https://mirror.omim.org/entry/124015
• OMIM: https://mirror.omim.org/entry/207410
• UniProt: http://www.uniprot.org/uniprot/P16435.html