Retinol Dehydrogenase 13 (RDH13)

Retinol dehydrogenase 13 (RDH13) is a recently identified short-chain dehydrogenase/reductase related to microsomal retinoid oxidoreductase RDH11. RDH13 exhibits a wide tissue distribution and, by contrast with other members of the RDH11-like group of short-chain dehydrogenases/reductases, is a mitochondrial rather than a microsomal protein. Protease protection assays suggest that RDH13 is localized on the outer side of the inner mitochondrial membrane. Kinetic analysis of the purified protein shows that RDH13 is catalytically active and recognizes retinoids as substrates. The localization of RDH13 at the entrance to the mitochondrial matrix suggests that it may function to protect mitochondria against oxidative stress associated with the highly reactive retinaldehyde produced from dietary β-carotene.