FunctionAsymmetrically cleaves beta-carotene at the 9',10' double bond resulting in the formation of beta-apo-10'-carotenal and beta-ionone. Besides beta-carotene, lycopene is also oxidatively cleaved. The apocarotenals formed by this enzyme may be the precursors for the biosynthesis of retinoic acid or exert unknown physiological effects.
Tissue specificityHighly expressed in retinal pigment epithelium. Also expressed in stomach, small intestine, liver, testis, kidney, adrenal gland, pancreas, heart, skeletal muscle and prostate (at protein level).
Sequence similaritiesBelongs to the carotenoid oxygenase family.