Retinoids dehydrogenase/reductase with a clear preference for NADP. Displays high activity towards 9-cis, 11-cis and all-trans-retinal. Shows very weak activity towards 13-cis-retinol (, ). Also exhibits activity, albeit with lower affinity than for retinaldehydes, towards lipid peroxidation products (C9 aldehydes) such as 4-hydroxynonenal and trans-2-nonenal (, ). May play an important function in photoreceptor cells to detoxify 4-hydroxynonenal and potentially other toxic aldehyde products resulting from lipid peroxidation . Has no dehydrogenase activity towards steroids (, ).
Subcellular locations: Endoplasmic reticulum membrane
Widely expressed, mostly in retina, kidney, brain, skeletal muscle, pancreas and stomach.