Dehydrogenase/reductase SDR family member 4; Reduces all-trans-retinal and 9-cis retinal. Can also catalyze the oxidation of all-trans-retinol with NADP as co-factor, but with much lower efficiency. Reduces alkyl phenyl ketones and alpha- dicarbonyl compounds with aromatic rings, such as pyrimidine-4- aldehyde, 3-benzoylpyridine, 4-benzoylpyridine, menadione and 4- hexanoylpyridine. Has no activity towards aliphatic aldehydes and ketones (By similarity); Belongs to the short-chain dehydrogenases/reductases (SDR) family.

Aldo-keto reductase family 1 member C4; Catalyzes the transformation of the potent androgen dihydrotestosterone (DHT) into the less active form, 5-alpha-androstan- 3-alpha,17-beta-diol (3-alpha-diol). Also has some 20-alpha- hydroxysteroid dehydrogenase activity. The biotransformation of the pesticide chlordecone (kepone) to its corresponding alcohol leads to increased biliary excretion of the pesticide and concomitant reduction of its neurotoxicity since bile is the major excretory route; Belongs to the aldo/keto reductase family.

Aldehyde dehydrogenase family 1 member A3; NAD-dependent aldehyde dehydrogenase that catalyzes the formation of retinoic acid. Has high activity with all-trans retinal, and has much lower in vitro activity with acetaldehyde. Required for the biosynthesis of normal levels of retinoic acid in the embryonic ocular and nasal regions; retinoic acid is required for normal embryonic development of the eye and the nasal region (By similarity).

Lecithin retinol acyltransferase; Transfers the acyl group from the sn-1 position of phosphatidylcholine to all-trans retinol, producing all-trans retinyl esters. Retinyl esters are storage forms of vitamin A (Probable). LRAT plays a critical role in vision (Probable). It provides the all-trans retinyl ester substrates for the isomerohydrolase which processes the esters into 11-cis-retinol in the retinal pigment epithelium; due to a membrane-associated alcohol dehydrogenase, 11 cis-retinol is oxidized and converted into 11-cis- retinaldehyde which is the chromophore for rhodopsin and t [...]

Cytochrome P450 26A1; A cytochrome P450 monooxygenase involved in the metabolism of all-trans retinoic acid (atRA), a signaling molecule that binds to retinoic acid receptors and regulates gene transcription. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (CPR; NADPH- ferrihemoprotein reductase). Catalyzes the hydroxylation of carbon hydrogen bonds of atRA primarily at C-4 and C-18. Has no activity toward 9-cis and 13-cis retinoic acid st [...]

Retinal dehydrogenase 1; Can convert/oxidize retinaldehyde to retinoic acid. Binds free retinal and cellular retinol-binding protein-bound retinal (By similarity). May have a broader specificity and oxidize other aldehydes in vivo.

Aldo-keto reductase family 1 member C2; Works in concert with the 5-alpha/5-beta-steroid reductases to convert steroid hormones into the 3-alpha/5-alpha and 3-alpha/5- beta-tetrahydrosteroids. Catalyzes the inactivation of the most potent androgen 5-alpha-dihydrotestosterone (5-alpha-DHT) to 5-alpha- androstane-3-alpha,17-beta-diol (3-alpha-diol). Has a high bile-binding ability.

Retinal dehydrogenase 2; Converts retinaldehyde to retinoic acid. Recognizes as substrates free retinal and cellular retinol-binding protein-bound retinal. Can metabolize octanal and decanal, but has only very low activity with benzaldehyde, acetaldehyde and propanal. Displays complete lack of activity with citral (By similarity). Belongs to the aldehyde dehydrogenase family.

Aldo-keto reductase family 1 member C3; Catalyzes the conversion of aldehydes and ketones to alcohols. Catalyzes the reduction of prostaglandin (PG) D2, PGH2 and phenanthrenequinone (PQ) and the oxidation of 9-alpha,11-beta-PGF2 to PGD2. Functions as a bi-directional 3-alpha-, 17-beta- and 20-alpha HSD. Can interconvert active androgens, estrogens and progestins with their cognate inactive metabolites. Preferentially transforms androstenedione (4-dione) to testosterone; Belongs to the aldo/keto reductase family.