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 (By similarity). 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.

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 (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 (By similarity). Retinyl esters are storage forms of vitamin A (By similarity). LRAT plays a critical role in vision (By similarity). 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 chrom [...]

Beta,beta-carotene 15,15'-dioxygenase; Symmetrically cleaves beta-carotene into two molecules of retinal using a dioxygenase mechanism; Belongs to the carotenoid oxygenase family.

Diacylglycerol O-acyltransferase 1; Catalyzes the terminal and only committed step in triacylglycerol synthesis by using diacylglycerol and fatty acyl CoA as substrates. In contrast to DGAT2 it is not essential for survival. May be involved in VLDL (very low density lipoprotein) assembly. In liver, plays a role in esterifying exogenous fatty acids to glycerol. Functions as the major acyl-CoA retinol acyltransferase (ARAT) in the skin, where it acts to maintain retinoid homeostasis and prevent retinoid toxicity leading to skin and hair disorders.

All-trans-retinol 13,14-reductase; Catalyzes the saturation of all-trans-retinol to all-trans- 13,14-dihydroretinol. Does not exhibit any activity toward all-trans- retinoic acid, nor 9-cis, 11-cis or 13-cis-retinol isomers. May play a role in the metabolism of vitamin A. Independently of retinol conversion, may regulate liver metabolism upstream of MLXIPL/ChREBP. Required for adipocyte differentiation in a 3T3-L1 cell culture model. This effect seems not to mimic the in vivo situation in which animals show increased adiposity in the absence of RETSAT. Belongs to the carotenoid/retinoi [...]

17-beta-hydroxysteroid dehydrogenase type 6; NAD-dependent oxidoreductase with broad substrate specificity that shows both oxidative and reductive activity (in vitro). Has 17- beta-hydroxysteroid dehydrogenase activity towards various steroids (in vitro). Converts 5-alpha-androstan-3-alpha,17-beta-diol to androsterone and estradiol to estrone (in vitro). Has 3-alpha-hydroxysteroid dehydrogenase activity towards androsterone (in vitro). Has retinol dehydrogenase activity towards all-trans-retinol (in vitro).

Aldehyde dehydrogenase, cytosolic 1; Can oxidize benzaldehyde, propionaldehyde and acetaldehyde (By similarity). No detectable activity with retinal.