catalytic activity:Phosphatidylcholine + retinol--[cellular-retinol-binding-protein] = 2-acylglycerophosphocholine + retinyl-ester--[cellular-retinol-binding-protein].,disease:Defects in LRAT are a cause of severe early-onset retinal dystrophy (RD) [MIM:604863].,enzyme regulation:Inhibited by all-trans-retinyl alpha-bromoacetate and N-boc-L-biocytinyl-11-aminoundecane chloro-methyl ketone (BACMK).,function: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. LRAT plays a critical role in vision. 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 the cone photopigments.,induction:LRAT activity is up-regulated by dietary vitamin A. Under conditions of vitamin A depletion, LRAT expression in the liver is induced by retinoic acid.,pathway:Cofactor metabolism; retinol metabolism.,similarity:Belongs to the H-rev107 family.,tissue specificity:Found at high levels in testis and liver, followed by retinal pigment epithelium, small intestine, prostate, pancreas and colon. Low expression observed in brain. In fetal tissues, expressed in retinal pigment epithelium and liver, and barely in the brain.,
Endoplasmic reticulum membrane ; Single-pass membrane protein . Rough endoplasmic reticulum . Endosome, multivesicular body . Cytoplasm, perinuclear region . Present in the rough endoplasmic reticulum and multivesicular body in hepatic stellate cells. Present in the rough endoplasmic reticulum and perinuclear region in endothelial cells (By similarity). .
Hepatic stellate cells and endothelial cells (at protein level). Found at high levels in testis and liver, followed by retinal pigment epithelium, small intestine, prostate, pancreas and colon. Low expression observed in brain. In fetal tissues, expressed in retinal pigment epithelium and liver, and barely in the brain.
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