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MGP003834

UniProt Annotations

Entry Information

Gene Name	lecithin retinol acyltransferase (phosphatidylcholine--retinol O-acyltransferase)
Protein Entry	LRAT_HUMAN
UniProt ID	O95237
Species	Human

Comments

Comment type	Description
Catalytic Activity	Phosphatidylcholine + retinol--[cellular- retinol-binding-protein] = 2-acylglycerophosphocholine + retinyl- ester--[cellular-retinol-binding-protein].
Disease	Leber congenital amaurosis 14 (LCA14) [MIM:613341]: A severe dystrophy of the retina, typically becoming evident in the first years of life. Visual function is usually poor and often accompanied by nystagmus, sluggish or near-absent pupillary responses, photophobia, high hyperopia and keratoconus. {ECO:0000269\|PubMed:11381255, ECO:0000269\|PubMed:17011878, ECO:0000269\|PubMed:18055821}. Note=The disease is caused by mutations affecting the gene represented in this entry.
Enzyme Regulation	Inhibited by all-trans-retinyl alpha- bromoacetate and N-boc-L-biocytinyl-11-aminoundecane chloro-methyl ketone (BACMK). {ECO:0000269\|PubMed:9920938}.
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. {ECO:0000269\|PubMed:9920938}.
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 (By similarity). {ECO:0000250}.
Pathway	Cofactor metabolism; retinol metabolism.
Similarity	Belongs to the H-rev107 family. {ECO:0000305}.
Subcellular Location	Endoplasmic reticulum membrane {ECO:0000250}; Single-pass membrane protein {ECO:0000250}. Rough endoplasmic reticulum {ECO:0000250}. Endosome, multivesicular body {ECO:0000250}. Cytoplasm, perinuclear region {ECO:0000250}. Note=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). {ECO:0000250}.
Tissue Specificity	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. {ECO:0000269\|PubMed:18544127, ECO:0000269\|PubMed:9920938}.