Retinal Pigment Epithelium Specific Protein 65kDa (RPE65) Antibody – Mouse Monoclonal

This gene encodes a protein which is located in the retinal pigment epithelium and is involved in the production of 11-cis retinal and in visual pigment regeneration. There are two forms of this protein, a soluble form called sRPE65, and a palmitoylated, membrane-bound form known as mRPE65. mRPE65 serves as the palmitoyl donor for lecithin retinol acyl transferase (LRAT), the enzyme that catalyzes the vitamin A to all trans retinol step of the chromophore regeneration process. Both mRPE65 and sRPE65 also serve as regulatory proteins, with the ratio and concentrations of these molecules playing a role in the inhibition of 11-cis retinal synthesis. Mutations in this gene have been associated with Leber congenital amaurosis type 2 (LCA2) and retinitis pigmentosa. [provided by RefSeq]

RPE65: Plays important roles in the production of 11-cis retinal and in visual pigment regeneration. The soluble form binds vitamin A (all-trans-retinol), making it available for LRAT processing to all-trans-retinyl ester. The membrane form, palmitoylated by LRAT, binds all-trans-retinyl esters, making them available for IMH (isomerohydrolase) processing to all-cis- retinol. The soluble form is regenerated by transferring its palmitoyl groups onto 11-cis-retinol, a reaction catalyzed by LRAT. The enzymatic activity is linearly dependent of the expression levels and membrane association. Defects in RPE65 are the cause of Leber congenital amaurosis type 2 (LCA2). LCA designates a clinically and genetically heterogeneous group of childhood retinal degenerations, generally inherited in an autosomal recessive manner. Affected infants have little or no retinal photoreceptor function as tested by electroretinography. LCA represents the most common genetic cause of congenital visual impairment in infants and children. Defects in RPE65 are the cause of retinitis pigmentosa type 20 (RP20). RP leads to degeneration of retinal photoreceptor cells. Patients typically have night vision blindness and loss of midperipheral visual field. As their condition progresses, they lose their far peripheral visual field and eventually central vision as well. Defects in RPE65 are a cause of autosomal dominant retinitis pigmentosa with choroidal involvement (PubMed:21654732). Affected individuals show reduction of central vision, constriction of visual fields, night blindness and chorioretinal atrophy. Belongs to the carotenoid oxygenase family.

Protein type: EC 3.1.1.64; Cofactor and Vitamin Metabolism - retinol

Chromosomal Location of Human Ortholog: 1p31

Cellular Component: endoplasmic reticulum; plasma membrane

Molecular Function: metal ion binding; retinal isomerase activity

Biological Process: phototransduction, visible light; retinal homeostasis; retinal metabolic process; visual perception; retinol metabolic process; insulin receptor signaling pathway; detection of light stimulus involved in visual perception; retinoid metabolic process; regulation of rhodopsin gene expression; vitamin A metabolic process; retina morphogenesis in camera-type eye

Disease: Leber Congenital Amaurosis 2; Retinitis Pigmentosa 20