Retinol-binding protein 3 (RBP3)

Retinol-binding protein 3 (RBP3), also known as interphotoreceptor retinoid-binding protein (IRBP), is a large glycoprotein found in the interphotoreceptor matrix of the eye, specifically between retinal pigment epithelium and photoreceptor cells. Structurally, RBP3 consists of four tandem retinoid-binding modules and can bind multiple retinoids and fatty acids, including all-trans-retinol and 11-cis-retinal, as well as docosahexaenoic acid. RBP3 acts as a transporter, shuttling retinoids between photoreceptors and retinal pigment epithelium, which is crucial for regenerating visual pigments during the visual cycle. Its conformational flexibility allows dynamic adaptation to different ligands, which is vital for efficient transport. Disruption or loss of RBP3 expression is linked to several retinal diseases, such as diabetic retinopathy, retinitis pigmentosa, and myopia. It is not a drug target in the classic therapeutic sense (such as a receptor or enzyme), and there are currently no drugs directly targeting it, but its levels may serve as a biomarker for ocular health and disease progression[1][2][3][4].

Other names

Interphotoreceptor retinoid-binding proteinIRBPD10S64D10S65D10S66RP66Interstitial retinol-binding protein