Visual pigment-like receptor peropsin (RRH)

Visual pigment-like receptor peropsin (RRH) is an opsin-family G protein-coupled receptor predominantly expressed in the apical microvilli of the retinal pigment epithelium (RPE) in the eye[1][5][6][7]. Current evidence suggests RRH/peropsin may regulate RPE physiology either by directly detecting light or by monitoring concentrations of retinoids (such as vitamin A derivatives) or other photoreceptor-derived compounds[1][4][5][6]. RRH is thought to play a role in retinal vitamin A metabolism, mediating either storage or movement of vitamin A between the retina and the RPE[1][5]. Mechanistically, peropsin forms a pigment by binding retinal (vitamin A aldehyde), and, in some organisms, is thought to act as a retinal photoisomerase, catalyzing the conversion of all-trans-retinal to 11-cis-retinal in the dark, although its isomerase activity is far lower than some other opsins[1][2]. RRH does not have an established direct link to human disease such as retinitis pigmentosa[1][5]. No drugs or safety concerns are currently described, and the molecule is not established as a therapeutic biomarker or drug target as of now[5].

Other names

Retinal pigment epithelium-derived rhodopsin homologperopsinvisual pigment-like receptor peropsinRRHOPSX