Peropsin, a Novel Visual Pigment-Like Protein Located in the Apical Microvilli of the Retinal Pigment Epithelium

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 94; no. 18; pp. 9893 - 9898
• Main Authors: Sun, Hui, Gilbert, Debra J., Copeland, Neal G., Jenkins, Nancy A., Nathans, Jeremy
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 02.09.1997; National Acad Sciences; National Academy of Sciences; The National Academy of Sciences of the USA
• Subjects: Amino Acid Sequence; Amino acids; Antibodies; Biological Sciences; Cloning, Molecular; Deoxyribonucleic acid; DNA; DNA, Complementary - genetics; DNA, Complementary - isolation & purification; Eye Proteins - genetics; Eye Proteins - metabolism; Eyes & eyesight; Genetic loci; Humans; Microscopy, Immunoelectron; Microvilli; Microvilli - metabolism; Molecular Sequence Data; Photoreceptors; Pigment Epithelium of Eye - metabolism; Pigment Epithelium of Eye - ultrastructure; Proteins; Receptors; Retina; Retinal pigments; Retinal Pigments - genetics; Retinal Pigments - metabolism; Rhodopsin; Sequence Alignment; Ungulates; Vertebrates
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.94.18.9893

A visual pigment-like protein, referred to as peropsin, has been identified by large-scale sequencing of cDNAs derived from human ocular tissues. The corresponding mRNA was found only in the eye, where it is localized to the retinal pigment epithelium (RPE). Peropsin immunoreactivity, visualized by light and electron microscopy, localizes the protein to the apical face of the RPE, and most prominently to the microvilli that surround the photoreceptor outer segments. These observations suggest that peropsin may play a role in RPE physiology either by detecting light directly or by monitoring the concentration of retinoids or other photoreceptor-derived compounds.