A NOVEL MEMBER OF THE IG SUPERFAMILY, RPE7, EXPRESSED ON THE RETINAL-PIGMENT EPITHELIAL-CELL AND MULLER CELL OF THE BOVINE RETINA

The retinal pigment epithelium of the vertebrate eye plays a major par t in the maintenance of ocular function. To identify molecules involve d in the exertion of their physiological functions, monoclonal antibod ies against bovine retinal pigment epithelial cells were made. Analysi s by immunofluorescence and immunoelectron microscopy showed that one of the monoclonal antibodies named anti-RPE7 stained the cell surface of retinal pigment epithelial cells and Muller cells. The anti-RPE7 an tibody was revealed to recognize molecules of 45-55 kDa by Western blo t analysis. Molecular cloning of the RPE7 cDNA and sequence analysis o f the amino acids revealed that protein RPE7 belonged to the Ig superf amily. The high homology of RPE7 with metalloproteinase inducer sugges ts that the protein RPE7 might play a role in the matrix (interphotore ceptor matrix and basement membranes) remodeling as well as in retinal pigment epithelial cell migration under pathological conditions. (C) 1998 Academic Press.