Zonulas Occluden 1 Expression in retinas from Rho–/– C129 mice

Abstract

Abstract: : Purpose:Retinitis pigmentosa (RP) comprises a heterogenous group of inherited diseases that are characterised by primary degeneration of rod photoreceptors and secondary degeneration of cone photoreceptors in the retina, and additional pathologic changes include vascular changes and invasion of the inner retina by retinal pigment epithelial (RPE) cells. RP represents a major cause of progressive retinal disease worldwide. Methods:Levels of the tight junction protein ZO–1 were determined in retinal extracts from Rho–/– mice by western blotting analysis, and by confocal microscopy. ZO–1 gene expression was determined by gene microarray and real–time PCR. Results:Increased expression of the tight junction protein ZO–1 was found in Rho–/– mice at 6 weeks of age, compared to wild type C129 mice, by Confocal Scanning Laser microscopy, Western Blotting and gene microarray analyses and may represent a specific early pathogenic response at the outer blood retinal barrier. The pattern of staining observed by fluorescence microscopy showed positive staining for retinal pigment epithelial cells. Some diffuse staining was detected in the outer limiting membrane. Conclusions:ZO–1 may be important in maintaining retinal architecture and in stabilising the arrangement of the photoreceptor cells. The retinal changes following photoreceptor death contribute to pathogenesis and affect therapies aimed at promoting survival of mutant photoreceptors.

Keywords: retinitis • retinal pigment epithelium • cell adhesions/cell junctions