Localization of rhodopsin antibody in the retina of the frog,

Abstract

A specific immune serum against frog rhodopsin has been developed in rabbits. The specificity of the antirhodopsin serum was established using the indirect Coon's antibody technique. Absorption of the serum with electrophoretically purified rhodopsin abolished its ability to stain sections of retina or isolated retinal receptor disk membranes.Using fluorescein-labeled sheep anti-rabbit [gamma]-globulin on sections of retina treated with antirhodopsin [gamma]-globulin, fluorescence was observed in all retinal receptor outer segments and in the myoids and ellipsoids of retinal receptor inner segments. In addition, it was localized in cytoplasmic structures of the pigmented epithelium. Dissected retinas with intact outer segments showed fluorescence in the outer segments when the retinas were treated with antirhodopsin immune serum, washed thoroughly, incubated in fluorescein-labeled sheep anti-rabbit [gamma]-globulin and again washed thoroughly. This is suggestive of a diffusion pathway into the outer segments. Isolated whole rod outer segments and isolated disk membranes stained uniformly by the indirect technique. From these observations we conclude that the photopigment is indeed part of the disk membranes of the outer segments and that the external membrane of the outer segment also contains photopigment. Use of the specific antirhodopsin immune serum has allowed the description of the molecular arrangement of photopigment in retinal receptor disk membranes (Blasie, Worthington & Dewey, 1968; Blasie & Worthington, 1969).