[GTP-binding proteins of the retinal photoreceptor membranes: purification, antibodies].

A scheme of immunization of rabbits with partially purified GTP-binding proteins isolated from ox retinal photoreceptor membranes has been developed. Using double radial immunodiffusion, it was shown that rabbit antiserum interacts with the GTP-binding proteins of the retinal phosphoreceptor membranes of ox, pig and frog. The antibodies interaction with the GTP-binding proteins of ox retinal rod outer segments was followed by immunoelectrophoresis as well as by elimination of the activating effect of the non-hydrolyzable derivative of GTP, guanyl-5'-yl-imidodiphosphate on cyclic nucleotide phosphodiesterase in illuminated photoreceptor membranes and in their extracts. A similar effect was exerted by immunoglobulins from immunized animals on the enzyme activation by NaF. Purified immunoglobulins type G did not practically interact with the GTP-binding proteins of the photoreceptor membranes.