Monoclonal antibodies to chicken iodopsin

The protein moiety of chicken iodopsin, R-photopsin, was purified from the chicken retina using a sucrose flotation method followed by two steps of column chromatography. Apparent molecular weights of R-photopsin and scotopsin (the protein moiety of chicken rhodopsin), which was partly purified in the process of purification of R-photopsin, were estimated to be 34,000 and 36,000, respectively, by sodium docecylsulfate-polyacrylamide gel electrophoresis. Using the purified R-photopsin as an antigen, four kinds of hybridoma cells which secreted monoclonal antibodies specific for R-photopsin and iodopsin were prepared. The antibodies thus obtained reacted with neither other chicken cone visual pigments nor rhodopsin as analyzed by immunoblots and immunoprecipitation methods. All the monoclonal antibodies stained the majority of the cone outer segments in chicken retina, while an antiserum raised against cattle rhodopsin stained the rod outer segments as well as some cone outer segments in the retina.