Monoclonal antibody labels both rod and cone outer segments of turtle photoreceptors.
We have studied the immunoreactivity of turtle photoreceptors to a monoclonal antibody (MAb 15-18) which binds to the external loop connecting bovine rhodopsin helices IV-V. Three chromatic types of cone photoreceptors were identified by the presence and color of oil droplets. MAb 15-18 intensely labeled the outer segments of both rods and green cones. In addition, a weak cross-reactivity was also found in the outer segments of red cones having a pale-green oil droplet, and of blue cones. Other morphological subtypes of red cones, cones with a red oil droplet and both members of double cones, showed no labeling. Our results indicate that rhodopsin and green cone opsin have a similar antigenic determinant, and that two different structural forms of red cone opsin may be present in the turtle retina.
Department of Information Physiology, National Institute for Physiological Sciences, Okazaki, Japan.
T
T
Ohtsuka
K
K
Kawamata
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D003429:Cross Reactions; D000939:Epitopes / Q000032:analysis; D005136:Eye Proteins / Q000032:analysis / Q000276:immunology; D007124:Immunoenzyme Techniques; D010786:Photoreceptor Cells / Q000032:analysis*; D012168:Retinal Pigments / Q000032:analysis / Q000276:immunology*; D012243:Rhodopsin / Q000032:analysis / Q000276:immunology; D012374:Rod Cell Outer Segment / Q000032:analysis*; D017299:Rod Opsins; D014426:Turtles / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D000939:Epitopes; D005136:Eye Proteins; D012168:Retinal Pigments; D017299:Rod Opsins; D012243:Rhodopsin