Light-enhanced cross-linking of rhodopsin in rod outer segment membranes as detected by chemical probes.
Bovine rod outer segment membranes were treated with cross-linking reagents before and after light exposure. Bleached membranes showed enhanced cross-linking with difluorodinitrobenzene or methyl acetimidate compared to dark-adapted membranes. The light-induced enhancement of cross-linking may be due to increased association of rhodopsin monomers in the light and/or due to increased reactivity of amino and sulfhydryl groups of bleached rhodopsin. In some instances, the band ascribed to the rhodopsin monomer in gel electrophoresis appears as a partially resolved doublet. Treatment of bleached rod outer segment membranes with methyl acetimidate improved the resolution of the doublet into two closely migrating bands.
D000818:Animals; D002417:Cattle; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004139:Dinitrofluorobenzene / Q000031:analogs & derivatives / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D007096:Imidoesters / Q000494:pharmacology; D066298:In Vitro Techniques; D008027:Light; D010786:Photoreceptor Cells / Q000528:radiation effects*; D012168:Retinal Pigments / Q000528:radiation effects*; D012243:Rhodopsin / Q000528:radiation effects*; D012374:Rod Cell Outer Segment / Q000187:drug effects / Q000528:radiation effects*
D003432:Cross-Linking Reagents; D007096:Imidoesters; D012168:Retinal Pigments; D012243:Rhodopsin; C010222:methyl acetimidate; D004139:Dinitrofluorobenzene; C002041:1,5-difluoro-2,4-dinitrobenzene