Light-induced conformational changes in the extradiscal regions of bovine rhodopsin.
Light-induced conformational changes occurring at the cytosolic surface of rhodopsin were investigated by performing limited digestions of native and illuminated visual pigment with thermolysin, Arg-C endoproteinase, papain and proteinase K. A higher susceptibility of the extradiscal regions of the bleached pigment to the proteases were observed together with altered capacities of the digested bleached rhodopsins to activate the cGMP phosphodiesterase. The overall results strongly suggest that light induces conformational changes not only in the C-terminal end but also in the second and the third extradiscal loop of rhodopsin.
Pellicone
C
C
Nullans
G
G
Cook
N J
NJ
Virmaux
N
N
D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000378:metabolism; D000818:Animals; D002417:Cattle; D019286:Endopeptidase K; D010450:Endopeptidases / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D005136:Eye Proteins / Q000378:metabolism / Q000494:pharmacology / Q000528:radiation effects; D008027:Light; D010206:Papain / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D011487:Protein Conformation / Q000528:radiation effects; D012168:Retinal Pigments / Q000378:metabolism / Q000494:pharmacology / Q000528:radiation effects; D012243:Rhodopsin / Q000378:metabolism / Q000494:pharmacology / Q000528:radiation effects*; D012374:Rod Cell Outer Segment / Q000528:radiation effects; D017299:Rod Opsins; D012697:Serine Endopeptidases; D013820:Thermolysin / Q000378:metabolism
D005136:Eye Proteins; D010446:Peptide Fragments; D012168:Retinal Pigments; D017299:Rod Opsins; D012243:Rhodopsin; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D010450:Endopeptidases; C044499:submandibular proteinase A; D012697:Serine Endopeptidases; D019286:Endopeptidase K; D010206:Papain; D013820:Thermolysin