Rhodopsin expressed in Chinese hamster ovary cells regulates adenylyl cyclase activity.
The cDNA encoding bovine opsin was transfected into Chinese hamster ovary (CHO) cells to generate stable clones expressing the rod cell photoreceptor protein. Cells expressing opsin, when incubated in 11-cis retinal and exposed to light, inhibited forskolin-stimulated adenylyl cyclase activity. Rhodopsin-mediated inhibition of adenylyl cyclase was prevented by treatment of cells with pertussis toxin. In the same cells, thrombin stimulated phosphatidylinositol hydrolysis through G protein-mediated pathways, but rhodopsin neither significantly influenced the action of thrombin nor stimulated phosphatidylinositol hydrolysis. Our findings indicate that rhodopsin selectively regulates a Gi protein in intact CHO cells that is coupled to adenylyl cyclase but not to phospholipase C.
Weiss
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ER
National Jewish Center for Immunology and Respiratory Medicine, Denver, Colorado 80206.
Heller-Harrison
R A
RA
Diez
E
E
Crasnier
M
M
Malbon
C C
CC
Johnson
G L
GL
D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; D000818:Animals; D002460:Cell Line; D005576:Colforsin / Q000494:pharmacology; D006224:Cricetinae; D004247:DNA / Q000235:genetics; D005260:Female; D019204:GTP-Binding Proteins / Q000502:physiology; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000378:metabolism; D008027:Light; D010053:Ovary; D037342:Pertussis Toxin; D010716:Phosphatidylinositols / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology*; D012168:Retinal Pigments / Q000494:pharmacology*; D012172:Retinaldehyde / Q000494:pharmacology; D012243:Rhodopsin / Q000235:genetics / Q000494:pharmacology*; D013873:Thionucleotides / Q000378:metabolism; D013917:Thrombin / Q000494:pharmacology; D014162:Transfection; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; D010716:Phosphatidylinositols; D011994:Recombinant Proteins; D012168:Retinal Pigments; D013873:Thionucleotides; D010566:Virulence Factors, Bordetella; D005576:Colforsin; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate; D004247:DNA; D012243:Rhodopsin; D037342:Pertussis Toxin; D013917:Thrombin; D019204:GTP-Binding Proteins; D012172:Retinaldehyde