Recoverin mediates the calcium effect upon rhodopsin phosphorylation and cGMP hydrolysis in bovine retina rod cells.
Rhodopsin phosphorylation and in consequence cGMP hydrolysis in bovine rod outer segments are Ca2+ dependent in the presence of ATP. The level of rhodopsin phosphorylation decreases and the lifetime of active phosphodiesterase increases when the free [Ca2+] is raised from < 1 nM to about 1 microM; in both cases the half-maximal effect was observed at 140-170 nM of free Ca2+. Antibodies to recoverin reverse both effects at high [Ca2+] but have no influence at low [Ca2+]. We conclude that the Ca2+ effects observed are mediated by recoverin which inhibits rhodopsin kinase at a high Ca2+ level.
Gorodovikova
E N
EN
Department of Enzymology, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russian Federation.
Gimelbrant
A A
AA
Senin
I I
II
Philippov
P P
PP
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000276:immunology / Q000378:metabolism*; D002417:Cattle; D006152:Cyclic GMP / Q000378:metabolism*; D005136:Eye Proteins; D051606:G-Protein-Coupled Receptor Kinase 1; D051597:Hippocalcin; D008074:Lipoproteins; D009419:Nerve Tissue Proteins; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases / Q000378:metabolism; D051603:Recoverin; D017948:Retinal Rod Photoreceptor Cells / Q000378:metabolism*; D012243:Rhodopsin / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D002135:Calcium-Binding Proteins; D005136:Eye Proteins; D008074:Lipoproteins; D009419:Nerve Tissue Proteins; D047428:Protein Kinase Inhibitors; D051603:Recoverin; D051597:Hippocalcin; D000255:Adenosine Triphosphate; D012243:Rhodopsin; D011494:Protein Kinases; D051606:G-Protein-Coupled Receptor Kinase 1; D006152:Cyclic GMP; D002118:Calcium