title: Light-stimulated phosphorylation of rhodopsin in the retina: the presence of a protein kinase that is specific for photobleached rhodopsin.
abstract: A protein kinase has been extracted from bovine rod outer segments by a mild procedure. The enzyme acts specifically on photobleached, not unbleached, rhodopsin and will not catalyze the phosphorylation of histones, phosvitin, or casein. We propose the name "opsin kinase" for the enzyme, which is not affected by cyclic nucleotides but which is inhibited by theophylline. Preparations of purified rod outer segments, however, appear to contain only low concentration of opsin phosphatase activity.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002364:Caseins / Q000378:metabolism; D002417:Cattle; D000242:Cyclic AMP / Q000494:pharmacology; D006152:Cyclic GMP / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D006657:Histones / Q000378:metabolism; D008027:Light; D010710:Phosphates / Q000378:metabolism; D010726:Phosphodiesterase Inhibitors; D010761:Phosphorus Radioisotopes; D010775:Photic Stimulation; D010786:Photoreceptor Cells / Q000201:enzymology* / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism*; D012168:Retinal Pigments / Q000378:metabolism*; D012243:Rhodopsin / Q000378:metabolism*; D013806:Theophylline / Q000494:pharmacology
chemical_list: D002364:Caseins; D006657:Histones; D010710:Phosphates; D010726:Phosphodiesterase Inhibitors; D010761:Phosphorus Radioisotopes; D012168:Retinal Pigments; D000255:Adenosine Triphosphate; D012243:Rhodopsin; D013806:Theophylline; D000242:Cyclic AMP; D011494:Protein Kinases; D006152:Cyclic GMP