Chicken red-sensitive cone visual pigment retains a binding domain for transducin

• Published in: FEBS letters Vol. 246; no. 1; pp. 69 - 72
• Main Authors: Fukada, Yoshitaka, Okano, Toshiyuki, Artamonov, Igor D., Yoshizawa, Tôru
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 27.03.1989
• Subjects: Animals; Binding Sites; Catalysis; Chaps, (3-[(3-cholamidopropyl)dimethylammoniol-1-propanesulfonate); Chicken retina; Chickens; Cone visual pigment; DTT, dithiothreitol; Electrophoresis, Polyacrylamide Gel; GppNHp, guanosine-5′-(β,γ-imido)triphosphate; GTP-binding protein; Guanylyl Imidodiphosphate - metabolism; Iodopsin; Light; Liposomes - metabolism; Macromolecular Substances; PC, fresh egg-yolk phosphatidylcholine; PhMeSO2F, phenylmethylsulfonyl fluoride; Phosphatidylcholines; Retina - analysis; Retinal Pigments - metabolism; Retinal Pigments - radiation effects; Rhodopsin; Rhodopsin - metabolism; Rhodopsin - radiation effects; Rod Opsins; Transducin; Transducin - metabolism; Cone visual pigment; GTP-binding protein; PC, fresh egg-yolk phosphatidylcholine; Chaps, (3-[(3-cholamidopropyl)dimethylammoniol-1-propanesulfonate); Rhodopsin; GppNHp, guanosine-5′-(β,γ-imido)triphosphate; Iodopsin; Transducin; PhMeSO 2F, phenylmethylsulfonyl fluoride; Chicken retina; DTT, dithiothreitol
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(89)80255-8

Iodopsin (a red-sensitive cone visual pigment) and rhodopsin (a rod pigment) were isolated from chicken retina. They were separately reconstituted into phosphatidylcholine liposomes and then mixed with rod transducin (Tα and Tβγ) purified from bovine retina. Iodopsin enhanced, only when irradiated, the binding of GppNHp to Tα to a similar extent to irradiated rhodopsin. Furthermore, the binding of GppNHp to Tα in the presence of a photobleaching intermediate of iodopsin preferably required Tβγ-2 rather than Tβγ-1, which is very similar in profile to that in the presence of the intermediate of rhodopsin (J. Biol. Chem., in press). These results indicate that the binding domain for transducin in iodopsin should closely resemble that in rhodopsin.