ATP-independent deactivation of squid rhodopsin.
Vis Neurosci
; 9(6): 595-602, 1992 Dec.
Article
en En
| MEDLINE
| ID: mdl-1450111
Deactivation of light-activated squid rhodopsin was studied in vitro using GTP gamma S binding by G-protein as a direct measure of rhodopsin activity. Deactivation was inhibited by dilution of the retinal suspension or by removal of soluble components. Deactivation could be restored by addition of soluble material to washed membranes. These results indicate that the deactivation is not due entirely to a conformational transition within rhodopsin itself, but depends on the interaction with other molecules. The possibility that phosphorylation is involved in the deactivation was studied. Deactivation occurred in the presence and absence of added ATP. Deactivation also occurred in the presence of kinase inhibitors and after addition of apyrase, which reduced residual ATP levels to below 1 microM. These results indicate that light-induced phosphorylation is not required for deactivation of squid rhodopsin. In this regard deactivation of squid rhodopsin is different from that of vertebrate rhodopsin, which requires phosphorylation.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Retina
/
Rodopsina
/
Adenosina Trifosfato
/
Proteínas del Ojo
Límite:
Animals
Idioma:
En
Revista:
Vis Neurosci
Año:
1992
Tipo del documento:
Article
Pais de publicación:
Reino Unido