Light‐induced binding of 48‐kDa protein to photoreceptor membranes is highly enhanced by phosphorylation of rhodopsin

FEBS Letters

Wilden, U.¹  Kühn, H.¹  Hall, S.W.¹ 

[1] Institut für Neurobiologie der Kernforschungsanlage Jülich, Postfach 1913, D-5170 Jülich, FRG

关键词: Rhodopsin;    Phosphorylation;    Light-dependence;    48-kDa protein;    GTP-binding protein;    Photoreceptor;    G-protein;    GTP-binding protein;    GTPγS;    guanosine 5'-O-(3-thiotriphosphate);    AMP-PNP;    adenylyl imidodiphosphate;    R∗;    photoexcited rhodopsin;    P.-disks;    phosphorylated and regenerated disk membranes;    C.-disks;    unphosphorylated control membranes;   

DOI  :  10.1016/0014-5793(84)81221-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The 48-kDa protein, a major protein of rod photoreceptor cells, is soluble in the dark but associates with the disk membranes when some (5–10%) of their rhodopsin has absorbed light and if this rhodopsin is additionally phosphorylated by ATP and rhodopsin kinase. If rhodopsin has been phosphorylated and regenerated prior to the protein binding experiment, the binding of 48-kDa protein depends on light but no longer on the presence of ATP. Another photoreceptor protein, GTP-binding protein, associates with both phosphorylated and unphosphorylated rhodopsin upon illumination. Excess GTP-binding protein thereby displaces 48-kDa protein from phosphorylated disks; this indicates competition between these two proteins for binding sites on illuminated phosphorylated rhodopsin molecules.

【 授权许可】

Unknown