Receptor‐regulated formation of GTP[γS] with subsequent persistent Gs‐protein activation in membranes of human platelets

FEBS Letters

Jakobs, Karl H.¹  Wieland, Thomas¹ 

[1] Pharmakologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 366, D-6900 Heidelberg, FRG

关键词: Nucleoside diphosphokinase;    Gs-protein;    Adenylate cyclase;    GTP analog;    Prostaglandin E1;    Platelet membrane;    ATP[γS];    adenosine 5′-O-(3-thiotriphosphate);    GTP[γS];    guanosine 5′-O-(3-thiotriphosphate);    PGE1;    prostaglandin E1;    G-protein;    guanine nucleotide-binding regulatory protein;   

DOI  :  10.1016/0014-5793(89)80219-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Preincubation of human platelet membranes with the ATP analog ATP[γS] led to persistent adenylate cyclase activation. This stimulation was increased by copreincubation with PGE₁ and obliterated by removing endogenous GDP by the NTP-regenerating system, creatine phosphate plus creatine kinase. PGE₁ partially reversed the action of the regenerating system. Control formation of GTP[γS] from ATP[γS] and GDP in platelet membranes was apparently not stimulated by PGE₁. In contrast, in the presence of creatine phosphate plus creatine kinase, which prevented formation of GTP[γS], PGE₁ stimulated formation of this GTP analog, by partially reversing the action of the NTP-regenerating system. The data indicate that GTP[γS] can be formed by a membrane-associated nucleoside diphosphokinase from ATP[γS] and GDP, resulting in persistent G_s-protein activation, and that this process can be stimulated by an agonist-activated receptor.

【 授权许可】

Unknown