Regulation of cardiac insulin receptor function by guanosine nucleotides

FEBS Letters

Russ, Martina¹  Reinauer, Hans¹  Eckel, Jürgen¹ 

[1] Laboratory of Molecular Cardiology, Diabetes Research Institute, 4000 Düsseldorf 1, Germany

关键词: Isolated cardiac myocyte;    Insulin receptor;    Guanosine nucleotide binding protein;    Tyrosine kinase;    GTP;    guanosine 5′-O-(3-thiotriphosphate);    GDP;    guanosine 5′-O-(2-thiodiphosphate);    SDS-PAGE;    sodium dodecyl sulfate-polyacrylamide gel electrophoresis;    HEPES;    4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid;    WGA;    wheat germ agglutinin;    AMP-PNP;    adenyl-5′-yl imidodiphosphate;   

DOI  :  10.1016/0014-5793(92)81464-W

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The present study examined the effect of [³⁵S]GTP on the function of insulin receptors partially purified from adult rat cardiomyocytes by WGA chromatography. [³⁵S]GTP increased receptor autophosphorylation about two times and fully mimicked the stimulatory action of insulin on poly(Glu:Tyr) phosphorylation with no additional effect of the hormone. The effect of [³⁵S]GTP was specific, dose-dependent, and due to an increase in the V _max of the kinase. In the presence of ATP or AMP-PNP, insulin significantly enhanced the binding of [³⁵S]GTP to the partially purified insulin receptor. The findings suggest coupling of the insulin receptor to a G-protein which may be involved in the regulation of tyrosine kinase activity.

【 授权许可】

Unknown