Insulin activates protein kinase B, inhibits glycogen synthase kinase‐3 and activates glycogen synthase by rapamycin‐insensitive pathways in skeletal muscle and adipose tissue

FEBS Letters

Cross, Darren A.E.¹  Watt, Peter W.⁴  Shaw, Morag¹  Downes, C.Peter²  van der Kaay, Jeroen²  Holder, Julie C.³  Cohen, Philip¹ 

[1] MRC Protein Phosphorylation Unit, Department of Biochemistry, University of Dundee, Dundee DD1 4HN, UK;Department of Biochemistry, University of Dundee, Dundee DD1 4HN, UK;SmithKline Beecham Pharmaceuticals, Harlow, UK;Department of Anatomy and Physiology, University of Dundee, Dundee DD1 4HN, UK

关键词: Insulin;    EGF;    Protein kinase B;    Glycogen synthase kinase 3;    Glycogen synthase;    Rapamycin;   

DOI  :  10.1016/S0014-5793(97)00240-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Insulin stimulated protein kinase Bα (PKBα) more than 10-fold and decreased glycogen synthase kinase-3 (GSK3) activity by 50±10% in skeletal muscle and adipocytes. Rapamycin did not prevent the activation of PKB, inhibition of GSK3 or stimulation of glycogen synthase up to 5 min. Thus rapamycin-insensitive pathways mediate the acute effect of insulin on glycogen synthase in the major insulin-responsive tissues. The small and very transient effects of EGF on phosphatidylinositol (3,4,5)P₃ PKBα and GSK3 in adipocytes, compared to the strong and sustained effects of insulin, explains why EGF does not stimulate glucose uptake or glycogen synthesis in adipocytes

【 授权许可】

Unknown