Insulin signaling diverges into Akt-dependent and -independent signals to regulate the recruitment/docking and the fusion of GLUT4 vesicles to the plasma membrane.

ABSTRACT: Insulin modulates glucose disposal in muscle and adipose tissue by regulating the cellular redistribution of the GLUT4 glucose transporter. Protein kinase Akt/PKB is a central mediator of insulin-regulated translocation of GLUT4; however, the GLUT4 trafficking step(s) regulated by Akt is not known. Here, we use acute pharmacological Akt inhibition to show that Akt is required for insulin-stimulated exocytosis of GLUT4 to the plasma membrane. Our data also suggest that the AS160 Rab GAP is not the only Akt target required for insulin-stimulated GLUT4 translocation. Using a total internal reflection microscopy assay, we show that Akt activity is specifically required for an insulin-mediated prefusion step involving the recruitment and/or docking of GLUT4 vesicles to within 250 nm of the plas

SUBMITTER: Gonzalez E 

PROVIDER: S-EPMC1635362 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature