Role for the microtubule cytoskeleton in GLUT4 vesicle trafficking and in the regulation of insulin-stimulated glucose uptake.

ABSTRACT: Insulin stimulates glucose uptake into adipocytes by promoting the translocation of the glucose transporter isoform 4 (GLUT4) from intracellular vesicles to the plasma membrane. In 3T3-L1 adipocytes GLUT4 resides both in an endosomal pool, together with transferrin receptors, and in a unique pool termed 'GLUT4 storage vesicles' (GSVs), which excludes endosomal proteins. The trafficking of GLUT4 vesicles was studied in living 3T3-L1 adipocytes by time-lapse confocal microscopy of GLUT4 tagged with green fluorescent protein. GLUT4 vesicles exhibited two types of motion: rapid vibrations around a point and short (generally less than 10 microm) linear movements. The linear movements were completely blocked by incubation of the cells in the presence of microtubule-depolymerizing agents. This su

SUBMITTER: Fletcher LM 

PROVIDER: S-EPMC1221456 | biostudies-literature | 2000 Dec

REPOSITORIES: biostudies-literature