title: A Crk-II/TC10 signaling pathway is required for osmotic shock-stimulated glucose transport.
abstract: Osmotic shock stimulates the translocation of the glucose transporter Glut 4 to plasma membrane by a tyrosine kinase signaling pathway involving Gab-1 (the Grb2-associated binder-1 protein). We show here that, in response to osmotic shock, Gab-1 acts as a docking protein for phospholipase Cgamma1, the p85 subunit of the phosphoinositide 3-kinase and Crk-II. It has been shown that the adapter Crk-II is constitutively associated with C3G, a GDP to GTP exchange factor for several small GTP-binding proteins. We found that inhibition of the activity of phosphoinositide 3-kinase or phospholipase C did not prevent the stimulation of glucose transport by osmotic shock, whereas inactivation of Rho proteins by Clostridium difficile toxin B severely inhibited glucose uptake. Among the Rho family members, overexpression of dominant-interfering TC10/T31N mutant inhibited osmotic shock-mediated Glut 4 translocation suggesting that TC10 is required for this process. Further, disruption of cortical actin integrity by latrunculin B or jasplakinolide severely impaired osmotic shock-induced glucose transport. In contrast, osmotic shock increased the amount of cortical actin associated with caveolin-enriched plasma membrane domains. These data provide the first evidence that activation of TC10 and remodeling of cortical actin, which could occur through the TC10 signaling, are required for osmotic shock-mediated Glut 4 translocation and glucose uptake.
authors.affiliation: INSERM U 568 and IFR 50, Faculté de médecine, avenue de Valombrose, 06107 Nice, Cedex 02, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Gual
authors.forename: Satoshi
authors.initials: S
authors.lastname: Shigematsu
authors.forename: Makoto
authors.initials: M
authors.lastname: Kanzaki
authors.forename: Thierry
authors.initials: T
authors.lastname: Grémeaux
authors.forename: Teresa
authors.initials: T
authors.lastname: Gonzalez
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Pessin
authors.forename: Yannick
authors.initials: Y
authors.lastname: Le Marchand-Brustel
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Tanti
mesh_terms: D016475:3T3 Cells; D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001692:Biological Transport; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002478:Cells, Cultured; D003847:Deoxyglucose / Q000378:metabolism; D047630:Depsipeptides; D004591:Electrophoresis, Polyacrylamide Gel; D005947:Glucose / Q000378:metabolism* / Q000493:pharmacokinetics; D051275:Glucose Transporter Type 4; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D008856:Microscopy, Fluorescence; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009004:Monosaccharide Transport Proteins / Q000378:metabolism; D009124:Muscle Proteins; D009995:Osmosis; D009997:Osmotic Pressure; D010456:Peptides, Cyclic / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051966:Phospholipase C gamma; D010750:Phosphoproteins / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D021381:Protein Transport; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D050737:Proto-Oncogene Proteins c-crk; D015398:Signal Transduction; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism; D014443:Tyrosine / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003847:Deoxyglucose; D047630:Depsipeptides; D005947:Glucose; D051275:Glucose Transporter Type 4; D007527:Isoenzymes; D020928:Mitogen-Activated Protein Kinases; D009004:Monosaccharide Transport Proteins; D009124:Muscle Proteins; D010456:Peptides, Cyclic; D019869:Phosphatidylinositol 3-Kinases; D051966:Phospholipase C gamma; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D050737:Proto-Oncogene Proteins c-crk; D013844:Thiazoles; D053778:Thiazolidines; D010738:Type C Phospholipases; D014443:Tyrosine; D020741:rho GTP-Binding Proteins; C490897:Gab1 protein, mouse; C495693:Slc2a4 protein, mouse; C057531:jasplakinolide; C503260:Rhoq protein, mouse; C037068:latrunculin B