TY - JOUR
T1 - A Crk-II/TC10 signaling pathway is required for osmotic shock-stimulated glucose transport
AU - Gual, Philippe
AU - Shigematsu, Satoshi
AU - Kanzaki, Makoto
AU - Grémeaux, Thierry
AU - Gonzalez, Teresa
AU - Pessin, Jeffrey E.
AU - Le Marchand-Brustel, Yannick
AU - Tanti, Jean François
PY - 2002/11/15
Y1 - 2002/11/15
N2 - 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 Cγ1, 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.
AB - 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 Cγ1, 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.
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U2 - 10.1074/jbc.M203042200
DO - 10.1074/jbc.M203042200
M3 - Article
C2 - 12215429
AN - SCOPUS:0347520946
SN - 0021-9258
VL - 277
SP - 43980
EP - 43986
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 46
ER -