TY - JOUR
T1 - Aldolase mediates the association of F-actin with the insulin-responsive glucose transporter GLUT4
AU - Kao, Aimee W.
AU - Noda, Yoichi
AU - Johnson, John H.
AU - Pessin, Jeffrey E.
AU - Saltiel, Alan R.
PY - 1999/6/18
Y1 - 1999/6/18
N2 - To identify potential proteins interacting with the insulin-responsive glucose transporter (GLUT4), we generated fusion proteins of glutathione S- transferase (GST) and the final 30 amino acids from GLUT4 (GST-G4) or GLUT1 (GST-G1). Incubation of these carboxylterminal fusion proteins with adipocyte cell extracts revealed a specific interaction of GLUT4 with fructose 1,6- bisphosphate aldolase. In the presence of aldolase, GST-G4 but not GST-G1 was able to co-pellet with filamentous (F)-actin. This interaction was prevented by incubation with the aldolase substrates, fructose 1,6-bisphosphate or glyceraldehyde 3-phosphate. Immunofluorescence confocal microscopy demonstrated a significant co-localization of aldolase and GLUT4 in intact 3T3L1 adipocytes, which decreased following insulin stimulation. Introduction into permeabilized 3T3L1 adipocytes of fructose 1,6-bisphosphate or the metabolic inhibitor 2-deoxyglucose, two agents that disrupt the interaction between aldolase and actin, inhibited insulin-stimulated GLUT4 exocytosis without affecting GLUT4 endocytosis. Furthermore, microinjection of an aldolase-specific antibody also inhibited insulin-stimulated GLUT4 translocation. These data suggest that aldolase functions as a scaffolding protein for GLUT4 and that glucose metabolism may provide a negative feedback signal for the regulation of glucose transport by insulin.
AB - To identify potential proteins interacting with the insulin-responsive glucose transporter (GLUT4), we generated fusion proteins of glutathione S- transferase (GST) and the final 30 amino acids from GLUT4 (GST-G4) or GLUT1 (GST-G1). Incubation of these carboxylterminal fusion proteins with adipocyte cell extracts revealed a specific interaction of GLUT4 with fructose 1,6- bisphosphate aldolase. In the presence of aldolase, GST-G4 but not GST-G1 was able to co-pellet with filamentous (F)-actin. This interaction was prevented by incubation with the aldolase substrates, fructose 1,6-bisphosphate or glyceraldehyde 3-phosphate. Immunofluorescence confocal microscopy demonstrated a significant co-localization of aldolase and GLUT4 in intact 3T3L1 adipocytes, which decreased following insulin stimulation. Introduction into permeabilized 3T3L1 adipocytes of fructose 1,6-bisphosphate or the metabolic inhibitor 2-deoxyglucose, two agents that disrupt the interaction between aldolase and actin, inhibited insulin-stimulated GLUT4 exocytosis without affecting GLUT4 endocytosis. Furthermore, microinjection of an aldolase-specific antibody also inhibited insulin-stimulated GLUT4 translocation. These data suggest that aldolase functions as a scaffolding protein for GLUT4 and that glucose metabolism may provide a negative feedback signal for the regulation of glucose transport by insulin.
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U2 - 10.1074/jbc.274.25.17742
DO - 10.1074/jbc.274.25.17742
M3 - Article
C2 - 10364216
AN - SCOPUS:0033580846
SN - 0021-9258
VL - 274
SP - 17742
EP - 17747
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 25
ER -