|
|
|
|
Vol. 17, Issue 10, 4484-4493, October 2006
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Department of Biochemistry, Weill Medical College of Cornell University, New York, NY 10021
Submitted July 10, 2006;
Revised August 3, 2006;
Accepted August 4, 2006
Monitoring Editor: Jean Gruenberg
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 plasma membrane. Moreover, the insulin-stimulated fusion of GLUT4 vesicles with the plasma membrane can occur independently of Akt activity, although based on inhibition by wortmannin, it is dependent on phosphatidylinositol 3' kinase activity. Hence, to achieve full redistribution of GLUT4 into the plasma membrane, insulin signaling bifurcates to independently regulate both fusion and a prefusion step(s).
This article was published online ahead of print in MBC in Press (http://www.molbiolcell.org/cgi/doi/10.1091/mbc.E06-07-0585) on August 16, 2006.
Address correspondence to: Timothy E. McGraw (temcgraw{at}med.cornell.edu)
This article has been cited by other articles:
![]() |
K. Funai and G. D. Cartee Contraction-stimulated glucose transport in rat skeletal muscle is sustained despite reversal of increased PAS-phosphorylation of AS160 and TBC1D1 J Appl Physiol, December 1, 2008; 105(6): 1788 - 1795. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. J. Green, O. Goransson, G. S. Kular, N. R. Leslie, A. Gray, D. R. Alessi, K. Sakamoto, and H. S. Hundal Use of Akt Inhibitor and a Drug-resistant Mutant Validates a Critical Role for Protein Kinase B/Akt in the Insulin-dependent Regulation of Glucose and System A Amino Acid Uptake J. Biol. Chem., October 10, 2008; 283(41): 27653 - 27667. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Talior-Volodarsky, V. K. Randhawa, H. Zaid, and A. Klip {alpha}-Actinin-4 Is Selectively Required for Insulin-induced GLUT4 Translocation J. Biol. Chem., September 12, 2008; 283(37): 25115 - 25123. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Blot and T. E. McGraw Molecular Mechanisms Controlling GLUT4 Intracellular Retention Mol. Biol. Cell, August 1, 2008; 19(8): 3477 - 3487. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Borthakur, R. K. Gill, S. Tyagi, A. Koutsouris, W. A. Alrefai, G. A. Hecht, K. Ramaswamy, and P. K. Dudeja The Probiotic Lactobacillus acidophilus Stimulates Chloride/Hydroxyl Exchange Activity in Human Intestinal Epithelial Cells J. Nutr., July 1, 2008; 138(7): 1355 - 1359. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Sakamoto and G. D. Holman Emerging role for AS160/TBC1D4 and TBC1D1 in the regulation of GLUT4 traffic Am J Physiol Endocrinol Metab, July 1, 2008; 295(1): E29 - E37. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. M. Song, R. C. Hresko, and M. Mueckler Identification of Amino Acid Residues within the C Terminus of the Glut4 Glucose Transporter That Are Essential for Insulin-stimulated Redistribution to the Plasma Membrane J. Biol. Chem., May 2, 2008; 283(18): 12571 - 12585. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. O. Chavez, J. C. Lopez-Alvarenga, M. E. Tejero, C. Triplitt, R. A. Bastarrachea, A. Sriwijitkamol, P. Tantiwong, V. S. Voruganti, N. Musi, A. G. Comuzzie, et al. Physiological and Molecular Determinants of Insulin Action in the Baboon Diabetes, April 1, 2008; 57(4): 899 - 908. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Jiang, J. Fan, L. Bai, Y. Wang, Y. Chen, L. Yang, L. Chen, and T. Xu Direct Quantification of Fusion Rate Reveals a Distal Role for AS160 in Insulin-stimulated Fusion of GLUT4 Storage Vesicles J. Biol. Chem., March 28, 2008; 283(13): 8508 - 8516. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Larance, G. Ramm, and D. E. James The GLUT4 Code Mol. Endocrinol., February 1, 2008; 22(2): 226 - 233. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. F. Kramer, E. B. Taylor, C. A. Witczak, N. Fujii, M. F. Hirshman, and L. J. Goodyear Calmodulin-Binding Domain of AS160 Regulates Contraction- but Not Insulin-Stimulated Glucose Uptake in Skeletal Muscle Diabetes, December 1, 2007; 56(12): 2854 - 2862. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Saito, C. C. Jones, S. Huang, M. P. Czech, and P. F. Pilch The Interaction of Akt with APPL1 Is Required for Insulin-stimulated Glut4 Translocation J. Biol. Chem., November 2, 2007; 282(44): 32280 - 32287. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Falasca, W. E. Hughes, V. Dominguez, G. Sala, F. Fostira, M. Q. Fang, R. Cazzolli, P. R. Shepherd, D. E. James, and T. Maffucci The Role of Phosphoinositide 3-Kinase C2{alpha} in Insulin Signaling J. Biol. Chem., September 21, 2007; 282(38): 28226 - 28236. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Frosig, A. J. Rose, J. T. Treebak, B. Kiens, E. A. Richter, and J. F.P. Wojtaszewski Effects of Endurance Exercise Training on Insulin Signaling in Human Skeletal Muscle: Interactions at the Level of Phosphatidylinositol 3-Kinase, Akt, and AS160 Diabetes, August 1, 2007; 56(8): 2093 - 2102. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Yoshizaki, T. Imamura, J. L. Babendure, J.-C. Lu, N. Sonoda, and J. M. Olefsky Myosin 5a Is an Insulin-Stimulated Akt2 (Protein Kinase B{beta}) Substrate Modulating GLUT4 Vesicle Translocation Mol. Cell. Biol., July 15, 2007; 27(14): 5172 - 5183. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. D'Andrea-Merrins, L. Chang, A. D. Lam, S. A. Ernst, and E. L. Stuenkel Munc18c Interaction with Syntaxin 4 Monomers and SNARE Complex Intermediates in GLUT4 Vesicle Trafficking J. Biol. Chem., June 1, 2007; 282(22): 16553 - 16566. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Huang, L. M. Lifshitz, C. Jones, K. D. Bellve, C. Standley, S. Fonseca, S. Corvera, K. E. Fogarty, and M. P. Czech Insulin Stimulates Membrane Fusion and GLUT4 Accumulation in Clathrin Coats on Adipocyte Plasma Membranes Mol. Cell. Biol., May 1, 2007; 27(9): 3456 - 3469. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. B. Arias, J. Kim, K. Funai, and G. D. Cartee Prior exercise increases phosphorylation of Akt substrate of 160 kDa (AS160) in rat skeletal muscle Am J Physiol Endocrinol Metab, April 1, 2007; 292(4): E1191 - E1200. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. L. Wieman, J. A. Wofford, and J. C. Rathmell Cytokine Stimulation Promotes Glucose Uptake via Phosphatidylinositol-3 Kinase/Akt Regulation of Glut1 Activity and Trafficking Mol. Biol. Cell, April 1, 2007; 18(4): 1437 - 1446. [Abstract] [Full Text] [PDF] |
||||