HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 277, Issue 50, 47972-47975, December 13, 2002

This Article Full Text Full Text (PDF) All Versions of this Article: 277/50/47972    most recent C200486200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Xu, Z. Articles by Kandror, K. V. Search for Related Content PubMed PubMed Citation Articles by Xu, Z. Articles by Kandror, K. V.

ACCELERATED PUBLICATION
Translocation of Small Preformed Vesicles Is Responsible for the Insulin Activation of Glucose Transport in Adipose Cells
EVIDENCE FROM THE IN VITRO RECONSTITUTION ASSAY^*

Zhao Xu and Konstantin V. Kandror

From the Boston University School of Medicine, Boston, Massachusetts 02118

Insulin stimulates translocation of the glucose transporter isoform 4 (Glut4) from an intracellular storage compartment to the plasma membrane in fat and skeletal muscle cells. At present, the nature of the Glut4 storage compartment is unclear. According to one model, this compartment represents a population of preformed small vesicles that fuse with the plasma membrane in response to insulin stimulation. Alternatively, Glut4 may be retained in large donor membranes, and insulin stimulates the formation of transport vesicles that deliver Glut4 to the cell surface. Finally, insulin can induce plasma membrane fusion of the preformed vesicles and, also, stimulate the formation of new vesicles. In extracts of fat and skeletal muscle cells, Glut4 is predominantly found in small insulin-sensitive 60-70 S membrane vesicles that may or may not artificially derive from large donor membranes during cell homogenization. Here, we use a cell-free reconstitution assay to demonstrate that small Glut4-containing vesicles are formed from large rapidly sedimenting donor membranes in a cytosol-, ATP-, time-, and temperature-dependent fashion and, therefore, do not represent an artifact of homogenization. Thus, small insulin-responsive vesicles represent the major form of Glut4 storage in the living adipose cell. Fusion of these vesicles with the plasma membrane may be largely responsible for the primary effect of insulin on glucose transport in fat tissue. In addition, our results suggest that insulin may also stimulate the formation of Glut4 vesicles and accelerate Glut4 recycling to the plasma membrane.

This article has been cited by other articles:

				Z. Xu, S. Yu, C.-H. Hsu, J. Eguchi, and E. D. Rosen The orphan nuclear receptor chicken ovalbumin upstream promoter-transcription factor II is a critical regulator of adipogenesis PNAS, February 19, 2008; 105(7): 2421 - 2426. [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]

				J. Shi and K. V. Kandror The Luminal Vps10p Domain of Sortilin Plays the Predominant Role in Targeting to Insulin-responsive Glut4-containing Vesicles J. Biol. Chem., March 23, 2007; 282(12): 9008 - 9016. [Abstract] [Full Text] [PDF]

				C. Yu, J. Cresswell, M. G. Loffler, and J. S. Bogan The Glucose Transporter 4-regulating Protein TUG Is Essential for Highly Insulin-responsive Glucose Uptake in 3T3-L1 Adipocytes J. Biol. Chem., March 9, 2007; 282(10): 7710 - 7722. [Abstract] [Full Text] [PDF]

				C. A. Eyster, Q. S. Duggins, G. J. Gorbsky, and A. L. Olson Microtubule Network Is Required for Insulin Signaling through Activation of Akt/Protein Kinase B: EVIDENCE THAT INSULIN STIMULATES VESICLE DOCKING/FUSION BUT NOT INTRACELLULAR MOBILITY J. Biol. Chem., December 22, 2006; 281(51): 39719 - 39727. [Abstract] [Full Text] [PDF]

				Z. Xu, G. Huang, and K. V. Kandror Phosphatidylinositol 4-Kinase Type II{alpha} Is Targeted Specifically to Cellugyrin-Positive Glucose Transporter 4 Vesicles Mol. Endocrinol., November 1, 2006; 20(11): 2890 - 2897. [Abstract] [Full Text] [PDF]

				E. Gonzalez and T. E. McGraw Insulin Signaling Diverges into Akt-dependent and -independent Signals to Regulate the Recruitment/Docking and the Fusion of GLUT4 Vesicles to the Plasma Membrane Mol. Biol. Cell, October 1, 2006; 17(10): 4484 - 4493. [Abstract] [Full Text] [PDF]

				M. Mari, P. Monzo, V. Kaddai, F. Keslair, T. Gonzalez, Y. Le Marchand-Brustel, and M. Cormont The Rab4 effector Rabip4 plays a role in the endocytotic trafficking of Glut 4 in 3T3-L1 adipocytes J. Cell Sci., April 1, 2006; 119(7): 1297 - 1306. [Abstract] [Full Text] [PDF]

				A. Bose, A. Guilherme, S. Huang, A. C. Hubbard, C. R. Lane, N. A. Soriano, and M. P. Czech The v-SNARE Vti1a Regulates Insulin-stimulated Glucose Transport and Acrp30 Secretion in 3T3-L1 Adipocytes J. Biol. Chem., November 4, 2005; 280(44): 36946 - 36951. [Abstract] [Full Text] [PDF]

				L. V. Li and K. V. Kandror Golgi-Localized, {gamma}-Ear-Containing, Arf-Binding Protein Adaptors Mediate Insulin-Responsive Trafficking of Glucose Transporter 4 in 3T3-L1 Adipocytes Mol. Endocrinol., August 1, 2005; 19(8): 2145 - 2153. [Abstract] [Full Text] [PDF]

				M. Malikova, J. Shi, and K. V. Kandror V-type ATPase is involved in biogenesis of GLUT4 vesicles Am J Physiol Endocrinol Metab, September 1, 2004; 287(3): E547 - E552. [Abstract] [Full Text] [PDF]

				G. M. Belfort and K. V. Kandror Cellugyrin and Synaptogyrin Facilitate Targeting of Synaptophysin to a Ubiquitous Synaptic Vesicle-sized Compartment in PC12 Cells J. Biol. Chem., November 28, 2003; 278(48): 47971 - 47978. [Abstract] [Full Text] [PDF]