Document Detail


Insulin controls the spatial distribution of GLUT4 on the cell surface through regulation of its postfusion dispersal.
MedLine Citation:
PMID:  20816091     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
While the glucose transporter-4 (GLUT4) is fundamental to insulin-regulated glucose metabolism, its dynamic spatial organization in the plasma membrane (PM) is unclear. Here, using multicolor TIRF microscopy in transfected adipose cells, we demonstrate that insulin regulates not only the exocytosis of GLUT4 storage vesicles but also PM distribution of GLUT4 itself. In the basal state, domains (clusters) of GLUT4 molecules in PM are created by an exocytosis that retains GLUT4 at the fusion site. Surprisingly, when insulin induces a burst of GLUT4 exocytosis, it does not merely accelerate this basal exocytosis but rather stimulates approximately 60-fold another mode of exocytosis that disperses GLUT4 into PM. In contradistinction, internalization of most GLUT4, regardless of insulin, occurs from pre-existing clusters via the subsequent recruitment of clathrin. The data fit a new kinetic model that features multifunctional clusters as intermediates of exocytosis and endocytosis.
Authors:
Karin G Stenkula; Vladimir A Lizunov; Samuel W Cushman; Joshua Zimmerberg
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, N.I.H., Intramural; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Cell metabolism     Volume:  12     ISSN:  1932-7420     ISO Abbreviation:  Cell Metab.     Publication Date:  2010 Sep 
Date Detail:
Created Date:  2010-09-06     Completed Date:  2010-11-04     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101233170     Medline TA:  Cell Metab     Country:  United States    
Other Details:
Languages:  eng     Pagination:  250-9     Citation Subset:  IM    
Copyright Information:
2010 Elsevier Inc. All rights reserved.
Affiliation:
Experimental Diabetes, Metabolism, and Nutrition Section, Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adipocytes / cytology,  metabolism
Animals
Caveolins / metabolism
Cell Membrane / drug effects,  metabolism*
Cells, Cultured
Clathrin / metabolism
Endocytosis / drug effects*,  physiology
Exocytosis / drug effects*,  physiology
Glucose Transporter Type 4 / genetics,  metabolism*
Insulin / pharmacology,  physiology*
Membrane Fusion / physiology*
Models, Biological
Rats
Recombinant Fusion Proteins / genetics,  metabolism
Chemical
Reg. No./Substance:
0/Caveolins; 0/Clathrin; 0/Glucose Transporter Type 4; 0/Recombinant Fusion Proteins; 11061-68-0/Insulin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Interleukin-6 signaling in liver-parenchymal cells suppresses hepatic inflammation and improves syst...
Next Document:  Insulin-like signaling determines survival during stress via posttranscriptional mechanisms in C. el...