Papel de las caveolas/caveolina-1 en la fisiologia del adipocito

by González Muñoz, Elena

Abstract (Summary)
ENGLISH SUMMARY: Caveolae are a specialized type of lipid rafts that are stabilized by oligomers of caveolin protein. Caveolae are particularly enriched in adipocytes. Here we analyzed the effects of caveolin-1 knockdown and caveolae ablation on adipocyte function. To this end, we obtained several multiclonal mouse 3T3-L1 cell lines with a reduced expression of caveolin-1 (95% reduction) by a small interfering RNA approach using lentiviral vectors. Control cell lines were obtained by lentiviral infection with lentiviral vectors encoding appropriate scrambled RNAs. Caveolin-1 knockdown adipocytes showed a drastic reduction in the number of caveolae (95% decrease) and cholera toxin-labeling was reorganized in dynamic plasma membrane microdomains. Caveolin-1 depletion caused a specific decrease in GLUT4 glucose transporter and insulin receptor protein levels. This reduction was not the result of a generalized defect in adipocyte differentiation or altered gene expression but was explained by faster degradation of these proteins. Caveolin-1 knockdown adipocytes showed reductions in insulin-stimulated glucose transport, insulin-triggered GLUT4 recruitment to the cell surface and insulin receptor activation. In all, our data indicate that caveolin-1 loss-of-function reduces maximal insulin response through lowered stability and diminished expression of insulin receptors and GLUT4. We propose that caveolin-1/caveolae control insulin action in adipose cells.
This document abstract is also available in Spanish.
Bibliographical Information:

Advisor:Camps Camprubí, Maria; Zorzano Olarte, Antonio

School:Universitat de Barcelona

School Location:Spain

Source Type:Master's Thesis

Keywords:bioquímica i biologia molecular fac


Date of Publication:11/28/2007

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