Comparative proteomic analysis of myotube caveolae after milli-calpain deregulation.
Caveolae are specialised RAFTs (detergent-resistant membrane microdomains enriched in cholesterol and glycosphingolipids). Caveolin, the main caveolae protein, is essential to the organisation of proteins and lipids, and interacts with numerous mediating proteins through a 'Caveolin Scalfolding Domain'. Consequently, caveolae play a major role in signal transduction and appear to be veritable signalling platforms. In muscle cells, caveolae are essential for fusion and differentiation, and are also implicated in a type of muscular dystrophy (LGMD1C). In a preceding work, we demonstrated the presence of active milli-calpain (m-calpain) in myotube caveolae. Calpains are calcium-dependent proteases involved in several cellular processes, including myoblast fusion and migration, PKC-mediated intracellular signalling and remodelling of the cytoskeleton. For the first time, we have proved the cholesterol-dependent localisation of m-calpain in the caveolae of C(2)C(12) myotubes. Calpain-dependent caveolae involvement in myoblast fusion was also strongly suggested. Furthermore, eight differentially expressed caveolae associated proteins were identified by 2-DE and LC-MS/MS analyses using an m-calpain antisense strategy. This proteomic study also demonstrates the action of m-calpain on vimentin, desmin and vinculin in myotube caveolae and suggests m-calpain's role in several mitochondrial pathways.
Goudenege
Sébastien
S
Université Bordeaux I, USC-INRA 2009, Unité Protéolyse, Croissance et Développement Musculaire, ISTAB, Talence, France.
Dargelos
Elise
E
Claverol
Stéphane
S
Bonneu
Marc
M
Cottin
Patrick
P
Poussard
Sylvie
S
D000595:Amino Acid Sequence; D001483:Base Sequence; D015153:Blotting, Western; D002154:Calpain / Q000378:metabolism*; D021941:Caveolae / Q000378:metabolism*; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D018485:Muscle Fibers, Skeletal / Q000187:drug effects / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism; D020543:Proteome; D016372:RNA, Antisense / Q000494:pharmacology; D015398:Signal Transduction; D053719:Tandem Mass Spectrometry
D020543:Proteome; D016372:RNA, Antisense; D011493:Protein Kinase C; D002154:Calpain