Mechanical stimuli on C2C12 myoblasts affect myoblast differentiation, focal adhesion kinase phosphorylation and galectin-1 expression: a proteomic approach

Mechanical forces are crucial in the regulation of cell morphology and function. At the cellular level, these forces influence myoblast differentiation and fusion. In this study, we applied mechanical stimuli to embryonic muscle cells using magnetic microbeads, a method shown to apply stress to specific receptors on the cell surface. We showed that mechanical stimuli promote an increase in FAK (focal adhesion kinase) phosphorylation. In order to further shed light in the process of myoblast-induced differentiation by mechanical stimuli, we performed a proteomic analysis. Thirteen proteins were found to be affected by mechanical stimulation including galectin-1, annexin III and RhoGDI (Rho guanine-nucleotide-dissociation inhibitor). In this study, we demonstrate how the combination of this method of mechanical stimuli and proteomic analysis can be a powerful tool to detect proteins that are potentially interacting in biochemical pathways or complex cellular mechanisms during the process of myoblast differentiation. We determined an increase in expression and changes in cellular localization of galectin-1 in mechanically stimulated myoblasts. A potential involvement of galectin-1 in myoblast differentiation is presented.