Mechanical stimulation of C2C12 cells increases m-calpain expression, focal adhesion plaque protein degradation

Research output: Contribution to journalJournal articleResearchpeer-review

  • Alberto Grossi
  • Anders H Karlsson
  • Moira Ann Lawson
Myogenesis is a complex sequence of events, including the irreversible transition from the proliferation-competent myoblast stage into fused, multinucleated myotubes. During embryonic development, myogenic differentiation is regulated by positive and negative signals from surrounding tissues. Stimulation due to stretch- or load-induced signaling is now beginning to be understood as a factor which affects gene sequences, protein synthesis and an increase in Ca2+ influx in myocytes. Evidence of the involvement of Ca2+ -dependent activity in myoblast fusion, cell membrane and cytoskeleton component reorganization due to the activity of the ubiquitous proteolytic enzymes, calpains, has been reported. Whether there is a link between stretch- or load-induced signaling and calpain expression and activation is not known. Using a magnetic bead stimulation assay and C2C12 mouse myoblasts cell population, we have demonstrated that mechanical stimulation via laminin receptors leads to an increase in m-calpain expression, but no increase in the expression of other calpain isoforms. Our study revealed that after a short period of stimulation, m-calpain relocates into focal adhesion complexes and is followed by a breakdown of specific focal adhesion proteins previously identified as substrates for this enzyme. We show that stimulation also leads to an increase in calpain activity in these cells. These data support the pivotal role for m-calpain in the control of muscle precursor cell differentiation and thus strengthen the idea of its implication during the initial events of muscle development.
Original languageEnglish
JournalCell Biology International
Volume32
Issue number6
Pages (from-to)615-622
Number of pages8
ISSN1065-6995
DOIs
Publication statusPublished - 2008

Bibliographical note

Keywords: Animals; Calpain; Cell Line; Cell Membrane; Focal Adhesions; Mechanotransduction, Cellular; Mice; Myoblasts; Paxillin; Talin

ID: 5240945