Biology Reference
In-Depth Information
limited. The findings from our laboratory and other laboratories support a
critical role for the calcium-dependent protease calpain during migration and
in the regulation of integrin-containing adhesive contact sites. It is likely that
the effects of calpain on cell motility are to a large extent mediated by its
effects on the composition and organization of focal adhesions. However, how
the irreversible modification of substrates by calpain participates in
intracellular signalling and the dynamic regulation of cell motility remains a
challenge. The tight regulation of its activity with only localized activation is
likely to be critical for its participation in cell migration. Its activation is likely
to be required for cell motility and cell retraction, while at the same time
critical for mediating stop signals that inhibit the protrusion machinery and
cell movement. The different roles of calpain in the migration of fibroblasts
and neutrophils underlie the complexity of its regulation and participation
during cell migration. The coming years promise to be informative and
exciting as we gain understanding of how migration is regulated, both
temporally and spatially, and how mediators such as calpain participate in this
regulation.
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