Send to

Choose Destination
See comment in PubMed Commons below
J Cell Sci. 2002 Sep 1;115(Pt 17):3415-25.

Regulation of focal complex composition and disassembly by the calcium-dependent protease calpain.

Author information

Department of Pediatrics and Pharmacology, University of Wisconsin, 1300 University Avenue, University of Wisconsin Medical School, Madison, WI 53706, USA.


Cell migration requires the regulated and dynamic turnover of adhesive complexes. We have previously demonstrated that the calcium-dependent protease, calpain, regulates the organization of adhesive complexes and cell detachment during cell migration. Evidence is now provided that inhibiting calpain through over-expression of the endogenous inhibitor of calpain, calpastatin, and pharmacological inhibitors results in an inhibition of adhesive complex disassembly with stabilization of GFP-vinculin and GFP/RFP-zyxin at the cell periphery. Calpain was also required for the microtubule-mediated turnover of adhesive complex sites after nocodazole wash-out, suggesting that calpain may mediate focal complex disassembly downstream of microtubules. Using dual imaging of RFP-zyxin and GFP-alpha-actinin, we observed a temporal and spatial relationship between alpha-actinin localization to focal contacts and the subsequent disassembly or translocation of RFP-zyxin containing focal complexes in areas of cell retraction. Calpain inhibition disrupted alpha-actinin localization to zyxin-containing focal contacts and focal complex disassembly or translocation to the cell center. In addition, disrupting alpha-actinin localization to focal complexes through expression of the alpha-actinin rod domain, but not the head domain, resulted in inhibition of focal adhesion disassembly similar to calpain inhibition. Our studies suggest a novel mechanism of action whereby calpain may modulate alpha-actinin localization into focal complexes and their subsequent disassembly or translocation.

[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center