Aarhus Universitets segl

Genetic disruption of calpain correlates with loss of membrane blebbing and differential expression of RhoGDI-1, cofilin and tropomyosin

Publikation: Bidrag til tidsskrift/Konferencebidrag i tidsskrift /Bidrag til avisTidsskriftartikelForskningpeer review

  • Anna K Larsen, Københavns Universitet, Danmark
  • René Lametsch, Københavns Universitet, Danmark
  • John S Elce, Department of Biochemistry, Queen's University, Storbritannien
  • Jørgen K Larsen, Københavns Universitet, Danmark
  • Bo Thomsen
  • Martin R Larsen, Syddansk Universitet, Danmark
  • Moira A Lawson, Københavns Universitet, Danmark
  • Peter A Greer, Queen's University, Storbritannien
  • Per Ertbjerg, Københavns Universitet, Danmark
  • Institut for Genetik og Bioteknologi
  • Molekylær Genetik og Systembiologi
 Dynamic regulation of the actin cytoskeleton is important for cell motility, spreading and the formation of membrane surface extensions such as lamellipodia, ruffles and blebs. The ubiquitous calpains contribute to integrin-mediated cytoskeletal remodelling during cell migration and spreading, by cleavage of focal adhesion components and signalling molecules. In the present study, the live-cell morphology of calpain-knockout and wild-type cells was examined by time-lapse fluorescence microscopy, and a role of calpain in mediating the formation of sporadic membrane blebs was established. Membrane blebbing was significantly reduced in calpain-knockout cells, and genetic rescue fully restored the wild-type phenotype in knockout cells. Proteomic comparison of wild-type and knockout cells identified decreased levels of RhoGDI-1 (Rho GDP-dissociation inhibitor) and cofilin 1, and increased levels of tropomyosin in calpain-knockout cells, suggesting a role of calpain in regulating membrane extensions involving these proteins. RhoGDI, cofilin and tropomyosin are known regulators of actin filament dynamics and membrane extensions. The reduced levels of RhoGDI-1 in calpain-knockout cells observed by proteome analysis were confirmed by immunoblotting. Genetic rescue of the calpain-knockout cells enhanced RhoGDI-1-expression 2-fold above that normally present in wild-type cells. These results suggest a regulatory connection between calpain and RhoGDI-1 in promoting formation of membrane blebs
TidsskriftBiochemical Journal
Sider (fra-til)657-666
StatusUdgivet - 2008

Se relationer på Aarhus Universitet Citationsformater

ID: 1202768