A calcium-mediated actin reset (CaAR) acutely regulates cell cortex activity

Speaker: Professor Roland Wedlich-Söldner, University of Münster

Host: Snezhka Oliferenko

Abstract: In the context of widespread interdependence, competition and mechanical connectivity between cytoskeletal assemblies, cells face formidable challenges when undergoing global morphological reorganizations. We have recently shown that mammalian cells reset their actin cytoskeleton in response to acute calcium-mediated stress signals. Activated by calcium influx, the formin INF2 stimulates filament polymerization at the endoplasmic reticulum (ER) while cortical actin is disassembled. This Calcium-mediated actin reset (CaAR) occurs in a wide range of mammalian cell types. CaAR leads to transient immobilization of organelles and drives the reorganization of actin during cell cortex repair, cell spreading and wound healing. Our findings suggest that CaAR acts as a fundamental facilitator of cellular adaptations in response to acute signals during stress and inflammation. I will present our latest results on the molecular mechanisms driving CaAR, and its implications for cell physiology and disease.