CSB Seminar: Prof. Sergey Plotnikov, Cell & Systems Biology, University of Toronto

CSB Departmental Seminar

Prof. Sergey Plotnikov
Cell and Systems Biology
University of Toronto

“Integration of Two Distinct Actin Networks by Focal Adhesions Mediates Cellular Mechanosensing”

Abstract:

Eukaryotic cells sense the mechanical properties of their microenvironment to control a wide variety of physiological functions, including cell survival, proliferation, differentiation, and migration. Recently, much emphasis has been placed on understanding the molecular mechanisms of cell mechanosensing via integrin-based focal adhesions. However, how the actin cytoskeleton, a dynamic network that generates mechanical tension and transmits it to the focal adhesions, contributes to cell mechanosensing remains largely unknown. By combining live-cell imaging, pharmacological perturbations and mathematical modeling, we deciphered the contribution of two functionally distinct actin-based domains, branched actin network and stress fibers, in mechanosensing. We further identified a specific negative feedback between formin-mediated stress fiber elongation and actomyosin contractility that drives dynamics of traction force in focal adhesions and determines range of ECM stiffness sensed by a cell. These findings demonstrate that both lamellipodia and lamellar actin networks mechanically integrated by focal adhesions are critical for mechanosensitive cellular response.

Host: Prof. Maurice Ringuette

Video Conferencing at UTM (DV 4001) & UTSc (MW 229)