Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 24: Actin Dynamics

BP 24.4: Vortrag

Donnerstag, 28. Februar 2008, 15:00–15:15, C 243

Actin flow and cellular traction at focal adhesions: measurements and theoretical interpretation — •Benedikt Sabass¹, Margaret Gardel², Clare Waterman³, and Ulrich Schwarz¹ — ¹University of Heidelberg, BQ 0013, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany — ²University of Chicago, IL, USA — ³NIH, Bethesda, MD, USA

The dynamic nature of cell-substrate contacts (focal adhesions) is an essential ingredient of the communication between cells and their environment. In particular the intracellular motion of actin flow and its connection to external cellular traction seems to be crucial for cellular decision making at focal adhesions. We have developed a novel assay to simultaneously measure retrograde actin flow and cellular traction force with high spatial resolution. The resulting data demonstrates a biphasic relationship between actin speed and traction. Moreover, we find that maximum traction is always exerted at a speed level which is independent of biochemical perturbations. This suggests the existence of a robust sensory mechanism relating internal flow dynamics to traction in the environment. We also discuss physical models for bond dynamics which are able to explain the experimentally found data.