Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
AKB: Biologische Physik
AKB 13: Cell Adhesion II
AKB 13.1: Vortrag
Dienstag, 28. März 2006, 14:30–14:45, ZEU 260
Redistributing intracellular stress with biofunctionalized PDMS pillars to investigate the force induced growth of Focal Adhesions — •Patrick Heil1,2, Achim Besser1,2, and Joachim Spatz1,2 — 1Max-Planck-Institute for Metals Research, Heisenbergstr. 3, 70569 Stuttgart, Germany — 2Dept. Biophysical Chemistry, University of Heidelberg, INF 253, 69120 Heidelberg, Germany
Focal contacts (FCs) are important adhesion sites between eukaryotic cells and the extracellular matrix. The development of FCs is substrate dependent: they grow more favorably on stiffer substrates than on soft ones. A deeper insight into this observed cellular mechanosensitivity is crucial to understand the role of FCs in cell adhesion and motility. To quantitatively study this mechanosensitivity and the stimulation of FC growth, microfabricated arrays of elastic polymer pillars are used to manipulate the FC assembly of rat fibroblasts: We use cell-attached micropillars to apply lateral force to the Focal Adhesion sites.
The micropillars are specifically biofunctionalized with ligands such as fibronectin that are known to stimulate cell adhesion. Furthermore, they can be used as force sensors to monitor the applied lateral force in real time. The cells, fibroblasts transfected to express YFP-labeled Paxilin, are maintained in favorable conditions, allowing live imaging of FCs over extended periods of time. Thus, the resultant growth rate of FCs versus applied force can be systematically measured.
We also present a theoretical model to explain force dependent growth of FCs. This model is based on the interplay between an elastic equation for the plaque of FC proteins and the dynamics of protein adsorption.