Regensburg 2013 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 24: Posters: Physics of Cells

BP 24.24: Poster

Mittwoch, 13. März 2013, 17:30–19:30, Poster C

Dynamics of Stem Cell Stress Fibers — •Carina Wollnik¹, Ina Schachtschneider², Carsten Gottschlich², Stephan Huckemann², and Florian Rehfeldt¹ — ¹Third Institute of Physics - Biophysics, Georg-August-University, Göttingen, Germany — ²Institute for Mathematical Stochastics, Georg-August-University, Göttingen, Germany

Mechanical cues can be as important to cell behaviour as biochemical ones. Engler et al. demonstrated that varying the substrate stiffness could guide human mesenchymal stem cells (hMSCs) towards different lineages in the absence of additional biochemical cues. The complex differentiation process takes several days up to weeks, but primary characteristic changes of the cytoskeleton can be detected within the first 48 hours. Here the key players are cytoskeletal structures like stress fibers, composed of actin filaments, actin binding- and crosslinking-proteins, and non-muscle myosin motor-proteins. Stress fibers generate and transmit forces within the cell and to the extracellular matrix.

During the initial adhesion and spreading process the cell area changes as well as the cells' aspect ratio and stress fiber structure. We study the dynamics of these processes to gain a deeper understanding of the differentiation initiation steps. In our experiments we use live-cell imaging of RFP-Lifeact transfected hMSCs and trace the acto-myosin stress fibers with novel sophisticated filament tracking algorithms, which enable us to investigate the dynamics of stress fiber formation that leads to a non-monotonic dependence of stress fiber polarization on the Young's modulus of the underlying substrate.