Dresden 2017 – wissenschaftliches Programm
CPP 14.7: Poster
Montag, 20. März 2017, 18:30–21:00, P1C
Actin stress fiber dynamics under lateral constraint — •Andreas Müller and Tilo Pompe — Universität Leipzig, Institute of Biochemistry, Johannisallee 21-23, 04103 Leipzig
Cells at interfaces experience inhomogeneous mechanical environments, including spatial constraints, even down to 1D confinement, e.g., on single fibers in reconstituted in vitro fibrous scaffolds and also in various tissues in vivo. Previously, we found a bimodal distribution of actin stress fibers in cells under varying lateral constraint, indicated by the distinct formation of exterior and interior stress fibers and their respective spacing. We now investigated the dynamics of stress fiber formation and the correlated cell traction forces.
We use micro-patterned hard substrates and polyacrylamide hydrogels with fibronectin for subsequent culture of cells on stripe-like patterns. Cells are analyzed for several hours using SiR-Actin probes, focusing on actin cytoskeleton pattern, overall cell characteristics, and cell traction forces. We show that the magnitude of traction forces does correlate weakly with lateral constraint while actin cytoskeleton morphology and directionality of traction forces are strongly correlated and governed by the degree of confinement. Furthermore, time resolved actin stress fiber patterns are investigated in relation to cell dynamics.
With our setup, we are able to determine the mechanical and morphological response of cells in spatially constraining environments in a time-resolved manner.