%0 Generic
%A Heil, Patrick
%D 2007
%F heidok:7866
%K focal adhesion , shear load , mechanosensitivity , micromanipulation , mechanotransduction
%R 10.11588/heidok.00007866
%T Shearing Cells with Single Elastic Micropillars to Influence Focal Adhesion Dynamics
%U https://archiv.ub.uni-heidelberg.de/volltextserver/7866/
%X Focal adhesions (FAs) are important adhesion sites between eukaryotic cells and the extracellular matrix: They mediate cell adhesion, spreading and motility. Over the last decade it has become evident that FAs are bi-directional mechano-chemical devices: They both exert and sense physical forces by converting biochemical signals into mechanical force and vice versa. As such, they represent a highly fascinating interface between physics and biology. Recently, it has been shown that the intrinsic force generated by the contractile machinery of the cell that leads to FA growth can be substituted by external forces. However, the exact mechanism behind FA-mediated mechanosensing remained unclear. This unsolved question has stimulated several competing theories that attempt to model the physical principles governing the force-induced assembly of adhesion plaque proteins. In this thesis, we present a novel, inexpensive method to micromanipulate living cells with single elastic micropillars and discuss the effect of lateral shear stress on focal adhesion dynamics of fibroblasts. We have successfully induced both growth and disassembly of FAs by shearing cells. Dynamics of single FAs and intensity profiles along their major axes have been analyzed in detail. We find distinct features for stretched respectively relaxed FAs. The presented data will be valuable for the further refinement, verification or falsification of theories in this field.