Mechanosensing in actin stress fibers revealed by a close correlation between force and protein localization

Title data

Colombelli, Julien ; Besser, Achim ; Kress, Holger ; Reynaud, Emmanuel G. ; Girard, Philippe ; Caussinus, Emmanuel ; Haselmann, Uta ; Small, John V. ; Schwarz, Ulrich S. ; Stelzer, Ernst H. K.:
Mechanosensing in actin stress fibers revealed by a close correlation between force and protein localization.
In: Journal of Cell Science. Vol. 122 (2009) Issue 10 . - pp. 1665-1679.
ISSN 1477-9137
DOI: https://doi.org/10.1242/jcs.042986

Official URL:

Abstract in another language

The mechanics of the actin cytoskeleton have a central role in the regulation of cells and tissues, but the details of how molecular sensors recognize deformations and forces are elusive. By performing cytoskeleton laser nanosurgery in cultured epithelial cells and fibroblasts, we show that the retraction of stress fibers (SFs) is restricted to the proximity of the cut and that new adhesions form at the retracting end. This suggests that SFs are attached to the substrate. A new computational model for SFs confirms this hypothesis and predicts the distribution and propagation of contractile forces along the SF. We then analyzed the dynamics of zyxin, a focal adhesion protein present in SFs. Fluorescent redistribution after laser nanosurgery and drug treatment shows a high correlation between the experimentally measured localization of zyxin and the computed localization of forces along SFs. Correlative electron microscopy reveals that zyxin is recruited very fast to intermediate substrate anchor points that are highly tensed upon SF release. A similar acute localization response is found if SFs are mechanically perturbed with the cantilever of an atomic force microscope. If actin bundles are cut by nanosurgery in living Drosophila egg chambers, we also find that zyxin redistribution dynamics correlate to force propagation and that zyxin relocates at tensed SF anchor points, demonstrating that these processes also occur in living organisms. In summary, our quantitative analysis shows that force and protein localization are closely correlated in stress fibers, suggesting a very direct force-sensing mechanism along actin bundles.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Institutions of the University:	Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Physics > Professor Experimental Physics VI - Biologial Physics > Professor Experimental Physics VI - Biologial Physics - Univ.-Prof. Dr. Holger Kreß Faculties Faculties > Faculty of Mathematics, Physics und Computer Science Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Physics Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Physics > Professor Experimental Physics VI - Biologial Physics
Result of work at the UBT:	No
DDC Subjects:	500 Science > 530 Physics 500 Science > 570 Life sciences, biology
Date Deposited:	26 Feb 2021 09:06
Last Modified:	29 Jun 2022 14:49
URI:	https://eref.uni-bayreuth.de/id/eprint/63441