In adherent cells, the relevance of a physical mechanotransduction pathway provided by the perinuclear actin cap stress fibers has recently emerged. Here, we investigate the impact of a functional actin cap on the cellular adaptive response to topographical cues and uniaxial cyclic strain. Lmna-deficient fibroblasts are used as a model system because they do not develop an intact actin cap, but predominantly form a basal layer of actin stress fibers underneath the nucleus. We observe that topographical cues induce alignment in both normal and Lmna-deficient fibroblasts, suggesting that the topographical signal transmission occurs independently of the integrity of the actin cap. By contrast, in response to cyclic uniaxial strain, Lmna-deficient cells show a compromised strain avoidance response, which is completely abolished when topographical cues and uniaxial strain are applied along the same direction. These findings point to the importance of an intact and functional actin cap in mediating cellular strain avoidance.
The authors declare no competing or financial interests.
C.T., J.L.V.B. and C.V.C.B. conceived the project. C.T., M.A.F.K., M.H., J.L.V.B. performed the experiments. C.T. analyzed the data. C.T. wrote the manuscript. All authors reviewed the manuscript.
This work was supported by NanoNextNL (to F.P.T.B. and C.T.).
Supplementary information available online at http://jcs.biologists.org/lookup/doi/10.1242/jcs.184838.supplemental
- Received December 11, 2015.
- Accepted December 29, 2016.
- © 2017. Published by The Company of Biologists Ltd