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arXiv · 1411.2258

Propagating stress waves during epithelial expansion

Shiladitya Banerjee·Kazage J. C. Utuje·M. Cristina Marchetti
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Abstract

Coordinated motion of cell monolayers during epithelial wound healing and tissue morphogenesis involves mechanical stress generation. Here we propose a model for the dynamics of epithelial expansion that couples mechanical deformations in the tissue to contractile activity and polarization in the cells. A new ingredient of our model is a feedback between local strain, polarization and contractility that naturally yields a mechanism for viscoelasticity and effective inertia in the cell monolayer. Using a combination of analytical and numerical techniques, we demonstrate that our model quantitatively reproduces many experimental findings [Nat. Phys. 8, 628 (2012)], including the build-up of intercellular stresses, and the existence of traveling mechanical waves guiding the oscillatory monolayer expansion.

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Shiladitya Banerjee, Kazage J. C. Utuje, M. Cristina Marchetti. 2014-11-09. Propagating stress waves during epithelial expansion. https://doi.org/10.1103/physrevlett.114.228101

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