Biophysical Society Thematic Meeting| Aussois 2019

Biology and Physics Confront Cell-Cell Adhesion

Poster Abstracts

4-POS Board 4 CELLULAR ADHESION DYMAMICS UNDER AN EXTERNAL FORCE Kristian Blom 1 ; Aljaz Godec 1 ; 1 Max-Planck-Institute for Biophysical Chemistry, Theoretical and Computational Biophysics, Goettingen, Germany Most of our current understanding about cellular adhesion dynamics derives from the theory of non-interacting receptor-ligand adhesion pairs. However, recent experiments have revealed collective properties of adhesion clusters, which arise from a coupling of nearby individual adhesion bonds through deformations of the fluctuating membrane. So far it is remains unclear how this coupling affects the dynamics of cluster formation and dissolution, which yields a fundamental question to be answered. In order to arrive at a deeper understanding of adhesion cluster dynamics under an external force, we incorporated both the coupling of adhesion bonds due to membrane fluctuations as well as an external force into a theory of adhesion cluster stability on a mesoscopic scale. With this model we provide rigorous results for the depinning time statistics, i.e. the time to complete cluster dissolution, for various initial geometries. Furthermore, by calculating the splitting probabilities for different cluster dissolution mechanisms, we provide a dynamical phase diagram for the path taken to the dissolved state. Our results reveal that both the depinning time statistics and cluster dissolution mechanism depend non-trivially on the coupling, the external force, and initial geometry, thereby providing deeper insight on the manner that cells could actively control their binding strength.

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