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arXiv · 2101.07058

Active instability and nonlinear dynamics of cell-cell junctions

Matej Krajnc·Tomer Stern·Clement Zankoc
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Abstract

Active cell-junction remodeling is important for tissue morphogenesis, yet its underlying physics is not understood. We study a mechanical model that describes junctions as dynamic active force dipoles. Their instability can trigger cell intercalations by a critical collapse. Nonlinearities in tissue's elastic response can stabilize the collapse either by a limit cycle or condensation of junction lengths at cusps of the energy landscape. Furthermore, active junction networks undergo collective instability to drive active in-plane ordering or develop a limit cycle of collective oscillations, which extends over regions of the energy landscape corresponding to distinct network topologies.

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Matej Krajnc, Tomer Stern, Clement Zankoc. 2021-10-25. Active instability and nonlinear dynamics of cell-cell junctions. https://doi.org/10.1103/physrevlett.127.198103

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