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arXiv · 2006.16155

A parabolic free boundary problem arising in a model of cell polarization

Abstract

The amplification of an external signal is a key step in direction sensing of biological cells. We consider a simple model for the response to a time-depending signal, which was previously proposed by the last three authors. The model consists of a bulk-surface reaction-diffusion model. We prove that in a suitable asymptotic limit the system converges to a bulk-surface parabolic obstacle type problem. For this model and a reduction to a nonlocal surface equation we show an L1-contraction property and, in the case of time-constant signals, the stability of stationary states.

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BibTeXRIS

Anna Logioti, Barbara Niethammer, Matthias Röger, Juan J. L. Velázquez. 2020-06-29. A parabolic free boundary problem arising in a model of cell polarization. https://arxiv.org/abs/2006.16155

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