Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA, United Kingdom.
Wellcome Trust / CRUK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, United Kingdom.
Phys Rev Lett. 2020 Oct 2;125(14):148102. doi: 10.1103/PhysRevLett.125.148102.
How does a cell locate the source of molecular guidance cues from within a concentration gradient? We present a computational approach to recover the source from the absorbed fluxes at narrow receptor windows located on the surface of the cell. In the limit of fast binding, we solve the steady-state diffusion equation using an asymptotic approach and hybrid stochastic-analytical simulations. We show that the sensitivity to the gradient direction decays too rapidly to enable long-distance sensing. We illustrate how this constraint can be alleviated when triangulating the source with an increasing number of receptor windows and quantify the susceptibility of this process to flux perturbations.
细胞如何从浓度梯度内定位分子导向线索的来源？我们提出了一种从位于细胞表面的窄受体窗口处吸收的通量中恢复来源的计算方法。在快速结合的极限下，我们使用渐近方法和混合随机分析模拟来求解稳态扩散方程。我们表明，对梯度方向的敏感性衰减得太快，无法实现远距离感应。我们说明了如何在用越来越多的受体窗口对源进行三角剖分的情况下缓解这种约束，并量化了该过程对通量干扰的敏感性。
