Interactions of anisotropic inclusions on a fluid membrane
Interactions of anisotropic inclusions on a fluid membrane
复制标题
流体膜上各向异性夹杂物的相互作用
DOI：
10.1137/20m1332694
复制
发表时间：
2020
影响因子：
1.9
通讯作者：
and Chapman S. J.
中科院分区：
文献类型：
--
作者：
Kwiecinski;J. A.;Goriely;A.;and Chapman S. J.
生物细胞和膜需要适当地成形以实现许多基本功能。这种成形通常是由膜结合蛋白质的聚集来帮助的，这些蛋白质既能感知膜的曲率，又能对其进行成形。因此，这些蛋白质内含物通过它们影响的膜的变形而相互作用，关键问题是理解支配它们相互作用的规律。虽然各向同性蛋白质的理论情况是很好理解的，许多这样的蛋白质的一个重要特征是它们与膜的各向异性相互作用。 在这里，我们推导出一个相互作用的法律刚性圆形膜夹杂物施加各向异性的接触角周围的膜。我们包括膜弯曲和张力的影响。 利用渐近分析，我们确定了两个区别的极限分别对应于弱各向异性/弱张力和强各向异性/强张力。由此产生的法律表现出双稳态的平衡分离的夹杂物。具有非常弱的各向异性的夹杂物与大分离平衡，具有非常强的各向异性的夹杂物与小分离平衡，而存在一个各向异性范围，对于该范围，两种平衡都是稳定的。 我们的研究结果提供了一个理论机制，在实验和模拟中看到的全球聚集的夹杂物。
Biological cells and membranes need to be properly shaped to fulfill many fundamental functions. This shaping is often aided by the aggregation of membrane-bound proteins that both sense the membrane curvature and shape it. Therefore, these protein inclusions interact with each other through the deformation of the membrane that they influence, and a key question is to understand the law that governs their interaction. Whereas the theoretical case of isotropic proteins is well understood, an important feature of many such proteins is their anisotropic interaction with the membrane. Here, we derive an interaction law for rigid circular membrane inclusions which impose an anisotropic contact angle on the surrounding membrane. We include the effects of both membrane bending and tension. Using asymptotic analysis, we identify two distinguished limits corresponding to weak anisotropy/weak tension and strong anisotropy/strong tension, respectively. The resulting laws exhibit a bistability in the equilibrium separation of inclusions. Inclusions with very weak anisotropy equilibrate with large separation, those with very strong anisotropy equilibrate with small separation, while there is a range of anisotropies for which both equilibria are stable. Our results provide a theoretical mechanism for the global aggregation of inclusions seen both in experiments and simulations.