Fluctuations and conformational stability of a membrane patch with curvature inducing inclusions.
Fluctuations and conformational stability of a membrane patch with curvature inducing inclusions.
复制标题
具有曲率诱导内含物的膜片的波动和构象稳定性。
作者：
W. Pezeshkian;J. Ipsen
具有曲率诱导包裹体的膜表现出一系列与生物膜功能有关的协同现象，如膜管形成、囊泡形成、软化和自发张力。我们通过用蒙特卡罗模拟技术对一个脱汗膜模型的分析，研究了这些现象对于波动的框架膜是如何相关的。膜模型基于一个动态三角化的表面，该表面配备了非相互作用的、向上向下对称破缺的夹杂，其中只保持与平均曲率线性耦合的项。结果表明，横向构型熵对半柔性膜的力学性能起着关键作用，如在膜的中间夹杂物覆盖处发生明显的软化和膜张力的产生。无张力框架膜将保持准平坦直到一定的阈值覆盖率，其中形状不稳定随着珠光膜或管状膜的形成而发生，而珠光膜或管状膜的形成低于全覆盖率则与弯曲和平坦的膜几何形状之间的夹杂物的分离有关。对于倾向于高弯曲膜的夹杂物，不稳定出现在稀包裹体覆盖处，并伴随着强烈的构型波动。
Membranes with curvature inducing inclusions display a range of cooperative phenomena, which can be linked to biomembrane function, e.g. membrane tubulation, vesiculation, softening and spontaneous tension. We investigate how these phenomena are related for a fluctuating, framed membrane through analysis of a descretized membrane model by Monte Carlo simulation techniques. The membrane model is based on a dynamically triangulated surface equipped with non-interacting, up-down symmetry breaking inclusions where only terms coupled linearly to mean-curvature are maintained. We show that the lateral configurational entropy plays a key role for the mechanical properties of the semi-flexible membrane, e.g. a pronounced softening at intermediate inclusion coverages of the membrane and generation of membrane tension. Tensionless framed membranes will remain quasi-flat up to some threshold coverage, where a shape instability occurs with formation of pearling or tubular membranes, which below full coverage is associated with segregation of inclusions between the curved and flat membrane geometries. For inclusions with preference for highly curved membranes the instability appears at dilute inclusion coverages and is accompanied by strong configurational fluctuations.
影响因子：
17.1
作者：
Bhatia, Tripta;Agudo-Canalejo, Jaime;Lipowsky, Reinhard
通讯作者：
Lipowsky, Reinhard