Simulations of the erythrocyte cytoskeleton at large deformation. II. Micropipette aspiration
Simulations of the erythrocyte cytoskeleton at large deformation. II. Micropipette aspiration
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DOI：
10.1016/s0006-3495(98)74076-7
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发表时间：
1998-09-01
影响因子：
3.4
通讯作者：
Boey, SK
中科院分区：
文献类型：
--
作者：
Discher, DE;Boal, DH;Boey, SK
粗粒度的红细胞膜的血影蛋白细胞骨架的分子模型中提出的Monte Carlo模拟在微管抽吸的整个细胞。在更微观的细胞骨架模型中揭示了非线性链弹性和空间位阻（在配套论文中开发; Boey等人，1998. Biophys. J. 75：1573-1583）在这里忠实地由两体和三体有效势表示。系统的自由度的数量由此减少到计算上易处理的范围。三个有效的模型的三角形的细胞骨架的开发：两个模型中的细胞骨架是无应力的，没有或没有内部的吸引力的相互作用，和第三个模型中的细胞骨架是预应力原位。这些都是采用直接，有限温度模拟红细胞变形的微量吸管。所有这三种模型都显示出与松弛的人红细胞上进行的抽吸测量的合理一致性，但是单独的预应力模型产生与荧光成像实验的最佳一致性。因此，显示各向异性应变的非轴对称，变形结构的整体平均提供了一个基本问题的答案，如红细胞细胞骨架的三角网格在实验中变形。
Coarse-grained molecular models of the erythrocyte membrane's spectrin cytoskeleton are presented in Monte Carlo simulations of whole cells in micropipette aspiration. The nonlinear chain elasticity and sterics revealed in more microscopic cytoskeleton models (developed in a companion paper; Boey et al,, 1998. Biophys. J. 75:1573-1583) are faithfully represented here by two- and three-body effective potentials. The number of degrees of freedom of the system are thereby reduced to a range that is computationally tractable. Three effective models for the triangulated cytoskeleton are developed: two models in which the cytoskeleton is stress-free and does or does not have internal attractive interactions, and a third model in which the cytoskeleton is prestressed in situ. These are employed in direct, finite-temperature simulations of erythrocyte deformation in a micropipette. All three models show reasonable agreement with aspiration measurements made on flaccid human erythrocytes, but the prestressed model alone yields optimal agreement with fluorescence imaging experiments. Ensemble-averaging of nonaxisymmetrical, deformed structures exhibiting anisotropic strain are thus shown to provide an answer to the basic question of how a triangulated mesh such as that of the red cell cytoskeleton deforms in experiment.