Gov N, Safran S A
Department of Chemical Physics, Weizmann Institute of Science, Rehovot, Israel.
J Biol Phys. 2005 Dec;31(3-4):453-64. doi: 10.1007/s10867-005-6472-7.
We review recent theoretical work that analyzes experimental measurements of the shape and fluctuations of red blood cells. Particular emphasis is placed on the role of the cytoskeleton and cell elasticity and we contrast the situation of elastic cells with that of fluid-filled vesicles. In red blood cells (RBCs), the cytoskeleton consists of a two-dimensional network of spectrin proteins. Our analysis of the wave vector and frequency dependence of the fluctuation spectrum of RBCs indicates that the spectrin network acts as a confining potential that reduces the fluctuations of the lipid bilayer membrane. However, since the cytoskeleton is only sparsely connected to the bilayer, one cannot regard the composite cytoskeleton membrane as a polymerized object with a shear modulus. The sensitivity of RBC fluctuations and shapes to ATP concentration may reflect the transient defects induced in the cytoskeleton network by ATP.
我们回顾了近期的理论研究工作,这些工作分析了对红细胞形状和波动的实验测量结果。特别强调了细胞骨架和细胞弹性的作用,并将弹性细胞的情况与充满流体的囊泡的情况进行了对比。在红细胞(RBC)中,细胞骨架由血影蛋白的二维网络组成。我们对红细胞波动谱的波矢和频率依赖性的分析表明,血影蛋白网络起到了限制势能的作用,减少了脂质双分子层膜的波动。然而,由于细胞骨架仅稀疏地连接到双分子层,因此不能将复合细胞骨架膜视为具有剪切模量的聚合物体。红细胞波动和形状对ATP浓度的敏感性可能反映了ATP在细胞骨架网络中诱导的瞬时缺陷。