Mechanics of microtubules: effects of protofilament orientation.
Mechanics of microtubules: effects of protofilament orientation.
复制标题
微管力学：原丝取向的影响。
DOI：
10.1016/j.bpj.2010.06.065
复制
发表时间：
2010
影响因子：
3.4
通讯作者：
Binka,EdemC
中科院分区：
文献类型：
--
作者：
Donhauser,ZacharyJ;Jobs,WilliamB;Binka,EdemC
微管是微管蛋白的中空圆柱形聚合物，在真核细胞中发挥许多重要的动力学和结构作用。体内和体外微管都可以以几种可能的构型存在，不同的是原丝的数量、微管蛋白二聚体的螺旋上升和相对于主管轴的原丝偏斜角。在这里，有限元建模应用于检查几个已知的微管类型时，受到径向变形的机械响应。这里提出的数据提供了一个重要的洞察微管刚度和显示，原丝取向不影响径向刚度。相反，刚度主要取决于聚合材料的有效杨氏模量和微管的有效半径。这些结果也直接相关的原子力显微镜纳米压痕测量，使以前的实验更详细的解释。当与实验数据相结合，显示出一个显着的差异稳定的微管与缓慢水解的GTP类似物和微管稳定与紫杉醇，有限元数据表明，紫杉醇增加了整体的径向灵活性的微管壁。
Microtubules are hollow cylindrical polymers of the protein tubulin that play a number of important dynamic and structural roles in eukaryotic cells. Both in vivo and in vitro microtubules can exist in several possible configurations, differing in the number of protofilaments, helical rise of tubulin dimers, and protofilament skew angle with respect to the main tube axis. Here, finite element modeling is applied to examine the mechanical response of several known microtubule types when subjected to radial deformation. The data presented here provide an important insight into microtubule stiffness and reveal that protofilament orientation does not affect radial stiffness. Rather, stiffness is primarily dependent on the effective Young's modulus of the polymerized material and the effective radius of the microtubule. These results are also directly correlated to atomic force microscopy nanoindentation measurements to allow a more detailed interpretation of previous experiments. When combined with experimental data that show a significant difference between microtubules stabilized with a slowly hydrolyzable GTP analog and microtubules stabilized with paclitaxel, the finite element data suggest that paclitaxel increases the overall radial flexibility of the microtubule wall.