A direct interaction between actin and vimentin filaments mediated by the tail domain of vimentin
A direct interaction between actin and vimentin filaments mediated by the tail domain of vimentin
复制标题
DOI：
10.1074/jbc.m605452200
复制
发表时间：
2006-10-13
影响因子：
4.8
通讯作者：
Wirtz, Denis
中科院分区：
文献类型：
--
作者：
Esue, Osigwe;Carson, Ashley A.;Wirtz, Denis
肌动蛋白、微管和中间丝这三种主要真核细胞骨架蛋白的组装和组织是高度相互依赖的。通过进化，细胞已经发展出了专门的多功能蛋白质，这些蛋白质介导了这些细胞骨架细丝网络的交叉连接。在这里，我们测试了两个丝状蛋白，F-肌动蛋白和波形蛋白细丝，可以直接相互作用的假设，即在没有辅助蛋白的情况下。通过定量流变学研究，我们发现，波形蛋白/肌动蛋白细丝网络的刚性显著高于只含有肌动蛋白细丝或仅含有波形蛋白细丝的网络。当波形蛋白/肌动蛋白的摩尔比为3：1时，纤维间的相互作用最大。肌动蛋白和无尾波形蛋白纤维的混合网络显示出较低的机械硬度和较弱的纤维间相互作用。再加上具有显著的波形蛋白和肌动蛋白网络的细胞比缺乏有组织的肌动蛋白或波形蛋白网络的细胞要坚硬得多，这些结果表明，肌动蛋白和波形蛋白细丝可以直接通过波形蛋白的尾部结构域相互作用，这些细丝之间的相互作用可能有助于细胞的整体机械完整性和介导细胞骨架的串扰。
The assembly and organization of the three major eukaryotic cytoskeleton proteins, actin, microtubules, and intermediate filaments, are highly interdependent. Through evolution, cells have developed specialized multifunctional proteins that mediate the cross-linking of these cytoskeleton filament networks. Here we test the hypothesis that two of these filamentous proteins, F-actin and vimentin filament, can interact directly, i.e. in the absence of auxiliary proteins. Through quantitative rheological studies, we find that a mixture of vimentin/actin filament network features a significantly higher stiffness than that of networks containing only actin filaments or only vimentin filaments. Maximum inter-filament interaction occurs at a vimentin/actin molar ratio of 3 to 1. Mixed networks of actin and tailless vimentin filaments show low mechanical stiffness and much weaker inter-filament interactions. Together with the fact that cells featuring prominent vimentin and actin networks are much stiffer than their counterparts lacking an organized actin or vimentin network, these results suggest that actin and vimentin filaments can interact directly through the tail domain of vimentin and that these inter-filament interactions may contribute to the overall mechanical integrity of cells and mediate cytoskeletal cross-talk.