Dugina Vera, Alieva Irina, Khromova Natalya, Kireev Igor, Gunning Peter W, Kopnin Pavel
Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.
School of Medical Science, The University of New South Wales, NSW, Sydney, Australia.
Oncotarget. 2016 Nov 8;7(45):72699-72715. doi: 10.18632/oncotarget.12236.
Actin microfilaments and microtubules are both highly dynamic cytoskeleton components implicated in a wide range of intracellular processes as well as cell-cell and cell-substrate interactions. The interactions of actin filaments with the microtubule system play an important role in the assembly and maintenance of 3D cell structure. Here we demonstrate that cytoplasmic actins are differentially distributed in relation to the microtubule system. LSM, 3D-SIM, proximity ligation assay (PLA) and co-immunoprecipitation methods applied in combination with selective depletion of β- or γ-cytoplasmic actins revealed a selective interaction between microtubules and γ-, but not β-cytoplasmic actin via the microtubule +TIPs protein EB1. EB1-positive comet distribution analysis and quantification have shown more effective microtubule growth in the absence of β-actin. Our data represent the first demonstration that microtubule +TIPs protein EB1 interacts mainly with γ-cytoplasmic actin in epithelial cells.
肌动蛋白微丝和微管都是高度动态的细胞骨架成分，参与广泛的细胞内过程以及细胞间和细胞与底物的相互作用。肌动蛋白丝与微管系统的相互作用在三维细胞结构的组装和维持中起重要作用。在这里，我们证明细胞质肌动蛋白相对于微管系统呈差异分布。将激光扫描显微镜（LSM）、三维结构光照明显微镜（3D-SIM）、邻近连接分析（PLA）和免疫共沉淀方法与选择性耗尽β-或γ-细胞质肌动蛋白相结合应用，揭示了微管与γ-而非β-细胞质肌动蛋白通过微管正端追踪蛋白（+TIPs）EB1存在选择性相互作用。EB1阳性彗星分布分析和定量显示，在没有β-肌动蛋白的情况下微管生长更有效。我们的数据首次证明微管+TIPs蛋白EB1在上皮细胞中主要与γ-细胞质肌动蛋白相互作用。
