Institut Curie, PSL Research University, CNRS, UMR 144, Molecular Mechanisms of Intracellular Transport, F-75005, Paris, France.
Institut Curie, PSL Research University, CNRS, UMR 144, Structural Motility, F-75005, Paris, France.
Nat Commun. 2017 Nov 1;8(1):1254. doi: 10.1038/s41467-017-01266-0.
The actin and microtubule cytoskeletons play important roles in Golgi structure and function, but how they are connected remain poorly known. In this study, we investigated whether RAB6 GTPase, a Golgi-associated RAB involved in the regulation of several transport steps at the Golgi level, and two of its effectors, Myosin IIA and KIF20A participate in the coupling between actin and microtubule cytoskeleton. We have previously shown that RAB6-Myosin IIA interaction is critical for the fission of RAB6-positive transport carriers from Golgi/TGN membranes. Here we show that KIF20A is also involved in the fission process and serves to anchor RAB6 on Golgi/TGN membranes near microtubule nucleating sites. We provide evidence that the fission events occur at a limited number of hotspots sites. Our results suggest that coupling between actin and microtubule cytoskeletons driven by Myosin II and KIF20A ensures the spatial coordination between RAB6-positive vesicles fission from Golgi/TGN membranes and their exit along microtubules.
肌动蛋白和微管细胞骨架在高尔基体结构和功能中发挥重要作用，但它们之间的连接方式仍知之甚少。在这项研究中，我们研究了 RAB6 GTPase（一种与高尔基体相关的 RAB，参与高尔基体水平上的几个运输步骤的调节）及其两个效应物肌球蛋白 IIA 和 KIF20A 是否参与了肌动蛋白和微管细胞骨架之间的连接。我们之前已经表明，RAB6-肌球蛋白 IIA 相互作用对于 RAB6 阳性运输载体从高尔基体/TGN 膜的裂变至关重要。在这里，我们表明 KIF20A 也参与了裂变过程，并有助于将 RAB6 锚定在靠近微管成核位点的高尔基体/TGN 膜上。我们提供的证据表明，裂变事件发生在有限数量的热点部位。我们的研究结果表明，由肌球蛋白 II 和 KIF20A 驱动的肌动蛋白和微管细胞骨架之间的偶联确保了 RAB6 阳性囊泡从高尔基体/TGN 膜上的裂变与其沿着微管的排出之间的空间协调。
