A Force-Induced Directional Switch of a Molecular Motor Enables Parallel Microtubule Bundle Formation
A Force-Induced Directional Switch of a Molecular Motor Enables Parallel Microtubule Bundle Formation
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DOI：
10.1016/j.cell.2016.09.029
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发表时间：
2016-10-06
期刊：
影响因子：
64.5
通讯作者：
Vaziri, Alipasha
中科院分区：
文献类型：
--
作者：
Molodtsov, Maxim I.;Mieck, Christine;Vaziri, Alipasha
微管组织中心（Microtubule-organizing centers，MTOC）是微管的核心，可以在任何方向自主生长。为了从单个MTOC产生平行微管束，需要协调多个微管的生长，但其潜在机制尚不清楚。在这里，我们表明，一个保守的双组分系统组成的正端跟踪EB 1和负端定向分子马达驱动蛋白-14是足以促进平行微管生长。潜在的机制依赖于驱动蛋白-14引导正末端沿着现有微管生长的能力。这一发现的普遍性得到了酵母、果蝇和人类EB 1/驱动蛋白-14对的支持。我们证明，加端指导涉及电机的方向开关，由于通过不断增长的微管端施加的力。所描述的机制可以解释平行微管网络的产生所需的广泛的细胞功能，如纺锤体组装或细胞极化。
Microtubule-organizing centers (MTOCs) nucleate microtubules that can grow autonomously in any direction. To generate bundles of parallel microtubules originating from a single MTOC, the growth of multiple microtubules needs to coordinated, but the underlying mechanism is unknown. Here, we show that a conserved two-component system consisting of the plus-end tracker EB1 and the minus-end-directed molecular motor Kinesin-14 is sufficient to promote parallel microtubule growth. The underlying mechanism relies on the ability of Kinesin-14 to guide growing plus ends along existing microtubules. The generality of this finding is supported by yeast, Drosophila, and human EB1/Kinesin-14 pairs. We demonstrate that plus-end guiding involves a directional switch of the motor due to a force applied via a growing microtubule end. The described mechanism can account for the generation of parallel microtubule networks required for a broad range of cellular functions such as spindle assembly or cell polarization.