Kinesin-1 is a nanoscale molecular motor that walks towards the fast-growing (plus) ends of microtubules, hauling molecular cargo to specific reaction sites in cells. Kinesin-driven transport is central to the self-organization of eukaryotic cells and shows great promise as a tool for nano-engineering¹. Recent work hints that kinesin may also play a role in modulating the stability of its microtubule track, both in vitro^2,3 and in vivo⁴, but the results are conflicting^5,6,7 and the mechanisms are unclear. Here, we report a new dimension to the kinesin–microtubule interaction, whereby strong-binding state (adenosine triphosphate (ATP)-bound and apo) kinesin-1 motor domains inhibit the shrinkage of guanosine diphosphate (GDP) microtubules by up to two orders of magnitude and expand their lattice spacing by ~1.6%. Our data reveal an unexpected mechanism by which the mechanochemical cycles of kinesin and tubulin interlock, and so allow motile kinesins to influence the structure, stability and mechanics of their microtubule track.

Kinesin-1是一种纳米级分子马达，可向微管快速增长的末端移动，将分子货物运送至细胞中的特定反应位点。驱动蛋白驱动的运输是真核细胞自组织的核心，并显示出作为纳米工程工具的巨大前景¹。最近的工作提示，驱动蛋白在体外^2,3和体内⁴都可能在调节其微管轨迹的稳定性中发挥作用，但结果相互矛盾^5,6,7而且机制尚不清楚。在这里，我们报告了驱动蛋白与微管相互作用的新维度，即强结合状态（三磷酸腺苷（ATP）结合和载脂蛋白）的驱动蛋白1运动域抑制了鸟苷二磷酸（GDP）微管的收缩多达两个数量级并扩大其晶格间距约1.6％。我们的数据揭示了驱动蛋白和微管蛋白的机械化学循环互锁的意外机制，因此使运动型驱动蛋白能够影响其微管轨迹的结构，稳定性和力学。