Microtubule instability stems from the low energy of tubulin dimer interactions, which sets the growing polymer close to its disassembly conditions. Molecular motors use ATP hydrolysis to produce mechanical work and move on microtubules. This raises the possibility that the mechanical work produced by walking motors can break dimer interactions and trigger microtubule disassembly. We tested this hypothesis by studying the interplay between microtubules and moving molecular motors in vitro. Our results show that molecular motors can remove tubulin dimers from the lattice and rapidly destroy microtubules. We also found that dimer removal by motors was compensated for by the insertion of free tubulin dimers into the microtubule lattice. This self-repair mechanism allows microtubules to survive the damage induced by molecular motors as they move along their tracks. Our study reveals the existence of coupling between the motion of molecular motors and the renewal of the microtubule lattice.

微管不稳定性源于微管蛋白二聚体相互作用的低能量，这使得正在生长的聚合物接近其分解条件。分子马达利用 ATP 水解产生机械功并在微管上移动。这增加了行走马达产生的机械功可以破坏二聚体相互作用并触发微管分解的可能性。我们通过研究体外微管和移动分子马达之间的相互作用来验证这一假设。我们的研究结果表明，分子马达可以从晶格中去除微管蛋白二聚体并迅速破坏微管。我们还发现，通过将游离微管蛋白二聚体插入微管晶格来补偿电机对二聚体的去除。这种自我修复机制使微管能够在分子马达沿其轨道移动时免受损伤。我们的研究揭示了分子马达运动与微管晶格更新之间存在耦合。