Kinesin-induced buckling reveals the limits of microtubule self-repair

Nandakumar, S.; Bosche, J.; Wieczorek, M.; Albrecht, C. M.; König, B.; Grünewald, M.; Santen, L.; Diez, S.; Shaebani, R.; Schaedel, L.

doi:10.1101/2025.09.08.672697

bioRxiv · 10.1101/2025.09.08.672697

Kinesin-induced buckling reveals the limits of microtubule self-repair

Nandakumar, S.·Bosche, J.·Wieczorek, M.·Albrecht, C. M.·König, B.·Grünewald, M.·Santen, L.·Diez, S.·Shaebani, R.·Schaedel, L.

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Abstract

Microtubules are stiff cytoskeletal polymers whose ability to rapidly switch between growth and disassembly relies on a metastable lattice. This metastability is also reflected in their sensitivity to environmental conditions and in intrinsic lattice dynamics, where spontaneous tubulin loss is balanced by tubulin incorporation from solution - a process that also enables microtubules to self-repair when damaged. Whether such intrinsic self-repair is sufficient to preserve microtubule integrity during dynamic molecular-motor induced buckling, which frequently occurs in cells, remains unclear. Here, we show that kinesin-driven microtubule buckling in vitro induces severe lattice damage, leading to extensive tubulin incorporation. In many cases, however, the damage exceeds the microtubules capacity for self-repair, resulting in breakage. In contrast, microtubules survive continuous buckling substantially longer in the presence of intracellular factors. Our results identify the limits of intrinsic microtubule self-repair and demonstrate that additional cellular mechanisms are essential to maintain microtubule integrity under sustained mechanical load.

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Nandakumar, S., Bosche, J., Wieczorek, M., Albrecht, C. M., König, B., Grünewald, M., Santen, L., Diez, S., Shaebani, R., Schaedel, L.. 2025-09-12. Kinesin-induced buckling reveals the limits of microtubule self-repair. https://doi.org/10.1101/2025.09.08.672697

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