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Microtubules acquire resistance from mechanical breakage through intralumenal acetylation.

ABSTRACT: Eukaryotic cells rely on long-lived microtubules for intracellular transport and as compression-bearing elements. We considered that long-lived microtubules are acetylated inside their lumen and that microtubule acetylation may modify microtubule mechanics. Here, we found that tubulin acetylation is required for the mechanical stabilization of long-lived microtubules in cells. Depletion of the tubulin acetyltransferase TAT1 led to a significant increase in the frequency of microtubule breakage. Nocodazole-resistant microtubules lost upon removal of acetylation were largely restored by either pharmacological or physical removal of compressive forces. In in vitro reconstitution experiments, acetylation was sufficient to protect microtubules from mechanical breakage. Thus, acetylation increases mechanical resilience to ensure the persistence of long-lived microtubules.

SUBMITTER: Xu Z

PROVIDER: S-EPMC5457157 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Microtubules acquire resistance from mechanical breakage through intralumenal acetylation.

Xu Zhenjie Z Schaedel Laura L Portran Didier D Aguilar Andrea A Gaillard Jérémie J Marinkovich M Peter MP Théry Manuel M Nachury Maxence V MV

Science (New York, N.Y.) 20170401 6335

Eukaryotic cells rely on long-lived microtubules for intracellular transport and as compression-bearing elements. We considered that long-lived microtubules are acetylated inside their lumen and that microtubule acetylation may modify microtubule mechanics. Here, we found that tubulin acetylation is required for the mechanical stabilization of long-lived microtubules in cells. Depletion of the tubulin acetyltransferase TAT1 led to a significant increase in the frequency of microtubule breakage. ...[more]

PMID: 28428427

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