Microtubule rescue at midzone edges promotes overlap stability and prevents spindle collapse during anaphase B
- Institut Curie, France
- Cambridge University, United Kingdom
Abstract
During anaphase B, molecular motors slide interpolar microtubules to elongate the mitotic spindle, contributing to the separation of chromosomes. However, sliding of antiparallel microtubules reduces their overlap, which may lead to spindle breakage, unless microtubules grow to compensate sliding. How sliding and growth are coordinated is still poorly understood. In this study, we have used the fission yeast S. pombe to measure microtubule dynamics during anaphase B. We report that the coordination of microtubule growth and sliding relies on promoting rescues at the midzone edges. This makes microtubules stable from pole to midzone, while their distal parts including the plus ends alternate between assembly and disassembly. Consequently, the midzone keeps a constant length throughout anaphase, enabling sustained sliding without the need for a precise regulation of microtubule growth speed. Additionally, we found that in S. pombe, which undergoes closed mitosis, microtubule growth speed decreases when the nuclear membrane wraps around the spindle midzone.
Data availability
Source code to reproduce and analyse the simulations is deposited in github at https://github.com/manulera/simulationsLeraRamirez2021Source code to annotate and analyse kymographs is deposited in github athttps://github.com/manulera/KymoAnalyzerSource code to find spindles in microscopy images is deposited in github at https://github.com/manulera/ImageAnalysisFunctions/tree/master/detection_functions/spindleWe have uploaded the source data for all figures as comma separated values files.
Article and author information
Author details
Manuel Lera-Ramirez
Funding
H2020 Marie Skłodowska-Curie Actions (675737)
- Manuel Lera-Ramirez
Gatsby Charitable Foundation
- François J Nédélec
Institut National Du Cancer
- Phong T Tran
Fondation ARC pour la Recherche sur le Cancer
- Phong T Tran
Ligue Contre le Cancer
- Phong T Tran
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Lera-Ramirez et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Microtubule rescue at midzone edges promotes overlap stability and prevents spindle collapse during anaphase B
eLife 11:e72630.
https://doi.org/10.7554/eLife.72630
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