Kinesin-6 Klp9 orchestrates spindle elongation by regulating microtubule sliding and growth
Abstract
Mitotic spindle function depends on the precise regulation of microtubule dynamics and microtubule sliding. Throughout mitosis, both processes have to be orchestrated to establish and maintain spindle stability. We show that during anaphase B spindle elongation in S. pombe, the sliding motor Klp9 (kinesin-6) also promotes microtubule growth in vivo. In vitro, Klp9 can enhance and dampen microtubule growth, depending on the tubulin concentration. This indicates that the motor is able to promote and block tubulin subunit incorporation into the microtubule lattice in order to set a well-defined microtubule growth velocity. Moreover, Klp9 recruitment to spindle microtubules is dependent on its dephosphorylation mediated by XMAP215/Dis1, a microtubule polymerase, creating a link between the regulation of spindle length and spindle elongation velocity. Collectively, we unravel the mechanism of anaphase B, from Klp9 recruitment to the motors dual-function in regulating microtubule sliding and microtubule growth, allowing an inherent coordination of both processes.
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A source data file for all data sets used in Figure 1- 7 has been provided.
Article and author information
Author details
Funding
French Ministry of Science and Education
- Lara Katharina Krüger
Fondation ARC pour la Recherche sur le Cancer
- Lara Katharina Krüger
La Ligue Contre le Cancer
- Phong T Tran
Fondation ARC pour la Recherche sur le Cancer
- Phong T Tran
INCa
- Phong T Tran
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Thomas Surrey, Centre for Genomic Regulation (CRG), Spain
Version history
- Received: February 12, 2021
- Accepted: June 2, 2021
- Accepted Manuscript published: June 3, 2021 (version 1)
- Version of Record published: June 15, 2021 (version 2)
Copyright
© 2021, Krüger 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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