Molecular basis of outer kinetochore assembly on CENP-T
- Max Planck Institute of Molecular Physiology, Germany
- Chemical Genomics Centre of the Max Planck Society, Germany
- Vienna Biocenter, Austria
- Vienna Biocenter, Germany
Abstract
Stable kinetochore-microtubule attachment is essential for cell division. It requires recruitment of outer kinetochore microtubule binders by centromere proteins C and T (CENP-C and CENP-T). To study the molecular requirements of kinetochore formation, we reconstituted the binding of the MIS12 and NDC80 outer kinetochore subcomplexes to CENP-C and CENP-T. Whereas CENP-C recruits a single MIS12:NDC80 complex, we show here that CENP-T binds one MIS12:NDC80 and two NDC80 complexes upon phosphorylation by the mitotic CDK1:Cyclin B complex at three distinct CENP-T sites. Visualization of reconstituted complexes by electron microscopy supports this model. Binding of CENP-C and CENP-T to MIS12 is competitive, and therefore CENP-C and CENP-T act in parallel to recruit two MIS12 and up to four NDC80 complexes. Our observations provide a molecular explanation for the stoichiometry of kinetochore components and its cell cycle regulation, and highlight how outer kinetochore modules bridge distances of well over 100 nm.
Article and author information
Author details
Pim J Huis in 't Veld
Funding
European Research Council (AdG 669686 RECEPIANCE)
- Andrea Musacchio
Deutsche Forschungsgemeinschaft (CRC1093)
- Andrea Musacchio
European Molecular Biology Organization (ALTF 262-2009)
- Sadasivam Jeganathan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Huis in 't Veld 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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Molecular basis of outer kinetochore assembly on CENP-T
eLife 5:e21007.
https://doi.org/10.7554/eLife.21007
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