The structure of the Ctf19c/CCAN from budding yeast
Abstract
Eukaryotic kinetochores connect spindle microtubules to chromosomal centromeres. A group of proteins called the Ctf19 complex (Ctf19c) in yeast and the constitutive centromere associated network (CCAN) in other organisms creates the foundation of a kinetochore. The Ctf19c/CCAN influences the timing of kinetochore assembly, sets its location by associating with a specialized nucleosome containing the histone H3 variant Cse4/CENP-A, and determines the organization of the microtubule attachment apparatus. We present here the structure of a reconstituted 13-subunit Ctf19c determined by cryo-electron microscopy at ~4 Å resolution. The structure accounts for known and inferred contacts with the Cse4 nucleosome and for an observed assembly hierarchy. We describe its implications for establishment of kinetochores and for their regulation by kinases throughout the cell cycle.
Data availability
We have deposited the model coordinates and cryo-EM maps in the PDB (6NUW) and EMDB (EMD-0523). Tracking files for imaging experiments are included as a source data file associated with Figure 3.
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Model coordinates from The structure of the Ctf19c/CCAN from budding yeastProtein Data Bank, 6NUW.
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Cryo-EM from The structure of the Ctf19c/CCAN from budding yeastElectron Microscopy Data Bank, EMD-0523.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Stephen M Hinshaw
- Stephen C Harrison
Helen Hay Whitney Foundation
- Stephen M Hinshaw
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Andrea Musacchio, Max Planck Institute of Molecular Physiology, Germany
Version history
- Received: December 8, 2018
- Accepted: February 13, 2019
- Accepted Manuscript published: February 14, 2019 (version 1)
- Version of Record published: March 8, 2019 (version 2)
- Version of Record updated: March 5, 2020 (version 3)
Copyright
© 2019, Hinshaw & Harrison
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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Further reading
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- Structural Biology and Molecular Biophysics
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