The COMA complex interacts with Cse4 and positions Sli15/Ipl1 at the budding yeast inner kinetochore
- Ludwig-Maximilians-Universität München, Germany
- Vienna Biocenter, Germany
- Medical University of Vienna, Austria
- Max Planck Institute of Biochemistry, Germany
- University Paris-Sud, France
Abstract
Kinetochores are macromolecular protein complexes at centromeres that ensure accurate chromosome segregation by attaching chromosomes to spindle microtubules and integrating safeguard mechanisms. The inner kinetochore is assembled on CENP-A nucleosomes and has been implicated in establishing a kinetochore-associated pool of Aurora B kinase, a chromosomal passenger complex (CPC) subunit, which is essential for chromosome biorientation. By performing crosslink-guided in vitro reconstitution of budding yeast kinetochore complexes we showed that the Ame1/Okp1CENP-U/Q heterodimer, which forms the COMA complex with Ctf19/Mcm21CENP-P/O, selectively bound Cse4CENP-A nucleosomes through the Cse4 N-terminus. The Sli15/Ipl1INCENP/Aurora-B core-CPC interacted with COMA in vitro through the Ctf19 C-terminus whose deletion affects accurate chromosome segregation in a Sli15 wild-type background. Tethering Sli15 to Ame1/Okp1 rescued synthetic lethality upon Ctf19 depletion in a Sli15 centromere-targeting deficient mutant. This study shows molecular characteristics of the point-centromere inner kinetochore architecture and suggests a role for the Ctf19 C-terminus in mediating accurate chromosome segregation.
Data availability
The mass spectrometry raw data was uploaded to the PRIDE Archive and is publicly available through the following identifiers: PXD011235 (COMA-Sli15/Ipl1); PXD011236 (CCAN)
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AOCM-CPCPride Archive, PXD011235 (COMA-Sli15/Ipl1).
Article and author information
Author details
Funding
European Research Council (ERC-StG MolStruKT no 638218)
- Franz Herzog
Human Frontier Science Program (RGP0008/2015)
- Franz Herzog
Deutsche Forschungsgemeinschaft
- Mia Potocnjak
- Götz Hagemann
- Victor Solis-Mezarino
- Franz Herzog
Bavarian Research Center for Molecular Biosystems
- Franz Herzog
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Fischböck-Halwachs 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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The COMA complex interacts with Cse4 and positions Sli15/Ipl1 at the budding yeast inner kinetochore
eLife 8:e42879.
https://doi.org/10.7554/eLife.42879
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