The Ndc80 complex bridges two Dam1 complex rings
- University of Washington, United States
- Dana-Farber Cancer Institute, United States
Abstract
Strong kinetochore-microtubule attachments are essential for faithful segregation of sister chromatids during mitosis. The Dam1 and Ndc80 complexes are the main microtubule binding components of the Saccharomyces cerevisiae kinetochore. Cooperation between these two complexes enhances kinetochore-microtubule coupling and is regulated by Aurora B kinase. We show that the Ndc80 complex can simultaneously bind and bridge across two Dam1 complex rings through a tripartite interaction, each component of which is regulated by Aurora B kinase. Mutations in any one of the Ndc80p interaction regions abrogates the Ndc80 complex's ability to bind two Dam1 rings in vitro, and results in kinetochore biorientation and microtubule attachment defects in vivo. We also show that an extra-long Ndc80 complex, engineered to space the two Dam1 rings further apart, does not support growth. Taken together, our work suggests that each kinetochore in vivo contains two Dam1 rings and that proper spacing between the rings is vital.
Article and author information
Author details
Funding
National Institutes of Health (R01 GM040506)
- Trisha N Davis
National Institutes of Health (P41 GM103533)
- Michael J MacCoss
National Institutes of Health (R01 GM079373)
- Charles L Asbury
National Institutes of Health (S10 RR026406)
- Charles L Asbury
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Kim 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 Ndc80 complex bridges two Dam1 complex rings
eLife 6:e21069.
https://doi.org/10.7554/eLife.21069
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