Multimodal microtubule binding by the Ndc80 kinetochore complex.
Gregory M Alushin1, Vivek Musinipally, Daniel Matson
1Biophysics Graduate Group, University of California Berkeley, Berkeley, California, USA.
Nature Structural & Molecular Biology
|October 23, 2012
Summary
The Ndc80 complex attaches to microtubules during cell division. Phosphorylation of its tail by Aurora B kinase regulates microtubule binding, controlling cell division dynamics.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The Ndc80 complex is crucial for kinetochore-microtubule attachment, a vital process in cell division.
- This complex has a globular head and an unstructured tail containing phosphorylation sites regulated by Aurora B kinase.
Purpose of the Study:
- To investigate the role of the Ndc80 complex's tail in microtubule binding and cooperative interactions.
- To understand how Aurora B kinase phosphorylation affects Ndc80 complex function.
Main Methods:
- Biochemical analyses
- Cell biological studies
- Electron microscopy
Main Results:
- Two tail segments with phosphorylation sites become ordered at specific interfaces.
- These ordered segments interact with tubulin and adjacent Ndc80 heads on microtubules.
- Phosphorylation disrupts these interactions, affecting Ndc80 complex binding.
Conclusions:
- The phosphorylation state of the Ndc80 complex tail tunes its interaction with growing or shrinking microtubule ends.
- This provides a regulatory mechanism for kinetochore-microtubule attachment during cell division.
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