Related Experiment Video
Updated: May 19, 2026
07:47
Directly Measuring Forces Within Reconstituted Active Microtubule Bundles
Published on: May 10, 2022
The Ndc80 kinetochore complex directly modulates microtubule dynamics.
Neil T Umbreit1, Daniel R Gestaut, Jerry F Tien
1Department of Biochemistry, Department of Physiology and Biophysics, Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA.
Summary
The Ndc80 complex directly stabilizes microtubules and promotes their growth. Aurora B kinase phosphorylation of Ndc80 impairs this function, revealing a new role for Aurora B in controlling microtubule dynamics.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The Ndc80 complex is crucial for kinetochore-microtubule attachment.
- Its role in influencing microtubule dynamics at kinetochores requires clarification.
Purpose of the Study:
- To investigate whether the Ndc80 complex directly modulates microtubule dynamics.
- To determine the impact of Aurora B kinase phosphorylation on Ndc80 complex function in microtubule dynamics.
Main Methods:
- In vitro reconstitution assays using the human Ndc80 complex.
- In vivo studies involving mutations mimicking or blocking Aurora B phosphorylation.
- Analysis of kinetochore-microtubule attachment and dynamics.
Main Results:
- The Ndc80 complex directly stabilizes disassembling microtubule tips and promotes rescue in vitro.
- Aurora B-mediated phosphorylation of the Ndc80 complex's N-terminal domain impairs microtubule rescue.
- Phosphorylation-defective Ndc80 mutants show altered kinetochore oscillations and attachment stability.
Conclusions:
- The Ndc80 complex directly regulates microtubule dynamics by stabilizing microtubule tips and promoting rescue.
- Aurora B kinase controls microtubule dynamics via phosphorylation of the Ndc80 complex, independent of attachment stability.
- This phosphorylation event is critical for proper kinetochore function and cell division.
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