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Adaptive changes in the kinetochore architecture facilitate proper spindle assembly
Valentin Magidson1, Raja Paul2,3, Nachen Yang1
1Wadsworth Center, New York State Department of Health, Albany, New York 12201, USA.
Nature Cell Biology
|August 11, 2015
Summary
Kinetochore size dynamically changes during cell division, starting large and compacting after microtubule attachment. This dynamic architecture optimizes both speed and accuracy of mitotic spindle formation.
Area of Science:
- Cell Biology
- Biophysics
Background:
- Mitotic spindle assembly depends on microtubule capture by kinetochores.
- Kinetochore size influences spindle assembly efficiency and fidelity.
Purpose of the Study:
- To investigate the dynamic changes in kinetochore architecture during mitosis.
- To understand the relationship between kinetochore shape, microtubule attachment, and spindle assembly.
Main Methods:
- Live-cell microscopy of cultured human cells.
- Computational modeling of kinetochore-microtubule interactions.
Main Results:
- Kinetochores initially form large crescents that compact after end-on microtubule attachments.
- Centromere rotation precedes end-on attachment and kinetochore compaction.
- Computational models accurately predict spindle assembly times and error rates.
Conclusions:
- Kinetochore expansion and compaction are crucial for robust spindle assembly.
- Dynamic kinetochore architecture optimizes both speed and accuracy, challenging previous assumptions about size-fidelity trade-offs.
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