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Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations
Published on: September 20, 2019
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The Aurora B gradient sustains kinetochore stability in anaphase
Diana Papini1, Mark D Levasseur1, Jonathan M G Higgins1
1Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
Cell Reports
|November 10, 2021
Summary
Aurora B kinase activity, though reduced at centromeres during anaphase, maintains kinetochore stability and regulates disassembly through a central spindle gradient, ensuring accurate cell division.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Kinetochores are essential protein complexes that assemble on chromosomes during mitosis.
- Microtubule attachment to kinetochores ensures accurate chromosome segregation.
- Cyclin B-Cdk1 and Aurora B kinases are critical for kinetochore formation and stability.
Purpose of the Study:
- To investigate the role of Aurora B kinase activity during anaphase onset.
- To understand how kinetochore function is maintained when kinase activity declines.
- To elucidate the mechanism of Aurora B co-operation with Cyclin B-Cdk1 in anaphase.
Main Methods:
- Analysis of Aurora B kinase localization and activity gradients during mitosis.
- Phosphorylation site analysis of kinetochore substrates like Dsn1.
- Modeling of kinase-substrate interactions at the kinetochore and central spindle.
Main Results:
- Aurora B kinase leaves centromeres at anaphase but maintains activity in a central spindle gradient.
- This gradient phosphorylates kinetochore substrates, including Dsn1, modulating stability.
- Aurora B activity influences kinetochore disassembly as cells enter telophase.
Conclusions:
- Aurora B kinase plays a crucial role in maintaining kinetochore function during anaphase.
- A central spindle gradient of Aurora B activity is sufficient to regulate kinetochore stability and disassembly.
- Aurora B co-operates with Cyclin B-Cdk1 to ensure proper kinetochore function throughout anaphase.
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