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Spatiotemporal Analysis of Cytokinetic Events in Fission Yeast
Published on: February 20, 2017
Eavesdropping on the cytoskeleton: progress and controversy in the yeast morphogenesis checkpoint
Mignon A Keaton1, Daniel J Lew
1Department of Pharmacology and Cancer Biology, Box 3813, Duke University Medical Center, Durham, NC 27710, USA.
Current Opinion in Microbiology
|October 24, 2006
Summary
Yeast morphogenesis checkpoint arrests cell division when the cytoskeleton is damaged. This process involves Swe1p kinase, which regulates mitosis entry by inhibiting cyclin-dependent kinase (CDK).
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The morphogenesis checkpoint links bud formation to mitosis in yeast.
- Cytoskeletal damage (actin or septin) triggers cell cycle arrest via Swe1p.
- Swe1p phosphorylates and inhibits the mitosis-promoting cyclin-dependent kinase (CDK).
Purpose of the Study:
- To investigate the regulatory mechanisms of Swe1p in response to cytoskeletal perturbations.
- To understand the role of Swe1p phosphorylation sites in controlling its activity and degradation.
- To explore the link between Swe1p regulation and DNA-responsive checkpoints.
Main Methods:
- Analysis of Swe1p phosphorylation sites using biochemical and genetic approaches.
- Investigating the impact of actin and septin cytoskeleton organization on Swe1p regulators.
- Comparative analysis of Swe1p regulation across different species.
Main Results:
- Identified 61 phosphorylation sites on Swe1p targeted by CDKs and Polo-related kinases.
- Demonstrated that while phosphorylation sites are not conserved, Swe1p degradation control is conserved.
- Highlighted conserved links between Swe1p regulation and DNA-responsive checkpoints in vertebrates.
- Revealed ongoing controversy regarding Swe1p response to actin perturbations post-budding.
Conclusions:
- Swe1p is a key regulator of the morphogenesis checkpoint, integrating cytoskeletal status with cell cycle progression.
- The regulation of Swe1p activity and degradation involves complex phosphorylation events.
- Conserved mechanisms link cytoskeletal checkpoints to DNA damage responses, suggesting fundamental roles in cell cycle control.
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