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Updated: Jul 31, 2026
11:23
Measuring Cell Cycle Progression Kinetics with Metabolic Labeling and Flow Cytometry
Published on: May 22, 2012
The Florey Lecture, 1990. How is the cell division cycle regulated?
1Department of Biochemistry, University of Oxford, U.K.
Summary
Mitosis onset in eukaryotic cells is linked to cell size and cell cycle completion. A regulatory network activates the p34cdc2 protein kinase, suggesting a universal control mechanism for mitosis across eukaryotes.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Mitosis, the process of cell division, is a fundamental aspect of eukaryotic cell proliferation.
- The regulation of mitosis ensures accurate chromosome segregation and is tightly controlled by specific molecular mechanisms.
- Previous research has identified cell size and completion of DNA replication (S-phase) as critical factors influencing cell cycle progression.
Purpose of the Study:
- To explore the regulatory network controlling the onset of mitosis in eukaryotic cells.
- To investigate the role of the p34cdc2 protein kinase in initiating mitosis.
- To determine if the controls regulating mitosis are conserved across different eukaryotic organisms.
Main Methods:
- The study discusses regulatory gene networks in fission yeast.
- It focuses on the activation of the p34cdc2 protein kinase through dephosphorylation.
- Comparative analysis of regulatory mechanisms in yeast and vertebrate cells is implied.
Main Results:
- Mitosis onset is coupled to achieving a critical cell mass and completing the preceding S-phase.
- In fission yeast, a regulatory gene network activates the p34cdc2 protein kinase.
- Activation of p34cdc2 involves dephosphorylation of a tyrosine residue within its ATP-binding site.
Conclusions:
- The p34cdc2 protein kinase plays a crucial role in regulating the initiation of mitosis.
- The findings suggest a conserved, universal control mechanism for mitosis in all eukaryotic cells.
- Cell size and S-phase completion are key checkpoints for initiating the cell division process.
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