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Updated: May 22, 2026
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
A systematic screen reveals new elements acting at the G2/M cell cycle control.
Francisco J Navarro1, Paul Nurse
1Cell Cycle Lab, Cancer Research UK-London Research Institute, Lincoln's Inn Fields 44, London WC2A 3LY, UK. Francisco.Navarro@cancer.org.uk
Genome Biology
|May 26, 2012
Summary
Researchers screened fission yeast genes and found 18 new regulators of cell division. These findings uncover novel molecular mechanisms controlling the G2 to mitosis transition, impacting cyclin-dependent kinase (CDK) regulation.
Area of Science:
- Cell Biology
- Genetics
- Molecular Biology
Background:
- Cell cycle progression is tightly regulated by cyclin-dependent kinases (CDKs) in eukaryotes.
- In fission yeast (Schizosaccharomyces pombe), G2/M CDK activation involves dephosphorylation of Tyr15, influenced by stress and cell geometry.
- Understanding G2/M control is crucial for comprehending cell division.
Purpose of the Study:
- To systematically identify genes that, when deleted, cause premature entry into mitosis.
- To gain a comprehensive understanding of the regulatory network governing the G2 to M phase transition.
Main Methods:
- Conducted a large-scale screen of approximately 3,000 fission yeast gene deletion mutants.
- Focused on identifying genes that negatively regulate mitotic entry.
Main Results:
- Identified 18 genes that negatively regulate mitotic entry; 7 were previously undescribed cell cycle regulators.
- Eleven genes function via stress response and cell geometry pathways affecting CDK Tyr15 phosphorylation.
- Four genes regulate G2/M transition through unknown pathways, and three act independently of CDK Tyr15 phosphorylation.
Conclusions:
- Discovered novel components within known pathways regulating CDK Tyr15 phosphorylation.
- Identified new molecular mechanisms controlling mitotic entry, expanding our knowledge of cell cycle regulation.
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