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Updated: May 30, 2026
12:26
Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
Published on: May 3, 2018
Three Observations That Have Changed Our Understanding of Cyclin D1 and p27 in Cell Cycle Control
1Department of Molecular Medicine, Case Western Reserve University, and Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.
Genes & Cancer
|July 23, 2011
Summary
Cell cycle control involves cyclin D1 oscillations and p27 regulation. Checkpoint kinases suppress cyclin D1, influencing cell proliferation rates and neural cell protection.
Area of Science:
- Cell Biology
- Molecular Biology
Background:
- Traditional cell cycle studies often focus on synchronized cultures and early phases.
- Cyclin D1 and p27(Kip1) (p27) are known regulators responding to cellular environment and controlling cell cycle entry.
Purpose of the Study:
- To investigate the roles of cyclin D1 and p27 in all cell cycle phases, including withdrawal.
- To present a new model of cell cycle control based on dynamic interactions.
Main Methods:
- Microinjection
- Quantitative image analysis
- Time-lapse microscopy
Main Results:
- Cyclin D1 levels oscillate throughout the normal cell cycle.
- Checkpoint kinases suppress cyclin D1 during S phase.
- p27 levels are dynamically regulated by cyclin D1, determining proliferation rate.
Conclusions:
- A novel model of cell cycle control is proposed, involving ras activity, cyclin D1, and p27.
- The model predicts and is validated by the role of checkpoint kinases in cyclin D1 regulation and neural cell protection.
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