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Updated: Aug 3, 2026
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Mouse models of cell cycle regulators: new paradigms
1National Cancer Institute, Mouse Cancer Genetics Program, NCI-Frederick, MD 21702-1201, USA.
Results and Problems in Cell Differentiation
|August 15, 2006
Summary
Mouse models reveal surprising in vivo functions of cell cycle regulators, challenging the textbook model and highlighting redundancy in cell cycle control. These findings have implications for understanding development and cancer.
Area of Science:
- Cell Biology
- Developmental Biology
- Cancer Biology
Background:
- The textbook model of mammalian cell cycle regulation, based on cell line studies, posits distinct functions for cyclin/cyclin-dependent kinase (Cdk) complexes.
- Evolution of multicellularity introduced complex layers of cell cycle control involving numerous Cdks, cyclins, and inhibitors.
Purpose of the Study:
- To review the textbook model of cell cycle regulation.
- To provide an overview of findings from genetically engineered mouse models targeting cell cycle regulators.
- To discuss the in vivo functions and developmental roles of these regulators.
Main Methods:
- Analysis of phenotypes from various genetically engineered mouse models with targeted cell cycle regulators.
- Examination of double-gene ablation models to uncover genetic and functional interactions.
- Review of existing literature on cell cycle regulation.
Main Results:
- Mouse models revealed unexpected in vivo functions of cell cycle proteins, impacting development (embryonic lethality, organ defects) and tumor formation.
- Studies identified functional complementation and genetic interactions between cell cycle regulators (e.g., cyclin D1 and p27, Cdk2 and Cdc2).
- New roles for regulators were discovered, including Cdc2 in S phase regulation and p27 in cell migration.
Conclusions:
- In vivo studies using mouse models have significantly expanded our understanding of cell cycle regulation beyond the textbook model.
- Findings suggest a high degree of redundancy among cell cycle regulators, necessitating a revised model.
- These insights have critical implications for human cancer research and therapeutic strategies.
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