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Updated: Dec 28, 2025
14:57
Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
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Dynamic Behavior of p53 Driven by Delay and a Microrna-34a-Mediated Feedback Loop
Chunyan Gao1, Haihong Liu1, Fang Yan1,2
1Department of Mathematics, Yunnan Normal University, Kunming 650092, China.
International Journal of Molecular Sciences
|February 20, 2020
Summary
The p53-Mdm2 signaling pathway exhibits oscillations due to time delays and microRNA-34a, suggesting novel anti-cancer drug targets. These findings highlight the tumor-suppressing roles of time delay and miR-34a in promoting p53 oscillations.
Area of Science:
- Systems Biology
- Molecular Oncology
- Biophysics
Background:
- The tumor suppressor protein p53 is a key regulator of cellular responses to DNA damage.
- Understanding the dynamics of the p53 signaling pathway is crucial for cancer research.
Purpose of the Study:
- To develop an integrated model of the p53 signaling pathway in response to DNA damage.
- To analyze the stability and oscillatory dynamics of the p53-Mdm2 module.
- To investigate the roles of time delay and microRNA-34a (miR-34a) in p53 regulation.
Main Methods:
- Theoretical analysis of a mathematical model.
- Numerical simulations to explore system dynamics.
- Bifurcation analysis to identify critical parameter values.
Main Results:
- Time delay acts as a bifurcation parameter, inducing supercritical Hopf bifurcations and oscillations in the p53-Mdm2 module.
- A positive feedback loop involving p53* and miR-34a generates limit-cycle oscillations.
- miR-34a influences the critical value of Hopf bifurcation in delay-induced p53 networks.
- ATM activation by DNA damage leads to two Hopf bifurcations in p53* dynamics.
Conclusions:
- Both time delay and miR-34a exhibit tumor-suppressing functions by promoting p53 oscillation or high-level expression.
- Targeting miR-34a and time delay presents a potential strategy for developing anti-cancer drugs.
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