A Hill type equation can predict target gene expression driven by p53 pulsing.

Area of Science:

• Molecular Biology
• Systems Biology
• Biophysics

Background:

• Target gene expression is modulated by transcription factor dynamics.
• p53 pulsing is a key regulatory mechanism in cellular responses.
• Understanding factors influencing p53 target gene expression is crucial.

Purpose of the Study:

• To elucidate the mechanism of target gene expression dynamics under p53 pulsing.
• To investigate the impact of p53 pulse duration, frequency, binding affinity, and transcription rate.
• To develop a predictive model for target gene expression.

Main Methods:

• Analytical solution of a simple mathematical model for p53 dynamics.
• Investigation of varying pulse parameters (duration, frequency, affinity, rate).
• Development and validation of a Hill-type equation for gene expression.

Main Results:

• Target gene expression fold change increases with the number of p53 pulses.
• An optimal frequency of 0.18 h⁻¹ for two p53 pulses maximizes fold change.
• p53 pulsing can achieve higher gene expression than sustained p53 levels.
• A derived Hill-type equation accurately characterizes target gene expression with 23% average error.

Conclusions:

• p53 pulse duration and frequency are critical for fine-tuning target gene expression.
• The developed equation provides a framework for understanding transcription factor dynamics.
• Higher binding affinity contributes to enhanced target gene expression regulation.