Deterministic and stochastic approaches to a minimal model for the transition from autophagy to apoptosis

Bojie Yang1, Zhuoqin Yang1

  • 1School of Mathematical Sciences, Beihang University, Beijing 100191, China.

Insights

This study models the switch between autophagy and apoptosis, revealing how cellular noise influences these critical processes. Stronger noise increases randomness in the transition, offering new insights into cell fate regulation.

Area of Science:

  • Cellular biology
  • Systems biology
  • Biophysics

Background:

  • Autophagy and apoptosis are key cellular processes with interconnected regulatory mechanisms.
  • The precise molecular interplay and transitions between autophagy and apoptosis remain incompletely understood.
  • Autophagy's cytoprotective role involves inhibiting apoptosis, while apoptosis can suppress autophagy.

Purpose of the Study:

  • To develop a minimal model for exploring the transition dynamics between autophagy and apoptosis.
  • To integrate deterministic and stochastic cellular dynamics for a comprehensive analysis.
  • To investigate the role of noise in regulating the autophagy-apoptosis switch.

Main Methods:

  • Developed a minimal mathematical model integrating deterministic and stochastic cellular dynamics.
  • Analyzed system bistability and statistical properties under varying stress levels and noise strengths.
  • Investigated the impact of noise on feedback loops and cell fate transitions.

Main Results:

  • The cellular system demonstrated bistability, indicating distinct states of autophagy and apoptosis.
  • Noise was found to significantly affect the double negative feedback loops between autophagy and apoptosis.
  • Increased noise strength led to more random transitions between cellular states, particularly under continuous stress variations.

Conclusions:

  • The study provides a novel computational framework for understanding autophagy-apoptosis crosstalk.
  • Noise plays a critical role in modulating cell fate decisions and transition dynamics.
  • Findings offer potential avenues for future experimental validation and therapeutic targeting.

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