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Oscillations in delayed positive feedback systems
Christopher J Ryzowicz1, Richard Bertram1,2,3, Bhargav R Karamched1,2,3
1Department of Mathematics, Florida State University, Tallahassee, FL 32306, USA.
Physical Chemistry Chemical Physics : PCCP
|September 18, 2024
Summary
Temporal delay in positive feedback loops can generate long-lasting biological oscillations. This finding applies to genetic toggle and one-way switches, challenging existing models of biological rhythm generation.
Area of Science:
- Systems biology
- Biophysics
- Molecular biology
Background:
- Positive feedback loops are crucial for biological circuit function.
- Temporal delays are often considered in negative feedback systems for oscillation generation.
Purpose of the Study:
- To investigate the impact of temporal delay on the dynamics of canonical positive feedback models.
- To explore the role of delayed positive feedback in generating biological oscillations.
Main Methods:
- Mathematical modeling of genetic toggle and one-way switches with delayed feedback.
- Analysis of transient oscillation duration based on delay magnitude and initial conditions.
- Application of models to biological systems like Cdc2-Cyclin B/Wee1 and genetic regulatory networks.
Main Results:
- Long-lasting transient oscillations were observed in both models under general conditions.
- Oscillation duration is significantly influenced by the magnitude of temporal delay and initial conditions.
- Demonstrated the existence of long-lasting oscillations in specific biological examples.
Conclusions:
- Delayed positive feedback systems can generate oscillations, challenging the canonical view of negative feedback systems.
- Temporal delays in positive feedback loops are a viable mechanism for generating biological oscillations.
- Findings have implications for understanding biological rhythms and designing synthetic biological circuits.
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