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Updated: May 14, 2026
10:38
Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters
Published on: September 27, 2012
Deterministic versus stochastic models for circadian rhythms
D Gonze1, J Halloy, A Goldbeter
1Unité de Chronobiologie Théorique, Faculté des Sciences, Université Libre de Bruxelles, Campus Plaine, C.P. 231, B-1050 Brussels, Belgium.
Journal of Biological Physics
|January 25, 2013
Summary
Molecular noise impacts circadian rhythms, but robust oscillations persist even with low molecule counts. Stochastic models closely align with deterministic predictions for these biological clocks.
Area of Science:
- * Biochemistry and Molecular Biology
- * Systems Biology
- * Chronobiology
Background:
- * Circadian rhythms, essential biological processes with ~24-hour cycles, are driven by gene expression's negative autoregulation.
- * Deterministic models explain circadian rhythms under constant conditions, entrainment by light, and phase shifts.
- * Molecular noise becomes significant at low molecule counts, necessitating stochastic simulations.
Purpose of the Study:
- * To investigate the impact of molecular noise on circadian rhythms using stochastic models.
- * To compare stochastic model predictions with a deterministic core model for circadian oscillations.
Main Methods:
- * Two stochastic versions of a core circadian rhythm model (PER protein in Drosophila, FRQ protein in Neurospora) were developed.
- * A non-developed stochastic model introduced noise without detailed reaction steps.
- * A developed stochastic model incorporated detailed reaction steps.
- * The Gillespie method was used for numerical simulations of both stochastic models.
Main Results:
- * Robust circadian oscillations were observed even with reduced numbers of mRNA and nuclear proteins (tens and hundreds, respectively).
- * Both stochastic model versions yielded similar results.
- * Stochastic models showed good agreement with deterministic model predictions for circadian rhythms.
- * The influence of proximity to a bifurcation point was assessed.
Conclusions:
- * Stochastic simulations are crucial for understanding molecular noise effects in circadian rhythms at low molecule counts.
- * The developed and non-developed stochastic models provide reliable insights into circadian rhythm dynamics.
- * The findings support the robustness of circadian oscillations despite molecular fluctuations.
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