Noise Characteristics of Molecular Oscillations in Simple Genetic Oscillatory Systems

TL;DR

This study investigates the stochastic noise characteristics in genetic oscillatory systems, focusing on fluctuations in oscillation periods and amplitudes using the repressilator model and Monte Carlo simulations.

Contribution

It provides a detailed analysis of noise propagation and fluctuation distributions in simple genetic oscillators, highlighting differences between amplitude and period variability.

Findings

Amplitude fluctuations are larger than period fluctuations.

Oscillation period distribution fits Weibull distribution.

Amplitude distribution has a Gaussian tail.

Abstract

We study the noise characteristics of stochastic oscillations in protein number dynamics of simple genetic oscillatory systems. Using the three-component negative feedback transcription regulatory system called the repressilator as a prototypical example, we quantify the degree of fluctuations in oscillation periods and amplitudes, as well as the noise propagation along the regulatory cascade in the stable oscillation regime via dynamic Monte Carlo simulations. For the single protein-species level, the fluctuation in the oscillation amplitudes is found to be larger than that of the oscillation periods, the distributions of which are reasonably described by the Weibull distribution and the Gaussian tail, respectively. Correlations between successive periods and between successive amplitudes, respectively, are measured to assess the noise propagation properties, which are found to decay faster for the amplitude than for the period. The local fluctuation property is also studied.