Tunability and Noise Dependence in Differentiation Dynamics

TLDR

Differentiation dynamics depend on genetic circuit architecture, quantitative parameters, and noise. The study aims to clarify how architecture, parameters, and noise jointly control cellular behavior. The authors examined Bacillus subtilis competence by analyzing probabilistic differentiation and experimentally reducing global noise to assess its effect on differentiation frequency. Key parameters independently tune competence frequency and duration, enabling oscillatory regimes; architectural changes sharpen event precision, and reduced noise correlates with differentiation frequency, demonstrating a resilient, tunable, noise‑dependent circuit.

Abstract

The dynamic process of differentiation depends on the architecture, quantitative parameters, and noise of underlying genetic circuits. However, it remains unclear how these elements combine to control cellular behavior. We analyzed the probabilistic and transient differentiation of Bacillus subtilis cells into the state of competence. A few key parameters independently tuned the frequency of initiation and the duration of competence episodes and allowed the circuit to access different dynamic regimes, including oscillation. Altering circuit architecture showed that the duration of competence events can be made more precise. We used an experimental method to reduce global cellular noise and showed that noise levels are correlated with frequency of differentiation events. Together, the data reveal a noise-dependent circuit that is remarkably resilient and tunable in terms of its dynamic behavior.