AI 中文总结
研究基因调控回路中反馈拓扑对随机波动的控制，通过建立理论框架，识别出循环噪声，揭示其与波动持续性的关系，为理解反馈结构调节噪声大小和持续性提供最小框架。
AI 中文摘要
反馈在控制多种细胞功能的生化网络中起着重要作用，然而反馈拓扑如何控制随机波动仍未完全理解。本文为双节点反馈基序建立理论框架，在线性噪声近似下，识别出由回路闭合产生的对节点波动的反馈驱动贡献，即循环噪声。其符号和大小决定反馈增强或减弱节点波动。还表明反馈介导的噪声循环在稳态自相关衰减中留下时间特征，揭示回路闭合如何改变波动持续性，为理解反馈结构如何调节基因调控回路中噪声的大小和时间持续性提供了最小框架。
英文摘要
Feedback plays a significant role in biochemical networks that govern a multitude of cellular functions, including development, adaptation, and homeostasis. Yet, how feedback topology controls stochastic fluctuations remains incompletely understood. Here, we develop a theoretical framework for two-node feedback motifs composed of activating and repressive regulatory interactions between two transcription factors. Under the linear noise approximation, we identify a feedback-driven contribution to node-wise fluctuations, termed cyclic noise, that arises specifically from loop closure. Cyclic noise is the component of fluctuations that circulates through the regulatory circuit. Its sign and magnitude distinguish whether feedback amplifies or attenuates node-wise fluctuations. We further show that feedback-mediated noise circulation leaves a temporal signature in the decay of steady-state autocorrelation, revealing how loop closure modifies the persistence of fluctuations. We thus provide a minimal framework for understanding how feedback architecture regulates both the magnitude and the temporal persistence of noise in gene regulatory circuits.
Comments12 pages, 7 figures
