论文标题
基因回路中噪声引起的过渡：一种缓慢噪声的扰动方法
Noise-induced transitions in gene circuits: a perturbative approach for slow noise
论文作者
论文摘要
我们考虑一类普通基因回路，受非线性外部噪声影响。为了解决这种非线性，我们基于假设噪声和基因动力学之间的时间尺度分离引入了一种一般的扰动方法，并且波动表现出较大但有限的相关时间。我们将此方法应用于拨动开关的情况，并考虑了与生物学相关的对数正态波动，我们发现该系统表现出噪声诱导的过渡。该系统在参数空间的区域中变为双峰，在该区域中，该系统在决定性方面是可决定的。我们表明，通过包含高阶校正，我们的方法可以使人们可以正确预测过渡的发生，即使对于波动的相关时间不多，也可以克服以前的理论方法的限制。有趣的是，我们发现，在中间噪声强度下，噪声引起的拨动开关中的过渡会影响涉及的一个基因，但不影响另一个基因。
We consider a generic class of gene circuits affected by nonlinear extrinsic noise. To address this nonlinearity we introduce a general perturbative methodology based on assuming timescale separation between noise and genes dynamics, with fluctuations exhibiting a large but finite correlation time. We apply this methodology to the case of the toggle switch, and by considering biologically relevant log-normal fluctuations, we find that the system exhibits noise-induced transitions. The system becomes bimodal in regions of the parameter space where it would be deterministically monostable. We show that by including higher order corrections our methodology allows one to obtain correct predictions for the occurrence of transitions even for not so large correlation time of the fluctuations, overcoming thereby limitations of previous theoretical approaches. Interestingly we find that at intermediate noise intensities the noise-induced transition in the toggle switch affects one of the genes involved, but not the other one.
