噪声诱导p53基因调控网络的双稳态转迁

Noise-induced bi-stable transition in p53 gene regulatory network

在p53基因调控网络的确定模型中加入高斯白噪声,针对确定模型的双稳态区间参数,利用时间序列、能量面和平均值的方法,分析噪声对双稳态转迁的影响。结果显示,对于只有低(高)稳态的鞍结分岔点附近的参数,噪声将高(低)稳态转迁到低(高)稳态,而对于远离分岔点的参数,噪声诱导两个稳态间的不断转迁,能量面解释了转迁的原理。p53浓度的平均值显示低稳态易转迁到高稳态,但高稳态很难转迁到低稳态。

In this study,Gaussian white noise was added to the deterministic model of the p53 gene regulatory network and the effect of noise on bistable transitions in stochastic model was analyzed for different bifurcation parameters in the bistable intervals of the deterministic model using the time series,potential landscape and average concentration methods.It is found that the system switches from high(low)steady state to low(high)steady state induced by noise when the parameter is close to the saddle-node bifurcation point near the low(high)steady state.However,for parameters far from the bifurcation point,noise leads to the continuous transitions between these two steady states all the times.The reasons why the switch appears is explained by the potential landscapes.In addition,the average concentrations of p53 indicate that it is easy to switch from a low stable state to a high one for the system,but it is difficult to transit from a high steady state to a low one.