基因转录调控系统中的色噪声诱导转化研究

Colored noise induced switch in the gene transcriptional regulatory system

研究了基因转录调控系统中的色噪声诱导蛋白质浓度转换现象.据Novikov定理和Fox近似方法得到相应的Fokker-Planck方程,给出稳态概率分布函数、蛋白质浓度平均值及其平均首通时间的近似表达式,分析了噪声的自关联时间对稳态概率、平均值和平均首通时间的影响.研究表明,分解率的噪声的自关联时间引起蛋白质的浓度经历了"关"→"开"的转换;合成率的噪声的自关联时间引起蛋白质的浓度经历了"开"→"关"转换.然而,随着两种自关联时间的增大,平均首通时间增大,即蛋白质浓度之间的转换变得困难.数值模拟结果与理论预测基本符合.

The colored noise induced switch in the gene transcriptional regulatory system is investigated.The approximate Fokker-Planck equation is obtained based on the Novikov theorem and the Fox approach.The explicit expressions of the steady state probability distribution,the mean value,and the mean first passage time are derived.After the numerical computations,these results show that the TF-A monomer concentration switches from the ＂off＂ position to the ＂on＂ position with the self-correlation time of the multiplicative noise increasing.The TF-A monomer concentration switches from the ＂on＂ position to the ＂off position with the self-correlation time of the additive noise increasing.With the two kinds of the self-correlation time increasing,the mean first passage time becomes large, namely,the TF-A monomer concentration switch becomes difficult.The theoretical predictions are found to be in basic agreement with numerical results.