Maity Alok Kumar, Bandyopadhyay Arnab, Chaudhury Pinaki, Banik Suman K
Department of Chemistry, University of Calcutta, 92 A P C Road, Kolkata 700 009, India.
Department of Chemistry, Bose Institute, 93/1 A P C Road, Kolkata 700 009, India.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Mar;89(3):032713. doi: 10.1103/PhysRevE.89.032713. Epub 2014 Mar 24.
We present a stochastic formalism for signal transduction processes in a bacterial two-component system. Using elementary mass action kinetics, the proposed model takes care of signal transduction in terms of a phosphotransfer mechanism between the cognate partners of a two-component system, viz., the sensor kinase and the response regulator. Based on the difference in functionality of the sensor kinase, the noisy phosphotransfer mechanism has been studied for monofunctional and bifunctional two-component systems using the formalism of the linear noise approximation. Steady-state analysis of both models quantifies different physically realizable quantities, e.g., the variance, the Fano factor (variance/mean), and mutual information. The resultant data reveal that both systems reliably transfer information of extracellular environment under low external stimulus and in a high-kinase-and-phosphatase regime. We extend our analysis further by studying the role of the two-component system in downstream gene regulation.
我们提出了一种用于细菌双组分系统中信号转导过程的随机形式体系。使用基本质量作用动力学，所提出的模型从双组分系统的同源伙伴（即传感器激酶和响应调节因子）之间的磷酸转移机制方面来处理信号转导。基于传感器激酶功能的差异，利用线性噪声近似形式体系对单功能和双功能双组分系统的噪声磷酸转移机制进行了研究。两个模型的稳态分析量化了不同的物理可实现量，例如方差、法诺因子（方差/均值）和互信息。所得数据表明，在低外部刺激和高激酶及磷酸酶状态下，两个系统都能可靠地传递细胞外环境信息。我们通过研究双组分系统在下游基因调控中的作用进一步扩展了分析。
