Abstract

The transcription factors, such as activators and repressors, can interact with the promoter of gene either in a competitive or non-competitive way. In this paper, we construct a stochastic model with non-competitive transcriptional regulatory architecture and develop an analytical theory that re-establishes the experimental results with an improved data fitting. The analytical expressions in the theory allow us to study the nature of the system corresponding to any of its parameters and hence, enable us to find out the factors that govern the regulation of gene expression for that architecture. We notice that, along with transcriptional reinitiation and repressors, there are other parameters that can control the noisiness of this network. We also observe that, the Fano factor (at mRNA level) varies from sub-Poissonian regime to super-Poissonian regime. In addition to the aforementioned properties, we observe some anomalous characteristics of the Fano factor (at mRNA level) and that of the variance of protein at lower activator concentrations in the presence of repressor molecules. This model is useful to understand the architecture of interactions which may buffer the stochasticity inherent to gene transcription.

Graphical abstract

中文翻译：

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具有非竞争性转录调控结构的随机基因转录

摘要

转录因子，如激活因子和抑制因子，可以以竞争或非竞争的方式与基因的启动子相互作用。在本文中，我们构建了一个具有非竞争性转录调控架构的随机模型，并开发了一种分析理论，该理论通过改进的数据拟合重新建立了实验结果。理论中的分析表达式使我们能够研究与其任何参数相对应的系统的性质，从而使我们能够找出控制该架构基因表达调控的因素。我们注意到，除了转录重新启动和阻遏物外，还有其他参数可以控制该网络的噪音。我们还观察到，Fano 因子（在 mRNA 水平）从亚泊松状态到超泊松状态变化。除了上述特性外，我们还观察到 Fano 因子（在 mRNA 水平）的一些异常特征，以及在存在抑制分子的情况下，在较低激活剂浓度下蛋白质的变化。该模型有助于理解可能缓冲基因转录固有的随机性的相互作用的结构。

图形概要