大肠杆菌转录因子通过一种通用的稳态机制调节启动子活性，这一成果由
研究人员证明了启动子的基础活性与给定TF的调节之间的反比标关系。具体来说，在更强的启动子上，激活更弱，抑制更强。这种缩放适用于激活因子和抑制因子，这表明了一种共同的潜在机制，即TF通过稳定RNAP在启动子上的结合来调节表达。这种关系的结果是，TF通过影响不同基础活性启动子的恒定调节表达水平来缓冲表达，从而确保在遗传或环境变化的情况下保持稳态控制。
据了解，转录因子（TF）可以通过不同机制的相互作用激活或抑制基因表达，包括RNA聚合酶（RNAP）的募集、排斥和起始。然而，根据受调节的启动子身份，TF功能可能会发生变化，并且这种上下文依赖性的原理尚不清楚。
附：英文原文
Title: E. coli transcription factors regulate promoter activity by a universal, homeostatic mechanism
Author: Vinuselvi Parisutham, Sunil Guharajan, Melina Lian, Md Zulfikar Ali, Hannah Rogers, Shannon Joyce, Mariana Noto Guillen, Robert C. Brewster
Issue&Volume: 2025-09-11
Abstract: Transcription factors (TFs) may activate or repress gene expression through an interplay of different mechanisms, including RNA polymerase (RNAP) recruitment, exclusion, and initiation. However, depending on the regulated promoter identity, TF function can vary, and the principles underlying this context dependence remain unclear. We demonstrate an inverse scaling relationship between the promoter’s basal activity and its regulation by a given TF. Specifically, activation is weaker and repression is stronger on stronger promoters. This scaling applies to both activators and repressors, which suggests a common underlying mechanism where TFs regulate expression by stabilizing RNAP binding at the promoter. The consequence of this relationship is that TFs buffer expression by affecting constant regulated expression levels across promoters of different basal activity, ensuring homeostatic control despite genetic or environmental changes.
DOI: adv2064
Source: https://www.science.org/doi/10.1126/science.adv2064