Shingler V
Department of Cell and Molecular Biology, Umeå University, Sweden.
Mol Microbiol. 1996 Feb;19(3):409-16. doi: 10.1046/j.1365-2958.1996.388920.x.
Transcription by RNA polymerase utilizing the alternative sigma factor beta 54 is regulated by a distinct class of positive activators designated the sigma 54-dependent family. The activities of these regulators are themselves modulated in response to a wide variety of environmental signals. Factors that modulate the expression or the activity of the regulatory protein in response to chemical and metabolic changes are ultimately responsible for determining the level of expression of sigma 54-dependent genes and hence the diverse bacterial functions that they encode. Many members of the sigma 54-dependent family are part of two-component sensor-response systems. This MicroReview emphasizes recent data concerning the activities of a distinct subgroup of the sigma 54-dependent regulators that directly sense and respond with transcriptional activation to the presence of small effector molecules in their environment. The functional consequences of effector activation in terms of regulation of the enzymatic (ATPase) activity of these transcriptional activators and interdomain interactions are discussed.
利用替代σ因子β54的RNA聚合酶转录受一类独特的正激活因子调控，这类正激活因子被称为σ54依赖性家族。这些调节因子的活性本身会根据多种环境信号进行调节。响应化学和代谢变化而调节调节蛋白表达或活性的因子最终决定了σ54依赖性基因的表达水平，进而决定了它们所编码的多种细菌功能。σ54依赖性家族的许多成员是双组分传感-响应系统的一部分。本微型综述重点介绍了有关σ54依赖性调节因子一个独特亚组活性的最新数据，该亚组能直接感知其环境中小效应分子的存在并通过转录激活作出反应。讨论了效应物激活在调节这些转录激活因子的酶活性（ATP酶）和结构域间相互作用方面的功能后果。
