Gill S C, Yager T D, von Hippel P H
Institute of Molecular Biology, University of Oregon, Eugene 97403.
Biophys Chem. 1990 Aug 31;37(1-3):239-50. doi: 10.1016/0301-4622(90)88023-l.
The E. coli RNA transcription cycle can be divided into three major phases, which are generally called initiation, elongation, and termination. In this paper, we review recent biophysical studies of the interactions of the transcriptional regulatory proteins, sigma 70 and NusA, with themselves and with core RNA polymerase in solution, as well as with core polymerase within the transcription complex. The different affinities of sigma 70 and NusA for core RNA polymerase at various stages in the transcription cycle, together with other quantitative data, are then used to construct a partial free energy diagram for the overall transcription process. This thermodynamic framework, which is interrupted by at least two irreversible steps, can be used to rationalize physiological aspects of the transcription cycle and its regulation, as well as to identify crucial points at which our knowledge is still incomplete.
大肠杆菌RNA转录循环可分为三个主要阶段，通常称为起始、延伸和终止。在本文中，我们综述了近期关于转录调节蛋白sigma 70和NusA在溶液中自身之间以及与核心RNA聚合酶相互作用，以及与转录复合物中核心聚合酶相互作用的生物物理研究。然后，利用sigma 70和NusA在转录循环不同阶段对核心RNA聚合酶的不同亲和力，以及其他定量数据，构建了整个转录过程的部分自由能图。这个被至少两个不可逆步骤中断的热力学框架，可用于解释转录循环及其调控的生理方面，以及识别我们的知识仍不完整的关键点。
