Mechanism of Bacterial Transcription Initiation: RNA Polymerase - Promoter Binding, Isomerization to Initiation-Competent Open Complexes, and Initiation of RNA Synthesis

JOURNAL OF MOLECULAR BIOLOGY

卷:412

Review

Saecker, Ruth M.²  Record, M. Thomas^2,3  deHaseth, Pieter L.^1,4 

[1] Case Western Reserve Univ, Ctr RNA Mol Biol, Sch Med, Cleveland, OH 44106 USA

[2] Univ Wisconsin, Dept Biochem, Madison, WI 53706 USA

[3] Univ Wisconsin, Dept Chem, Madison, WI 53706 USA

[4] Case Western Reserve Univ, Dept Biochem, Cleveland, OH 44106 USA

关键词: RNA polymerase;    Promoter;    Sigma factor;    Transcription initiation;    Intermediate complexes;   

DOI  :  10.1016/j.jmb.2011.01.018

来源: Elsevier

【 摘 要 】

Initiation of RNA synthesis from DNA templates by RNA polymerase (RNAP) is a multi-step process, in which initial recognition of promoter DNA by RNAP triggers a series of conformational changes in both RNAP and promoter DNA. The bacterial RNAP functions as a molecular isomerization machine, using binding free energy to remodel the initial recognition complex, placing downstream duplex DNA in the active site cleft and then separating the nontemplate and template strands in the region surrounding the start site of RNA synthesis. In this initial unstable open complex the template strand appears correctly positioned in the active site. Subsequently, the nontemplate strand is repositioned and a clamp is assembled on duplex DNA downstream of the open region to form the highly stable open complex, RPo. The transcription initiation factor, sigma(70), plays critical roles in promoter recognition and RPo formation as well as in early steps of RNA synthesis. (C) 2011 Elsevier Ltd. All rights reserved.

【 授权许可】

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