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A backtrack‐inducing sequence is an essential component of Escherichia coli σ 70 ‐dependent promoter‐proximal pausing
Author(s) -
Perdue Sarah A.,
Roberts Jeffrey W.
Publication year - 2010
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/j.1365-2958.2010.07347.x
Subject(s) - biology , rna polymerase , transcription (linguistics) , promoter , upstream activating sequence , genetics , sequence (biology) , escherichia coli , gene , gene expression , linguistics , philosophy
Summary RNA polymerase of both bacteria and eukaryotes can stall or pause within tens of base pairs of its initiation site at the promoter, a state that may reflect important regulatory events in early transcription. In the bacterial model system, the σ 70 initiation factor stabilizes such pauses by binding a downstream repeat of a promoter segment, especially the ‘−10’ promoter element. We first show here that the ‘−35’ promoter element also can stabilize promoter‐proximal pausing, through interaction with σ 70 region 4. We further show that an essential element of either type of pause is a sequence just upstream of the site of pausing that stabilizes RNA polymerase backtracking. Although the pause is not intrinsically backtracked, we suggest that the same sequence element is required both to stabilize the paused state and to potentiate backtracking.