RRC ID 35378
著者 Ionescu M, Elgrably-Weiss M, Elad T, Rasouly A, Yagur-Kroll S, Belkin S.
タイトル Negative regulation of σ(70)-driven promoters by σ(70).
ジャーナル Res Microbiol
Abstract The Escherichia coli yjbEFGH operon, encoding genes involved in exopolysaccharide production, has previously been shown to be induced by osmotic stress and to be negatively regulated by σ(38). Promoter analysis suggested that like most E. coli genes, its transcription is driven by the housekeeping sigma factor σ(70). Indeed, manipulation of any of the other five alternative sigma factors did not affect its induction by osmotic stress. Surprisingly, when assayed in a strain expressing low levels of σ(70), yjbEFGH induction in response to osmotic stress was higher than in a strain expressing normal levels of σ(70). Similar phenomena were observed in the σ(70)-driven promoters of sulA, uvrA, recA, fecI, entC and lacZ, the transcription of which is directly controlled by a repressor protein (LexA, Fur and LacI), but not in promoters of the housekeeping genes ftsA and ftsY, or in σ(38)-driven treA promoter. Since transcription factors are generally present in the cell in low numbers, we hypothesize that a decrease in σ(70), that drives the expression of lexA, fur and lacI as well, further diminishes their number in the cell and thus de-represses the induction of genes which are subjected to their repression.
巻・号 162(5)
ページ 461-9
公開日 2011-6-1
DOI 10.1016/j.resmic.2011.03.005
PII S0923-2508(11)00048-9
PMID 21396442
MeSH DNA-Directed RNA Polymerases / genetics* DNA-Directed RNA Polymerases / metabolism Down-Regulation* Escherichia coli / genetics* Escherichia coli / metabolism Escherichia coli Proteins / genetics* Escherichia coli Proteins / metabolism Gene Expression Regulation, Bacterial* Operon Promoter Regions, Genetic* Sigma Factor / genetics* Sigma Factor / metabolism
IF 3.217
引用数 2
WOS 分野 MICROBIOLOGY
リソース情報
原核生物(大腸菌) JW1907-KC JW3169-KC JW4555-KC?