Common and divergent features in transcriptional control of the homologous small RNAs GlmY and GlmZ in Enterobacteriaceae.
Small RNAs GlmY and GlmZ compose a cascade that feedback-regulates synthesis of enzyme GlmS in Enterobacteriaceae. Here, we analyzed the transcriptional regulation of glmY/glmZ from Yersinia pseudotuberculosis, Salmonella typhimurium and Escherichia coli, as representatives for other enterobacterial species, which exhibit similar promoter architectures. The GlmY and GlmZ sRNAs of Y. pseudotuberculosis are transcribed from σ(54)-promoters that require activation by the response regulator GlrR through binding to three conserved sites located upstream of the promoters. This also applies to glmY/glmZ of S. typhimurium and glmY of E. coli, but as a difference additional σ(70)-promoters overlap the σ(54)-promoters and initiate transcription at the same site. In contrast, E. coli glmZ is transcribed from a single σ(70)-promoter. Thus, transcription of glmY and glmZ is controlled by σ(54) and the two-component system GlrR/GlrK (QseF/QseE) in Y. pseudotuberculosis and presumably in many other Enterobacteria. However, in a subset of species such as E. coli this relationship is partially lost in favor of σ(70)-dependent transcription. In addition, we show that activity of the σ(54)-promoter of E. coli glmY requires binding of the integration host factor to sites upstream of the promoter. Finally, evidence is provided that phosphorylation of GlrR increases its activity and thereby sRNA expression.
Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August-University, Grisebachstrasse 8, 37077 Göttingen, Germany.
Yvonne
Y
Göpel
Denise
D
Lüttmann
Ann Kathrin
AK
Heroven
Birte
B
Reichenbach
Petra
P
Dersch
Boris
B
Görke
D001426:Bacterial Proteins / Q000378:metabolism; D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000378:metabolism; D004755:Enterobacteriaceae / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D034982:Integration Host Factors / Q000378:metabolism; D011401:Promoter Regions, Genetic; D051877:RNA Polymerase Sigma 54 / Q000378:metabolism; D012329:RNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D058727:RNA, Small Untranslated / Q000235:genetics* / Q000378:metabolism; D012486:Salmonella typhimurium / Q000235:genetics / Q000378:metabolism; D026801:Synteny; D014158:Transcription, Genetic; D015011:Yersinia pseudotuberculosis / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D034982:Integration Host Factors; D012329:RNA, Bacterial; D058727:RNA, Small Untranslated; D051877:RNA Polymerase Sigma 54