Targeting of <i>csgD</i> by the small regulatory RNA RprA links stationary phase, biofilm formation and cell envelope stress in <i>Escherichia coli</i>

Mika, Franziska; Busse, Susan; Possling, Alexandra; Berkholz, Janine; Tschowri, Natalia; Sommerfeldt, Nicole; Pruteanu, Mihaela; Hengge, Regine

doi:10.1111/j.1365-2958.2012.08002.x

Cited by 114 publications

(145 citation statements)

References 59 publications

(89 reference statements)

Supporting

Mentioning

143

Contrasting

Order By: Relevance

“…1C). We did not observe the previously reported RprA-mediated repression of csgD (35,36), perhaps because the csgD promoter was silent under the experimental conditions used here (37). This notwithstanding, our pulse expression data suggested that the two forms of RprA recognize several targets by different seed regions and predicted processed RprA to be a regulator in its own right.…”

Section: Resultscontrasting

confidence: 46%

“…Other environmental factors activating σ S independent of RprA will not affect RicI expression and plasmid transfer. In E. coli, a similar diversification of the σ S regulon is present with csgD and ydaM: although σ S activates these two genes for curli fiber and cellulose production, RprA represses their mRNAs (35,68), suggesting that RprA promotes certain stress-related functions of the σ S regulon but inhibits the functions of CsgD and YdaM.…”

Section: Discussionmentioning

confidence: 91%

See 1 more Smart Citation

Small RNA-based feedforward loop with AND-gate logic regulates extrachromosomal DNA transfer in Salmonella

Papenfort

Espinosa

Casadesús

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Horizontal gene transfer via plasmid conjugation is a major driving force in microbial evolution but constitutes a complex process that requires synchronization with the physiological state of the host bacteria. Although several host transcription factors are known to regulate plasmid-borne transfer genes, RNA-based regulatory circuits for host-plasmid communication remain unknown. We describe a posttranscriptional mechanism whereby the Hfq-dependent small RNA, RprA, inhibits transfer of pSLT, the virulence plasmid of Salmonella enterica. RprA employs two separate seed-pairing domains to activate the mRNAs of both the sigma-factor σ S and the RicI protein, a previously uncharacterized membrane protein here shown to inhibit conjugation. Transcription of ricI requires σ S and, together, RprA and σ S orchestrate a coherent feedforward loop with AND-gate logic to tightly control the activation of RicI synthesis. RicI interacts with the conjugation apparatus protein TraV and limits plasmid transfer under membrane-damaging conditions. To our knowledge, this study reports the first small RNA-controlled feedforward loop relying on posttranscriptional activation of two independent targets and an unexpected role of the conserved RprA small RNA in controlling extrachromosomal DNA transfer.RprA | sRNA | feedforward control | plasmid conjugation | Hfq

show abstract

Section: Resultscontrasting

confidence: 46%

Section: Discussionmentioning

confidence: 91%

Small RNA-based feedforward loop with AND-gate logic regulates extrachromosomal DNA transfer in Salmonella

Papenfort

Espinosa

Casadesús

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…In contrast, RprA is involved in up-regulation of its mRNA target, rpoS, through pairing to the 5 ′ UTR of rpoS, relieving the inhibitory secondary structure around the RBS and thereby supporting its translation (Updegrove et al 2008). Interestingly, RprA has recently been identified as being involved in down-regulation of two other mRNAs, namely, csgD and ydaM (Mika et al 2012). Hence while RprA protection from RNase E appears to be transmitted to its mRNA target, rpoS, to support up-regulation, the full picture is evidently complex with no immediate correlation between RNase E protection and sRNA function.…”

Section: Discussionmentioning

confidence: 99%

Hfq binding changes the structure ofEscherichia colismall noncoding RNAs OxyS and RprA, which are involved in the riboregulation ofrpoS

Henderson¹,

Vincent²,

Casamento³

et al. 2013

RNA

View full text Add to dashboard Cite

OxyS and RprA are two small noncoding RNAs (sRNAs) that modulate the expression of rpoS, encoding an alternative sigma factor that activates transcription of multiple Escherichia coli stress-response genes. While RprA activates rpoS for translation, OxyS down-regulates the transcript. Crucially, the RNA binding protein Hfq is required for both sRNAs to function, although the specific role played by Hfq remains unclear. We have investigated RprA and OxyS interactions with Hfq using biochemical and biophysical approaches. In particular, we have obtained the molecular envelopes of the Hfq-sRNA complexes using smallangle scattering methods, which reveal key molecular details. These data indicate that Hfq does not substantially change shape upon complex formation, whereas the sRNAs do. We link the impact of Hfq binding, and the sRNA structural changes induced, to transcript stability with respect to RNase E degradation. In light of these findings, we discuss the role of Hfq in the opposing regulatory functions played by RprA and OxyS in rpoS regulation.

show abstract

“…OmrA, OmrB, RprA, GcvB, and McaS all bind upstream of the ribosome-binding site and their mode of action likely involves inhibition of translational initiation and/or mRNA destabilization (Holmqvist et al, 2010;Jørgensen et al, 2012;Mika et al, 2012;Thomason et al, 2012).…”

Section: Introductionmentioning

confidence: 99%

Phage insertion in mlrA and variations in rpoS limit curli expression and biofilm formation in Escherichia coli serotype O157 : H7

et al. 2013

View full text Add to dashboard Cite

Biofilm formation in Escherichia coli is a tightly controlled process requiring the expression of adhesive curli fibres and certain polysaccharides such as cellulose. The transcriptional regulator CsgD is central to biofilm formation, controlling the expression of the curli structural and export proteins and the diguanylate cyclase adrA, which indirectly activates cellulose production. CsgD itself is highly regulated by two sigma factors (RpoS and RpoD), multiple DNA-binding proteins, small regulatory RNAs and several GGDEF/EAL proteins acting through c-di-GMP. One such transcription factor MlrA binds the csgD promoter to enhance the RpoS-dependent transcription of csgD. Bacteriophage, often carrying the stx 1 gene, utilize an insertion site in the proximal mlrA coding region of E. coli serotype O157 : H7 strains, and the loss of mlrA function would be expected to be the major factor contributing to poor curli and biofilm expression in that serotype. Using a bank of 55 strains of serotype O157 : H7, we investigated the consequences of bacteriophage insertion. Although curli/biofilm expression was restored in many of the prophagebearing strains by a wild-type copy of mlrA on a multi-copy plasmid, more than half of the strains showed only partial or no complementation. Moreover, the two strains carrying an intact mlrA were found to be deficient in biofilm formation. However, RpoS mutations that attenuated or inactivated RpoS-dependent functions such as biofilm formation were found in .70 % of the strains, including the two strains with an intact mlrA. We conclude that bacteriophage interruption of mlrA and RpoS mutations provide major obstacles limiting curli expression and biofilm formation in most serotype O157 : H7 strains.

show abstract

Targeting of csgD by the small regulatory RNA RprA links stationary phase, biofilm formation and cell envelope stress in Escherichia coli

Cited by 114 publications

References 59 publications

Small RNA-based feedforward loop with AND-gate logic regulates extrachromosomal DNA transfer in Salmonella

Small RNA-based feedforward loop with AND-gate logic regulates extrachromosomal DNA transfer in Salmonella

Hfq binding changes the structure ofEscherichia colismall noncoding RNAs OxyS and RprA, which are involved in the riboregulation ofrpoS

Phage insertion in mlrA and variations in rpoS limit curli expression and biofilm formation in Escherichia coli serotype O157 : H7

Contact Info

Product

Resources

About