@article{BandyraSaidPfeifferetal.2012,
  author    = {Bandyra, Katarzyna J. and Said, Nelly and Pfeiffer, Verena and G{\´o}rna, Maria W. and Vogel, J{\"o}rg and Luisi, Ben F.},
  title     = {The Seed Region of a Small RNA Drives the Controlled Destruction of the Target mRNA by the Endoribonuclease RNase E},
  series = {Molecular Cell},
  volume    = {47},
  journal   = {Molecular Cell},
  number    = {6},
  doi       = {10.1016/j.molcel.2012.07.015},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126202},
  pages     = {943-953},
  year      = {2012},
  abstract  = {Numerous small non-coding RNAs (sRNAs) in bacteria modulate rates of translation initiation and degradation of target mRNAs, which they recognize through base-pairing facilitated by the RNA chaperone Hfq. Recent evidence indicates that the ternary complex of Hfq, sRNA and mRNA guides endoribonuclease RNase E to initiate turnover of both the RNAs. We show that a sRNA not only guides RNase E to a defined site in a target RNA, but also allosterically activates the enzyme by presenting a monophosphate group at the 5′-end of the cognate-pairing "seed." Moreover, in the absence of the target the 5′-monophosphate makes the sRNA seed region vulnerable to an attack by RNase E against which Hfq confers no protection. These results suggest that the chemical signature and pairing status of the sRNA seed region may help to both 'proofread' recognition and activate mRNA cleavage, as part of a dynamic process involving cooperation of RNA, Hfq and RNase E.},
  language  = {en}
}
@article{LioliouSharmaCaldelarietal.2012,
  author    = {Lioliou, Efthimia and Sharma, Cynthia M. and Caldelari, Isabelle and Helfer, Anne-Catherine and Fechter, Pierre and Vandenesch, Fran{\c{c}}ois and Vogel, J{\"o}rg and Romby, Pascale},
  title     = {Global Regulatory Functions of the Staphylococcus aureus Endoribonuclease III in Gene Expression},
  series = {PLoS Genetics},
  volume    = {8},
  journal   = {PLoS Genetics},
  number    = {6},
  doi       = {10.1371/journal.pgen.1002782},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127219},
  pages     = {e1002782},
  year      = {2012},
  abstract  = {RNA turnover plays an important role in both virulence and adaptation to stress in the Gram-positive human pathogen Staphylococcus aureus. However, the molecular players and mechanisms involved in these processes are poorly understood. Here, we explored the functions of S. aureus endoribonuclease III (RNase III), a member of the ubiquitous family of double-strand-specific endoribonucleases. To define genomic transcripts that are bound and processed by RNase III, we performed deep sequencing on cDNA libraries generated from RNAs that were co-immunoprecipitated with wild-type RNase III or two different cleavage-defective mutant variants in vivo. Several newly identified RNase III targets were validated by independent experimental methods. We identified various classes of structured RNAs as RNase III substrates and demonstrated that this enzyme is involved in the maturation of rRNAs and tRNAs, regulates the turnover of mRNAs and non-coding RNAs, and autoregulates its synthesis by cleaving within the coding region of its own mRNA. Moreover, we identified a positive effect of RNase III on protein synthesis based on novel mechanisms. RNase III-mediated cleavage in the 5′ untranslated region (5′UTR) enhanced the stability and translation of cspA mRNA, which encodes the major cold-shock protein. Furthermore, RNase III cleaved overlapping 5′UTRs of divergently transcribed genes to generate leaderless mRNAs, which constitutes a novel way to co-regulate neighboring genes. In agreement with recent findings, low abundance antisense RNAs covering 44\% of the annotated genes were captured by co-immunoprecipitation with RNase III mutant proteins. Thus, in addition to gene regulation, RNase III is associated with RNA quality control of pervasive transcription. Overall, this study illustrates the complexity of post-transcriptional regulation mediated by RNase III.},
  language  = {en}
}
@article{SchulteWestermannVogel2012,
  author    = {Schulte, Leon N. and Westermann, Alexander J. and Vogel, J{\"o}rg},
  title     = {Differential activation and functional specialization of miR-146 and miR-155 in innate immune sensing},
  edition   = {Advance Access},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76365},
  year      = {2012},
  abstract  = {Many microRNAs (miRNAs) are co-regulated during the same physiological process but the underlying cellular logic is often little understood. The conserved, immunomodulatory miRNAs miR-146 and miR-155, for instance, are co-induced in many cell types in response to microbial lipopolysaccharide (LPS) to feedback-repress LPS signalling through Toll-like receptor TLR4. Here, we report that these seemingly co-induced regulatory RNAs dramatically differ in their induction behaviour under various stimuli strengths and act non-redundantly through functional specialization; although miR-146 expression saturates at sub-inflammatory doses of LPS that do not trigger the messengers of inflammation markers, miR-155 remains tightly associated with the pro-inflammatory transcriptional programmes. Consequently, we found that both miRNAs control distinct mRNA target profiles; although miR-146 targets the messengers of LPS signal transduction components and thus downregulates cellular LPS sensitivity, miR-155 targets the mRNAs of genes pervasively involved in pro-inflammatory transcriptional programmes. Thus, miR-155 acts as a broad limiter of pro-inflammatory gene expression once the miR-146 dependent barrier to LPS triggered inflammation has been breached. Importantly, we also report alternative miR-155 activation by the sensing of bacterial peptidoglycan through cytoplasmic NOD-like receptor, NOD2. We predict that dosedependent responses to environmental stimuli may involve functional specialization of seemingly coinduced miRNAs in other cellular circuitries as well.},
  subject      = {Medizin},
  language  = {en}
}
@article{FroehlichPapenfortBergeretal.2012,
  author    = {Fr{\"o}hlich, Kathrin S. and Papenfort, Kai and Berger, Allison A. and Vogel, J{\"o}rg},
  title     = {A conserved RpoS-dependent small RNA controls the synthesis of major porin OmpD},
  series = {Nucleic Acids Research},
  volume    = {40},
  journal   = {Nucleic Acids Research},
  number    = {8},
  doi       = {10.1093/nar/gkr1156},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134230},
  pages     = {3623-3640},
  year      = {2012},
  abstract  = {A remarkable feature of many small non-coding RNAs (sRNAs) of Escherichia coli and Salmonella is their accumulation in the stationary phase of bacterial growth. Several stress response regulators and sigma factors have been reported to direct the transcription of stationary phase-specific sRNAs, but a widely conserved sRNA gene that is controlled by the major stationary phase and stress sigma factor, Sigma(S) (RpoS), has remained elusive. We have studied in Salmonella the conserved SdsR sRNA, previously known as RyeB, one of the most abundant stationary phase-specific sRNAs in E. coli. Alignments of the sdsR promoter region and genetic analysis strongly suggest that this sRNA gene is selectively transcribed by Sigma(S). We show that SdsR down-regulates the synthesis of the major Salmonella porin OmpD by Hfq-dependent base pairing; SdsR thus represents the fourth sRNA to regulate this major outer membrane porin. Similar to the InvR, MicC and RybB sRNAs, SdsR recognizes the ompD mRNA in the coding sequence, suggesting that this mRNA may be primarily targeted downstream of the start codon. The SdsR-binding site in ompD was localized by 3'-RACE, an experimental approach that promises to be of use in predicting other sRNA-target interactions in bacteria.},
  language  = {en}
}