Kooperativer Bibliotheksverbund

Berlin Brandenburg

You have 0 saved results.
Mark results and click the "Add To Watchlist" link in order to add them to this list.
and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Hfq
Type of Medium
Language
Year
  • 1
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 25 August 2015, Vol.112(34), pp.E4772-81
    Description: 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.
    Keywords: Hfq ; Rpra ; Feedforward Control ; Plasmid Conjugation ; Srna ; Chromosomes, Bacterial ; DNA, Bacterial -- Genetics ; RNA, Bacterial -- Genetics ; Salmonella -- Genetics
    ISSN: 00278424
    E-ISSN: 1091-6490
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 11 October 2016, Vol.113(41), pp.11591-11596
    Description: The functional annotation of transcriptomes and identification of noncoding RNA (ncRNA) classes has been greatly facilitated by the advent of next-generation RNA sequencing which, by reading the nucleotide order of transcripts, theoretically allows the rapid profiling of all transcripts in a cell. However, primary sequence per se is a poor predictor of function, as ncRNAs dramatically vary in length and structure and often lack identifiable motifs. Therefore, to visualize an informative RNA landscape of organisms with potentially new RNA biology that are emerging from microbiome and environmental studies requires the use of more functionally relevant criteria. One such criterion is the association of RNAs with functionally important cognate RNA-binding proteins. Here we analyze the full ensemble of cellular RNAs using gradient profiling by sequencing (Grad-seq) in the bacterial pathogen Salmonella enterica, partitioning its coding and noncoding transcripts based on their network of RNA-protein interactions. In addition to capturing established RNA classes based on their biochemical profiles, the Grad-seq approach enabled the discovery of an overlooked large collective of structured small RNAs that form stable complexes with the conserved protein ProQ. We show that ProQ is an abundant RNA-binding protein with a wide range of ligands and a global influence on Salmonella gene expression. Given its generic ability to chart a functional RNA landscape irrespective of transcript length and sequence diversity, Grad-seq promises to define functional RNA classes and major RNA-binding proteins in both model species and genetically intractable organisms.
    Keywords: Hfq ; Proq ; RNA–Protein Interaction ; Noncoding RNA ; Small RNA ; Bacterial Proteins -- Metabolism ; High-Throughput Nucleotide Sequencing -- Methods ; RNA, Bacterial -- Metabolism ; RNA-Binding Proteins -- Metabolism ; Salmonella Enterica -- Metabolism
    ISSN: 00278424
    E-ISSN: 1091-6490
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    In: EMBO Journal, 03 June 2015, Vol.34(11), pp.1478-1492
    Description: There is an expanding list of examples by which one can posttranscriptionally influence the expression of others. This can involve sponges that sequester regulatory s of s in the same regulon, but the underlying molecular mechanism of such cross talk remains little understood. Here, we report sponge‐mediated cross talk in the posttranscriptional network of GcvB, a conserved Hfq‐dependent small with one of the largest regulons known in bacteria. We show that decay from the locus encoding an amino acid transporter generates a stable fragment (SroC) that base‐pairs with GcvB. This interaction triggers the degradation of GcvB by ase E, alleviating the GcvB‐mediated repression of other amino acid‐related transport and metabolic genes. Intriguingly, since the itself is a target of GcvB, the SroC sponge seems to enable both an internal feed‐forward loop to activate its parental in and activation of many ‐encoded s in the same pathway. Disabling this cross talk affects bacterial growth when peptides are the sole carbon and nitrogen sources. Decay of the bacterial GcvB , which keeps it from regulating its targets, is triggered by a 3′‐‐derived fragment from a target . This ability of s to compete for regulatory interaction presents a new mode of cross talk in bacteria. . Decay of the bacterial GcvB s, which keeps it from regulating its m targets, is triggered by a 3′‐‐derived fragment from a target m. This ability of ms to compete for regulatory interaction presents a new mode of cross talk in bacteria.
    Keywords: G Cv B ; H Fq ; Noncoding Rna ; Rn Ase E ; S Ro C
    ISSN: 0261-4189
    E-ISSN: 1460-2075
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: EMBO journal: European Molecular Biology Organization, 2015, Issue 11, pp.1478-1492
    Description: There is an expanding list of examples by which one mRNA can posttranscriptionally influence the expression of others. This can involve RNA sponges that sequester regulatory RNAs of mRNAs in the same regulon, but the underlying molecular mechanism of such mRNA cross talk remains little understood. Here, we report sponge-mediated mRNA cross talk in the posttranscriptional network of GcvB, a conserved Hfq-dependent small RNA with one of the largest regulons known in bacteria. We show that mRNA decay from the gltIJKL locus encoding an amino acid ABC transporter generates a stable fragment (SroC) that base-pairs with GcvB. This interaction triggers the degradation of GcvB by RNase E, alleviating the GcvB-mediated mRNA repression of other amino acid-related transport and metabolic genes. Intriguingly, since the gltIJKL mRNA itself is a target of GcvB, the SroC sponge seems to enable both an internal feed-forward loop to activate its parental mRNA in cis and activation of many trans-encoded mRNAs in the same pathway. Disabling this mRNA cross talk affects bacterial growth when peptides are the sole carbon and nitrogen sources.
    Keywords: Gcvb ; Hfq ; Noncoding Rna ; Rnase E ; Sroc
    ISSN: 0261-4189
    Source: Fundación Dialnet
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    In: EMBO Journal, 17 October 2012, Vol.31(20), pp.4005-4019
    Description: The small RNAs associated with the protein Hfq constitute one of the largest classes of post‐transcriptional regulators known to date. Most previously investigated members of this class are encoded by conserved free‐standing genes. Here, deep sequencing of Hfq‐bound transcripts from multiple stages of growth of revealed a plethora of new small RNA species from within mRNA loci, including DapZ, which overlaps with the 3′ region of the biosynthetic gene, . Synthesis of the DapZ small RNA is independent of DapB protein synthesis, and is controlled by HilD, the master regulator of invasion genes. DapZ carries a short G/U‐rich domain similar to that of the globally acting GcvB small RNA, and uses GcvB‐like seed pairing to repress translation of the major ABC transporters, DppA and OppA. This exemplifies double functional output from an mRNA locus by the production of both a protein and an Hfq‐dependent ‐acting RNA. Our atlas of Hfq targets suggests that the 3′ regions of mRNA genes constitute a rich reservoir that provides the Hfq network with new regulatory small RNAs. Deep sequencing of Hfq‐binding RNAs isolated from at different growth stages reveals that the 3′ UTR of bacterial mRNAs are a rich source of regulatory small RNAs which modulate gene expression in trans.
    Keywords: Abc Transporter ; Dapz ; Gcvb ; Hfq ; 3′ Utr
    ISSN: 0261-4189
    E-ISSN: 1460-2075
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    In: EMBO Journal, 13 November 2013, Vol.32(22), pp.2963-2979
    Description: Small RNAs use a diversity of well‐characterized mechanisms to repress mRNAs, but how they activate gene expression at the mRNA level remains not well understood. The predominant activation mechanism of Hfq‐associated small RNAs has been translational control whereby base pairing with the target prevents the formation of an intrinsic inhibitory structure in the mRNA and promotes translation initiation. Here, we report a translation‐independent mechanism whereby the small RNA RydC selectively activates the longer of two isoforms of mRNA (encoding cyclopropane fatty acid synthase) in . Target activation is achieved through seed pairing of the pseudoknot‐exposed, conserved 5′ end of RydC to an upstream region of the mRNA. The seed pairing stabilizes the messenger, likely by interfering directly with RNase E‐mediated decay in the 5′ untranslated region. Intriguingly, this mechanism is generic such that the activation is equally achieved by seed pairing of unrelated small RNAs, suggesting that this mechanism may be utilized in the design of RNA‐controlled synthetic circuits. Physiologically, RydC is the first small RNA known to regulate membrane stability. The small RNA RydC stabilizes target mRNAs in a translation‐independent manner through base pairing to the 5′UTR, blocking RNase E access. Cyclopropane fatty acid synthase is a target for RydC, providing the first link between sRNA regulation and membrane biosynthesis in bacteria.
    Keywords: Fatty Acid Synthesis ; Hfq ; Mrna Activation ; Noncoding Rna ; Small Rna
    ISSN: 0261-4189
    E-ISSN: 1460-2075
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Language: English
    In: Molecular Cell, 04 February 2016, Vol.61(3), pp.352-363
    Description: Small RNAs (sRNAs) from conserved noncoding genes are crucial regulators in bacterial signaling pathways but have remained elusive in the Cpx response to inner membrane stress. Here we report that an alternative biogenesis pathway releasing the conserved mRNA 3′ UTR of stress chaperone CpxP as an ∼60-nt sRNA provides the noncoding arm of the Cpx response. This so-called CpxQ sRNA, generated by general mRNA decay through RNase E, acts as an Hfq-dependent repressor of multiple mRNAs encoding extracytoplasmic proteins. Both CpxQ and the Cpx pathway are required for cell survival under conditions of dissipation of membrane potential. Our discovery of CpxQ illustrates how the conversion of a transcribed 3′ UTR into an sRNA doubles the output of a single mRNA to produce two factors with spatially segregated functions during inner membrane stress: a chaperone that targets problematic proteins in the periplasm and a regulatory RNA that dampens their synthesis in the cytosol. Chao and Vogel discover that a small RNA cleaved off the 3′ end of an mRNA provides the elusive regulatory noncoding arm of the bacterial Cpx response to inner membrane stress.
    Keywords: Cpx Pathway ; Cpxp ; Cpxq ; 3′ Utr ; Hfq ; Rnase E ; Noncoding RNA ; Nhab ; Envelope Stress ; Membrane Potential ; Biology
    ISSN: 1097-2765
    E-ISSN: 1097-4164
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Language: English
    In: Frontiers in cellular and infection microbiology, 2014, Vol.4, pp.91
    Description: Enteric pathogens often cycle between virulent and saprophytic lifestyles. To endure these frequent changes in nutrient availability and composition bacteria possess an arsenal of regulatory and metabolic genes allowing rapid adaptation and high flexibility. While numerous proteins have been characterized with regard to metabolic control in pathogenic bacteria, small non-coding RNAs have emerged as additional regulators of metabolism. Recent advances in sequencing technology have vastly increased the number of candidate regulatory RNAs and several of them have been found to act at the interface of bacterial metabolism and virulence factor expression. Importantly, studying these riboregulators has not only provided insight into their metabolic control functions but also revealed new mechanisms of post-transcriptional gene control. This review will focus on the recent advances in this area of host-microbe interaction and discuss how regulatory small RNAs may help coordinate metabolism and virulence of enteric pathogens.
    Keywords: Csra ; Hfq ; Carbon Metabolism ; Srna ; Virulence ; Energy Metabolism ; Carbon -- Metabolism ; Intestines -- Microbiology ; RNA, Small Untranslated -- Genetics
    E-ISSN: 2235-2988
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Language: English
    In: Annual review of genetics, 2015, Vol.49, pp.367-94
    Description: Over the past decade, bacterial small RNAs (sRNAs) have gone from a biological curiosity to being recognized as a major class of regulatory molecules. High-throughput methods for sampling the transcriptional output of bacterial cells demonstrate that sRNAs are universal features of bacterial transcriptomes, are plentiful, and appear to vary extensively over evolutionary time. With ever more bacteria coming under study, the question becomes how can we accelerate the discovery and functional characterization of sRNAs in diverse organisms. New technologies built on high-throughput sequencing are emerging that can rapidly provide global insight into the numbers and functions of sRNAs in bacteria of interest, providing information that can shape hypotheses and guide research. In this review, we describe recent developments in transcriptomics (RNA-seq) and functional genomics that we expect to help us develop an integrated, systems-level view of sRNA biology in bacteria.
    Keywords: Hfq ; RNA-Seq ; Tradis ; High-Throughput Technology ; Noncoding RNA ; Phenotype Mapping ; Ribosome Profiling ; Small RNA ; RNA, Bacterial -- Analysis ; RNA, Small Untranslated -- Analysis ; Sequence Analysis, RNA -- Methods
    ISSN: 00664197
    E-ISSN: 1545-2948
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Language: English
    In: Genes & development, 15 May 2013, Vol.27(10), pp.1073-8
    Description: The abundant RNA-binding proteins CsrA and Hfq each impact bacterial physiology by working in conjunction with small RNAs to control large post-transcriptional regulons. The small RNAs involved were considered mechanistically distinct, regulating mRNAs either directly through Hfq-mediated base-pairing or indirectly by sequestering the global translational repressor CsrA. In this issue of Genes & Development, Jørgensen and colleagues (pp. 1132-1145) blur these distinctions with a dual-mechanism small RNA that acts through both Hfq and CsrA to regulate the formation of bacterial biofilms.
    Keywords: Csra ; Csrb ; Hfq ; Pga ; C-Di-Gmp ; Gene Expression Regulation, Bacterial ; Biofilms -- Growth & Development ; Escherichia Coli -- Genetics ; RNA, Bacterial -- Genetics
    ISSN: 08909369
    E-ISSN: 1549-5477
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages