title: Identification of bacteriophage-encoded anti-sRNAs in pathogenic Escherichia coli.
abstract: In bacteria, Hfq is a core RNA chaperone that catalyzes the interaction of mRNAs with regulatory small RNAs (sRNAs). To determine in vivo RNA sequence requirements for Hfq interactions, and to study riboregulation in a bacterial pathogen, Hfq was UV crosslinked to RNAs in enterohemorrhagic Escherichia coli (EHEC). Hfq bound repeated trinucleotide motifs of A-R-N (A-A/G-any nucleotide) often associated with the Shine-Dalgarno translation initiation sequence in mRNAs. These motifs overlapped or were adjacent to the mRNA sequences bound by sRNAs. In consequence, sRNA-mRNA duplex formation will displace Hfq, promoting recycling. Fifty-five sRNAs were identified within bacteriophage-derived regions of the EHEC genome, including some of the most abundant Hfq-interacting sRNAs. One of these (AgvB) antagonized the function of the core genome regulatory sRNA, GcvB, by mimicking its mRNA substrate sequence. This bacteriophage-encoded "anti-sRNA" provided EHEC with a growth advantage specifically in bovine rectal mucus recovered from its primary colonization site in cattle.
authors.affiliation: Wellcome Trust Centre for Cell Biology, The University of Edinburgh, Edinburgh EH9 3JR, UK; The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK.
authors.forename: Jai J
authors.initials: JJ
authors.lastname: Tree
authors.affiliation: Wellcome Trust Centre for Cell Biology, The University of Edinburgh, Edinburgh EH9 3JR, UK; Centre for Synthetic and Systems Biology (SynthSys), University of Edinburgh, Edinburgh EH9 3JD, UK.
authors.forename: Sander
authors.initials: S
authors.lastname: Granneman
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK.
authors.forename: Sean P
authors.initials: SP
authors.lastname: McAteer
authors.affiliation: Wellcome Trust Centre for Cell Biology, The University of Edinburgh, Edinburgh EH9 3JR, UK. Electronic address: d.tollervey@ed.ac.uk.
authors.forename: David
authors.initials: D
authors.lastname: Tollervey
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK. Electronic address: dgally@ed.ac.uk.
authors.forename: David L
authors.initials: DL
authors.lastname: Gally
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002417:Cattle; D016384:Consensus Sequence; D019453:Escherichia coli O157 / Q000235:genetics / Q000378:metabolism / Q000821:virology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism; D035001:Host Factor 1 Protein / Q000378:metabolism; D008969:Molecular Sequence Data; D009093:Mucus / Q000382:microbiology; D039002:Prophages / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D058727:RNA, Small Untranslated / Q000235:genetics / Q000378:metabolism*; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; C087373:Hfq protein, E coli; D035001:Host Factor 1 Protein; D012333:RNA, Messenger; D058727:RNA, Small Untranslated; D012367:RNA, Viral; D006419:Heme Oxygenase (Decyclizing)