title: A novel Hfq-dependent sRNA that is under FNR control and is synthesized in oxygen limitation in Neisseria meningitidis.
abstract: Small non-coding RNAs (sRNA) are emerging as key elements of post-transcriptional gene regulation in bacteria. The conserved Hfq protein is thought to function as an RNA chaperone and facilitate base-pairing between sRNAs and mRNA targets. In this study we identify a novel sRNA of Neisseria meningitidis through global gene expression studies of regulated transcripts in the Hfq mutant. The synthesis of this sRNA, named AniS, is anaerobically induced through activation of its promoter by the FNR global regulator. Whole-genome expression analyses led to the identification of putative mRNA targets, two of which are predicted to base pair with AniS. We show that Hfq binds the AniS transcript in vitro and is necessary for the downregulation of the identified target mRNAs in vivo. Contrary to many Hfq-dependent sRNA of the Enterobacteriaceae, Hfq promotes decay of AniS in N. meningitidis. Our analysis shows that the AniS regulator is part of the FNR regulon and may be responsible for the downregulation of FNR-repressed genes. Furthermore the presence of similar conserved regulatory sequences in all Neisseria spp. to date suggests that an analogous FNR-regulated sRNA, with a variable 5' sequence, may be ubiquitous to all commensals and pathogens of the Genus.
authors.affiliation: Novartis Vaccines, Microbial Molecular Biology, Via Fiorentina 1, 53100 Siena, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Fantappiè
authors.forename: Francesca
authors.initials: F
authors.lastname: Oriente
authors.forename: Alessandro
authors.initials: A
authors.lastname: Muzzi
authors.forename: Davide
authors.initials: D
authors.lastname: Serruto
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Scarlato
authors.forename: Isabel
authors.initials: I
authors.lastname: Delany
mesh_terms: D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D035001:Host Factor 1 Protein / Q000378:metabolism*; D009345:Neisseria meningitidis / Q000235:genetics* / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D011485:Protein Binding; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000096:biosynthesis*; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D035001:Host Factor 1 Protein; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014157:Transcription Factors; D010100:Oxygen