title: A trans-acting riboswitch controls expression of the virulence regulator PrfA in Listeria monocytogenes.
abstract: Riboswitches are RNA elements acting in cis, controlling expression of their downstream genes through a metabolite-induced alteration of their secondary structure. Here, we demonstrate that two S-adenosylmethionine (SAM) riboswitches, SreA and SreB, can also function in trans and act as noncoding RNAs in Listeria monocytogenes. SreA and SreB control expression of the virulence regulator PrfA by binding to the 5'-untranslated region of its mRNA. Absence of the SAM riboswitches SreA and SreB increases the level of PrfA and virulence gene expression in L. monocytogenes. Thus, the impact of the SAM riboswitches on PrfA expression highlights a link between bacterial virulence and nutrient availability. Together, our results uncover an unexpected role for riboswitches and a distinct class of regulatory noncoding RNAs in bacteria.
authors.affiliation: Department of Molecular Biology, Umeå University, 90187 Umeå, Sweden.
authors.forename: Edmund
authors.initials: E
authors.lastname: Loh
authors.forename: Olivier
authors.initials: O
authors.lastname: Dussurget
authors.forename: Jonas
authors.initials: J
authors.lastname: Gripenland
authors.forename: Karolis
authors.initials: K
authors.lastname: Vaitkevicius
authors.forename: Teresa
authors.initials: T
authors.lastname: Tiensuu
authors.forename: Pierre
authors.initials: P
authors.lastname: Mandin
authors.forename: Francis
authors.initials: F
authors.lastname: Repoila
authors.forename: Carmen
authors.initials: C
authors.lastname: Buchrieser
authors.forename: Pascale
authors.initials: P
authors.lastname: Cossart
authors.forename: Jörgen
authors.initials: J
authors.lastname: Johansson
mesh_terms: D020121:5' Untranslated Regions; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D008089:Listeria monocytogenes / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D008969:Molecular Sequence Data; D010454:Peptide Termination Factors / Q000235:genetics*; D038621:Regulatory Sequences, Ribonucleic Acid; D013696:Temperature; D014774:Virulence
chemical_list: D020121:5' Untranslated Regions; D001426:Bacterial Proteins; D010454:Peptide Termination Factors; C545356:PrfA protein, Listeria monocytogenes; D038621:Regulatory Sequences, Ribonucleic Acid