A Staphylococcus aureus small RNA is required for bacterial virulence and regulates the expression of an immune-evasion molecule.
Staphylococcus aureus, a pathogen responsible for hospital and community-acquired infections, expresses many virulence factors under the control of numerous regulatory systems. Here we show that one of the small pathogenicity island RNAs, named SprD, contributes significantly to causing disease in an animal model of infection. We have identified one of the targets of SprD and our in vivo data demonstrate that SprD negatively regulates the expression of the Sbi immune-evasion molecule, impairing both the adaptive and innate host immune responses. SprD interacts with the 5' part of the sbi mRNA and structural mapping of SprD, its mRNA target, and the 'SprD-mRNA' duplex, in combination with mutational analysis, reveals the molecular details of the regulation. It demonstrates that the accessible SprD central region interacts with the sbi mRNA translational start site. We show by toeprint experiments that SprD prevents translation initiation of sbi mRNA by an antisense mechanism. SprD is a small regulatory RNA required for S. aureus pathogenicity with an identified function, although the mechanism of virulence control by the RNA is yet to be elucidated.
Chabelskaya
Svetlana
S
Université de Rennes I, Inserm U835, Upres EA2311, Biochimie Pharmaceutique, Rennes, France.
Gaillot
Olivier
O
Felden
Brice
B
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D015152:Blotting, Northern; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D005260:Female; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D044404:Genomic Islands / Q000235:genetics*; D006801:Humans; D057131:Immune Evasion; D015151:Immunoblotting; D051379:Mice; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D016372:RNA, Antisense / Q000235:genetics; D012329:RNA, Bacterial / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013203:Staphylococcal Infections / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D013211:Staphylococcus aureus / Q000235:genetics* / Q000472:pathogenicity; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D002352:Carrier Proteins; D016372:RNA, Antisense; D012329:RNA, Bacterial; D012333:RNA, Messenger; D022661:RNA, Untranslated; C112405:Sbi protein, Staphylococcus aureus; D037521:Virulence Factors; D012697:Serine Endopeptidases