RNase Y of Staphylococcus aureus and its role in the activation of virulence genes.
RNase Y of Bacillus subtilis is a key member of the degradosome and important for bulk mRNA turnover. In contrast to B. subtilis, the RNase Y homologue (rny/cvfA) of Staphylococcus aureus is not essential for growth. Here we found that RNase Y plays a major role in virulence gene regulation. Accordingly, rny deletion mutants demonstrated impaired virulence in a murine bacteraemia model. RNase Y is important for the processing and stabilization of the immature transcript of the global virulence regulator system SaePQRS. Moreover, RNase Y is involved in the activation of virulence gene expression at the promoter level. This control is independent of both the virulence regulator agr and the saePQRS processing and may be mediated by small RNAs some of which were shown to be degraded by RNase Y. Besides this regulatory effect, mRNA levels of several operons were significantly increased in the rny mutant and the half-life of one of these operons was shown to be extremely extended. However, the half-life of many mRNA species was not significantly altered. Thus, RNase Y in S. aureus influences mRNA expression in a tightly controlled regulatory manner and is essential for coordinated activation of virulence genes.
Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Germany.
Gabriella
G
Marincola
Tina
T
Schäfer
Juliane
J
Behler
Jörg
J
Bernhardt
Knut
K
Ohlsen
Christiane
C
Goerke
Christiane
C
Wolz
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015964:Gene Expression Regulation, Bacterial; D051379:Mice; D008807:Mice, Inbred BALB C; D012260:Ribonucleases / Q000235:genetics / Q000378:metabolism*; D013203:Staphylococcal Infections / Q000201:enzymology / Q000235:genetics; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics / Q000502:physiology
D001426:Bacterial Proteins; D012260:Ribonucleases