Abstract
A hierarchical control of fimbrial gene expression limits laboratory grown cultures of Salmonella enterica serovar typhimurium (S. typhimurium) to the production of type I fimbriae encoded by the fimAICDHF operon. Here we show that an unlikely culprit, namely the 5′-untranslated region (5′-UTR) of a messenger (m)RNA, coordinated the regulation. Binding of CsrA to the 5′-UTR of the pefACDEF transcript was required for expression of plasmid-encoded fimbriae. The 5′-UTR of the fimAICDHF transcript cooperated with two small untranslated RNAs, termed CsrB and CsrC, in antagonizing the activity of the RNA binding protein CsrA. Through this post-transcriptional mechanism, the 5′-UTR of the fimAICDHF transcript prevented production of PefA, the major structural subunit of plasmid-encoded fimbriae. This regulatory mechanism limits the costly expression of plasmid-encoded fimbriae to host environments in a mouse model. Collectively, our data suggest that the 5′-UTR of an mRNA coordinates a hierarchical control of fimbrial gene expression in S. typhimurium.
Original language | English (US) |
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Pages (from-to) | 2872-2883 |
Number of pages | 12 |
Journal | EMBO Journal |
Volume | 32 |
Issue number | 21 |
DOIs | |
State | Published - Oct 30 2013 |
Keywords
- fimbriae
- gene regulation
- Salmonella
ASJC Scopus subject areas
- Molecular Biology
- Biochemistry, Genetics and Molecular Biology(all)
- Immunology and Microbiology(all)
- Neuroscience(all)