Multiple small RNAs act additively to integrate sensory information and control quorum sensing in Vibrio harveyi.

TitleMultiple small RNAs act additively to integrate sensory information and control quorum sensing in Vibrio harveyi.
Publication TypeJournal Article
Year of Publication2007
AuthorsTu, KC, Bassler, BL
JournalGenes Dev
Volume21
Issue2
Pagination221-33
Date Published2007 Jan 15
ISSN0890-9369
KeywordsBase Sequence, Colony Count, Microbial, Gene Expression Regulation, Bacterial, Molecular Sequence Data, Nucleic Acid Conformation, Quorum Sensing, Repressor Proteins, RNA, Bacterial, Sequence Alignment, Trans-Activators, Vibrio
Abstract

<p>Quorum sensing is a cell-cell communication mechanism that bacteria use to collectively regulate gene expression and, at a higher level, to coordinate group behavior. In the bioluminescent marine bacterium Vibrio harveyi, sensory information from three independent quorum-sensing systems converges on the shared response regulator LuxO. When LuxO is phosphorylated, it activates the expression of a putative repressor that destabilizes the mRNA encoding the master quorum-sensing transcriptional regulator LuxR. In the closely related species Vibrio cholerae, this repressor was revealed to be the RNA chaperone Hfq together with four small regulatory RNAs (sRNAs) called Qrr1-4 (quorum regulatory RNA). Here, we identify five Qrr sRNAs that control quorum sensing in V. harveyi. Mutational analysis reveals that only four of the five Qrrs are required for destabilization of the luxR mRNA. Surprisingly, unlike in V. cholerae where the sRNAs act redundantly, in V. harveyi, the Qrr sRNAs function additively to control quorum sensing. This latter mechanism produces a gradient of LuxR that, in turn, enables differential regulation of quorum-sensing target genes. Other regulators appear to be involved in control of V. harveyi qrr expression, allowing the integration of additional sensory information into the regulation of quorum-sensing gene expression.</p>

DOI10.1101/gad.1502407
Alternate JournalGenes Dev.
PubMed ID17234887
PubMed Central IDPMC1770904
Grant ListR01 GM 065859 / GM / NIGMS NIH HHS / United States