Qrrs
Qrrs, short for quorum regulatory RNAs, are a family of small non-coding RNAs that regulate quorum sensing in Vibrio species. They are typically 80–120 nucleotides long and exist as multiple paralogs (for example qrr1, qrr2, qrr3, qrr4) within Vibrio genomes. Expression of Qrrs is driven by the quorum-sensing pathway: at low cell density, the LuxO response regulator remains phosphorylated and activates transcription of qrrs with the help of the sigma-54 factor. Qrr RNAs function with the RNA chaperone Hfq to regulate target mRNAs by base-pairing, often leading to decreased translation and/or accelerated mRNA decay.
Key targets of Qrrs include master regulators such as hapR in Vibrio cholerae and luxR in other
At high cell density, autoinducers trigger a phosphorelay that deactivates LuxO, leading to reduced qrr transcription
Evolution and diversity: the number and exact targets of qrr genes vary among Vibrio species, but the