Riboswitches. Sequestration of a two-component response regulator by a riboswitch-regulated noncoding RNA.

J R Mellin (1) , Mikael Koutero (1) , Daniel Dar (2) , Marie-Anne Nahori (1) , Rotem Sorek (2) , Pascale Cossart (1)

1 UIBC - Interactions Bactéries-Cellules
2 Department of Molecular Genetics

Riboswitches are ligand-binding elements contained within the 5' untranslated regions of bacterial transcripts, which generally regulate expression of downstream open reading frames. Here, we show that in Listeria monocytogenes, a riboswitch that binds vitamin B12 controls expression of a noncoding regulatory RNA, Rli55. Rli55, in turn, controls expression of the eut genes, whose products enable ethanolamine utilization and require B12 as a cofactor. Defects in ethanolamine utilization, or in its regulation by Rli55, significantly attenuate Listeria virulence in mice. Rli55 functions by sequestering the two-component response regulator EutV by means of a EutV-binding site contained within the RNA. Thus, Rli55 is a riboswitch-regulated member of the small group of regulatory RNAs that function by sequestering a protein and reveals a distinctive mechanism of signal integration in bacterial gene regulation.

Mots clés: ethanolamine utilization; antisense rna

Mots clés: enterococcus-faecalis

Domaines: Biologie cellulaire

J R Mellin, Mikael Koutero, Daniel Dar, Marie-Anne Nahori, Rotem Sorek, et al.. Riboswitches. Sequestration of a two-component response regulator by a riboswitch-regulated noncoding RNA.. Science, 2014, 345 (6199), pp.940-3. ⟨10.1126/science.1255083⟩. ⟨pasteur-01120664⟩