Eric Massé

Although small regulatory RNAs are numerous (~100 sRNAs in E. coli) and play significant functions in the physiology of living organisms, their mechanisms of action remain largely unknown. sRNAs are usually shorter than 300 nucleotides, non-coding, and found in both eukaryotic and prokaryotic organisms. Because they can directly regulate virulence factors and antibiotic resistance in bacterial pathogens, sRNAs are extremely potent modulators of gene expression. Our recent work with E. coli has revealed unique features of sRNAs; (1) a single sRNA can rapidly silence mRNAs by recruiting the RNA chaperone Hfq to block translation; (2) sRNAs can recruit ribonucleases such as RNase E to induce sRNA-mediated mRNA decay; (3) sponge RNAs can regulate sRNA functions and dramatically change response to stress.