Dynamic interactions between the RNA chaperone Hfq, small regulatory RNAs, and mRNAs in live bacterial cells

eLife

Jingyi Fei¹  Emily M Heideman¹  Muhammad S Azam¹  Seongjin Park¹  Wei Liu¹  Matthew A Reyer²  Eric Massé³  Karine Prévost³  Marie-Claude Carrier³ 

[1] Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, United States;Institute for Biophysical Dynamics, The University of Chicago, Chicago, United States;RNA Group, Department of Biochemistry, University of Sherbrooke, Sherbrooke, Canada;

关键词: hfq;    sRNA;    gene regulation;    single-particle tracking;    super-resolution imaging;   

DOI  :  10.7554/eLife.64207

来源: DOAJ

【 摘 要 】

RNA-binding proteins play myriad roles in regulating RNAs and RNA-mediated functions. In bacteria, the RNA chaperone Hfq is an important post-transcriptional gene regulator. Using live-cell super-resolution imaging, we can distinguish Hfq binding to different sizes of cellular RNAs. We demonstrate that under normal growth conditions, Hfq exhibits widespread mRNA-binding activity, with the distal face of Hfq contributing mostly to the mRNA binding in vivo. In addition, sRNAs can either co-occupy Hfq with the mRNA as a ternary complex, or displace the mRNA from Hfq in a binding face-dependent manner, suggesting mechanisms through which sRNAs rapidly access Hfq to induce sRNA-mediated gene regulation. Finally, our data suggest that binding of Hfq to certain mRNAs through its distal face can recruit RNase E to promote turnover of these mRNAs in a sRNA-independent manner, and such regulatory function of Hfq can be decoyed by sRNA competitors that bind strongly at the distal face.

【 授权许可】

Unknown