Molecular mechanism of mRNA repression intransby a ProQ-dependent small RNA.
Research into post-transcriptional control of mRNAs by small noncoding RNAs (sRNAs) in the model bacteriaEscherichia coliandSalmonella entericahas mainly focused on sRNAs that associate with the RNA chaperone Hfq. However, the recent discovery of the protein ProQ as a common binding partner that stabilizes a distinct large class of structured sRNAs suggests that additional RNA regulons exist in these organisms. The cellular functions and molecular mechanisms of these new ProQ-dependent sRNAs are largely unknown. Here, we report inSalmonellaTyphimurium the mode-of-action of RaiZ, a ProQ-dependent sRNA that is made from the 3' end of the mRNA encoding ribosome-inactivating protein RaiA. We show that RaiZ is a base-pairing sRNA that represses intransthe mRNA of histone-like protein HU-α. RaiZ forms an RNA duplex with the ribosome-binding site ofhupAmRNA, facilitated by ProQ, to prevent 30S ribosome loading and protein synthesis of HU-α. Similarities and differences between ProQ- and Hfq-mediated regulation will be discussed.
RNA Biology Group, Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany.
Alexandre
0000-0002-9142-7979
A
Smirnov
RNA Biology Group, Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany.
Chuan
C
Wang
RNA Biology Group, Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany.
Lisa L
LL
Drewry
RNA Biology Group, Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany joerg.vogel@uni-wuerzburg.de.|Helmholtz Institute for RNA-based Infection Research (HIRI), Würzburg, Germany.
Jörg
0000-0003-2220-1404
J
Vogel
D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis*; D002352:Carrier Proteins / Q000096:biosynthesis*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000502:physiology*; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism*; D012330:RNA, Double-Stranded / Q000235:genetics / Q000378:metabolism; D058727:RNA, Small Untranslated / Q000235:genetics / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism; D054680:Ribosome Subunits, Small, Bacterial / Q000235:genetics / Q000378:metabolism; D012486:Salmonella typhimurium / Q000235:genetics / Q000378:metabolism*
D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; C099188:HupA protein, bacteria; D026901:Membrane Transport Proteins; D012329:RNA, Bacterial; D012330:RNA, Double-Stranded; D058727:RNA, Small Untranslated; D012269:Ribosomal Proteins
HU‐α; ProQ; RaiZ; small RNA; translation inhibition