The bacterial toxin RelE displays codon-specific cleavage of mRNAs in the ribosomal A site.
The Escherichia coli relBE operon encodes a toxin-antitoxin pair, RelE-RelB. RelB can reverse inhibition of protein synthesis by RelE in vivo. We have found that although RelE does not degrade free RNA, it cleaves mRNA in the ribosomal A site with high codon specificity. Among stop codons UAG is cleaved with fast, UAA intermediate and UGA slow rate, while UCG and CAG are cleaved most rapidly among sense codons. We suggest that inhibition of protein synthesis by RelE is reversed with the help of tmRNA, and that RelE plays a regulatory role in bacteria during adaptation to poor growth conditions.
Pedersen
Kim
K
Department of Biochemistry and Molecular Biology, OU, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
Zavialov
Andrey V
AV
Pavlov
Michael Yu
MY
Elf
Johan
J
Gerdes
Kenn
K
Ehrenberg
Måns
M
D001427:Bacterial Toxins / Q000378:metabolism*; D002384:Catalysis; D003062:Codon; D018388:Codon, Terminator; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000378:metabolism*; D005798:Genes, Bacterial / Q000235:genetics; D066298:In Vitro Techniques; D008957:Models, Genetic; D009876:Operon; D010452:Peptide Biosynthesis; D014176:Protein Biosynthesis; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000378:metabolism*; D013489:Suppression, Genetic; D013997:Time Factors
D001427:Bacterial Toxins; D003062:Codon; D018388:Codon, Terminator; D029968:Escherichia coli Proteins; D011500:Protein Synthesis Inhibitors; D012333:RNA, Messenger; C465566:RelE protein, E coli; D012269:Ribosomal Proteins; C016700:ribosomal protein L7-L12