The Bacterial Toxin RelE Displays Codon-Specific Cleavage of mRNAs in the Ribosomal A Site

نویسندگان

  • Kim Pedersen
  • Andrey V. Zavialov
  • Michael Yu. Pavlov
  • Johan Elf
  • Kenn Gerdes
  • Måns Ehrenberg
چکیده

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.

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عنوان ژورنال:
  • Cell

دوره 112  شماره 

صفحات  -

تاریخ انتشار 2003