In vivo 3'-to-5' exoribonuclease targetomes of
| Autor: | Anne-Laure, Lécrivain, Anaïs, Le Rhun, Thibaud T, Renault, Rina, Ahmed-Begrich, Karin, Hahnke, Emmanuelle, Charpentier |
|---|---|
| Rok vydání: | 2018 |
| Předmět: | |
| Zdroj: | Proceedings of the National Academy of Sciences of the United States of America |
| ISSN: | 1091-6490 |
| Popis: | Significance To cope with harsh environments and cause infection, bacteria need to constantly adjust gene expression. Ribonucleases (RNases) control the abundance of regulatory and protein-coding RNA through degradation and maturation. The current characterization of 3′-to-5′ exoribonucleases (exoRNases), processing RNAs from their 3′ end, is solely based on the description of a limited number of targets processed by these RNases. Here, we characterized bacterial 3′-to-5′ exoRNase targetomes. We show that YhaM, polynucleotide phosphorylase (PNPase), and RNase R have exoribonucleolytic activities in the human pathogen Streptococcus pyogenes. We demonstrate that PNPase is the main 3′-to-5′ exoRNase participating in RNA decay, we show that RNase R has a limited processing activity, and we describe an intriguing RNA processing behavior for YhaM. mRNA decay plays an essential role in the control of gene expression in bacteria. Exoribonucleases (exoRNases), which trim transcripts starting from the 5′ or 3′ end, are particularly important to fully degrade unwanted transcripts and renew the pool of nucleotides available in the cell. While recent techniques have allowed genome-wide identification of ribonuclease (RNase) targets in bacteria in vivo, none of the 3′-to-5′ exoRNase targetomes (i.e., global processing sites) have been studied so far. Here, we report the targetomes of YhaM, polynucleotide phosphorylase (PNPase), and RNase R of the human pathogen Streptococcus pyogenes. We determined that YhaM is an unspecific enzyme that trims a few nucleotides and targets the majority of transcript ends, generated either by transcription termination or by endonucleolytic activity. The molecular determinants for YhaM-limited processivity are yet to be deciphered. We showed that PNPase clears the cell from mRNA decay fragments produced by endoribonucleases (endoRNases) and is the major 3′-to-5′ exoRNase for RNA turnover in S. pyogenes. In particular, PNPase is responsible for the degradation of regulatory elements from 5′ untranslated regions. However, we observed little RNase R activity in standard culture conditions. Overall, our study sheds light on the very distinct features of S. pyogenes 3′-to-5′ exoRNases. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|