Cargando…

Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli

BACKGROUND: Polynucleotide phosphorylase (PNPase, encoded by pnp) is generally thought of as an enzyme dedicated to RNA metabolism. The pleiotropic effects of PNPase deficiency is imputed to altered processing and turnover of mRNAs and small RNAs, which in turn leads to aberrant gene expression. How...

Descripción completa

Detalles Bibliográficos
Autores principales: Carzaniga, Thomas, Sbarufatti, Giulia, Briani, Federica, Dehò, Gianni
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5379764/
https://www.ncbi.nlm.nih.gov/pubmed/28376742
http://dx.doi.org/10.1186/s12866-017-0980-z
_version_ 1782519673505447936
author Carzaniga, Thomas
Sbarufatti, Giulia
Briani, Federica
Dehò, Gianni
author_facet Carzaniga, Thomas
Sbarufatti, Giulia
Briani, Federica
Dehò, Gianni
author_sort Carzaniga, Thomas
collection PubMed
description BACKGROUND: Polynucleotide phosphorylase (PNPase, encoded by pnp) is generally thought of as an enzyme dedicated to RNA metabolism. The pleiotropic effects of PNPase deficiency is imputed to altered processing and turnover of mRNAs and small RNAs, which in turn leads to aberrant gene expression. However, it has long since been known that this enzyme may also catalyze template-independent polymerization of dNDPs into ssDNA and the reverse phosphorolytic reaction. Recently, PNPase has been implicated in DNA recombination, repair, mutagenesis and resistance to genotoxic agents in diverse bacterial species, raising the possibility that PNPase may directly, rather than through control of gene expression, participate in these processes. RESULTS: In this work we present evidence that in Escherichia coli PNPase enhances both homologous recombination upon P1 transduction and error prone DNA repair of double strand breaks induced by zeocin, a radiomimetic agent. Homologous recombination does not require PNPase phosphorolytic activity and is modulated by its RNA binding domains whereas error prone DNA repair of zeocin-induced DNA damage is dependent on PNPase catalytic activity and cannot be suppressed by overexpression of RNase II, the other major enzyme (encoded by rnb) implicated in exonucleolytic RNA degradation. Moreover, E. coli pnp mutants are more sensitive than the wild type to zeocin. This phenotype depends on PNPase phosphorolytic activity and is suppressed by rnb, thus suggesting that zeocin detoxification may largely depend on RNA turnover. CONCLUSIONS: Our data suggest that PNPase may participate both directly and indirectly through regulation of gene expression to several aspects of DNA metabolism such as recombination, DNA repair and resistance to genotoxic agents.
format Online
Article
Text
id pubmed-5379764
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-53797642017-04-10 Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli Carzaniga, Thomas Sbarufatti, Giulia Briani, Federica Dehò, Gianni BMC Microbiol Research Article BACKGROUND: Polynucleotide phosphorylase (PNPase, encoded by pnp) is generally thought of as an enzyme dedicated to RNA metabolism. The pleiotropic effects of PNPase deficiency is imputed to altered processing and turnover of mRNAs and small RNAs, which in turn leads to aberrant gene expression. However, it has long since been known that this enzyme may also catalyze template-independent polymerization of dNDPs into ssDNA and the reverse phosphorolytic reaction. Recently, PNPase has been implicated in DNA recombination, repair, mutagenesis and resistance to genotoxic agents in diverse bacterial species, raising the possibility that PNPase may directly, rather than through control of gene expression, participate in these processes. RESULTS: In this work we present evidence that in Escherichia coli PNPase enhances both homologous recombination upon P1 transduction and error prone DNA repair of double strand breaks induced by zeocin, a radiomimetic agent. Homologous recombination does not require PNPase phosphorolytic activity and is modulated by its RNA binding domains whereas error prone DNA repair of zeocin-induced DNA damage is dependent on PNPase catalytic activity and cannot be suppressed by overexpression of RNase II, the other major enzyme (encoded by rnb) implicated in exonucleolytic RNA degradation. Moreover, E. coli pnp mutants are more sensitive than the wild type to zeocin. This phenotype depends on PNPase phosphorolytic activity and is suppressed by rnb, thus suggesting that zeocin detoxification may largely depend on RNA turnover. CONCLUSIONS: Our data suggest that PNPase may participate both directly and indirectly through regulation of gene expression to several aspects of DNA metabolism such as recombination, DNA repair and resistance to genotoxic agents. BioMed Central 2017-04-04 /pmc/articles/PMC5379764/ /pubmed/28376742 http://dx.doi.org/10.1186/s12866-017-0980-z Text en © The Author(s). 2017 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research Article
Carzaniga, Thomas
Sbarufatti, Giulia
Briani, Federica
Dehò, Gianni
Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli
title Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli
title_full Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli
title_fullStr Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli
title_full_unstemmed Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli
title_short Polynucleotide phosphorylase is implicated in homologous recombination and DNA repair in Escherichia coli
title_sort polynucleotide phosphorylase is implicated in homologous recombination and dna repair in escherichia coli
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5379764/
https://www.ncbi.nlm.nih.gov/pubmed/28376742
http://dx.doi.org/10.1186/s12866-017-0980-z
work_keys_str_mv AT carzanigathomas polynucleotidephosphorylaseisimplicatedinhomologousrecombinationanddnarepairinescherichiacoli
AT sbarufattigiulia polynucleotidephosphorylaseisimplicatedinhomologousrecombinationanddnarepairinescherichiacoli
AT brianifederica polynucleotidephosphorylaseisimplicatedinhomologousrecombinationanddnarepairinescherichiacoli
AT dehogianni polynucleotidephosphorylaseisimplicatedinhomologousrecombinationanddnarepairinescherichiacoli