A plant-like mechanism coupling m6A reading to polyadenylation safeguards transcriptome integrity and developmental gene partitioning in Toxoplasma

  1. Dayana C Farhat
  2. Matthew W Bowler
  3. Guillaume Communie
  4. Dominique Pontier
  5. Lucid Belmudes
  6. Caroline Mas
  7. Charlotte Corrao
  8. Yohann Couté
  9. Alexandre Bougdour
  10. Thierry Lagrange
  11. Mohamed-ali Hakimi  Is a corresponding author
  12. Christopher Swale  Is a corresponding author
  1. Université Grenoble Alpes, France
  2. European Molecular Biology Laboratory, France
  3. Institut Laue-Langevin, France
  4. CNRS, France

Abstract

Correct 3'end processing of mRNAs is one of the regulatory cornerstones of gene expression. In a parasite that must adapt to the regulatory requirements of its multi-host life style, there is a need to adopt additional means to partition the distinct transcriptional signatures of the closely and tandemly-arranged stage specific genes. In this study, we report our findings in T. gondii of an m6A-dependent 3'end polyadenylation serving as a transcriptional barrier at these loci. We identify the core polyadenylation complex within T. gondii and establish CPSF4 as a reader for m6A-modified mRNAs, via a YTH domain within its C-terminus, a feature which is shared with plants. We bring evidence of the specificity of this interaction both biochemically, and by determining the crystal structure at high resolution of the T. gondii CPSF4-YTH in complex with an m6A modified RNA. We show that the loss of m6A, both at the level of its deposition or its recognition was associated with an increase in aberrantly elongated chimeric mRNAs emanating from impaired transcriptional termination, a phenotype previously noticed in the plant model Arabidopsis thaliana. Nanopore direct RNA sequencing shows the occurrence of transcriptional read-through breaching into downstream repressed stage-specific genes, in the absence of either CPSF4 or the m6A RNA methylase components in both T. gondii and A. thaliana. Taken together, our results shed light on an essential regulatory mechanism coupling the pathways of m6A metabolism directly to the cleavage and polyadenylation processes, one that interestingly seem to serve, in both T. gondii and A. thaliana, as a guardian against aberrant transcriptional read-throughs.

Data availability

The Nanopore RNAseq data have been deposited in NCBI's SRA data PRJNA705300. The MS proteomics data have been deposited to the ProteomeXchange Consortium through the PRIDE partner repository with the dataset identifier PXD024326. Sequencing data have been deposited in GEO under accession code GSE168155:

The following data sets were generated

Article and author information

Author details

  1. Dayana C Farhat

    Team Host-pathogen interactions and Immunity to Infection, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  2. Matthew W Bowler

    European Molecular Biology Laboratory, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0465-3351
  3. Guillaume Communie

    Institut Laue-Langevin, Institut Laue-Langevin, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Dominique Pontier

    UMR5096, CNRS, Perpignan, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Lucid Belmudes

    BIG-BGE, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Caroline Mas

    Integrated Structural Biology Grenoble (ISBG), Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Charlotte Corrao

    Team Host-pathogen interactions and Immunity to Infection, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  8. Yohann Couté

    Institut de Biosciences et Biotechnologies de Grenoble, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3896-6196
  9. Alexandre Bougdour

    Institut de Biosciences et Biotechnologies de Grenoble, Université Grenoble Alpes, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5895-0020
  10. Thierry Lagrange

    UMR5096, CNRS, Grenoble, France
    Competing interests
    The authors declare that no competing interests exist.
  11. Mohamed-ali Hakimi

    Team Host-pathogen interactions and Immunity to Infection, Université Grenoble Alpes, Grenoble, France
    For correspondence
    mohamed-ali.hakimi@inserm.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2547-8233
  12. Christopher Swale

    Team Host-pathogen interactions and Immunity to Infection, Université Grenoble Alpes, Grenoble, France
    For correspondence
    christopher.swale@univ-grenoble-alpes.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9739-7774

Funding

Agence Nationale de la Recherche (Laboratoire d'Excellence (LabEx) ParaFrap [ANR-11-LABX-0024])

  • Dayana C Farhat
  • Mohamed-ali Hakimi
  • Christopher Swale

Agence Nationale de la Recherche (Project HostQuest,ANR-18-CE15-0023)

  • Charlotte Corrao
  • Alexandre Bougdour
  • Mohamed-ali Hakimi
  • Christopher Swale

European Research Council (ERC Consolidator Grant N{degree sign}614880 Hosting TOXO)

  • Mohamed-ali Hakimi

Fondation pour la Recherche Médicale (FRM FDT201904008364)

  • Dayana C Farhat
  • Mohamed-ali Hakimi

Agence Nationale de la Recherche (Proteomics French Infrastructure,Infrastructure Nationale en Biologie et Santé,ANR-10-INBS-08)

  • Lucid Belmudes
  • Yohann Couté

Agence Nationale de la Recherche (Laboratoires d'Excellences (LABEX) TULIP (ANR-10-LABX-41)")

  • Dominique Pontier
  • Thierry Lagrange

Agence Nationale de la Recherche (École Universitaire de Recherche (EUR)" TULIP-GS (ANR-18-EURE-0019)")

  • Dominique Pontier
  • Thierry Lagrange

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2021, Farhat et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 2,268
    views
  • 323
    downloads
  • 20
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Dayana C Farhat
  2. Matthew W Bowler
  3. Guillaume Communie
  4. Dominique Pontier
  5. Lucid Belmudes
  6. Caroline Mas
  7. Charlotte Corrao
  8. Yohann Couté
  9. Alexandre Bougdour
  10. Thierry Lagrange
  11. Mohamed-ali Hakimi
  12. Christopher Swale
(2021)
A plant-like mechanism coupling m6A reading to polyadenylation safeguards transcriptome integrity and developmental gene partitioning in Toxoplasma
eLife 10:e68312.
https://doi.org/10.7554/eLife.68312

Share this article

https://doi.org/10.7554/eLife.68312

Further reading

    1. Microbiology and Infectious Disease
    Han Kang Tee, Simon Crouzet ... Caroline Tapparel
    Research Article Updated

    Because of high mutation rates, viruses constantly adapt to new environments. When propagated in cell lines, certain viruses acquire positively charged amino acids on their surface proteins, enabling them to utilize negatively charged heparan sulfate (HS) as an attachment receptor. In this study, we used enterovirus A71 (EV-A71) as the model and demonstrated that, unlike the parental MP4 variant, the cell-adapted strong HS-binder MP4-97R/167 G does not require acidification for uncoating and releases its genome in the neutral or weakly acidic environment of early endosomes. We experimentally confirmed that this pH-independent entry is not associated with the use of HS as an attachment receptor but rather with compromised capsid stability. We then extended these findings to another HS-dependent strain. In summary, our data indicate that the acquisition of capsid mutations conferring affinity for HS comes together with decreased capsid stability and allows EV-A71 to enter the cell via a pH-independent pathway. This pH-independent entry mechanism boosts viral replication in cell lines but may prove deleterious in vivo, especially for enteric viruses crossing the acidic gastric environment before reaching their primary replication site, the intestine. Our study thus provides new insight into the mechanisms underlying the in vivo attenuation of HS-binding EV-A71 strains. Not only are these viruses hindered in tissues rich in HS due to viral trapping, as generally accepted, but our research reveals that their diminished capsid stability further contributes to attenuation in vivo. This underscores the complex relationship between HS-binding, capsid stability, and viral fitness, where increased replication in cell lines coincides with attenuation in harsh in vivo environments like the gastrointestinal tract.

    1. Genetics and Genomics
    2. Microbiology and Infectious Disease
    Louna Fruchard, Anamaria Babosan ... Zeynep Baharoglu
    Research Article

    Tgt is the enzyme modifying the guanine (G) in tRNAs with GUN anticodon to queuosine (Q). tgt is required for optimal growth of Vibrio cholerae in the presence of sub-lethal aminoglycoside concentrations. We further explored here the role of the Q34 in the efficiency of codon decoding upon tobramycin exposure. We characterized its impact on the overall bacterial proteome, and elucidated the molecular mechanisms underlying the effects of Q34 modification in antibiotic translational stress response. Using molecular reporters, we showed that Q34 impacts the efficiency of decoding at tyrosine TAT and TAC codons. Proteomics analyses revealed that the anti-SoxR factor RsxA is better translated in the absence of tgt. RsxA displays a codon bias toward tyrosine TAT and overabundance of RsxA leads to decreased expression of genes belonging to SoxR oxidative stress regulon. We also identified conditions that regulate tgt expression. We propose that regulation of Q34 modification in response to environmental cues leads to translational reprogramming of transcripts bearing a biased tyrosine codon usage. In silico analysis further identified candidate genes which could be subject to such translational regulation, among which DNA repair factors. Such transcripts, fitting the definition of modification tunable transcripts, are central in the bacterial response to antibiotics.