Profiling of myristoylation in Toxoplasma gondii reveals an N-myristoylated protein important for host cell penetration

Abstract

N-myristoylation is a ubiquitous class of protein lipidation across eukaryotes and N-myristoyl transferase (NMT) has been proposed as an attractive drug target in several pathogens. Myristoylation often primes for subsequent palmitoylation and stable membrane attachment, however, growing evidence suggests additional regulatory roles for myristoylation on proteins. Here we describe the myristoylated proteome of Toxoplasma gondii using chemoproteomic methods and show that a small-molecule NMT inhibitor developed against related Plasmodium spp. is also functional in Toxoplasma. We identify myristoylation on a transmembrane protein, the microneme protein 7 (MIC7), which enters the secretory pathway in an unconventional fashion with the myristoylated N-terminus facing the lumen of the micronemes. MIC7 and its myristoylation play a crucial role in the initial steps of invasion, likely during the interaction with and penetration of the host cell. Myristoylation of secreted eukaryotic proteins represents a substantial expansion of the functional repertoire of this co-translational modification.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 5, 6 and 7. Source data for mass spectrometry proteomics results can be found in Supplementary files 1-4. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE (Perez-Riverol et al., 2019) partner repository with the dataset identifier PXD019677.

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Malgorzata Broncel

    Signalling in Apicomplexan Parasites Lab, The Francis Crick Institute, London, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2991-3500
  2. Caia Dominicus

    Signalling in Apicomplexan Parasites Lab, The Francis Crick Institute, London, United Kingdom
    Competing interests
    No competing interests declared.
  3. Luis Vigetti

    Institute for Advanced Biosciences, Université Grenoble Alpes, Grenoble, France
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9733-2770
  4. Stephanie D Nofal

    Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1415-3369
  5. Edward J Bartlett

    Department of Chemistry, Imperial College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  6. Bastien Touquet

    Team Membrane and Cell Dynamics of Host Parasite Interactions, Université Grenoble Alpes, Grenoble, France
    Competing interests
    No competing interests declared.
  7. Alex Hunt

    Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7431-7156
  8. Bethan Alexandra Wallbank

    Signalling in Apicomplexan Parasites Lab, The Francis Crick Institute, London, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6432-2135
  9. Stefania Federico

    Peptide Synthesis STP, The Francis Crick Institute, London, United Kingdom
    Competing interests
    No competing interests declared.
  10. Stephen Matthews

    Department of Life Sciences, Imperial College London, London, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0676-0927
  11. Joanna Claire Young

    Signalling in Apicomplexan Parasites Lab, The Francis Crick Institute, London, United Kingdom
    Competing interests
    No competing interests declared.
  12. Edward W Tate

    Department of Chemistry, Imperial College London, London, United Kingdom
    Competing interests
    Edward W Tate, EWT is a founder, shareholder and Director of Myricx Pharma Ltd.
  13. Isabelle Tardieux

    Team Membrane and Cell Dynamics of Host Parasite Interactions, Université Grenoble Alpes, Grenoble, France
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5677-7463
  14. Moritz Treeck

    Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
    For correspondence
    moritz.treeck@crick.ac.uk
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9727-6657

Funding

Francis Crick Institute (FC001189)

  • Malgorzata Broncel
  • Caia Dominicus
  • Stephanie D Nofal
  • Alex Hunt
  • Bethan Alexandra Wallbank
  • Joanna Claire Young
  • Moritz Treeck

NIH Office of the Director (R01AI123457)

  • Malgorzata Broncel
  • Caia Dominicus
  • Moritz Treeck

Leverhulme Trust (RPG-2018-107)

  • Stephen Matthews

Cancer Research UK (C29637/A20183)

  • Edward J Bartlett
  • Edward W Tate

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

Reviewing Editor

  1. Dominique Soldati-Favre, University of Geneva, Switzerland

Version history

  1. Received: April 14, 2020
  2. Accepted: June 27, 2020
  3. Accepted Manuscript published: July 3, 2020 (version 1)
  4. Version of Record published: July 21, 2020 (version 2)

Copyright

© 2020, Broncel 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.

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  1. Malgorzata Broncel
  2. Caia Dominicus
  3. Luis Vigetti
  4. Stephanie D Nofal
  5. Edward J Bartlett
  6. Bastien Touquet
  7. Alex Hunt
  8. Bethan Alexandra Wallbank
  9. Stefania Federico
  10. Stephen Matthews
  11. Joanna Claire Young
  12. Edward W Tate
  13. Isabelle Tardieux
  14. Moritz Treeck
(2020)
Profiling of myristoylation in Toxoplasma gondii reveals an N-myristoylated protein important for host cell penetration
eLife 9:e57861.
https://doi.org/10.7554/eLife.57861

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