Differential requirements for cyclase-associated protein (CAP) in actin-dependent processes of Toxoplasma gondii

  1. Alex Hunt
  2. Matthew Robert Geoffrey Russell
  3. Jeanette Wagener
  4. Robyn Kent
  5. Romain Carmeille
  6. Christopher J Peddie
  7. Lucy Collinson
  8. Aoife Heaslip
  9. Gary E Ward
  10. Moritz Treeck  Is a corresponding author
  1. The Francis Crick Institute, United Kingdom
  2. University of Vermont, United States
  3. University of Connecticut, United States

Abstract

Toxoplasma gondii contains a limited subset of actin binding proteins. Here we show that the putative actin regulator cyclase-associated protein (CAP) is present in two different isoforms and its deletion leads to significant defects in some but not all actin dependent processes. We observe defects in cell-cell communication, daughter cell orientation and the juxtanuclear accumulation of actin, but only modest defects in synchronicity of division and no defect in the replication of the apicoplast. 3D electron microscopy reveals that loss of CAP results in a defect in formation of a normal central residual body, but parasites remain connected within the vacuole. This dissociates synchronicity of division and parasite rosetting and reveals that establishment and maintenance of the residual body may be more complex than previously thought. These results highlight the different spatial requirements for F-actin regulation in Toxoplasma which appear to be achieved by partially overlapping functions of actin regulators.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 4, 5, 6, 8 and 10. Data Availability: Raw data for FIB SEM supporting movies will be uploaded to EMPIAR. Raw data for FIB SEM supporting movies have been deposited to EMPIAR.

Article and author information

Author details

  1. Alex Hunt

    Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7431-7156
  2. Matthew Robert Geoffrey Russell

    Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4608-7669
  3. Jeanette Wagener

    Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7227-4348
  4. Robyn Kent

    Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Romain Carmeille

    Department of Molecular and Cell Biology, University of Connecticut, Storrs, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Christopher J Peddie

    Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Lucy Collinson

    Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Aoife Heaslip

    Department of Molecular and Cell Biology, University of Connecticut, Storrs, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Gary E Ward

    Deaprtment of Microbiology and Molecular Genetics, University of Vermont, Burlington, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Moritz Treeck

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

Funding

Francis Crick Institute (FC001189)

  • Lucy Collinson

NIH Office of the Director (AI121885)

  • Romain Carmeille
  • Aoife Heaslip

NIH Office of the Director (AI139201)

  • Robyn Kent
  • Gary E Ward

Francis Crick Institute (FC001999)

  • Matthew Robert Geoffrey Russell
  • Christopher J Peddie
  • Lucy Collinson

NIH Office of the Director (AI137767)

  • Robyn Kent
  • Gary E Ward

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

Ethics

Animal experimentation: All experiments were performed in accordance with UK Home Office regulations (PPL 80/2616) and approved by the ethical review panel at the Francis Crick Institute.

Reviewing Editor

  1. Friedrich Frischknecht, Medical School Heidelberg, Germany

Publication history

  1. Received: July 30, 2019
  2. Accepted: September 26, 2019
  3. Accepted Manuscript published: October 2, 2019 (version 1)
  4. Version of Record published: October 9, 2019 (version 2)

Copyright

© 2019, Hunt 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. Alex Hunt
  2. Matthew Robert Geoffrey Russell
  3. Jeanette Wagener
  4. Robyn Kent
  5. Romain Carmeille
  6. Christopher J Peddie
  7. Lucy Collinson
  8. Aoife Heaslip
  9. Gary E Ward
  10. Moritz Treeck
(2019)
Differential requirements for cyclase-associated protein (CAP) in actin-dependent processes of Toxoplasma gondii
eLife 8:e50598.
https://doi.org/10.7554/eLife.50598

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