Differential requirements for cyclase-associated protein (CAP) in actin-dependent processes of Toxoplasma gondii
- The Francis Crick Institute, United Kingdom
- University of Vermont, United States
- 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
Matthew Robert Geoffrey Russell
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.
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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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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