Toxoplasma gondii F-actin forms an extensive filamentous network required for material exchange and parasite maturation
- University of Glasgow, United Kingdom
- Cancer Research UK Beatson Institute, United Kingdom
- University of Vermont, United States
Abstract
Apicomplexan actin is important during the parasite's life cycle. Its polymerization kinetics are unusual, permitting only short, unstable F-actin filaments. It has not been possible to study actin in vivo and so its physiological roles have remained obscure, leading to models distinct from conventional actin behaviour. Here a modified version of the commercially available Actin-Chromobody® was tested as a novel tool for visualising F-actin dynamics in Toxoplasma gondii. Cb labels filamentous actin structures within the parasite cytosol and labels an extensive F-actin network that connects parasites within the parasitophorous vacuole and allows vesicles to be exchanged between parasites. In the absence of actin, parasites lack a residual body and inter-parasite connections and grow in an asynchronous and disorganized manner. Collectively, these data identify new roles for actin in the intracellular phase of the parasites lytic cycle and provide a robust new tool for imaging parasitic F-actin dynamics.
Article and author information
Author details
Funding
Wellcome (087582/Z/08/Z)
- Markus Meissner
H2020 European Research Council (ERC-2012-StG 309255-EndoTox)
- Markus Meissner
Wellcome (WT103972AIA)
- Clare Harding
National Institute for Health Research (AI121885)
- Aoife Heaslip
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Periz 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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Further reading
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A parasite called Toxoplasma gondii builds a scaffold inside human and other animal cells to help it multiply and cause disease.
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