Toxoplasma gondii F-actin forms an extensive filamentous network required for material exchange and parasite maturation
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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