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Published on: February 21, 2019
Vacuolar protein sorting mechanisms in apicomplexan parasites
Elena Jimenez-Ruiz1, Juliette Morlon-Guyot2, Wassim Daher2
1Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, Glasgow, Lanarkshire, United Kingdom.
Apicomplexan parasites like Toxoplasma gondii utilize a limited set of vacuolar protein sorting (VPS) factors. This review explores their roles in protein trafficking and proposes a model for membrane and micronemal protein recycling.
Area of Science:
- Parasitology
- Cell Biology
- Molecular Biology
Background:
- Apicomplexa are significant pathogens with complex endomembrane systems.
- Secretory organelles (rhoptries, micronemes, dense granules) release proteins crucial for host cell invasion.
- Despite complexity, apicomplexans possess a reduced set of vacuolar protein sorting (VPS) factors compared to other eukaryotes.
Purpose of the Study:
- To review current knowledge on trafficking complexes in Toxoplasma gondii.
- To highlight recent studies on VPS protein complexes.
- To propose a novel model for parasite membrane and micronemal protein recycling.
Main Methods:
- Literature review of studies on protein trafficking in T. gondii.
- Focus on complexes involving vacuolar protein sorting (VPS) proteins.
- Presentation of a hypothetical model for protein recycling.
Main Results:
- T. gondii and related parasites have lost several VPS homologues found in other eukaryotes.
- A core set of trafficking factors is utilized for protein sorting.
- Recent studies elucidate the function of specific VPS protein complexes.
Conclusions:
- The limited set of VPS factors in apicomplexans is sufficient for essential protein trafficking.
- A novel model suggests recycling mechanisms for parasite membrane and micronemal proteins.
- Further research is needed to validate the proposed recycling model.
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