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Preparing Lamellae from Vitreous Biological Samples Using a Dual-Beam Scanning Electron Microscope for Cryo-Electron Tomography
Published on: August 5, 2021
Structural dissection of apicomplexan gliding motility
Pankti Vaishnav1, Josie L Ferreira1
1Institute of Structural and Molecular Biology, SMB, Darwin Building, University, College London, Gower Street, London WC1E 6BT, UK.
Current Opinion in Structural Biology
|July 17, 2026
Summary
Apicomplexan parasites use unstable actin filaments for gliding motility. Spatial mechanisms, like a molecular conveyor belt, ensure efficient movement despite actin instability, crucial for parasite transmission.
Area of Science:
- Parasitology
- Cell Biology
- Biophysics
Background:
- Apicomplexan parasites cause diseases like malaria, toxoplasmosis, and cryptosporidiosis.
- These parasites rely on gliding motility for host cell invasion.
- The mechanism of efficient gliding using unstable actin filaments presents a paradox.
Purpose of the Study:
- To resolve the paradox of how apicomplexan parasites achieve efficient gliding motility.
- To elucidate the spatial mechanisms compensating for actin filament instability.
Main Methods:
- Cryo-electron microscopy (cryo-EM) was used to determine structural details.
- Analysis focused on actin isoforms, connectors, and nucleation sites.
Main Results:
- A spatial mechanism involving a molecular conveyor belt was revealed.
- Actin filaments are nucleated apically, channeled, guided, and recycled posteriorly.
- Continuous and rapid actin turnover prevents accumulation and enables motility.
Conclusions:
- Spatial organization and rapid turnover of actin filaments are key to apicomplexan gliding motility.
- This mechanism overcomes the inherent instability of eukaryotic actin.
- Understanding these processes is critical for targeting parasite transmission.
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