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Updated: May 16, 2026
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Applying Live Cell Imaging and Cryo-Electron Tomography to Resolve Spatiotemporal Features of the Legionella pneumophila Dot/Icm Secretion System
Published on: March 10, 2020
Subcellular localization of legionella Dot/Icm effectors
Adam J Vogrin1, Aurelie Mousnier, Gad Frankel
1Department of Microbiology and Immunology, University of Melbourne, Melbourne, VIC, Australia.
Methods in Molecular Biology (Clifton, N.J.)
|November 15, 2012
Summary
Legionella pneumophila uses the Dot/Icm type IV secretion system to translocate effector proteins into host cells. Localizing these proteins reveals their function and targets within the host cell.
Area of Science:
- Microbiology
- Cell Biology
- Molecular Biology
Background:
- Legionella pneumophila utilizes the Dot/Icm type IV secretion system for intracellular survival.
- Translocated effector proteins are crucial for L. pneumophila pathogenesis.
- Understanding effector protein localization is key to elucidating their functions.
Purpose of the Study:
- To describe methods for determining the subcellular localization of Dot/Icm effector proteins.
- To provide protocols for visualizing effector protein function within host cells.
Main Methods:
- Ectopic expression of green fluorescent protein (GFP) fusions for cellular localization.
- Immuno-fluorescence microscopy of epitope-tagged effector proteins in infected host cells.
- Co-staining with host cell markers to identify specific subcellular compartments.
Main Results:
- Established protocols for localizing effector proteins within host cells.
- Demonstrated the utility of GFP fusions and immuno-fluorescence for visualizing effector protein localization.
- Linked effector protein localization to their potential host cell targets and mechanisms of action.
Conclusions:
- Subcellular localization is a critical determinant of Dot/Icm effector protein function.
- The described methods facilitate the study of Legionella-host interactions.
- Further research into effector localization will advance understanding of bacterial pathogenesis.
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