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Updated: Aug 11, 2026
05:50
Assessing the Cellular Immune Response of the Fruit Fly, Drosophila melanogaster, Using an In Vivo Phagocytosis Assay
Published on: April 10, 2019
Anthrax lethal factor and edema factor act on conserved targets in Drosophila
Annabel Guichard1, Jin Mo Park, Beatriz Cruz-Moreno
1Section of Cell and Developmental Biology, University of California at San Diego, La Jolla, 92093-0349, USA.
Summary
Anthrax toxins lethal factor (LF) and edema factor were studied in Drosophila. These toxins function similarly to mammalian cells, validating Drosophila as a model for toxin research.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Bacterial toxins often target conserved host-signaling pathways.
- Genetic model organisms offer valuable systems for studying toxin mechanisms.
- Anthrax toxins, lethal factor (LF) and edema factor, are key virulence factors.
Purpose of the Study:
- To characterize the activity of anthrax toxins LF and edema factor in transgenic Drosophila.
- To investigate the conserved function of these toxins in a multicellular model organism.
- To establish Drosophila as a system for studying toxin-host interactions.
Main Methods:
- Expression of LF and edema factor in transgenic Drosophila.
- In vitro cleavage assays of Drosophila MAPK kinases (MAPKKs) by LF.
- Analysis of signaling pathway inhibition (MAPK, Hedgehog) during Drosophila development (embryonic dorsal closure, adult thoracic closure, wing development).
- Epistasis experiments to determine the level of toxin action.
Main Results:
- LF cleaved Drosophila MAPKKs Hemipterous (Hep) and Licorne in vitro.
- LF inhibited Hep/c-Jun N-terminal kinase and Ras/MAPK signaling pathways in Drosophila.
- LF acted at the level of Hep and Dsor, upstream of MAPK and downstream of Raf.
- Edema factor inhibited the Hedgehog (hh) pathway, consistent with cAMP-dependent PKA activity.
Conclusions:
- Anthrax toxins LF and edema factor exhibit conserved functions in Drosophila, mirroring their activity in mammalian cells.
- Drosophila serves as a valid multicellular model system for studying the in vivo mechanisms of bacterial toxins and virulence factors.
- This study validates the utility of Drosophila for dissecting complex toxin-host interactions.
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