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Bioluminescence Imaging to Detect Late Stage Infection of African Trypanosomiasis
Published on: May 18, 2016
A quorum sensing-independent path to stumpy development in Trypanosoma brucei
Henriette Zimmermann1, Ines Subota1, Christopher Batram1
1Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany.
Plos Pathogens
|April 11, 2017
Summary
African trypanosomes use stumpy induction factor (SIF) for population control. A second pathway to tsetse infectivity, independent of SIF, is triggered by expressing a new variant surface glycoprotein (VSG).
Area of Science:
- Parasitology
- Molecular Biology
- Cell Biology
Background:
- African trypanosomes evade host immunity through antigenic variation, switching their surface Variant Surface Glycoprotein (VSG).
- Parasite population control is crucial for persistent infections, traditionally linked to quorum sensing via stumpy induction factor (SIF).
Purpose of the Study:
- To investigate alternative mechanisms regulating trypanosome differentiation to the tsetse-fly infective stumpy stage.
- To explore the link between antigenic variation and parasite development independent of SIF.
Main Methods:
- Analysis of gene expression and parasite differentiation in pleomorphic Trypanosoma brucei strains.
- Monitoring of VSG expression site (ES) transcriptional status and its correlation with stumpy development.
Main Results:
- A novel pathway to stumpy development was identified, triggered by the expression of a second VSG.
- This VSG-driven pathway leads to transcriptional attenuation of the VSG expression site (ES), inducing rapid stumpy formation.
- The process is independent of SIF and solely regulated by the ES transcriptional state, demonstrating phenotypic plasticity.
Conclusions:
- Trypanosome stumpy development is regulated by at least two distinct mechanisms: SIF-dependent quorum sensing and VSG-expression-dependent ES attenuation.
- ES attenuation offers a survival advantage by allowing for the rescue of failed antigenic switches, a previously underestimated factor.
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