The Toll pathway inhibits tissue growth and regulates cell fitness in an infection-dependent manner
Abstract
The Toll pathway regulates the cellular response to infection via the transcriptional upregulation of antimicrobial peptides. In Drosophila, apart from its role in innate immunity, this pathway has also been reported to be important for the elimination of loser cells in a process referred to as cell competition, which can be locally triggered by secreted factors released from winner cells. In this work we provide evidence that the inhibition of Toll signaling not only increases the fitness of loser cells, but also bestows a clonal growth advantage on wild-type cells. We further demonstrate that this growth advantage depends on basal infection levels since it is no longer present under axenic conditions but exacerbated upon intense pathogen exposure. Thus, the Toll pathway functions as a fine-tuned pro-apoptotic and anti-proliferative regulator, underlining the existence of a trade-off between innate immunity and growth during development.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Funding
Forschungskredit Candoc University of Zurich
- Federico Germani
Swiss National Science Foundation
- Daniel Hain
Swiss National Science Foundation
- Eduardo Moreno
ERC
- Daniel Hain
ERC
- Eduardo Moreno
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Germani et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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