The Toll pathway inhibits tissue growth and regulates cell fitness in an infection-dependent manner

  1. Federico Germani  Is a corresponding author
  2. Daniel Hain
  3. Denise Sternlicht
  4. Eduardo Moreno  Is a corresponding author
  5. Konrad Basler  Is a corresponding author
  1. University of Zurich, Switzerland
  2. University of Bern, Switzerland
  3. Champalimaud Research Center, Portugal

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.

Article and author information

Author details

  1. Federico Germani

    Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
    For correspondence
    federico.germani@uzh.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5604-0437
  2. Daniel Hain

    Institute of Cell Biology, University of Bern, Bern, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Denise Sternlicht

    Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Eduardo Moreno

    Champalimaud Research Center, Lisbon, Portugal
    For correspondence
    eduardo.moreno@research.fchampalimaud.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5040-452X
  5. Konrad Basler

    Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
    For correspondence
    kb@imls.uzh.ch
    Competing interests
    The authors declare that no competing interests exist.

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.

Reviewing Editor

  1. Utpal Banerjee, University of California, Los Angeles, United States

Version history

  1. Received: July 9, 2018
  2. Accepted: November 16, 2018
  3. Accepted Manuscript published: November 19, 2018 (version 1)
  4. Version of Record published: December 4, 2018 (version 2)
  5. Version of Record updated: January 4, 2019 (version 3)
  6. Version of Record updated: February 14, 2019 (version 4)

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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  1. Federico Germani
  2. Daniel Hain
  3. Denise Sternlicht
  4. Eduardo Moreno
  5. Konrad Basler
(2018)
The Toll pathway inhibits tissue growth and regulates cell fitness in an infection-dependent manner
eLife 7:e39939.
https://doi.org/10.7554/eLife.39939

Share this article

https://doi.org/10.7554/eLife.39939

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