Opposing JAK-STAT and Wnt signaling gradients define a stem cell domain by regulating differentiation at two borders

  1. David Melamed
  2. Daniel Kalderon  Is a corresponding author
  1. Columbia University, United States

Abstract

Many adult stem cell communities are maintained by population asymmetry, where stochastic behaviors of multiple individual cells collectively result in a balance between stem cell division and differentiation. We investigated how this is achieved for Drosophila Follicle Stem Cells (FSCs) by spatially-restricted niche signals. FSCs produce transit-amplifying Follicle Cells (FCs) from their posterior face and quiescent Escort Cells (ECs) to their anterior. We show that JAK-STAT pathway activity, which declines from posterior to anterior, dictates the pattern of divisions over the FSC domain, promotes more posterior FSC locations and conversion to FCs, while opposing EC production. Wnt pathway activity declines from the anterior, promotes anterior FSC locations and EC production, and opposes FC production. The pathways combine to define a stem cell domain through concerted effects on FSC differentiation to ECs and FCs at either end of opposing signaling gradients, and impose a pattern of proliferation that matches derivative production.

Data availability

All data analysed are included in the manuscript and supporting files. One source data file includes numerical data for all Figures.

Article and author information

Author details

  1. David Melamed

    Biological Sciences, Columbia University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2102-1340
  2. Daniel Kalderon

    Biological Sciences, Columbia University, New York, United States
    For correspondence
    ddk1@columbia.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2149-0673

Funding

National Institutes of Health (RO1 GM079351)

  • Daniel Kalderon

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Valerie Horsley, Yale University, United States

Publication history

  1. Received: July 17, 2020
  2. Accepted: October 30, 2020
  3. Accepted Manuscript published: November 2, 2020 (version 1)
  4. Version of Record published: November 27, 2020 (version 2)

Copyright

© 2020, Melamed & Kalderon

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. David Melamed
  2. Daniel Kalderon
(2020)
Opposing JAK-STAT and Wnt signaling gradients define a stem cell domain by regulating differentiation at two borders
eLife 9:e61204.
https://doi.org/10.7554/eLife.61204

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