1. Developmental Biology
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Diversification of heart progenitor cells by EGF signaling and differential modulation of ETS protein activity

  1. Benjamin Schwarz
  2. Dominik Hollfelder
  3. Katharina Scharf
  4. Leonie Hartmann
  5. Ingolf Reim  Is a corresponding author
  1. Friedrich-Alexander University of Erlangen-Nürnberg, Germany
Research Article
  • Cited 5
  • Views 1,048
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Cite this article as: eLife 2018;7:e32847 doi: 10.7554/eLife.32847

Abstract

For coordinated circulation, vertebrate and invertebrate hearts require stereotyped arrangements of diverse cell populations. This study explores the process of cardiac cell diversification in the Drosophila heart, focusing on the two major cardioblast subpopulations: generic working myocardial cells and inflow valve-forming ostial cardioblasts. By screening a large collection of randomly induced mutants we identified several genes involved in cardiac patterning. Further analysis revealed an unexpected, specific requirement of EGF signaling for the specification of generic cardioblasts and a subset of pericardial cells. We demonstrate that the Tbx20 ortholog Midline acts as a direct target of the EGFR effector Pointed to repress ostial fates. Furthermore, we identified Edl/Mae, an antagonist of the ETS factor Pointed, as a novel cardiac regulator crucial for ostial cardioblast specification. Combining these findings we propose a regulatory model in which the balance between activation of Pointed and its inhibition by Edl controls cardioblast subtype-specific gene expression.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, 3, 5 and 5-S1.

Article and author information

Author details

  1. Benjamin Schwarz

    Department of Biology, Division of Developmental Biology, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Dominik Hollfelder

    Department of Biology, Division of Developmental Biology, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Katharina Scharf

    Department of Biology, Division of Developmental Biology, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Leonie Hartmann

    Department of Biology, Division of Developmental Biology, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Ingolf Reim

    Department of Biology, Division of Developmental Biology, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
    For correspondence
    ingolf.reim@fau.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8069-5532

Funding

Deutsche Forschungsgemeinschaft (RE 2985/1-1)

  • Ingolf Reim

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

Publication history

  1. Received: October 16, 2017
  2. Accepted: June 4, 2018
  3. Accepted Manuscript published: June 5, 2018 (version 1)
  4. Version of Record published: July 5, 2018 (version 2)

Copyright

© 2018, Schwarz 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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