A re-inducible gap gene cascade patterns the anterior-posterior axis of insects in a threshold-free fashion

  1. Alena Boos
  2. Jutta Distler
  3. Heike Rudolf
  4. Martin Klingler  Is a corresponding author
  5. Ezzat El-Sherif  Is a corresponding author
  1. Friedrich-Alexander Universität Erlangen-Nürnberg, Germany

Abstract

Gap genes mediate the division of the anterior-posterior axis of insects into different fates through regulating downstream hox genes. Decades of tinkering the segmentation gene network of Drosophila melanogaster led to the conclusion that gap genes are regulated (at least initially) through a threshold-based mechanism, guided by both anteriorly- and posteriorly-localized morphogen gradients. In this paper, we show that the response of the gap gene network in the beetle Tribolium castaneum upon perturbation is consistent with a threshold-free 'Speed Regulation' mechanism, in which the speed of a genetic cascade of gap genes is regulated by a posterior morphogen gradient. We show this by re-inducing the leading gap gene (namely, hunchback) resulting in the re-induction of the gap gene cascade at arbitrary points in time. This demonstrates that the gap gene network is self-regulatory and is primarily under the control of a posterior regulator in Tribolium and possibly other short/intermediate-germ insects.

Data availability

Numerical data and sample sizes are all documented in Figure 4-source data 1, Figure 5-source data 1, and Figure 5-source data 2

Article and author information

Author details

  1. Alena Boos

    Department of Biology, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Jutta Distler

    Department of Biology, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Heike Rudolf

    Department of Biology, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Martin Klingler

    Department of Biology, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
    For correspondence
    martin.klingler@fau.de
    Competing interests
    The authors declare that no competing interests exist.
  5. Ezzat El-Sherif

    Department of Biology, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
    For correspondence
    ezzat.el-sherif@fau.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1738-8139

Funding

Alexander von Humboldt-Stiftung (Fellowship)

  • Ezzat El-Sherif

Deutsche Forschungsgemeinschaft (KL 656_5-1)

  • Martin Klingler

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

Reviewing Editor

  1. Naama Barkai, Weizmann Institute of Science, Israel

Publication history

  1. Received: August 17, 2018
  2. Accepted: December 19, 2018
  3. Accepted Manuscript published: December 20, 2018 (version 1)
  4. Version of Record published: January 11, 2019 (version 2)

Copyright

© 2018, Boos 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. Alena Boos
  2. Jutta Distler
  3. Heike Rudolf
  4. Martin Klingler
  5. Ezzat El-Sherif
(2018)
A re-inducible gap gene cascade patterns the anterior-posterior axis of insects in a threshold-free fashion
eLife 7:e41208.
https://doi.org/10.7554/eLife.41208

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