Embryonic geometry underlies phenotypic variation in decanalized conditions

  1. Anqi Huang
  2. Jean-François Rupprecht
  3. Timothy E Saunders  Is a corresponding author
  1. National University of Singapore, Singapore
  2. CNRS and Turing Center for Living Systems, France

Abstract

During development, many mutations cause increased variation in phenotypic outcomes, a phenomenon termed decanalization. Phenotypic discordance is often observed in the absence of genetic and environmental variations, but the mechanisms underlying such inter-individual phenotypic discordance remain elusive. Here, using the anterior-posterior (AP) patterning of the Drosophila embryo, we identified embryonic geometry as a key factor predetermining patterning outcomes under decanalizing mutations. With the wild-type AP patterning network, we found that AP patterning is robust to variations in embryonic geometry; segmentation gene expression remains reproducible even when the embryo aspect ratio is artificially reduced by more than twofold. In contrast, embryonic geometry is highly predictive of individual patterning defects under decanalized conditions of either increased bicoid (bcd) dosage or bcd knockout. We showed that the phenotypic discordance can be traced back to variations in the gap gene expression, which is rendered sensitive to the geometry of the embryo under mutations.

Data availability

All data generated or analysed during this study are included in the manuscript and supplementary files.

Article and author information

Author details

  1. Anqi Huang

    Mechanobiology Institute, National University of Singapore, Singapore, Singapore
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0551-1160
  2. Jean-François Rupprecht

    Centre de Physique Théorique, CNRS and Turing Center for Living Systems, Marseille, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Timothy E Saunders

    Mechanobiology Institute, National University of Singapore, Singapore, Singapore
    For correspondence
    dbsste@nus.edu.sg
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5755-0060

Funding

National Research Foundation Singapore (NRF2012NRF-NRFF001-094)

  • Timothy E Saunders

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

Version history

  1. Received: April 3, 2019
  2. Accepted: February 11, 2020
  3. Accepted Manuscript published: February 12, 2020 (version 1)
  4. Version of Record published: February 20, 2020 (version 2)

Copyright

© 2020, Huang 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. Anqi Huang
  2. Jean-François Rupprecht
  3. Timothy E Saunders
(2020)
Embryonic geometry underlies phenotypic variation in decanalized conditions
eLife 9:e47380.
https://doi.org/10.7554/eLife.47380

Share this article

https://doi.org/10.7554/eLife.47380

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