Quantitative system drift compensates for altered maternal inputs to the gap gene network of the Scuttle Fly Megaselia abdita

  1. Karl R Wotton
  2. Eva Jiménez-Guri
  3. Anton Crombach
  4. Hilde Janssens
  5. Anna Alcaine-Colet
  6. Steffen Lemke
  7. Urs Schmidt-ott
  8. Johannes Jaeger  Is a corresponding author
  1. Centre for Genomic Regulation, Spain
  2. Ruprecht Karls University, Germany
  3. University of Chicago, United States

Abstract

The segmentation gene network in insects can produce equivalent phenotypic outputs despite differences in upstream regulatory inputs between species. We investigate the mechanistic basis of this phenomenon through a systems-level analysis of the gap gene network in the scuttle fly Megaselia abdita (Phoridae). It combines quantification of gene expression at high spatio-temporal resolution with systematic knock-downs by RNA interference (RNAi). Initiation and dynamics of gap gene expression differ markedly between M. abdita and Drosophila melanogaster, while the output of the system converges to equivalent patterns at the end of the blastoderm stage. Although the qualitative structure of the gap gene network is conserved, there are differences in the strength of regulatory interactions between species. We term such network rewiring 'quantitative system drift'. It provides a mechanistic explanation for the developmental hourglass model in the dipteran lineage. Quantitative system drift is likely to be a widespread mechanism for developmental evolution.

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Author details

  1. Karl R Wotton

    European Molecular Biology Laboratory, CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain
    Competing interests
    The authors declare that no competing interests exist.
  2. Eva Jiménez-Guri

    European Molecular Biology Laboratory, CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain
    Competing interests
    The authors declare that no competing interests exist.
  3. Anton Crombach

    European Molecular Biology Laboratory, CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain
    Competing interests
    The authors declare that no competing interests exist.
  4. Hilde Janssens

    European Molecular Biology Laboratory, CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain
    Competing interests
    The authors declare that no competing interests exist.
  5. Anna Alcaine-Colet

    European Molecular Biology Laboratory, CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain
    Competing interests
    The authors declare that no competing interests exist.
  6. Steffen Lemke

    Centre for Organismal Studies, Ruprecht Karls University, Heidelberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Urs Schmidt-ott

    Department of Organismal Biology and Anatomy, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Johannes Jaeger

    European Molecular Biology Laboratory, CRG Systems Biology Research Unit, Centre for Genomic Regulation, Barcelona, Spain
    For correspondence
    yogi.jaeger@crg.eu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Wotton 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. Karl R Wotton
  2. Eva Jiménez-Guri
  3. Anton Crombach
  4. Hilde Janssens
  5. Anna Alcaine-Colet
  6. Steffen Lemke
  7. Urs Schmidt-ott
  8. Johannes Jaeger
(2015)
Quantitative system drift compensates for altered maternal inputs to the gap gene network of the Scuttle Fly Megaselia abdita
eLife 4:e04785.
https://doi.org/10.7554/eLife.04785

Share this article

https://doi.org/10.7554/eLife.04785

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