1. Evolutionary Biology
  2. Genetics and Genomics
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The genetic factors of bilaterian evolution

  1. Peter Heger  Is a corresponding author
  2. Wen Zheng
  3. Anna Rottmann
  4. Kristen A Panfilio
  5. Thomas Wiehe
  1. Universitaet zu Koeln, Germany
  2. Sichuan University, China
  3. University of Cologne, Germany
Research Article
  • Cited 2
  • Views 2,501
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Cite this article as: eLife 2020;9:e45530 doi: 10.7554/eLife.45530

Abstract

The Cambrian explosion was a unique animal radiation ~540 million years ago that produced the full range of body plans across bilaterians. The genetic mechanisms underlying these events are unknown, leaving a fundamental question in evolutionary biology unanswered. Using large-scale comparative genomics and advanced orthology evaluation techniques, we identified 157 bilaterian-specific genes. They include the entire Nodal pathway, a key regulator of mesoderm development and left-right axis specification; components for nervous system development, including a suite of G protein-coupled receptors that control physiology and behaviour, the Robo-Slit midline repulsion system, and the neurotrophin signalling system; a high number of zinc finger transcription factors; and novel factors that previously escaped attention. Contradicting the current view, our study reveals that genes with bilaterian origin are robustly associated with key features in extant bilaterians, suggesting a causal relationship.

Article and author information

Author details

  1. Peter Heger

    Institute for Genetics, Universitaet zu Koeln, Cologne, Germany
    For correspondence
    peter.heger@uni-koeln.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2583-2981
  2. Wen Zheng

    West China-Washington Mitochondria and Metabolism Research Center, Sichuan University, Chengdu, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Anna Rottmann

    Institute for Genetics, Universitaet zu Koeln, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Kristen A Panfilio

    Institute for Zoology/Developmental Biology, University of Cologne, Köln, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6417-251X
  5. Thomas Wiehe

    Institut fuer Genetik, Universitaet zu Koeln, Koeln, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8932-2772

Funding

Deutsche Forschungsgemeinschaft (CRC~680 and CRC~1211)

  • Thomas Wiehe

Deutsche Forschungsgemeinschaft (CRC~680)

  • Kristen A Panfilio

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

Reviewing Editor

  1. Patricia J Wittkopp, University of Michigan, United States

Publication history

  1. Received: January 31, 2019
  2. Accepted: July 3, 2020
  3. Accepted Manuscript published: July 16, 2020 (version 1)
  4. Version of Record published: October 5, 2020 (version 2)

Copyright

© 2020, Heger 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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