The genetic factors of bilaterian evolution
- Universitaet zu Koeln, Germany
- Sichuan University, China
- University of Cologne, Germany
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.
Data availability
Accession numbers and/or URLs for previously published transcriptome datasets are listed in Supplementary file 3. Download links for previously published genomic sequences are listed in Supplementary File 1-Supplementary Table S7.Orthology datasets generated in this study have been deposited to Dryad, under the doi:10.5061/dryad.4qf7168
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Data from: The genetic factors of bilaterian evolutionDryad Digital Repository, doi:10.5061/dryad.4qf7168.
Article and author information
Author details
Kristen A Panfilio
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
- Patricia J Wittkopp, University of Michigan, United States
Version history
- Received: January 31, 2019
- Accepted: July 3, 2020
- Accepted Manuscript published: July 16, 2020 (version 1)
- 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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The genetic factors of bilaterian evolution
eLife 9:e45530.
https://doi.org/10.7554/eLife.45530
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