Insights into early animal evolution form the genome of the xenacoelomorph worm Xenoturbella bocki
- University of Cologne, Germany
- University College London, United Kingdom
- Durham University, United Kingdom
- Université Côte d'Azur, France
- UiT The Arctic University of Norway, Norway
- Institut Pasteur, France
- University of Greifswald, Germany
- University of Chicago, United States
- Sorbonne Université, France
- University of Oxford, United Kingdom
Abstract
The evolutionary origins of Bilateria remain enigmatic. One of the more enduring proposals highlights similarities between a cnidarian-like planula larva and simple acoel-like flatworms. This idea is based in part on the view of the Xenacoelomorpha as an outgroup to all other bilaterians which are themselves designated the Nephrozoa (protostomes and deuterostomes). Genome data can provide important comparative data and help to understand the evolution and biology of enigmatic species better. Here we assemble and analyse the genome of the simple, marine xenacoelomorph Xenoturbella bocki, a key species for our understanding of early bilaterian evolution. Our highly contiguous genome assembly of X. bocki has a size of ~111 Mbp in 18 chromosome like scaffolds, with repeat content and intron, exon and intergenic space comparable to other bilaterian invertebrates. We find X. bocki to have a similar number of genes to other bilaterians and to have retained ancestral metazoan synteny. Key bilaterian signalling pathways are also largely complete and most bilaterian miRNAs are present. Overall, we conclude that X. bocki has a complex genome typical of bilaterians, which does not reflect the apparent simplicity of its body plan that has been so important to proposals that the Xenacoelomorpha are the simple sister group of the rest of the Bilateria.
Data availability
All read sets (RNA and DNA derived) used in this study will be made available with the publication of this manuscript on the SRA database under the BioProject ID PRJNA864813. Hi-C reads are deposited under SAMN30224387, RNA-Seq under SAMN35083895. The genome assemblies of X. bocki (ERS12565994, ERA16814408) and the Chlamydia sp. (ERS12566084, ERA16814775) are deposited under PRJEB55230 at ENA.Supplementary online material (described in the manuscript) has be made available on Zenodo: doi:10.5281/zenodo.6962271
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Supplementary files for the Xenoturbella bocki genome analysisdoi:10.5281/zenodo.6962271.
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The genome of Xenoturbella bockiNCBI BioProject, PRJNA864813.
Article and author information
Author details
Philipp H Schiffer
Maximilian J Telford
Funding
European Research Council (ERC-2012-AdG 322790)
- Philipp H Schiffer
- Helen E Robertson
- Anne C Zakrzewski
- Steven Mueller
- Maximilian J Telford
Deutsche Forschungsgemeinschaft (434028868)
- Philipp H Schiffer
Biotechnology and Biological Sciences Research Council (BB/R016240/1)
- Paschalis Natsidis
- Maximilian J Telford
Leverhulme Trust (RPG-2018-302)
- Daniel J Leite
- Maximilian J Telford
HORIZON EUROPE Marie Sklodowska-Curie Actions (764840 IGNITE)
- Paschalis Natsidis
- Maximilian J Telford
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Ariel D. Chipman, The Hebrew University of Jerusalem, Israel
Version history
- Received: November 30, 2023
- Accepted: July 3, 2024
- Accepted Manuscript published: August 7, 2024 (version 1)
Copyright
© 2024, Schiffer 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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Insights into early animal evolution form the genome of the xenacoelomorph worm Xenoturbella bocki
eLife 13:e94948.
https://doi.org/10.7554/eLife.94948
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