The slow evolving genome of the xenacoelomorph worm *Xenoturbella bocki*use asterix (*) to get italics

Philipp H. Schiffer, Paschalis Natsidis, Daniel J. Leite, Helen Robertson, François Lapraz, Ferdinand Marlétaz, Bastian Fromm, Liam Baudry, Fraser Simpson, Eirik Høye, Anne-C. Zakrzewski, Paschalia Kapli, Katharina J. Hoff, Steven Mueller, Martial Marbouty, Heather Marlow, Richard R. Copley, Romain Koszul, Peter Sarkies, Maximilian J. TelfordPlease use the format "First name initials family name" as in "Marie S. Curie, Niels H. D. Bohr, Albert Einstein, John R. R. Tolkien, Donna T. Strickland"

2023

<p style="text-align: justify;">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 help to elucidate phylogenetic relationships and provide important comparative data. Here we assemble and analyse the genome of the simple, marine xenacoelomorph <em>Xenoturbella bocki</em>, a key species for our understanding of early bilaterian and deuterostome evolution. Our highly contiguous genome assembly of X. bocki has a size of ~110 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. We conclude that <em>X. bocki</em> has a complex genome typical of bilaterians, in contrast to the apparent simplicity of its body plan. Overall, our data do not provide evidence supporting the idea that Xenacoelomorpha are a primitively simple outgroup to other bilaterians and gene presence/absence data support a relationship with Ambulacraria.</p>

https://www.ncbi.nlm.nih.gov/sra/?term=SAMN30224387, https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA864813You should fill this box only if you chose 'All or part of the results presented in this preprint are based on data'. URL must start with http:// or https://

https://github.com/willpett/metazoa-gene-content, https://github.com/sinanugur/MirMachine, https://github.com/koszullab/hicstuff, https://github.com/reubwn/hgtYou should fill this box only if you chose 'Scripts were used to obtain or analyze the results'. URL must start with http:// or https://

Xenoturbella, Bilateria, Xenacoelomorpha, Deuterostomia, morphological simplicity, genome evolution

NonePlease indicate the methods that may require specialised expertise during the peer review process (use a comma to separate various required expertises).

Evolutionary genomics

Christopher Cameron <c.cameron@umontreal.ca>, Lowe Christopher <clowe@stanford.edu>, Nicole King <nicoleking.ucb@gmail.com>, Gert Woerhide <woerheide@lmu.de>, Mark Blaxter <mb35@sanger.ac.uk>, Oleg Simakov <oleg.simakov@univie.ac.at> No need for them to be recommenders of PCI Genomics. Please do not suggest reviewers for whom there might be a conflict of interest. Reviewers are not allowed to review preprints written by close colleagues (with whom they have published in the last four years, with whom they have received joint funding in the last four years, or with whom they are currently writing a manuscript, or submitting a grant proposal), or by family members, friends, or anyone for whom bias might affect the nature of the review - see the code of conduct

Andreas Hejnol, Pedro Martineze.g. John Doe [john@doe.com]

2022-11-01 12:31:53

Rosa Fernández