Event Abstract Back to Event Tunic microbiome of a global ascidian invader Xavier Turon1*, Maria Casso1, 2, Marta T. Rodrigo1, Núria Marco2 and Marta Pascual2 1 Center for Advanced Studies of Blanes, Superior Council of Scientific Investigations, Spain 2 Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Spain The tunic of the ascidians shows a high diversity of prokaryote symbionts, which may play an important role in the species’ biology, adaptation and survival. The global invader Didemnum vexillum provides a unique opportunity to assess the patterns of variability of ascidian microbiomes. In particular, do they remain stable as the host species colonises new habitats or do they shift according to local environment? We have sequenced 16S amplicons of the microbiome of 60 D. vexillum colonies from 2 native (Japan) and 10 introduced populations spanning the known distribution of the species. We found 2,984 zero-radius OTUs (ZOTUs) belonging to 36 bacterial and 3 archaeal phyla. The microbiome had a markedly different composition from surrounding seawater. Only 8 ZOTUs (0.27%) were present in all colonies and 47 (1.58%) were present in all localities. However, these ZOTUs represented the 71.31 and 89.60%, respectively, of the total number of reads obtained. Thus, the species showed a high-abundance but low-diversity core microbiome. The variable component is quantitatively much less important but comprises a highly diverse assemblage. This component differs within localities (0.59 average Bray-Curtis distance), but even more between localities (0.70) and between described genetic groups of the ascidian (0.74). The average of exclusive ZOTUs was 11.95% in each colony and 22.05% in each locality. The combination of a quantitatively dominant core component and a highly diverse variable fraction in the microbiome of D. vexillum can contribute to the success of this global invader in their expansion to different environments. Acknowledgements We are indebted to all people that contributed samples for this study: Gretchen Lambert, Ian Davidson, Judith Pederson, and Gaku Kumano. We specially thank Carles Bori, Davide Tagliapietra, Marco Sigovini and Irene Guarneri for their help during sampling in Ebro Delta and Venice. This research was funded by project PopCOmics (TM2017-88080) from the Spanish Government. This is a contribution from the Consolidated Research Group “Benthic Biology and Ecology” SGR2017-1120 (Catalan Government). Keywords: invasive species, microbiome, Symbiosis, adaptation, Didemnum vexillum Conference: XX Iberian Symposium on Marine Biology Studies (SIEBM XX) , Braga, Portugal, 9 Sep - 12 Sep, 2019. Presentation Type: Poster Presentation Topic: Global Change, Invasive Species and Conservation Citation: Turon X, Casso M, Rodrigo MT, Marco N and Pascual M (2019). Tunic microbiome of a global ascidian invader. Front. Mar. Sci. Conference Abstract: XX Iberian Symposium on Marine Biology Studies (SIEBM XX) . doi: 10.3389/conf.fmars.2019.08.00171 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 14 May 2019; Published Online: 27 Sep 2019. * Correspondence: Prof. Xavier Turon, Center for Advanced Studies of Blanes, Superior Council of Scientific Investigations, Blanes, Spain, xturon@ceab.csic.es Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Xavier Turon Maria Casso Marta T Rodrigo Núria Marco Marta Pascual Google Xavier Turon Maria Casso Marta T Rodrigo Núria Marco Marta Pascual Google Scholar Xavier Turon Maria Casso Marta T Rodrigo Núria Marco Marta Pascual PubMed Xavier Turon Maria Casso Marta T Rodrigo Núria Marco Marta Pascual Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.