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Keynote and Oral Papers European Journal of Phycology ISSN: 0967-0262 (Print) 1469-4433 (Online) Journal homepage: https://www.tandfonline.com/loi/tejp20 Keynote and Oral Papers To cite this article: (2019) Keynote and Oral Papers, European Journal of Phycology, 54:sup1, 31-117, DOI: 10.1080/09670262.2019.1626627 To link to this article: https://doi.org/10.1080/09670262.2019.1626627 Published online: 20 Aug 2019. Submit your article to this journal Article views: 89 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=tejp20 EUROPEAN JOURNAL OF PHYCOLOGY 2019, VOL. 54, NO. S1, 31–117 https://doi.org/10.1080/09670262.2019.1626627 Keynote and Oral Papers 1. Phylogeny in the ‘omics’ era: new approaches for the study of the evolution of algae and their organelles 1KN.1 those, CASH lineages have plastids related to red algae, but the mechanisms by which they were DIVERSIFICATION TRENDS IN THE ARCHAEPLASTIDA INFERRED FROM acquired remain unclear. Contrary to expectations CHLOROPLAST GENOME DATA of secondary endosymbiotic models, a sizable part of their plastid-targeted genes is not from the same Heroen Verbruggen ([email protected]) origin as the plastid itself. Scenarios as the ancestral cryptic serial endosymbioses or the shopping bag model University of Melbourne, Parkville, Victoria 3010, Australia provide a substantial interpretation of this gene mosaicism but are exclusively focusing on an endo- Thanks to high-throughput sequencing, it has symbiotic mechanism. Similarly, while the Rhodoplex become easier and cheaper than ever to generate hypothesis fits the single phylogenetic origin of com- genome-scale data for a broad array of non-model plex red plastids, it does not explain gene mosaicism. species. This offers great perspectives to improve our Moreover, it implies multiple tertiary (or quaternary) understanding of algal classification and evolutionary endosymbiotic events, whereas most complex algae biology. We inferred phylogeny of the Archaeplastida do not bear nucleomorphs and only have 3 or 4 using >460 chloroplast genomes and calibrated in membranes surrounding their plastids. To overcome time using 19 fossil occurrences, providing a mostly the inconsistencies of those models, we propose klep- resolved picture of the phylogenetic history of the toplasty as an additional mechanism for explaining group. We used the time-calibrated phylogeny to plastid spread in CASH lineages. In line with the investigate patterns of diversification through time shopping bag model, our hypothesis posits multiple and across lineages, showing an increase of lineage transient interactions with preys of diverse origins accumulation during the Paleozoic, with stark differ- but also proposes a rationale for the selective force ences between the contributions of different func- driving the progressive accumulation of plastid- tional form-groups to overall diversification. targeted genes: to maintain functional kleptoplastids for increasingly longer periods of time, before ulti- 1KN.2 mately reducing them into fully integrated plastids. In such a scenario, the phylogenetic diversity of plastid- AUTOMATED BIOINFORMATICS targeted genes would be higher than predicted with APPROACHES TO EVALUATE THE RELATIVE endosymbiotic models, where genes originate mostly CONTRIBUTION OF ENDOSYMBIOSIS AND from a single source, the algal symbiont. To test our KLEPTOPLASTY IN THE EVOLUTION OF hypothesis, we designed and implemented an auto- COMPLEX RED ALGAE mated pipeline for building and parsing gene trees in Mick Van Vlierberghe (mvanvlierberghe@doct. a discovery-driven and taxonomy-aware fashion. This uliege.be) and Denis Baurain (denis.baurain@u- approach allows us to infer whether any given CASH liege.be) alga rather arose through endosymbiosis or klepto- plasty by reading its position on an alpha-diversity – InBioS PhytoSYSTEMS, Eukaryotic Phylogenomics, University ladder, ranging from (theoretically) single-source of Liège, Liège, Belgium nucleomorph-bearing organisms (e.g., Guillardia Complex algae form a network of photosynthetic theta) to multiple-source kleptoplastic organisms organisms spread across the eukaryotic tree. Among (e.g., Dinophysis acuminata). © 2019 British Phycological Society Published online 20 Aug 2019 32 KEYNOTE AND ORAL PAPERS 1OR.1 The red algal order Ceramiales was previously arranged on the basis of morphological studies into five families: FACILITATED MITOCHONDRIAL EVOLUTION Ceramiaceae, Dasyaceae, Delesseriaceae, Rhodomelaceae OF AN EXTREMOPHILIC RED ALGAE and Sarcomeniaceae. The first phylogenies based on one 1 Chung Hyun Cho ([email protected]), Seung In or two molecular markers failed to produce well-resolved Park1 ([email protected]), Claudia Ciniglia2 phylogenies or to resolve the first three families as mono- ([email protected]) and Hwan Su phyletic. At present, nine families are recognized in the Yoon1 ([email protected]) Ceramiales after the split of the Ceramiaceae into five families. Moreover, the Delesseriaceae and Dasyaceae 1 Department of Biological Sciences, Sungkyunkwan University, include three and two subfamilies, respectively. 2066 Seobu-ro, Jangan-gu, 16419 Suwon, Korea and 2Department of Environmental, Biological and Pharmaceutical However, relationships among families and subfamilies Science and Technology, University of Campania “L. are poorly understood. Recent advances in High Vanvitelli”, Viale Abramo Lincoln, 5, 81100 Caserta, Italy Throughput Sequencing techniques facilitate the sequen- cing of plastid genomes, which have been used for resol- It is generally fatal in harsh conditions to the most of ving challenging phylogenies in the red algae. In this species, but some species can thrive in extreme environ- study, we attempted to produce a well-resolved ments including high temperature, acidic, and heavy- phylogeny for the order Ceramiales using 80 (27 newly metal rich conditions. Compare to many prokaryotic sequenced) plastid genomes representative of the major extremophiles, only a few eukaryotic species are reported lineages. We aligned and concatenated 208 plastid from this environment. The Cyanidiophyceae coding sequences (CDSs) that we used to construct (Rhodophyta) are the best eukaryotic example that thrive a maximum likelihood tree. The resulting phylogeny in acidic (pH 0-2), and high-temperature habitats (35- resolved most of the nodes with full support and showed 50°C). Study on this interesting organism, however, is that a family-level reclassification is required. The poorly conducted. To fill the gap of our understanding of Rhodomelaceae, Ceramiaceae and Wrangeliaceae were the cyanidiophycean biology, we have completely resolved as monophyletic and we propose to maintain sequenced and annotated five new mitogenomes from their current circumscription. By contrast, the families the representative clades of Cyanidiophyceae. In this Callithamniaceae, Dasyaceae, Delesseriaceae, Sarcome- study, we addressed two different issues; i) resolving the niaceae, Spyridiaceae and Inkyuleeaceae require revision. phylogenetic relationship and ii) the classification of mitochondria type in Cyanidiophyceae. To this end, we compared trees based on a concatenated gene set and 1OR.3 sub-sampled datasets. The relationship between the “ ” major lineages of Cyanidiophyceae has been resolved RAPPEMONADS IS THE THIRD LINEAGE OF from our analysis. We also distinguished two mitochon- HAPTOPHYTA drial types, Cyanidium-type and Galdieria-type, based on Ryoma Kamikawa1 ([email protected]. their distinctive features of mitogenomes. The result jp), Azusa Itoh1 ([email protected]), represents that a strong selective pressure affected mito- Motoki Kayama1 ([email protected]. chondria of Galidieria-type, which are altered the protein jp), Mami Nomura1 ([email protected]), Takuro properties of mitochondrial genes. Based on comprehen- Nakayama2 ([email protected]), Hideaki sive genomic analyses, we will provide insights into the Miyashita1 ([email protected])and evolutionary history of Cyanidiophyceae. Masanobu Kawachi3 ([email protected]) 1Graduate School of Human and Environmental Studies, Kyoto 1OR.2 University, Kyoto, Kyoto 606-8501, Japan; 2Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578, PHYLOGENOMICS OF THE RED ALGAL Japan and 3The National Institute for Environmental Studies, ORDER CERAMIALES: IMPLICATIONS FOR Tsukuba, Ibaraki 305-8506, Japan FAMILY LEVEL CLASSIFICATION “Rappemonads” is a monophyletic plastid-bearing 1,2 2 Pilar Díaz-Tapia ([email protected]), Marisa M. Pasella lineage that is comprised of only environmental 2 ([email protected]), Heroen Verbruggen (heroen. DNA sequences in the plastid 16S rRNA tree. [email protected]) and Christine A. Maggs3 “Rappemonads” is not nested in any of algal clades ([email protected]) in the phylogenetic tree, and therefore “Rappemonads” is thought to be a novel lineage independent from any 1 Coastal Biology Research Group, University of A Coruña, of known major algal groups. However, because no A Coruña, Spain; 2School of BioSciences, University of Melbourne, Melbourne, Australia and 3Portaferry Marine one could have succeeded in the observation of living Laboratory, Queen’s University Belfast, Northern Ireland cells of “Rappemonads,” identity of this eukaryotic EUROPEAN JOURNAL OF PHYCOLOGY 33 group has been unknown. In this study, we
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