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Patrick Keeling and Fabien Burki wrote a commentary on this excellent paper describing the mechanism of protein import in the complex plastids of dinoflagellate kareniaceans. Keeling, P.J., and Burki, F. (2025). Evolution: Untangling the mix of plastid endosymbiosis events. Curr. Biol. 35, R94–R96. https://doi.org/10.1016/j.cub.2024.12.005.  We are very excited about the release of this story. New deep-branching environmental plastid genomes on the algal tree of life Marine algae support the entire ocean ecosystem and greatly impact planetary biology. The availability of algae in culture poorly represents their large environmental diversity, and we still have a limited understanding of their convoluted evolution by endosymbiosis. Here, we performed a phylogeny-guided plastid genome-resolved metagenomic survey of Tara Oceans expeditions. We present a manually curated resource of nearly 700 new non-redundant plastid genomes of environmental pelagic algae. This catalogue vastly expands the plastid genome diversity within major algal groups, often corresponding to algae without closely related reference genomes. We also recovered four genomes, including one near complete, forming a deep-branching plastid lineage of nano-size algae (<5 μm) that we informally named leptophytes. This group is globally distributed and generally rare, although it can reach relatively high abundance notably in the Arctic. Leptophytes encompass the enigmatic marine plastid group DPL-2, one of the very few known plastid groups not clearly belonging to any major algal groups and for which only 16S amplicon data is available. Extensive phylogenetic analyses based on 93 plastid genes and gene content comparison firmly place leptophytes together with haptophytes and cryptophytes, although the exact relationships remain ambiguous. Collectively, our study demonstrates that metagenomics can reveal currently hidden diversity of organellar genomes, and shows the importance of including this diversity to improve models for plastid evolution. Jamy, M., Huber, T., Antoine, T., Ruscheweyh, H.-J., Paoli, L., Pelletier, E., Delmont, T.O., and Burki, F. (2025). bioRxiv, 2025.01.16.633336. https://doi.org/10.1101/2025.01.16.633336.   View from the lab at the Hakai research station on Calvert Island (British Columbia, Canada). During his short sabbatical, Fabien had the opportunity to visit this remote research station in the wilderness of beautiful British Columbia. Besides successful science, this was an incredible experience. Fresh cells from this channel everyday!
We've just had an incredible stretch of good BBQ weather, which was turned into a small celebration for Anne's PhD half-time presentation. She did a strong act presenting her accomplishments and future work on the symbiosis in Meringosphaera. A special thank to the opponent Anna Karnkowska, from the University of Warsaw, for her insightful comments and suggestions.  We have just published a comparative genomic analyses of Ascetosporea parasites, including new genome data for Bonamia ostreae (Haplosporida), Marteilia pararefringens and Paramarteilia canceri (Paramyxida), and that of the undescribed Cercozoa sp. strain M6MM. We supplemented these new data with the genomes of Mikrocytos mackini, and Paramikrocytos canceri. Using this dataset, we carried out a comprehensive phylogenomic analysis of Rhizaria and show that Ascetosporean genomes have undergone functional reduction, primarily in metabolic pathways, and expansions in gene families encoding proteases and transporters. Together, our results present important new genomic information from a lineage of enigmatic parasites, shedding new light on the free-living to parasite evolutionary transition in Rhizaria. Check it out here: Thorén MH, Onuț-Brännström I, Alfjorden A, Pecková H, Swords F, Hooper C, Holzer AS, Bass D, Burki F. 2024. Comparative genomics of Ascetosporea gives new insight into the evolutionary basis for animal parasitism in Rhizaria. BMC Biol. 22:103.  Fabien received a sabbatical grant from the Science Faculty (Uppsala University) for a 3-months visit–a minibatical?–to Patrick Keeling's lab at the University of British Columbia (UBC). Plenty of sampling trips in the pipeline and time in the lab. Very grateful for the opportunity!
Welcome to Matias Wanntorp, a 45hp MSc student in bioinformatics who will work on Picozoa phylogenomics!
Welcome to Xavi Florenza, a joint postdoc with the lab of Lars Behrendt who will work on targeting cell sorting microfluidics solution! Welcome both, we are excited to have you in the group. |
