Nuclear genome sequence of the plastid-lacking cryptomonad Goniomonas avonlea provides insights into the evolution of secondary plastids

Ugo Cenci (1, 2) , Shannon Sibbald (1, 2) , Bruce Curtis (1, 2) , Ryoma Kamikawa (3) , Laura Eme (1, 2) , Daniel Moog (1, 2) , Bernard Henrissat (4, 5) , Eric Marechal (6) , Malika Chabi (7) , Christophe Djemiel (7) , Andrew Roger (1, 2, 8) , Eunsoo Kim (9) , John Archibald (1, 2, 8)

1 Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
2 Center for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University
3 Graduate School of Human and Environmental Studies
4 AFMB - Architecture et fonction des macromolécules biologiques
5 King Abdulaziz University
6 LPCV - Physiologie cellulaire et végétale
7 UGSF - Unité de Glycobiologie Structurale et Fonctionnelle - UMR 8576
8 CIFAR - Canadian Institute for Advanced Research
9 Division of Invertebrate Zoology, American Museum of Natural History [New York, USA]

The evolution of photosynthesis has been a major driver in eukaryotic diversification. Eukaryotes have acquired plastids (chloroplasts) either directly via the engulfment and integration of a photosynthetic cyanobacterium (primary endosymbiosis) or indirectly by engulfing a photosynthetic eukaryote (secondary or tertiary endosymbiosis). The timing and frequency of secondary endosymbiosis during eukaryotic evolution is currently unclear but may be resolved in part by studying cryptomonads, a group of single-celled eukaryotes comprised of both photosynthetic and non-photosynthetic species. While cryptomonads such as Guillardia theta harbor a red algal-derived plastid of secondary endosymbiotic origin, members of the sister group Goniomonadea lack plastids. Here, we present the genome of Goniomonas avonlea-the first for any goniomonad-to address whether Goniomonadea are ancestrally non-photosynthetic or whether they lost a plastid secondarily.

Mots clés: Cryptomonads; Cryptophytes; Genome evolution; Phylogenomics; Secondary endosymbiosis; Goniomonad; Goniomonas avonlea; Photosynthesis evolution; Metabolic pathways

Domaines: Biochimie, Biologie Moléculaire

Ugo Cenci, Shannon Sibbald, Bruce Curtis, Ryoma Kamikawa, Laura Eme, et al.. Nuclear genome sequence of the plastid-lacking cryptomonad Goniomonas avonlea provides insights into the evolution of secondary plastids. BMC Biology, 2018, 16 (1), pp.137. ⟨10.1186/s12915-018-0593-5⟩. ⟨hal-02046523⟩