An Alternative Root for the Eukaryote Tree of Life
2014 (English)In: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 24, no 4, 465-470 p.Article in journal (Refereed) Published
The root of the eukaryote tree of life defines some of the most fundamental relationships among species. It is also critical for defining the last eukaryote common ancestor (LECA), the shared heritage of all extant species. The unikont-bikont root has been the reigning paradigm for eukaryotes for more than 10 years but is becoming increasingly controversial. We developed a carefully vetted data set, consisting of 37 nuclear-encoded proteins of close bacterial ancestry (euBacs) and their closest bacterial relatives, augmented by deep sequencing of the Acrasis kona (Heterolobosea, Discoba) transcriptome. Phylogenetic analysis of these data produces a highly robust, fully resolved global phy- logeny of eukaryotes. The tree sorts all examined eukaryotes into three megagroups and identifies the Discoba, and potentially its parent taxon Excavata, as the sister group to the bulk of known eukaryote diversity, the proposed Neozoa (Amorphea + Stramenopila+Alveolata+Rhizaria+ Plantae [SARP]). All major alternative hypotheses are rejected with as little as w50% of the data, and this resolu- tion is unaffected by the presence of fast-evolving alignment positions or distant outgroup sequences. This ‘‘neozoan- excavate’’ root revises hypotheses of early eukaryote evolution and highlights the importance of the poorly stud- ied Discoba for understanding the evolution of eukaryotic diversity and basic cellular processes.
Place, publisher, year, edition, pages
2014. Vol. 24, no 4, 465-470 p.
Eukaryote root, molecular phylogenetics, phylogenetics
Biological Systematics Evolutionary Biology Bioinformatics (Computational Biology)
Research subject Biology with specialization in Evolutionary Organismal Biology; Biology with specialization in Molecular Evolution; Biology with specialization in Systematics
IdentifiersURN: urn:nbn:se:uu:diva-218740DOI: 10.1016/j.cub.2014.01.036ISI: 000331718900032OAI: oai:DiVA.org:uu-218740DiVA: diva2:696886
FunderSwedish Research Council