PT  - JOURNAL ARTICLE
AU  - Yang Liu
AU  - Kira S. Makarova
AU  - Wen-Cong Huang
AU  - Yuri I. Wolf
AU  - Anastasia Nikolskaya
AU  - Xinxu Zhang
AU  - Mingwei Cai
AU  - Cui-Jing Zhang
AU  - Wei Xu
AU  - Zhuhua Luo
AU  - Lei Cheng
AU  - Eugene V. Koonin
AU  - Meng Li
TI  - Expanding diversity of Asgard archaea and the elusive ancestry of eukaryotes
AID  - 10.1101/2020.10.19.343400
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.10.19.343400
4099  - http://biorxiv.org/content/early/2020/10/20/2020.10.19.343400.short
4100  - http://biorxiv.org/content/early/2020/10/20/2020.10.19.343400.full
AB  - Comparative analysis of 162 (nearly) complete genomes of Asgard archaea, including 75 not reported previously, substantially expands the phylogenetic and metabolic diversity of the Asgard superphylum, with six additional phyla proposed. Phylogenetic analysis does not strongly support origin of eukaryotes from within Asgard, leaning instead towards a three-domain topology, with eukaryotes branching outside archaea. Comprehensive protein domain analysis in the 162 Asgard genomes results in a major expansion of the set of eukaryote signature proteins (ESPs). The Asgard ESPs show variable phyletic distributions and domain architectures, suggestive of dynamic evolution via horizontal gene transfer (HGT), gene loss, gene duplication and domain shuffling. The results appear best compatible with the origin of the conserved core of eukaryote genes from an unknown ancestral lineage deep within or outside the extant archaeal diversity. Such hypothetical ancestors would accumulate components of the mobile archaeal ‘eukaryome’ via extensive HGT, eventually, giving rise to eukaryote-like cells.Competing Interest StatementThe authors have declared no competing interest.