Asgard archaea illuminate the origin of eukaryotic cellular complexity

  title={Asgard archaea illuminate the origin of eukaryotic cellular complexity},
  author={Katarzyna Zaremba-Niedźwiedzka and Eva F. Caceres and Jimmy H. W. Saw and Disa B{\"a}ckstr{\"o}m and Lina Juzokaite and Emmelien Vancaester and Kiley West Seitz and Karthik Anantharaman and Piotr Starnawski and Kasper U. Kjeldsen and Matthew B. Stott and Takuro Nunoura and Jillian F. Banfield and Andreas Schramm and Brett J. Baker and Anja Spang and Thijs J. G. Ettema},
The origin and cellular complexity of eukaryotes represent a major enigma in biology. Current data support scenarios in which an archaeal host cell and an alphaproteobacterial (mitochondrial) endosymbiont merged together, resulting in the first eukaryotic cell. The host cell is related to Lokiarchaeota, an archaeal phylum with many eukaryotic features. The emergence of the structural complexity that characterizes eukaryotic cells remains unclear. Here we describe the ‘Asgard’ superphylum, a… 

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Metabolic analysis indicates an autotrophic lifestyle of this hot spring archaeon with a complete tetrahydromethanopterin Wood-Ljungdahl pathway for carbon dioxide reduction and an arsenic efflux detoxification, and posit that all the key components of the eukaryotic endosomal system might have evolved from a common ancestor of Asgard archaea and eUKaryotes.

Coevolution of Eukaryote-like Vps4 and ESCRT-III Subunits in the Asgard Archaea

Evidence is provided that the ESCRT complexes from Asgard archaea and eukaryotes are evolutionarily related and functionally similar, suggesting that despite the apparent absence of endomembranes in archaea, Eukaryotic ESCRT was inherited from an Asgard archaeal ancestor, alongside the emergence of endOMembrane system during eUKaryogenesis.

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Reconciling Asgardarchaeota Phylogenetic Proximity to Eukaryotes and Planctomycetes Cellular Features in the Evolution of Life

  • D. Devos
  • Biology
    Molecular biology and evolution
  • 2021
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Genomes of Asgard archaea encode profilins that regulate actin

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Proposal of the reverse flow model for the origin of the eukaryotic cell based on comparative analyses of Asgard archaeal metabolism

The ‘reverse flow model’ is proposed, an updated symbiogenetic model for the origin of eukaryotes that involves electron or hydrogen flow from an organoheterotrophic archaeal host to a bacterial symbiont.

Isolation of an archaeon at the prokaryote–eukaryote interface

A hypothetical model for eukaryogenesis is proposed, termed the entangle–engulf–endogenize (also known as E 3 ) model, and isolation and characterization of an Asgard archaeon related to Lokiarchaeota reveals insights into how eukARYotes may have evolved from prokaryotes.



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A new model is proposed, the 'PhAT (phagocytosing archaeon theory)', which explains the emergence of the cellular and genomic features of eukaryotes in the light of a transiently complex phagocyrifying archaeon.

Origin of eukaryotes from within archaea, archaeal eukaryome and bursts of gene gain: eukaryogenesis just made easier?

  • E. Koonin
  • Biology
    Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2015
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A phylogenomics approach is used to reevaluate the evolutionary affiliation between Archaea and eukaryotes, and provides further support for scenarios in which the nuclear lineage in eUKaryotes emerged from within the archaeal radiation, displaying a strong phylogenetic affiliation with, or even within, the Archaeal TACK superphylum.

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These exciting new metagenomic studies are looked at, what they say about archaeal physiology in modern environments, how they impact views on host‐mitochondrion physiological interactions at eukaryote origin, and how to understand how these new lineages live in their environment is important.