Mythical origins of the actin cytoskeleton

Curr Opin Cell Biol. 2021 Feb:68:55-63. doi: 10.1016/j.ceb.2020.08.011. Epub 2020 Oct 10.

Abstract

The origin of the eukaryotic cell is one of the greatest mysteries in modern biology. Eukaryotic-wide specific biological processes arose in the lost ancestors of eukaryotes. These distinctive features, such as the actin cytoskeleton, define what it is to be a eukaryote. Recent sequencing, characterization, and isolation of Asgard archaea have opened an intriguing window into the pre-eukaryotic cell. Firstly, sequencing of anaerobic sediments identified a group of uncultured organisms, Asgard archaea, which contain genes with homology to eukaryotic signature genes. Secondly, characterization of the products of these genes at the protein level demonstrated that Asgard archaea have related biological processes to eukaryotes. Finally, the isolation of an Asgard archaeon has produced a model organism in which the morphological consequences of the eukaryotic-like processes can be studied. Here, we consider the consequences for the Asgard actin cytoskeleton and for the evolution of a regulated actin system in the archaea-to-eukaryotic transition.

Keywords: Actin cytoskeleton; Asgard archaea.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Actin Cytoskeleton / chemistry
  • Actin Cytoskeleton / genetics*
  • Actin Cytoskeleton / physiology
  • Actins / chemistry
  • Actins / genetics
  • Animals
  • Archaea / chemistry
  • Archaea / cytology*
  • Archaea / genetics
  • Archaea / isolation & purification
  • Archaeal Proteins / chemistry
  • Archaeal Proteins / genetics*
  • Archaeal Proteins / physiology
  • Biological Evolution*
  • Eukaryota / cytology
  • Eukaryota / genetics
  • Eukaryota / metabolism
  • Eukaryotic Cells / chemistry
  • Eukaryotic Cells / cytology*
  • Eukaryotic Cells / physiology
  • Humans
  • Metagenomics
  • Phylogeny
  • Sequence Analysis, Protein

Substances

  • Actins
  • Archaeal Proteins