title: The Big Bang of picorna-like virus evolution antedates the radiation of eukaryotic supergroups.
abstract: The recent discovery of RNA viruses in diverse unicellular eukaryotes and developments in evolutionary genomics have provided the means for addressing the origin of eukaryotic RNA viruses. The phylogenetic analyses of RNA polymerases and helicases presented in this Analysis article reveal close evolutionary relationships between RNA viruses infecting hosts from the Chromalveolate and Excavate supergroups and distinct families of picorna-like viruses of plants and animals. Thus, diversification of picorna-like viruses probably occurred in a 'Big Bang' concomitant with key events of eukaryogenesis. The origins of the conserved genes of picorna-like viruses are traced to likely ancestors including bacterial group II retroelements, the family of HtrA proteases and DNA bacteriophages.
authors.affiliation: National Center for Biotechnology Information, National Institutes of Health, Bethesda, Maryland 20894, USA.
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Koonin
authors.forename: Yuri I
authors.initials: YI
authors.lastname: Wolf
authors.forename: Keizo
authors.initials: K
authors.lastname: Nagasaki
authors.forename: Valerian V
authors.initials: VV
authors.lastname: Dolja
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005057:Eukaryotic Cells / Q000821:virology; D016679:Genome, Viral; D054884:Host-Pathogen Interactions / Q000235:genetics; D008954:Models, Biological; D010802:Phylogeny; D010849:Picornaviridae / Q000145:classification* / Q000201:enzymology / Q000235:genetics*; D020365:RNA Helicases / Q000235:genetics; D012194:RNA-Directed DNA Polymerase / Q000235:genetics
chemical_list: D012194:RNA-Directed DNA Polymerase; D020365:RNA Helicases