‘‘Megavirales’’, a proposed new order for eukaryotic nucleocytoplasmic large DNA viruses

Authors

Philippe Colson, Aix-Marseille Universite
Xavier De Lamballerie, EHSP French School of Public Health, Aix-Marseille Universite
Natalya Yutin, National Institutes of Health
Sassan Asgari, The University of Queensland
Yves Bigot, International Committee on Taxonomy of Viruses
Dennis K. Bideshi, University of California
Xiao-Wen Cheng, Miami University
Brian A. Federici, University of California
James L. Van Etten, University of Nebraska-LincolnFollow
Eugene V. Koonin, National Institutes of Health
Bernard La Scola, Aix-Marseille Universite
Didier Raoult, Aix-Marseille Universite

ORCID IDs

James L. Van Etten

Document Type

Article

Date of this Version

2013

Citation

Arch Virol (2013) 158:2517–2521

Comments

This article is a U.S. government work, and is not subject to copyright in the United States.

Abstract

The nucleocytoplasmic large DNA viruses (NCLDVs) comprise a monophyletic group of viruses that infect animals and diverse unicellular eukaryotes. The NCLDV group includes the families Poxviridae, Asfarviridae, Iridoviridae, Ascoviridae, Phycodnaviridae, Mimiviridae and the proposed family ‘‘Marseilleviridae’’. The family Mimiviridae includes the largest known viruses, with genomes in excess of one megabase, whereas the genome size in the other NCLDV families varies from 100 to 400 kilobase pairs. Most of the NCLDVs replicate in the cytoplasm of infected cells, within so-called virus factories. The NCLDVs share a common ancient origin, as demonstrated by evolutionary reconstructions that trace approximately 50 genes encoding key proteins involved in viral replication and virion formation to the last common ancestor of all these viruses. Taken together, these characteristics lead us to propose assigning an official taxonomic rank to the NCLDVs as the order ‘‘Megavirales’’, in reference to the large size of the virions and genomes of these viruses.