Evolutionary history of the Coccolithoviridae.
We recently determined the genome sequence of the Coccolithoviridae strain Emiliania huxleyi virus 86 (EhV-86), a giant double-stranded DNA (dsDNA) algal virus from the family Phycodnaviridae that infects the marine coccolithophorid E. huxleyi. Here, we determine the phylogenetic relationship between EhV-86 and other large dsDNA viruses. Twenty-five core genes common to nuclear-cytoplasmic large dsDNA virus genomes were identified in the EhV-86 genome; sequence from eight of these genes were used to create a phylogenetic tree in which EhV-86 was placed firmly with the two other members of the Phycodnaviridae. We have also identified a 100-kb region of the EhV-86 genome which appears to have transferred into this genome from an unknown source. Furthermore, the presence of six RNA polymerase subunits (unique among the Phycodnaviridae) suggests both a unique evolutionary history and a unique lifestyle for this intriguing virus.
Allen
Michael J
MJ
Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, United Kingdom.
Schroeder
Declan C
DC
Holden
Matthew T G
MT
Wilson
William H
WH
D016000:Cluster Analysis; D019295:Computational Biology; D056890:Eukaryota / Q000821:virology*; D019143:Evolution, Molecular; D016679:Genome, Viral / Q000235:genetics*; D017862:Phycodnaviridae / Q000235:genetics*; D010802:Phylogeny