@article{PAR00010402,
  title = {{M}imiviridae : clusters of orthologous genes, reconstruction of gene repertoire evolution and proposed expansion of the giant virus family},
  author = {{Y}utin, {N}. and {C}olson, {P}. and {R}aoult, {D}idier and {K}oonin, {E}. {V}.},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground: {T}he family {M}imiviridae belongs to the large monophyletic group of {N}ucleo-{C}ytoplasmic {L}arge {DNA} {V}iruses ({NCLDV}; proposed order {M}egavirales) and encompasses giant viruses infecting amoeba and probably other unicellular eukaryotes. {T}he recent discovery of the {C}afeteria roenbergensis virus ({C}ro{V}), a distant relative of the prototype mimiviruses, led to a substantial expansion of the genetic variance within the family {M}imiviridae. {I}n the light of these findings, a reassessment of the relationships between the mimiviruses and other {NCLDV} and reconstruction of the evolution of giant virus genomes emerge as interesting and timely goals. {R}esults: {D}atabase searches for the protein sequences encoded in the genomes of several viruses originally classified as members of the family {P}hycodnaviridae, in particular {O}rganic {L}ake phycodnaviruses and {P}haeocystis globosa viruses ({OLPG}), revealed a greater number of highly similar homologs in members of the {M}imiviridae than in phycodnaviruses. {W}e constructed a collection of 898 {C}lusters of {O}rthologous {G}enes for the putative expanded family {M}imiviridae ({M}imi{COG}s) and used these clusters for a comprehensive phylogenetic analysis of the genes that are conserved in most of the {NCLDV}. {T}he topologies of the phylogenetic trees for these conserved viral genes strongly support the monophyly of the {OLPG} and the mimiviruses. {T}he same tree topology was obtained by analysis of the phyletic patterns of conserved viral genes. {W}e further employed the mimi{COG}s to obtain a maximum likelihood reconstruction of the history of genes losses and gains among the giant viruses. {T}he results reveal massive gene gain in the mimivirus branch and modest gene gain in the {OLPG} branch. {C}onclusions: {T}hese phylogenomic results reported here suggest a substantial expansion of the family {M}imiviridae. {T}he proposed expanded family encompasses a greater diversity of viruses including a group of viruses with much smaller genomes than those of the original members of the {M}imiviridae. {I}f the {OLPG} group is included in an expanded family {M}imiviridae, it becomes the only family of giant viruses currently shown to host virophages. {T}he mimi{COG}s are expected to become a key resource for phylogenomics of giant viruses.},
  keywords = {},
  booktitle = {},
  journal = {{V}irology {J}ournal},
  volume = {10},
  numero = {},
  pages = {106},
  ISSN = {1743-422{X}},
  year = {2013},
  DOI = {10.1186/1743-422x-10-106},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00010402},
}