title: Polintons: a hotbed of eukaryotic virus, transposon and plasmid evolution.
abstract: Polintons (also known as Mavericks) are large DNA transposons that are widespread in the genomes of eukaryotes. We have recently shown that Polintons encode virus capsid proteins, which suggests that these transposons might form virions, at least under some conditions. In this Opinion article, we delineate the evolutionary relationships among bacterial tectiviruses, Polintons, adenoviruses, virophages, large and giant DNA viruses of eukaryotes of the proposed order 'Megavirales', and linear mitochondrial and cytoplasmic plasmids. We hypothesize that Polintons were the first group of eukaryotic double-stranded DNA viruses to evolve from bacteriophages and that they gave rise to most large DNA viruses of eukaryotes and various other selfish genetic elements.
authors.affiliation: Institut Pasteur, Unité Biologie Moléculaire du Gène chez les Extrêmophiles, Department of Microbiology, Paris 75015, France.
authors.forename: Mart
authors.initials: M
authors.lastname: Krupovic
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894, USA.
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Koonin
mesh_terms: D005075:Biological Evolution; D004251:DNA Transposable Elements / Q000235:genetics*; D004279:DNA, Viral / Q000235:genetics*; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D016679:Genome, Viral; D008958:Models, Molecular; D010957:Plasmids / Q000235:genetics*; D011487:Protein Conformation; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D014780:Viruses / Q000235:genetics*
chemical_list: D004251:DNA Transposable Elements; D004279:DNA, Viral; D014764:Viral Proteins