title: Sputnik, a virophage infecting the viral domain of life.
abstract: This chapter discusses the astonishing discovery of the Sputnik virophage, a new virus infecting giant viruses of the genera Mimivirus and Mamavirus. While other virophages have also since been described, this chapter focuses mainly on Sputnik, which is the best described. We detail the general properties of the virophage life cycle, as well as its hosts, genomic characteristics, ecology, and origin. In addition to genetic, phylogenetic, and structural evidence, the existence of virophages has deeply altered our view of the tripartite division of life to include the addition of a fourth domain constituted of the nucleocytoplasmic large DNA viruses, an important point that is discussed.
authors.affiliation: URMITE, Centre National de la Recherche Scientifique UMR IRD 6236, Faculté de Médecine, Aix-Marseille Université, Marseille, France.
authors.forename: Christelle
authors.initials: C
authors.lastname: Desnues
authors.forename: Mickaël
authors.initials: M
authors.lastname: Boyer
authors.forename: Didier
authors.initials: D
authors.lastname: Raoult
mesh_terms: D000048:Acanthamoeba / Q000821:virology*; D000818:Animals; D004267:DNA Viruses / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure; D004279:DNA, Viral; D015870:Gene Expression; D016679:Genome, Viral; D056686:Mimiviridae / Q000235:genetics / Q000502:physiology / Q000648:ultrastructure; D010802:Phylogeny; D014764:Viral Proteins / Q000235:genetics; D014771:Virion / Q000235:genetics / Q000502:physiology / Q000648:ultrastructure; D053586:Virus Internalization; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D014764:Viral Proteins