title: Temporal analysis of reassortment and molecular evolution of Cucumber mosaic virus: Extra clues from its segmented genome.
abstract: Cucumber mosaic virus (CMV) is a damaging pathogen of over 200 mono- and dicotyledonous crop species worldwide. It has the broadest known host range of any virus, but the timescale of its evolution is unknown. To investigate the evolutionary history of this virus, we obtained the genomic sequences of 40 CMV isolates from brassicas sampled in Iran, Turkey and Japan, and combined them with published sequences. Our synonymous ('silent') site analyses revealed that the present CMV population is the progeny of a single ancestor existing 1550-2600 years ago, but that the population mostly radiated 295-545 years ago. We found that the major CMV lineages are not phylogeographically confined, but that recombination and reassortment is restricted to local populations and that no reassortant lineage is more than 251 years old. Our results highlight the different evolutionary patterns seen among viral pathogens of brassica crops across the world.
authors.affiliation: Laboratory of Plant Virology, Faculty of Agriculture, Saga University, Saga, Japan; The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan. Electronic address: ohshimak@cc.saga-u.ac.jp.
authors.forename: Kazusato
authors.initials: K
authors.lastname: Ohshima
authors.affiliation: Laboratory of Plant Virology, Faculty of Agriculture, Saga University, Saga, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Matsumoto
authors.affiliation: Laboratory of Plant Virology, Faculty of Agriculture, Saga University, Saga, Japan; The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Yasaka
authors.affiliation: Laboratory of Plant Virology, Faculty of Agriculture, Saga University, Saga, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Nishiyama
authors.affiliation: Laboratory of Plant Virology, Faculty of Agriculture, Saga University, Saga, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Soejima
authors.affiliation: Department of Plant Protection, Faculty of Agriculture, University of Canakkale Onsekiz Mart, Canakkale, Turkey.
authors.forename: Savas
authors.initials: S
authors.lastname: Korkmaz
authors.affiliation: School of Biological Sciences, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Simon Y W
authors.initials: SY
authors.lastname: Ho
authors.affiliation: Emeritus Faculty, Australian National University, Canberra, Australia.
authors.forename: Adrian J
authors.initials: AJ
authors.lastname: Gibbs
authors.affiliation: Laboratory of Plant Pathology, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Takeshita
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D001937:Brassica / Q000821:virology*; D017799:Cucumovirus / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification; D019143:Evolution, Molecular; D005828:Genetics, Population; D016679:Genome, Viral / Q000235:genetics*; D007492:Iran; D007564:Japan; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology; D018515:Plant Leaves / Q000821:virology; D012367:RNA, Viral / Q000235:genetics; D016865:Reassortant Viruses / Q000235:genetics; D011995:Recombination, Genetic; D016415:Sequence Alignment; D017423:Sequence Analysis, RNA; D014421:Turkey
chemical_list: D012367:RNA, Viral
keywords: Cucumber mosaic virus; Cucumovirus; Evolution; Reassortment; Selection; Synonymous sites; Timescale