title: Cell type-dependent RNA recombination frequency in the Japanese encephalitis virus.
abstract: Japanese encephalitis virus (JEV) is one of approximately 70 flaviviruses, frequently causing symptoms involving the central nervous system. Mutations of its genomic RNA frequently occur during viral replication, which is believed to be a force contributing to viral evolution. Nevertheless, accumulating evidences show that some JEV strains may have actually arisen from RNA recombination between genetically different populations of the virus. We have demonstrated that RNA recombination in JEV occurs unequally in different cell types. In the present study, viral RNA fragments transfected into as well as viral RNAs synthesized in mosquito cells were shown not to be stable, especially in the early phase of infection possibly via cleavage by exoribonuclease. Such cleaved small RNA fragments may be further degraded through an RNA interference pathway triggered by viral double-stranded RNA during replication in mosquito cells, resulting in a lower frequency of RNA recombination in mosquito cells compared to that which occurs in mammalian cells. In fact, adjustment of viral RNA to an appropriately lower level in mosquito cells prevents overgrowth of the virus and is beneficial for cells to survive the infection. Our findings may also account for the slower evolution of arboviruses as reported previously.
authors.affiliation: Division of Microbiology, Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Chiang
authors.affiliation: Division of Microbiology, Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan ; Department of Plant Pathology, University of Kentucky, Lexington, KY 40546-0312, USA.
authors.forename: Ching-Kai
authors.initials: CK
authors.lastname: Chuang
authors.affiliation: Division of Microbiology, Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan ; Department of Microbiology and Immunology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
authors.forename: Mei
authors.initials: M
authors.lastname: Chao
authors.affiliation: Division of Microbiology, Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan ; Department of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
authors.forename: Wei-June
authors.identifier: 0000-0002-2153-1893
authors.initials: WJ
authors.lastname: Chen
mesh_terms: D000818:Animals; D002490:Central Nervous System / Q000503:physiopathology / Q000821:virology*; D009033:Culicidae / Q000821:virology; D004664:Encephalitis Virus, Japanese / Q000235:genetics* / Q000472:pathogenicity; D004672:Encephalitis, Japanese / Q000235:genetics* / Q000473:pathology / Q000635:transmission / Q000821:virology; D006801:Humans; D012367:RNA, Viral / Q000235:genetics; D011995:Recombination, Genetic; D014779:Virus Replication
chemical_list: D012367:RNA, Viral