title: Construction of a replicon and an infectious cDNA clone of the Sofjin strain of the Far-Eastern subtype of tick-borne encephalitis virus.
abstract: Tick-borne encephalitis virus (TBEV) causes severe encephalitis in humans. The Sofjin-HO strain is the prototype strain of the TBEV Far-Eastern subtype and is highly pathogenic in a mouse model. In this study, we constructed replicons and infectious cDNA clones of the Sofjin-HO strain. The replication of the replicon RNA was confirmed, and infectious viruses were recovered from the infectious cDNA clone. The recombinant viruses showed similar virulence characteristics to those of the parental virus. While characterizing the replicon and infectious cDNA, several amino acid differences derived from cell culture adaptations were analysed. The amino acids differences at E position 496 and NS4A position 58 were found to affect viral replication. The Gly- or Ala-to-Glu substitution at E position 122 was shown to increase neuroinvasiveness in mice. These replicons and infectious cDNA clones are useful in revealing the viral molecular determinants involved in the replication and pathogenicity of TBEV.
authors.affiliation: Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Takano
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yoshii
authors.forename: Yuki
authors.initials: Y
authors.lastname: Omori-Urabe
authors.forename: Kana
authors.initials: K
authors.lastname: Yokozawa
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kariwa
authors.forename: Ikuo
authors.initials: I
authors.lastname: Takashima
mesh_terms: D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism; D004669:Encephalitis Viruses, Tick-Borne / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity / Q000502:physiology; D004675:Encephalitis, Tick-Borne / Q000821:virology*; D005260:Female; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D012093:Replicon; D014774:Virulence; D014779:Virus Replication
chemical_list: D018076:DNA, Complementary; D004279:DNA, Viral