Construction of an infectious cDNA clone for Omsk hemorrhagic fever virus, and characterization of mutations in NS2A and NS5.
Omsk hemorrhagic fever virus (OHFV) is a member of the tick-borne encephalitis serocomplex of flaviviruses, and causes hemorrhagic disease in humans. In this study, an infectious cDNA of OHFV was constructed to investigate the molecular mechanisms involved in OHFV pathogenesis for the first time. Our cDNA clone was capable of producing infectious virus which is genetically identical to the parental Guriev strain, and the recombinant virus showed similar biological properties to the parental virus including growth kinetics and virulence characteristics. While characterizing the cDNAs, fortuitous mutations at NS2A position 46 and NS5 position 836 were found to affect viral production. By using a viral replicon expressing luciferase, it was shown that both of the mutations produced a defect in RNA replication and that the NS5 mutation induced a temperature-sensitive phenotype, indicating the importance of these residues in RNA replication. This infectious cDNA will be a useful tool to study the replication and pathogenesis of OHFV.
Yoshii
Kentaro
K
Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan. kyoshii@vetmed.hokudai.ac.jp
Igarashi
Manabu
M
Ito
Kimihito
K
Kariwa
Hiroaki
H
Holbrook
Michael R
MR
Takashima
Ikuo
I
D000818:Animals; D001835:Body Weight; D002478:Cells, Cultured; D006224:Cricetinae; D004252:DNA Mutational Analysis; D018076:DNA, Complementary / Q000235:genetics*; D004195:Disease Models, Animal; D004669:Encephalitis Viruses, Tick-Borne / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity* / Q000502:physiology*; D004675:Encephalitis, Tick-Borne / Q000473:pathology / Q000821:virology; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D020125:Mutation, Missense; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA; D016019:Survival Analysis; D019562:Viral Load; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000378:metabolism*; D014774:Virulence; D014779:Virus Replication
D018076:DNA, Complementary; D050505:Mutant Proteins; D012367:RNA, Viral; D017361:Viral Nonstructural Proteins