Article

Genetic characterization of a new insect flavivirus isolated from Culex pipiens mosquito in Japan.

Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
Virology (impact factor: 3.35). 04/2007; 359(2):405-14. DOI:10.1016/j.virol.2006.09.039 pp.405-14
Source: PubMed

ABSTRACT We found a new flavivirus that is widespread in Culex pipiens and other Culex mosquitoes in Japan. The virus isolate, named Culex flavivirus (CxFV), multiplied only in mosquito cell lines producing a moderate cytopathic effect, but did not grow in mammalian cells. The CxFV genome is single-stranded RNA, 10,834 nt in length and containing a single open reading frame encoding a polyprotein of 3362 aa with 5' and 3' untranslated regions (UTRs) of 91 and 657 nt, respectively. Phylogenetic analyses revealed that CxFV is closely related to the insect flaviviruses associated with Aedes mosquitoes, Cell fusing agent (CFA) and Kamiti River virus (KRV). The 3' UTR of CxFV contains four tandem repeats, which have sequence similarities to the two direct repeats in the CFA and KRV 3' UTRs. These results suggest that CxFV may be a new group of insect flaviviruses.

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Keywords

3' untranslated regions
 
Aedes mosquitoes
 
Cell fusing agent
 
Culex flavivirus
 
CxFV
 
CxFV genome
 
insect flaviviruses
 
Japan
 
KRV
 
KRV 3' UTRs
 
mammalian cells
 
moderate cytopathic effect
 
mosquito cell lines
 
new flavivirus
 
Phylogenetic analyses
 
sequence similarities
 
single open reading frame encoding
 
tandem