Molecular characterization of full-length genome of Japanese encephalitis virus isolated in Liaoning Province in 2008.

Abstract

To sequence and analyze the whole genome of Japanese encephalitis virus (JEV) isolated from mosquitoes in Liaoning province in 2008. Using RT-PCR to amplify fragments with genome sequencing primer. The full-length genome was obtained by sequencing and splicing. The differentiation analysis for nucleotides, deduced amino acid sequence and phylogenetic tree was performed by the software of Clustal X (1.83), ATGC (V4), DNAStar, GENEDOC (3.2) and Mega (4.0). The whole genome of strain LN0828 possesses 10 965 nucleotides. An open reading frame from 97 to 10 392 including 10 296 nucleotides is capable of coding for a 3432 amino acid polyprotein. Comparison of strain LN0828 genomic sequence with those of 32 JEV isolates in GenBank showed that nucleotide sequence divergence ranges from 1.6% to 16.4%, which resulted in amino acid sequence divergence from 0.3% to 5.1%. In comparison with live attenuated vaccine stain SA14-14-2 in open reading frame, strain LN0828 has a total of 1186 nucleotide substitutions, 86 amino acid divergences. Based on phylogenetic analysis, the strain LN0828 belongs to the genotype I JEV. The whole genome of strain LN0828 is close to those of isolates from Liaoning in 2002 and 2007, which were grouped into genotype I JEV.