Isolation and coding region sequence of Japanese encephalitis virus from Culex tritaeniorhynchus in Shuangjiang County, Yunnan Province
- Author:
GU Yangyang
;
HE Yuwen
;
RUAN Fangchao
- Publication Type:Journal Article
- Keywords:
GⅠa Japanese encephalitis virus;
whole genome;
phylogenetic analysis;
E protein structure prediction
- From:
China Tropical Medicine
2025;25(1):22-
- CountryChina
- Language:Chinese
-
Abstract:
BHK-21 cells, cytopathic effects (CPE) were detected, and flavivirus primers were amplified as positive. After the complete sequence of the virus was determined and spliced, a 10 840 nucleotide long sequence was obtained, encoding 3 432 amino acids. Phylogenetic analysis based on the whole gene sequence and E gene sequence showed that: The newly isolated SJM23-22 was most closely related to the GⅠa strain (C081) in Cambodia, with 98.5% nucleotide homology and 99.8% amino acid homology, while the homology with other genotypes was below 90% for nucleotides and below 98% for amino acids. The results of site analysis revealed 22 amino acid difference sites on the E gene compared to the live attenuated vaccine strain SA14-14-2, with 7 differences at 8 neurovirulence-related key amino acid sites. The results of important epitopes analysis indicated an exact match in three important epitopes in domain Ⅲ between the Shuangjiang isolates and the live attenuated vaccine strains. The results of secondary structure and tertiary structure prediction showed that the strain was characterized by random curling. Conclusions One strain of GⅠa-type JEV was isolated from Culex tritaeniorhynchus in Shuangjiang County, with no significant changes in the key amino acid sites related to antigenic epitopes. This study enriches the virus-carrying situation of Culex tritaeniorhynchus in Shuangjiang County, Yunnan Province, providing a reference for the prevention and control of the insect-borne epidemic in the province.Objective To investigate the status and molecular characteristics of Japanese encephalitis virus (JEV) carried by mosquitoes in Shuangjiang County, Lincang City, Yunnan Province. Methods Mosquito specimens were collected from cattle pens using mosquito traps in Shuangjiang County, Lincang City in August 2023. After mosquito species identification, BHK-21 cells and C6/36 cells were used in one group of 25 mosquitoes each. Positive isolates were identified by flavivirus primers. Subsequently, the full-length GⅠ-type JEV was amplified using 15 pairs of primers with RT-PCR, sequenced, and spliced, and sequence analysis was performed using bioinformatics software such as MEGA X, DNAstar, GeneDoc, SOPMA, and SWISS-MODEL. Results A total of 1 300 Culex tritaeniorhynchus were collected and divided into 52 groups for virus isolation, leading to the identification of one positive isolate (SJM23-22). After inoculation with C6/36 and
- Full text:20251113165404529614.Isolation and coding region sequence of Japanese encephalitis virus from Culex tritaeniorhynchus in Shuangjiang County, Yunnan Province.pdf
