Genome Analysis of a Novel Tembusu Virus in Taiwan

• Published in: Viruses 2020-05, Vol.12 (5), p.567
• Main Authors: Peng, Shih-Huan, Su, Chien-Ling, Chang, Mei-Chun, Hu, Huai-Chin, Yang, Su-Lin, Shu, Pei-Yun
• Format: Article
• Language: English
• Subjects: 3' Untranslated regions; Animals; Base Sequence; Cell culture; Cell Line; Chickens; Chlorocebus aethiops; Culicidae - virology; Deoxyribonucleic acid; DNA; Encephalitis; Fibroblasts; Flavivirus - classification; Flavivirus - genetics; Flavivirus - growth & development; Flavivirus - isolation & purification; flavivirus 3′-UTR variable region; Flavivirus Infections - veterinary; Flavivirus Infections - virology; Flaviviruses; Genetic aspects; Genome, Viral; Genomes; Host range; Host Specificity; Kinetics; Mosquitoes; Nucleotide sequence; Open Reading Frames; Phylogeny; Polyproteins - genetics; Poultry Diseases - virology; Ribonucleic acid; RNA; Sitiawan virus; Taiwan; Tembusu virus; Variable region; Vero Cells; Virulence; Viruses; Wetlands; Whole Genome Sequencing
• ISSN: 1999-4915; 1999-4915
• DOI: 10.3390/v12050567

We identified and isolated a novel Tembusu virus (TMUV) strain TP1906 (TMUV-TP1906) from a mosquito pool collected from the northern part of Taiwan in 2019. The TMUV-TP1906 genome is a 10,990-nucleotide-long, positive-sense, single-stranded RNA, consisting of a single open reading frame (ORF) encoding a polyprotein of 3425 amino acids, with 5' and 3' untranslated regions (UTRs) of 94 and 618 nucleotides, respectively. The nucleotide sequence of the TMUV-TP1906 of ORF exhibited 93.71% and 91.27% similarity with Sitiawan virus (STWV) and the TMUV prototype strain MM1775, respectively. The 3'-UTR variable region of TMUV-TP1906 showed nucleotide sequence divergence with other TMUV strains. Phylogenetic analysis of the complete ORF and polyprotein sequences revealed that TMUV-TP1906 is most closely related to STWV which causes encephalitis and retarded growth in chickens. We found that the TMUV-TP1906 caused a cytopathic effect (CPE) in the DF-1 chicken fibroblast cell line, while no apparent CPE was observed in Vero and C6/36 cells. In this study, we first identified and isolated a novel TMUV strain in Taiwan. In addition, to our knowledge, it is the first time that the TMUV strain was isolated from the mosquitoes. Further study is warranted to investigate the host range and virulence of TMUV-TP1906.