Full genome characterization and evolutionary analysis of Banna virus isolated from Culicoides, mosquitoes and ticks in Yunnan, China

Zhenxing Yang; Yuwen He; Yiju Chen; Jinxin Meng; Nan Li; Susheng Li; Jinglin Wang

doi:10.3389/fcimb.2023.1283580

Full genome characterization and evolutionary analysis of Banna virus isolated from Culicoides, mosquitoes and ticks in Yunnan, China

Front Cell Infect Microbiol. 2023 Nov 16:13:1283580. doi: 10.3389/fcimb.2023.1283580. eCollection 2023.

Authors

Zhenxing Yang^#¹, Yuwen He^#¹, Yiju Chen^{1

2}, Jinxin Meng¹, Nan Li¹, Susheng Li¹, Jinglin Wang¹

Affiliations

¹ Yunnan Tropical and Subtropical Animal Viral Disease Laboratory, Key Laboratory of Transboundary Animal Diseases Prevention and Control (Co-construction by Ministry and Province), Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, China.
² School of Public Health, Kunming Medical University, Kunming, Yunnan, China.

^# Contributed equally.

Abstract

Introduction: Banna virus (BAV), a potential pathogen that may cause human encephalitis, is the prototype species of genus Seadornaviru within the family Reoviridae, and has been isolated from a variety of blood-sucking insects and mammals in Asia.

Methods: Culicoides, Mosquitoes, and Ticks were collected overnight in Yunnan, China, during 2016-2023 using light traps. Virus was isolated from these collected blood-sucking insects and grown using Aedes albopictus (C6/36) cells. Preliminary identification of the virus was performed by agarose gel electrophoresis (AGE). The full genome sequences of the BAVs were determined by full-length amplification of cDNAs (FLAC) and sequenced using next-generation sequencing.

Results: In this study, 13 strains BAV were isolated from Culicoides, Mosquitoes and Ticks. Their viral genome consisted of 12 segments of double-stranded RNA (dsRNA), and with three distinct distribution patterns. Sequence analysis showed that Seg-5 of four strains (SJ_M46, SJ_M49, JC_M19-13 and JC_C24-13) has 435 bases nucleotide sequence insertions in their ORF compared to other BAVs, resulting in the length of Seg-5 up to 2128 nt. There are 34 bases sequence deletion in Seg-9 of 3 strains (WS_T06, MS_M166 and MS_M140). Comparison of the coding sequences of VP1, VP2, VP5, VP9 and VP12 of the 13 BAV strains, the results show that VP1, VP2 and VP12 are characterised by high levels of sequence conservation, while VP9 is highly variable, under great pressure to adapt and may be correlated with serotype. While also variable, VP5 appears to be under less adaptive pressure than VP9. Additionally, phylogenetic analysis indicates that the 13 BAV strains locate in the same evolutionary cluster as BAVs isolated from various blood-sucking insects, and are clustered according to geographical distribution.

Conclusion: The data obtained herein would be beneficial for the surveillance of evolutionary characteristics of BAV in China and neighboring countries as well as extend the knowledge about its genomic diversity and geographic distribution.

Keywords: Banna virus; China; Culicoides; full genome; mosquitoes; phylogenetic analysis; ticks.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aedes* / genetics
Animals
Ceratopogonidae* / genetics
China
Coltivirus* / genetics
Genome, Viral
Mammals / genetics
Phylogeny
Ticks* / genetics

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was funded by National Key Research and Development Program of China (2022YFC2601603); National Natural Science Foundation of China (32260896); Basic Research Projects of Yunnan Province (202201AS070062); Projects funded by the central government to guide local scientific and Technological Development (202207AB110006); Open Research Fund of Chinese Academy of Sciences (2022SPCAS001). Science and Technology Talents and Platform Plan of Yunnan Province Science and Technology Department (202305AO350020).