■版纳病毒(BAV),一种可能导致人类脑炎的潜在病原体,是Reoviridae家族中Seadornaviru属的原型物种,并已从亚洲的各种吸血昆虫和哺乳动物中分离出来。
■Culicoides,蚊子,在云南一夜之间收集了蜱虫,中国,在2016-2023年期间使用光陷阱。从这些收集的吸血昆虫中分离出病毒,并使用白纹伊蚊(C6/36)细胞进行培养。通过琼脂糖凝胶电泳(AGE)进行病毒的初步鉴定。通过cDNA的全长扩增(FLAC)确定BAV的全基因组序列,并使用下一代测序进行测序。
■在这项研究中,从Culicoides中分离出13株BAV,蚊子和蜱。他们的病毒基因组由12个双链RNA(dsRNA)片段组成,并有三种不同的分布模式。序列分析表明,与其他BAV相比,四个菌株(SJ_M46,SJ_M49,JC_M19-13和JC_C24-13)的Seg-5在其ORF中有435个碱基的核苷酸序列插入,导致Seg-5的长度高达2128nt。3株(WS_T06、MS_M166和MS_M140)的Seg-9中存在34个碱基序列缺失。比较13株BAV株VP1、VP2、VP5、VP9和VP12的编码序列,结果表明,VP1,VP2和VP12具有高水平的序列保守性,虽然VP9是高度可变的,适应压力大,可能与血清型相关。虽然也是可变的,VP5似乎处于比VP9更小的自适应压力下。此外,系统发育分析表明,这13株BAV与从各种吸血昆虫中分离的BAV位于同一进化簇,并根据地理分布进行聚类。
■本文获得的数据将有利于监测中国和周边国家的BAV的进化特征,并扩展有关其基因组多样性和地理分布的知识。
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.
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.
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.
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.