College of Veterinary Medicine, Jilin University, Changchun, Jilin, China; Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, China.
Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, Jilin, China.
Virus Res. 2018 May 2;250:95-103. doi: 10.1016/j.virusres.2018.04.012. Epub 2018 Apr 22.
The family Circoviridae comprises a large group of small circular single-stranded DNA viruses with several members causing severe pig and poultry diseases. In recent years the number of new viruses within the family has had an explosive increase showing a high level of genetic diversity and a broad host range. In this report we describe two more circoviruses identified from bats in Yunnan and Heilongjiang provinces in China. Full genome sequencing has revealed that these bat associated circoviruses (bat ACV) should be classified as new species within the genus Circovirus based on the demarcation criteria of the International Committee on the Taxonomy of Viruses (ICTV). The most striking result is the novel finding of a 21-28 nt polythymidine (poly-T) tract in the 3' terminal intergenic region of bat ACV isolates from Heilongjiang province. To understand its role in viral replication, a wild type bat ACV and a mutated version with the entire poly-T deleted were rescued through construction of infectious clones. Replication comparison in vitro showed that the poly-T is not essential for viral replication. Identification of additional bat ACV isolates and study of their biological characteristics will be the main task in future to understand the potential roles of bats in transmission of circoviruses to terrestrial mammals and humans.
圆环病毒科包含一大组小型环状单链 DNA 病毒，其中一些成员可导致严重的猪和家禽疾病。近年来，该科内新病毒的数量呈爆炸式增长，表现出高度的遗传多样性和广泛的宿主范围。在本报告中，我们描述了在中国云南和黑龙江两省蝙蝠中发现的另外两种圆环病毒。全基因组测序表明，这些与蝙蝠相关的圆环病毒（bat ACV）应根据国际病毒分类委员会（ICTV）的划分标准，被归类为圆环病毒属中的新种。最引人注目的结果是，在黑龙江省蝙蝠 ACV 分离株的 3'末端基因间区发现了一个 21-28nt 的聚胸腺嘧啶（poly-T）序列。为了了解其在病毒复制中的作用，我们通过构建感染性克隆拯救了野生型 bat ACV 和一个完全缺失 poly-T 的突变体。体外复制比较表明，poly-T 对于病毒复制不是必需的。鉴定更多的蝙蝠 ACV 分离株并研究其生物学特性将是未来的主要任务，以便了解蝙蝠在圆环病毒向陆地哺乳动物和人类传播中的潜在作用。
