新疆乌拉尔田鼠细环病毒的分析与鉴定

Characterization and Identification of the Torque Teno Virus in Ural Field Mice in Xinjiang Province,China

啮齿动物是当前种类最多和分布最广的哺乳动物,也是重要的人兽共患病原自然宿主之一。新疆作为我国畜牧业大省,啮齿动物种类繁多,鼠害不仅严重破坏该地区牧场,其携带的病毒也对人类健康造成了潜在威胁。掌握新疆啮齿动物携带未知病毒的种类,为防范啮齿动物源人兽共患病提供参考依据。对采集自新疆阿克苏市的12只乌拉尔田鼠的心、肝、脾、肺、肾等脏器进行病毒宏基因组学分析,根据其结果对细环病毒进行了PCR检测和全基因分析。从6只(50%)乌拉尔田鼠的不同脏器中检测到了细环病毒,包括两个基因型(A1和A2),全长为2 220~2 232nt,编码四个开放阅读框。遗传分析发现该病毒开放阅读框1与英国啮齿动物细环病毒1型同源性最高,为80%,而与其它已知指环病毒同源性低于42.3%。依据国际病毒分类委员会新种判断标准,本研究发现的病毒和啮齿动物细环病毒1型同为该病毒科的一个新种,且属于不同的两个亚种,本研究为了解细环病毒自然多样性和进化动态提供了基础数据。

Rodents are widely distributed and diverse mammals. They are also one of the most important natural hosts of many zoonotic agents. Xinjiang Province （XP） in China has well-developed animal hus- bandry. It also offers a great variety of rodents, which seriously damage grassland and pose a conceivable threat to human＇ health by carrying rodent-borne viruses. We wished to survey the unknown viral patho- gens carried by rodents in XP and to present basic reference data for the prevention of potential rodent-as- sociated zoonoses. Twelve Ural field mice were sampled in Akesu, XP, and were subjected to viral met- agenomic analyses. A specific polymerase chain reaction was used to detect the torque teno virus （TTV） found by viral metagenomics in these samples. The full genome of the TTV was amplified and compared with known TTVs. In general, 6 of the 12 （50%） Ural field mice were positive for the TTV, the full ge- nome of which contained 2,220-2,232 nucleotides （nt） and could encode four open-reading frames （ORFs）. Phylogenetic analyses of ORF1 showed that viruses found there could be grouped into two clades （A1 and A2） and shared the highest 80% nt identities with previously reported rodent torque teno virus 1 （RoTTV1）, but showed 〈42.3% nt identities with other known anelloviruses. According to International Committee on Taxonomy of Viruses criteria （i. e. , the divergence of the ORF1 nucleotide sequence shares 20-35% within subspecies）, the virus identified Akesu could be a novel species along with RoTTV1, and should be a eandidate of different subspecies. These findings provide fundamental data to understand the natural diversity and evolutionary dynamics of the TTV.