天山北麓中段主要湿地环境的病毒宏基因组学研究

The northern Tianshan Mountain is the area with the most developed economy and most concentrated population in Xinjiang, also is the important channel of wild bird migration, every year, a lot of wild birds migrate along the north side of Tianshan Mountains east-west back and forth. Some wild birds are the natural reservoir host for the viruses, and the viruses could pollute the habitat wetlands through the fecal, eating and drinking of the wild birds. This project will carry out the viral metagenomic analysis of the main wetlands in the middle part of northern Tianshan Mountain. The contents as follows: In the migratory seasons (spring and autumn) as well as the non-migratory season summer, the wild bird fecal and water samples from the wetlands including Chaiwopu Lake, Manas River watershed, Anjihai Reservoir, Kuytun River watershed and Ebinur Lake will be collected respectively; the nucleic acid will be extracted from the samples after filtration and concentration respectively, then reverse transcription and PCR amplification with random primers; the virus diversity and genetic variation will be investigated by viral metagenomic analysis and bioinformatics analysis of the PCR amplification products; to investigate the source and the dynamic change of the viruses in the wetlands, the change of virus species and abundance with time and space dimensions, as well as difference of virus species and abundance between fecal and water will be analyzed; finally, the pathogenic virus will be detected and confirmed by PCR and serological method. This project plant to reveal the virus source, diversity and dynamic change of the main wetlands in the middle part of northern Tianshan Mountain by virus community genomics, and then analyze the potential risk for the pathogenic virus transmission through the wetlands, finally provide the reference for the protection and management of the wetlands.

天山北麓是新疆经济最发达和人口最集中的地区，也是野鸟迁徙的重要通道，每年大量野鸟沿天山北麓湿地东西向来回迁徙。野鸟是一些病毒的自然储藏宿主，其携载的病毒可通过粪便和饮食等污染湿地。项目拟对天山北麓中段主要湿地环境进行病毒宏基因组学分析，内容包括：野鸟迁徙的春、秋季以及非迁徙的夏季采集柴窝堡湖、玛纳斯河流域、安集海水库、奎屯河流域和艾比湖等湿地环境中野鸟粪便和水样，样品过滤和浓缩后提取核酸并进行反转录和随机PCR扩增；利用病毒宏基因组学和生物信息学分析湿地环境病毒的种类、丰度和遗传变异及其随时空维度的变化，探讨湿地环境病毒的来源和动态变化；最后用PCR和血清学方法检测和确认致病性病毒。项目将从病毒群落基因组分析入手探讨湿地环境中病毒的来源、多样性和动态变化，分析致病性病毒通过湿地传播的潜在风险，为该区湿地的保护和管理提供参考。

本项目对天山北麓中段主要湿地水样和野鸟粪便样品以及周边活禽市场样品和啮齿类动物样品进行宏基因组学分析，探讨该区域湿地及周边环境细菌和病毒的多样性及其来源，并对检测到的部分致病性病毒进行分离和鉴定。主要结果和结论包括：1.天山北麓中段不同水库菌群组成存在差异，其与水源周边环境和人类活动等因素相关。水库菌群含有芳香族和有机氯等化合物降解相关基因，其可在污染物的降解和生物修复中发挥作用。2.天山北麓中段水库优势病毒均为噬菌体，不同水库的病毒群落组成存在差异，其与周边环境和人类活动等因素相关；水库中检测出CV-A10等致病性病毒，存在潜在公共卫生风险。3.天山北麓栖息地野鸟肠道细菌的多样性较为丰富，菌群组成有一定的共性，同时也存在明显的差异性，其主要与野鸟所处环境和食源结构有关。4.天山北麓栖息地野鸟粪便样品中存在多种植物和动物致病性病毒，优势病毒为噬菌体，这与宿主生存环境及植食性有关。5.天山北麓荒漠和山地野生鼠类组织中检测到逆转录病毒科、内罗毕病毒科、黄病毒科和小RNA病毒科等多种病毒，并发现多种感染人畜的病毒。6.从天山北麓湿地野鸟粪便中分离到H1N1和H9N2亚型低致病性禽流感病毒（AIV）16株，其主要由迁徙候鸟携带的AIV经多次重配产生。7.从活禽市场家禽和环境中分离到H5N6、H5N8、H9N2、H6N6、H5N2等多种亚型的AIV 90株，遗传进化分析表明分离病毒与中亚、南亚、东非和欧洲以及我国华东、华中等地区分离AIV遗传距离较近，并产生多种重配病毒，其中H5N6、H5N8、H5N2亚型AIV均为高致病性，提示天山北麓湿地在我国华中华东以及非洲和欧亚等地区间传播AIV过程中发挥了重要作用。该研究在绿洲生态和湿地生态质量监测和评价方面有重要的科学意义，在生态文明建设、重要病原监测和预警等方面有重要的应用前景。