2株欧亚与北美谱系重排H6N8亚型禽流感病毒的遗传进化及分子特征分析  

Genetic evolution and molecular characterization analysis of two Eurasian and North American lineage rearrangement H6N8avian influenza viruses

作　　者：胡鑫宇 李元果 孔云逸 王铁成 秦思源[2] 周景莹 孟德荣[4] 徐钰[2] 夏咸柱[1] 高玉伟 HU Xin-yu;LI Yuan-guo;KONG Yun-yi;WANG Tie-cheng;QIN Si-yuan;ZHOU Jing-ying;MENG De-rong;XU Yu;XIA Xian-zhu;GAO Yu-wei(Changchun Veterinary Research Institute,Chinese Academy of Agricultural Sciences,Changchun130122,China;State Forestry Administration Wild Animal Epidemic Surveillances;Tumuji National Nature Reserve;Cangzhou Normal University)

机构地区：[1]中国农业科学院长春兽医研究所,吉林长春130122 [2]国家林业局野生动物疫源疫病监测总站 [3]内蒙古图牧吉国家自然保护区 [4]沧州师范学院

出　　处：《中国病原生物学杂志》2022年第2期130-135,共6页Journal of Pathogen Biology

基　　金：国家自然科学基金项目(No.31970502)。

摘　　要：目的解析监测中发现的欧亚与北美谱系重组H6N8亚型禽流感病毒的遗传进化及分子特征,为禽流感病毒跨洲际传播及基因重排研究提供支持。方法2019年秋季在图牧吉地区采集雁鸭类粪便样品,分离H6N8亚型禽流感病毒并进行全基因序列测定,分析其遗传进化及分子特征。结果共采集雁鸭类粪便及拭子样品5062份,分离到2株H6N8LPAIV(TMJ43、TMJ120)。遗传进化分析显示,分离株病毒NA与北美的阿拉斯加地区所分离的H3N8亚型AIV的NA节片聚集在同一进化分支,HA和其它6个内部基因节片均属于欧亚进化分支,且两株禽流感病毒分别有不同的重配发生。2株H6N8亚型禽流感病毒为欧亚谱系与北美谱系基因重排毒株,其中N8基因最近一次欧亚与北美基因节片重排发生在2016年。分子特征分析显示,HA蛋白的碱性裂解位点为PQIETR↓GLF,符合低致病性禽流感病毒的特征。在NP蛋白,发生了具有增强鸡禽流感毒力的A184K突变。在TMJ43,NS1蛋白发生了能增强哺乳动物毒力的A/P42S突变。结论在我国内蒙古地区分离的2株H6N8亚型禽流感病毒为欧亚谱系和北美谱系的重排毒株,两毒株均发生了增强家禽和哺乳动物感染能力的突变。表明北美毒株通过候鸟迁徙进入我国,与欧亚谱系毒株发生重配并在野鸟中频繁出现,可为禽流感病毒的跨洲际传播研究提供信息支持。Objective Analyze the genetic evolution and molecular characteristics of the Eurasian and North American lineage recombinant H6N8subavian influenza viruses found in surveillance,and provide support for the research on the intercontinental spread and gene rearrangement of avian influenza viruses.Methods In the autumn of 2019,the fecal samples of anatians were collected in the Tumuji area,and epidemiological investigations and studies were carried out through virus isolation,complete gene sequence determination and genetic evolution analysis.Results Two H6N8LPAIV strains(TMJ43,TMJ120)were collected in Tumuji area of Inner Mongolia.Genetic evolution analysis showed NA segments of the h6n8and H3N8subtype AIV,isolated from Alaska in North America were clustered in the same evolutionary branch.HA and the other 6gene segments belonged to the Eurasian evolutionary branch,and two h6n8shad different reassortment.Analysis showed that the two isolated H6N8subtype avian influenza viruses were genetically rearranged strains of Eurasian and North American lineages.Further analysis proved that the last rearrangement of Eurasian and North American gene segment about the N8gene occurred in 2016.Molecular analysis showed that all HA protein cleavage sites were PQIETR↓GLF,which was consistent with the characteristics of low pathogenic avian influenza virus.In the NP protein,there was an A184Kmutation that could enhances the virulence of avian influenza in chickens.In the TMJ43NS1protein,the A/P42Smutation that could enhance the virulence of mammals occured.Conclusion The two H6N8subtype avian influenza viruses isolated in Inner Mongolia are rearranged strains of the Eurasian and North American lineages,with mu tations enhancing the ability to infect poultry and mammals.All results show that North American strains have entered my country through migratory birds,reassorted with Eurasian lineage strains and frequently appeared in wild birds.This study provides information support for the intercontinental spread of avian influenza vir

关 键 词：H6N8 重配 低致病性禽流感病毒 跨洲际传播 

分 类 号：R373.1[医药卫生—病原生物学]