广东地区H9N2亚型禽流感病毒HA和NA基因生物学特征分析  

Biological Characteristic of HA and NA Genes of H9N2 Avian Influenza Virus in Guangdong Province

作　　者：曾庆航 刘杨 孙敏华 胡鑫宇 谢梓民 张敏霞 袁朝霞 廖明 ZENG Qinghang;LIU Yang;SUN Minhua;HU Xinyu;XIE Zimin;ZHANG Minxia;YUAN Zhaoxia;LIAO Ming(College of Animal Science&Technology,Zhongkai University of Agriculture and Engineering,Guangzhou 510225,China;Institute of Animal Health,Guangdong Academy of Agricultural Sciences/Key Laboratory of Livestock Disease Prevention of Guangdong Province/Key Laboratory for Prevention and Control of Avian Influenza and Other Major Poultry Diseases,Ministry of Agriculture and Rural Affairs,Guangzhou 510640,China)

机构地区：[1]仲恺农业工程学院动物科技学院,广东广州510225 [2]广东省农业科学院动物卫生研究所/广东省畜禽疫病防治研究重点实验室/农业农村部禽流感等家禽重大疾病防控重点实验室,广东广州510640

出　　处：《广东农业科学》2023年第5期103-111,共9页Guangdong Agricultural Sciences

基　　金：国家重点研发计划(2022YFD1801000);“十四五”广东省农业科技创新十大主攻方向“揭榜挂帅”项目(2022SDZG02);广东省基础与应用基础研究基金(2022A1515110737);云南省廖明专家工作站项目(202105AF150077)。

摘　　要：【目的】监测广东地区H9N2亚型禽流感病毒(Avian Influenza Virus,AIV)的遗传变异和分子进化趋势,为我国H9N2亚型AIV的防控提供参考。【方法】对2022年广东地区3株H9N2亚型AIV的HA和NA基因进行扩增、克隆、测序,使用DNAStar、PhyloSuite软件进行序列拼接和比对,再运用MEGA、Megalign、NetNGlyc 1.0Server等软件,对其核苷酸和氨基酸序列进行遗传进化、核苷酸同源性分析,以及受体结合、蛋白活性、耐药性和糖基化等关键位点分析。【结果】系统发育树和核苷酸同源性分析结果显示,3株分离株的HA和NA基因分别属于h9.4.2.5分支和1分支,与早期毒株的核苷酸同源性分别为81.6%~91.7%和88.2%~91.2%,分别命名为h9.4.2.5c分支和1.2分支;核苷酸和氨基酸序列分析发现,HA裂解位点为PSRSSR↓GLF,受体结合位点产生I155T、H183N、A190T/V、T212I、Q226L、Q227M突变,糖基化位点产生218N非糖基化和新增313N糖基化突变;NA茎部缺失187~195位9个核苷酸(ACAGAGATA),导致缺失63~65位3个氨基酸(TEI);NA红细胞结合位点产生K/E/S368N、D369N突变,与NA蛋白活性,耐药性的相关位点E119、D151、R152、R224、E276、R292、R371均未发生突变。【结论】2022年广东地区分离的3株H9N2亚型AIV已经进化成新的亚群,部分突变可能增强了对哺乳动物的适应性,且其抗原性发生改变,但尚未获得对奥司他韦和扎那米韦等抗流感病毒药物的耐药性。【Objection】This study aimed to monitor the genetic variation and molecular evolutionary trends of H9N2 avian influenza virus(AIV)in Guangdong,and provide reference data for the evolutionary analysis and prevention and control of H9N2 AIV in China.【Method】The HA and NA genes of three H9N2 AIV strains isolated from Guangdong in 2022 were amplified,cloned,and sequenced.The DNAStar and PhyloSuite software were used for sequence assembly and alignment.The MEGA,Megalign,NetNGlyc 1.0 Server,and other software were used for genetic evolution,percent identity,receptor binding,protein activity,drug resistance,and glycosylation site analysis of their nucleotide and amino acid sequences.【Result】The phylogenetic tree showed that the HA gene of the three isolates belonged to the clade h9.4.2.5 and the NA gene belonged to the clade 1.However,the nucleotide homology with the early strain was only 81.6%~91.7%and 88.2%~91.2%,formed new clade named clade h9.4.2.5c and clade 1.2,respectively.The nucleotide and amino acid sequence analysis revealed that the HA cleavage site was PSRSSR↓GLF.The receptor binding site underwent I155T,H183N,A190T/V,T212I,Q226L,and Q227M mutations.The glycosylation site underwent 218N non-glycosylation and acquired new glycosylation site at 313N.The NA stalk showed nine nucleotides deletion at positions 187-195(ACAGAGATA),leading to the loss of three amino acids at positions 63-65(TEI).The absorbtion site of NA on red blood cells showed K/E/S368N and D369N mutations.No related mutations to neuraminidase activity and drug resistance were found at the E119,D151,R152,R224,E276,R292,and R371.【Conclusion】The HA and NA genes of the three H9N2 AIV isolated from Guangdong in 2022 had evolved into a new subgroup.Some mutaitons suggest that prevalent H9N2 in Guangdong may enhanc adaptability of mammals and its antigenicity has changed.Moreover,it has not yet acquired resistance to durgs oseltamivir and zanamivir.

关 键 词：H9N2 禽流感 HA基因 NA基因 遗传进化 生物学特征 

分 类 号：S858.325.3[农业科学—临床兽医学]