NA蛋白对流感病毒受体结合特性影响的研究  

The role of Neuraminidase on the receptor-binding specificity of influenza A virus

作　　者：马树杰[1] 孔晖晖 施建忠[1] 谷春阳[1] 宋洋铭[1] 曲志远[1] 关云涛[1] 陈化兰[1] 

机构地区：[1]中国农业科学院哈尔滨兽医研究所兽医生物技术国家重点实验室/农业部动物流感重点开放实验室,黑龙江哈尔滨150001

出　　处：《中国预防兽医学报》2016年第7期518-522,共5页Chinese Journal of Preventive Veterinary Medicine

基　　金：自然科学基金创新群体项目(31521005)

摘　　要：为研究两株H7亚型流感病毒A/chicken/Jilin/SD020/2014(H7N2)(简称JL/020)和A/Anhui/1/2013(H7N9)(简称AH/1)受体结合特异性差异的影响机制,本实验利用反向遗传操作技术,构建一系列重配病毒和HA基因点突变病毒,检测其对受体结合特性的影响。固相ELISA检测结果表明血凝素蛋白(HA)中的57和312位氨基酸不影响流感病毒的受体结合特性,而神经氨酸酶蛋白(NA)使r-JL/020(AH/1骨架)结合SAα2,3Gal受体的结合能力高于r-AH/1(R57K/R312K),表明NA影响了流感病毒受体结合特性;同源建模进一步发现HA中的57和312位点与流感病毒受体结合结构域相距较远;交叉血凝抑制试验(HI)结果表明,H7单因子血清和H7N9全病毒血清对拯救的JL/020和AH/1病毒株的抑制价没有差异,而N2单因子血清对病毒的抑制能力存在差异。以上结果表明,NA蛋白影响了流感病毒的受体结合特性。本研究表明,除HA以外,NA也能够影响流感病毒的受体结合特性,该实验为进一步研究流感病毒受体结合特性提供了实验依据。Two H7 subtype influenza viruses, A/chicken/Jilin/SD020/2014 （H7N2） （JL/020） and A/Anhui/1/2013 （H7N9） （AWl）, were selected to study the mechanism of receptor-binding specificity in this study. To investigate which factor influences the receptor-binding property, a series of reassortants and mutant viruses were constructed by using 8 plasmid-based reverse genetics. Solid-phase ELISA assay showed that the receptor-binding specificity of AH/1 was not affected by the R57K and RInK mutations in HA, while N2 NA increased the binding affinity against SAet2,3Gal of r-JL/020（AH/1 backbone）, indicating that NA influenced the receptor-binding property. Homologous modeling further showed that the aa57 and aa312 in HA were not located in the receptor-binding domains. The hemagglutination inhibition （HI） antibody titers of the H7 HA single factor and H7N9 whole virus sera against JL/020 and AH/1 virus were both 4 and 7, respectively, while the HI titers of the N2 NA sera against the two viruses were different. All these results indicated that NA protein influenced the receptor-binding properties. This study demonstrates that, in addition to HA, NA has also an important role on receptor-binding specificity of influenza A virus, which provides a basis for further study of receptor-binding properties.

关 键 词：流感病毒 受体结合特性 血凝抑制 NA蛋白 

分 类 号：S852.65[农业科学—基础兽医学]