贵州省H9N2亚型禽流感病毒HA基因的遗传演化分析  

Analysis of genetic evolution of the HA gene of avian influenza virus subtype H9N2 in Guizhou province

作　　者：杨均[1] 王开功[2] 汪德生[2] 朱永毅[1] 杨敬[1] 潘明兴[1] 颜德林[1] 刘长宁[1] 

机构地区：[1]黔南民族职业技术学院生物工程系,贵州都匀558022 [2]贵州大学动物科学学院,贵阳550025

出　　处：《黑龙江畜牧兽医》2016年第5期5-8,12,共5页Heilongjiang Animal Science And veterinary Medicine

基　　金：贵州省农业厅兽医科技计划项目(2014-06)

摘　　要：为了研究H9N2亚型禽流感病毒（AIV）贵州株HA基因的遗传特点,试验采用RT-PCR方法扩增H9N2亚型AIV贵州株HA基因片段,并进行序列测定和遗传进化分析,并对HA蛋白质的裂解位点、受体结合位点和潜在的糖基化位点进行分析。结果表明：分离株HA基因全长为1 738 bp,可编码561个氨基酸;与国内外参考株相应序列的同源性为82.4%~98.2%;推导氨基酸序列的裂解位点为paRSSR↓GLF,属于低致病性H9N2亚型AIV;含有5个潜在的糖基化位点,在145,218,551位缺失3个潜在的糖基化位点;受体结合位点分别在202位和204位发生亮氨酸（L）→异亮氨酸（I）和谷氨酰氨（Q）→苏氨酸（T）替换;HA基因系统发育树上显示该毒株为欧亚种系Y280分支。说明H9N2亚型AIV贵州株HA基因存在一定的变异,应加强对该类病毒的分子流行病学监测。To study the genetic characteristics of hemagglutinin （HA） genes from Guizhou strain of avian influenza virus （AIV） subtype H9N2, the HA gene fragments of Guizhou strain of AIV subtype H9N2 were amplified by RT - PCR. Sequencing and the analysis of genetic evolution were performed, and the cleavage site, receptor binding sites, and the potential glycosylation sites of HA protein were analyzed. The result showed that the full length of the HA gene of the isolate was 1738 bp, encoding for a protein of 561 amino acids. The HA gene sequences of the isolate shared 82.4% to 98.2% homologies with those of reference strains at home and abroad. The cleavage site of deduced amino acid sequence was paRSSR ,L GLF, which belonged to low pathogenic AIV subtype H9N2. There were five potential glyeosylation sites, and three deletions of potential glycosylation sites were found at 145,218, and 551 sites. The replacement of leucine （L） to isoleucine （I） and glutamine （Q） to threonine （T） was found at 202 and 204 sites in the receptor binding sites. Phylogenetic analysis of the HA gene revealed that Guizhou strain of AIV subtype HgN2 belong to Y280 branch of Eurasian germ line. The results indicate that the HA genes of Guizhou strain of AIV subtype H9N2 exists certain variation, thus, the molecular epidemiological surveillance for AIV subtype H9N2 should be strengthened.

关 键 词：禽流感病毒 H9N2亚型 HA基因 序列分析 遗传特点 

分 类 号：S852.659.5[农业科学—基础兽医学] Q784[农业科学—兽医学]