禽流感病毒血凝素保守氨基酸对其受体结合位点的影响  

The Influence of the conservative amino acide of hemagglutinin to the receptor binding site of avian influenza virus

作　　者：贾红玲[1] 苏艳[2] 吴润[1] 

机构地区：[1]甘肃农业大学动物医学学院,甘肃兰州730070 [2]中国科学院微生物研究所,北京100101

出　　处：《中国预防兽医学报》2008年第7期500-504,共5页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家973项目(2005CB523001)

摘　　要：采用PCR定点突变技术,对H5N1亚型禽流感病毒的血凝素HA基因受体结合位点相关的保守氨基酸分别进行以下位点的定点突变:35位K→R、45位D→N、98位Y→F、193位K→R和267位A→T,构建突变表达载体pCI-HA,转染293T细胞进行瞬时表达。流式细胞检测结果显示:193位K→R的突变体的HA的表达显著增加;98位Y→F突变体的HA的表达受到显著抑制。同时,血球吸附试验表明,同一HA突变体吸附鸡红细胞和马红细胞时,显示出不同的红细胞吸附能力。因此,受体结合位点相关的193位和98位的保守氨基酸不仅对受体结合位点结构域的形成有影响,它们还在决定AIV感染的宿主特异性中具有重要的作用。The HA gene of subtype AIV was amplified by PCR. Five mutations at the receptor site of the H5N1 subtype HA protein was created by site-directed mutagenesis, where amino acids of K （35）, D （45）, Y （98）, K （193） and A （267） changed to R （35）, N （45）, F （98）, R （193） and T （267）. The mutated gene was inserted into expression vectors and transfected into 293T cells. The expression products were analysis by flow cytometry and erythrocyte absorbing test. Comparing with the wide type of the HA, mutation at position 193 from K to R markedly increased HA expression; whereas, mutation at position 98 from Y to F resulted in decreased HA expression. The mutation appeared also affect the ability of HA to attach to the erythrocytes. In conclusion, the conservative amino acid related to receptor binding site play a very important role in forming the conformation of the receptor. The amino acid of at position 193 and 98 may influence the AIV host preference.

关 键 词：禽流感病毒 H5N1亚型 血凝素 受体结合位点 定点突变 

分 类 号：S852.659[农业科学—基础兽医学]