抗ORFV免疫球蛋白重链可变区基因序列的RT-PCR扩增及其多样性  

Molecular cloning and characterization of Ig heavy chain variable region (IgH) from the spleen of sheep infected with Orf virus

作　　者：包英夫[1] 宋德光[1] 贺文琦[1] 张希牧[2] 李吉达[1] 王改丽[1] 毕经影[1] 赵魁[1] 高丰[1] 

机构地区：[1]吉林大学动物医学学院,吉林长春130062 [2]北京大学实验动物中心,北京100871

出　　处：《中国兽医学报》2014年第4期526-529,共4页Chinese Journal of Veterinary Science

基　　金：国家自然科学基金青年基金资助项目(31101785);教育部高等学校博士点专项科研基金资助项目(20120061130001);吉林省世行贷款农产品质量安全资助项目(2011-Y20)

摘　　要：利用RT-PCR方法从羊传染性脓疱病毒（Orf virus,ORFV）感染绵羊脾脏总RNA中扩增获得免疫球蛋白（immunoglobulin,Ig）重链可变区cDNA克隆,随机挑选52个阳性克隆进行测序,获得49条完整的不重复序列。序列比对结果显示,49条序列的核苷酸同源性分别为84.3%（H7与H38）-100%（H5与H6）不等;绵羊IgH可变区V片段氨基酸聚类结果显示,克隆H1-H49的VH区段自动聚类为2个相对独立的单位。通过BLAST-N程序在GenBank数据库在线搜索,并结合其他参考序列进行比较分析,分析数据显示,D片段从9到46个碱基长度不等,无论是在核苷酸还是氨基酸序列上,其同源性均存在高度的变异性;结合其亲水性分布图可知,可变区的亲水性氨基酸主要分布在VH区域和D高变区,对照抗原指数图和表面可能性图,亲水性强的VH区域和D高变区易形成抗原决定簇。The cDNA of the immunoglobulin heavy chain variable regions were amplified by RT- PCR from the spleen of sheep infected with Orf virus. The 52 positive clones were randomly se- lected and completely sequenced over the variable regions. The 49 complete sequences were ob- tained without duplicating. The nucleoticle identity of 49 sequences ranged from the lowest 84.3% （that of H7 and H38） to the highest 100% （that of H5 and H6）, The clustering analysis of amino acids deduced by V regions of IgH showed that all clones （H1 to H49） were classied into two branches. After comparing with other IgH sequences in BLAST,the length of D regions were dif- ferent from 9 to 46 bases. The homology of nueleotide sequences and deduced amino acid sequences showed obvious variability. The hydrophilic amino acids mainly distributed in VH regions and D hypervariable regions combinated with the hydrophilicity profile. The VH regions and D hypervari- able regions having stronger hydrophilicity usually formed antigenic determinants.

关 键 词：羊传染性脓疱病毒 免疫球蛋白 重链 可变区 

分 类 号：S852.65[农业科学—基础兽医学]