猪瘟野毒E2基因同源性比较

以人工感染发病猪的脾为材料提取总RNA ,根据已报道的猪瘟病毒基因组序列 ,设计合成了 2对引物 ,以总RNA为模板 ,利用反转录聚合酶链式反应 (RT PCR)、套组聚合酶链式反应(nPCR)及测序技术 ,对流行于我国甘肃省、陕西省、宁夏和广西自治区的 5株野毒株的主要外膜糖蛋白E2基因的核苷酸序列进行了测定 ,用DNAstar软件比较分析了 5株野毒之间及其与猪瘟兔化弱毒株 (C ST株 )E2基因的核苷酸序列和推导的氨基酸序列的同源性。结果发现 ,5株野毒与C ST株核苷酸序列的同源性为 81.7%～ 83.1% ,氨基酸同源性为 87.3%～ 88.6 % ,表明它们之间存在较大的差异 ;但 5株野毒之间核苷酸序列的同源性高达 98.8%～ 99.3% ,氨基酸同源性为96 .6 %～ 99.2 % ,表明它们之间的差异较小

Homologic comparison of the E2 gene nucleotide sequences of CSFV field strains with the C-strain

The major protective antigen endoding regions of E2 genesof field isolates of CSFV from five regions in Chinawere amplified by RT PCR and Nest PCR. Then they were cloned and sequenced. Comparison and analysis of the nucleotide sequences and the deduced amino sequences among the five strains from different source with CSFV C strain were performed by computer with the computer software. The further study of the five strains genetic relationshipwas done by the phylogenetic tree constructed on the base of analyzing the data of the E2gene with computer software. The results showed some substitutions of nucleotide or deduced aminoacid scatteringalong the E2genesortheirencoding proteinswith the homology of the nucleotide and amino acid sequences being 81.7%-83.1% and 87.3%-88.6%, respectively, which indicated the five field strains had varied genetically to a certain extent. But the identical rates of the five field serains reached 98.8%-99.3% and 96.6%-99.2%, respectively, which indicated the homology among the five field strains were higher.