猪瘟病毒石门株与兔化弱毒株gp55基因的克隆与序列分析

猪瘟病毒石门系强毒株及兔化弱毒疫苗株（ＨＣＬＶ株）是我国的标准毒株,囊膜糖蛋白ｇｐ５５（又称Ｅ１）是该病毒最重要的保护性抗原。本实验采用反转录ＰＣＲ扩增了这两个毒株的ｇｐ５５基因。序列分析结果表明：１．石门株和兔化弱毒株糖蛋白Ｅ１的氨基酸序列含有１５个半胱氨酸残基（Ｃｙｓ）,其数量及位置与国外４株猪瘟病毒（Ａｌｆｏｒｔ、Ｂｒｅｓｃｉａ、ＡＬＤ和ＧＰＥ＾－）完全一样。Ｅ１中Ｃｙｓ的数量及位置的保守性

CLONING AND SEQUENCE ANALYSIS OF E1 GENE OF TWO CHINESE HOG CHOLERA VIRUS STRAINS

In this report, we showed the amplification of the major antigenic protein E1 (gp55) gene of two Chinese hog cholera virus strains,Shimen and "C".We accomplished this by designing two set of degenerate primers that were capable of amplifying 5' -terminal half and 3' -terminal half of E1 gene respectively.In addition, the cDNA cloning and nucleotide sequencing of the amplified E1 genes were performed.The amino acid sequence data derived showed that:A.the number and location of cysteine residues in E1 amimo acid sequence of strain"C" and strain Shimen were identical to those of reference strains Alfort,Brescia,ALD and GPE -,revealing that antigenic E1 of HCV had a conserved structure frame; B.the signal sequence at N-terminal and the transmembrane sequence at C terminal were highly conserved,however the antigenic regions located at N-terminal half of E1 were variable,especially at the region of amino acid residues 702-742; C.Comparison of amino acid sequences of E1 between the strain"C" used in our study and the strain"C" used in Rijn's study in the Netherlands showed some amino acid substitutions which scattered along the whole E1 sequence,indicating the strain "C" might vary genetically to some extents in the course of many years application.