猪瘟病毒石门株NS4A基因的克隆、测序及分析

CLONING,SEQUENCING AND ANALYSIS OF NS4A GENE FROM HOG CHOLERA VIRUS SHLMEN STIRAIN

采用RT-PCR技术，利用一对引物，从感染猪血中成功扩增了猪瘟病毒强毒石门株NS4A基因，片段大小为757bp，与预期大小一致。克隆后经酶切鉴定，自动化测序。序列比较表明，该基因为最保守的基因之一，其中石门株序列与ALD，GPE，HCLV及Brescia株均有很高的同源性，由其推导的氨基酸的同源性高达100％。仅与Alfort株的同源性消低。对石门株序列与同属的BVDVSD－1株和NADL株序列进行了比较。

Usng a specific pair of primers, the NS4A gene of hOg chocra virus (classical swine fevervius) Shimen strain was successfully arnpllfied with RT- PCR method from the total RNA extracted from the anticoagulant blood of infccted pig. The length of the fragmnt is 757bp, identical to what antjcipated. The PCR preduct was cloned and then automated-sequenced. Sequencecomparison revealed that NS4A was one of the most conservative genes. NS4A gene of Shimenstrain has a very high homology with ALD, GPE -, HCLV, and Brescia strain. And the deduced amino acid sequences homologies are as high as 100% . Only has a little lower homologywith klfort strain. Comparian of NS4A genc of Shimen strain with other pest viruses of the samegenus such as BVDV, SD-1, and NADL has. also been done.