烟草花叶病毒蚕豆分离物移动蛋白基因克隆及序列分析

Molecular cloning and sequence analysis of the movement protein gene of tobacco mosaic virus isolated in broad bean.

根据已报道的ＴＭＶ Ｕ１株系（ＴＭＶ－Ｕ１）的序列设计了特异性引物，利用ＲＴ－ＰＣＲ技术，从烟 草花叶病毒蚕豆分离物（ＴＭＶ－Ｂ）上扩增移动蛋白（ＭＰ）基因及其邻近序列。将此ｃＤＮＡ片段克隆于 ｐＢｌｕｓｃｒｉｐｔ ＳＫ质粒上，进行测序分析。结果表明：ＭＰ基因由８０７个核苷酸组成，编码２６８个氨基酸。与 ＴＭＶ－Ｕ１的ＭＰ基因序列比较，核苷酸序列及推导出的氨基酸序列的同源性分别为９９．０１％和 ９８．８９％。与ＴＭＶ－Ｙｕ的ＭＰ基因序列比较，同源性分别为９８．１４％和９８．８９％。说明ＴＭＶ的ＭＰ基因 在不同株系中是非常保守的。

The movement protein (MP) gene and its nearby sequence of tobacco mosaic virus isolated in broad bean (TMV-B) was amplified by RT-PCR technique with specific primers designed on the basis of reported TMV U1 strain (TMV-U1) sequence. The cDNA fragment was cloned into pBluscript SK plas- mid and sequenced , its sequence showed that it has 1087bp , including a MP gene ORF and its nearby se- quences. The nucleotide sequence of TMVB M P gene has 807 nucleotide in length, which encodes 268 amino acids. The nucleotide sequence and deduced amino acid sequence of TMV-B MP gene showed 99. 01 % and 98.89% homology when compared with that of TMV-U1 , while 98. 14 % and 98. 89% ho- mology were found when compared with that of TMV-Yu. These. results show the sequences of TMV MP are quite conserved.