利用RT PCR方法 ,扩增获得西瓜花叶病毒 2号 (WMV 2 )山西分离物CP基因 ,并克隆到pUC T载体中 .核苷酸序列测定结果表明 ,山西分离物CP基因全长为 846个核苷酸 ,编码由 2 81个氨基酸组成的 31 5kDa蛋白 .与国外已报道的WMV 2CP基因相比 ,其核苷酸序列同源性为 92 8%～ 93 9% ,由此推导的氨基酸序列同源性为 95 4%～ 96 4% .山西分离物外壳蛋白有 4个氨基酸残基明显不同于其它分离物 ,其中蚜传株系的特征结构域DAG突变为YAG . CP gene of Shanxi isolate of watermelon mosaic virus 2 (WMV 2) was amplified by RT-PCR and cloned into pUC T vector.The results of nucleotide sequencing showed that the CP gene of Shanxi isolate was 846 Nucleotide sequence and encoded a 31 5 kDa protein consisting of 2 81 amino acids.The nucleotide sequence homology was 92 8% -93 9% with the reported WMV 2CP gene in foreign countries, and the deduced amino acid sequence The homology was 95 4% ~ 96 4% .The four amino acid residues of the coat protein of Shanxi isolate were obviously different from those of other isolates, in which the DAG mutation of the aphid-derived strain was YAG.