云南省烟草花叶病毒和黄瓜花叶病毒外壳蛋白基因克隆及序列分析

cDNA cloning and sequence analysis of coat protein genes of TMV and CMV isolated from tobacco in Yunnan province

以从云南省主要烟区烟草上分离到的烟草花叶病毒 (Tobacco mosaic virus,TMV)和黄瓜花叶病毒 (Cucumber mosaic virus,CMV)的 RNA为模板 ,采用 RT- PCR技术 ,对 TMV云南分离物 (TMV-YN)的外壳蛋白 (Coatprotein,CP)基因及 3’端非编码区和 CMV云南分离物 (CMV- YNa)的 CP基因进行了 c DNA克隆和序列测定 .结果表明 ,TMV- YN的 c DNA全长 6 84个碱基 (EMBL登录号为AJ2 390 99) ,通过 Gen Bank进行同源性比较发现 :其 5'端的 4 80个碱基为 CP基因 ,编码 159个氨基酸 ;3'端的 2 0 4个氨基酸为非编码区 ;此 CP基因与 TMV- U1株系和 TMV韩国普通株系核苷酸同源性均为 10 0 % . CMV- YNa的 CP基因全长 6 57个碱基 (EMBL登录号为 AJ2 390 98) ,编码 2 18个氨基酸 ;此CP基因与 CMV亚组 I的 CMV- RB株系、CMV- 117F株系和 CMV- Y株系的核苷酸同源性分别为96 %、93%和 92 % .

The cDNA of coat protein gene and its 3' non coding region of tobacco mosaic virus and coat protein gene of cucumber mosaic virus isolated from the tobacco in Yunnan province was synthesized by RT PCR. The amplified cDNA fragments were then cloned and sequenced. The fragment of TMV YN comprises 684bp (EMBL accession number: AJ239099), including 480bp of CP gene encoding 158 amino acids and a 204bp of 3' non coding region. Comparison either the nucleotide sequence of CP gene or that of 3' non coding region demonstrated that the TMV YN is identical to the TMV U1 strain and TMV common strain in Korea, with 100% homology. The CP gene of CMV YNa consists of 657nt encoding 218 amino acid (EMBL accession number: AJ239098). The nucleotide sequence of CMV YNa has 96%, 93% and 92% nucleotide identities with CMV RB, CMV 117F and CMV Y, respectively.