侵染白菜的黄瓜花叶病毒分离物基因组的全序列分析

Complete Sequence Analysis of Cucumber mosaic virus CTL Isolate

对浙江省杭州地区白菜(Brassica campestris L.ssp.chinensis var.commuis Tsenet Lee.)上获得的CMV分离物(CMV-CTL)进行了全长克隆和基因组序列分析。结果显示:CMV-CTL的RNA1(Gen-Bank序列号:EF213023)全长为3357个核苷酸(nt),编码993个氨基酸(aa)的1a蛋白;RNA2(Gen-Bank序列号:EF213024)全长为3047nt,编码858aa的2a蛋白和111aa的2b蛋白;RNA3(GenBank序列号:EF213025)全长为2217nt,编码278aa的MP蛋白和218aa的CP蛋白。序列相似性分析表明,CMV-CTL与CMV亚组B中株系IA相似性最高,RNA1、RNA2和RNA3与该株系的相似性分别为91·3%、91·3%和93·6%。CP基因和RNA3的5′NTR核酸序列系统发生树分析表明,CMV-CTL与中国大多数CMV分离物一样,属于CMV亚组IB。

Isolate CMV-CTL was obtained from Brassica campestris L. ssp. chinensis var. commuis Tsen et lee. , in Hangzhou, Zhejiang Province. The full-length cDNA sequence of genomic RNAs of the isolate was determined by RT-PCR and sequencing. The results showed that CMV-CTL RNA1 （GenBank accession No. EF213023 ） consists of 3 357 nucleotides （nt）, encoding 1a protein of 993 amino acids residues （aa）. RNA2 （GenBank accession No. EF213024） consists of 3 047 nt, encoding 2a protein of 858 aa and 2b protein of 111 aa. RNA3 （GenBank accession No. EF213025） contains of 2 217 nt, encoding 3a protein of 278 aa and CP of 218 aa. CMV-CTL showed the highest sequence identities with strain IA which belongs to CMV sub- group IB. The sequence identities of RNA1, RNA2 and RNA3 between CTL and IA strains were 91.3%, 91.3% and 93.6%, respectively. Phylogenetic analysis of CP and 5′NTR of RNA3 suggested that CMV-CTL belongs to CMV subgroup IB.