黄瓜花叶病毒M株系RNA3的变异分析及全长克隆的构建  

Diversity Analysis of RNA3 of Cucumber Mosaic Virus Strain M and Construction of Its Full-length cDNA Clone

作　　者：王海河[1] 蒋继宏[1] 吴祖建[1] 林奇英[1] 谢联辉[1] 

机构地区：[1]福建农业大学植物病毒研究所,福州350002

出　　处：《农业生物技术学报》2000年第2期180-185,共6页Journal of Agricultural Biotechnology

摘　　要：为了探讨由多年地理环境变化引起的黄瓜花叶病毒M株系RNA3的核苷酸序列变异状况，对其RNA3的序列作了再次测定（记为MX）。结果表明，MX－RNA3全长为2215个核苷酸，具有两个阅读框，即3a和外壳蛋白编码区。与M株系相比总共有8个核苷酸发生变异；3a和外壳蛋白中各有一个氨基酸发生改变。在核苷酸和推测的氨基酸水平上与Y株系（测定过两次，分别记为Y1和Y2）和Fny株系的比较发现，RNA3的变异率很低，但非编码区有相对较育的变异率，而编码区无论在核苷酸或氨基酸水平上均比较保守，尤其是3a编码区。这表明黄瓜花叶病毒的保守核苷酸和氨基酸对维持其自身的功能稳定性有重要作用。最后构建了含T7启动子的RNA3全长CDNA克隆。The nucleotide sequence of RNA3 of cucumber mosaic virus (CMV strain M, signed MX here) was determined and compared at both the nucleic acid and protein level with the previously sequenced RNA3. The results showed that CMV-MX RNA3 is composed of 2215 nucleotides and contains two open reading frames (ORFs), the 3a gene and coat protein gene, with total eight point mutations in nucleotide level, and one amino acid change in 3a and coat protein respectively. Compared with the other strains (strain Y1 or Y2) and Fny, the RNA3 seemed to be very little divergent at either nucleotide or amino acid level. The nontranslational regions (NTRs) have higher diversity. The amino acid sequence similarity is also high, esPecially in the ORFs of 3a. After a long time evolution and geographical changes, the RNA3 of strain M contains little variation at both levels of nucleotide and amino acid sequence,which suggests that the maintenance of the very conserved nucleotide or amino acid sequences have important functions in the stability of CMV. The full-length cDNA clone of RNA3 including T7 promoter was constructed.

关 键 词：黄瓜花叶病毒 M株系 RNA3序列 变异分析 

分 类 号：S432.41[农业科学—植物病理学] S642.2[农业科学—农业昆虫与害虫防治]