水稻条叶枯病毒基因组组分3的克隆与序列分析

利用ＲＴ－ＰＣＲ技术，合成并扩增了水稻条叶枯病毒（ＲＳｔＶ）中国云南分离 物基因组组分３的全长ｃＤＮＡ。将ＰＣＲ产物克隆在载体ｐＣＲⅡ上，进行全序列测定。将所得核苷酸序列及其所推导的氨基酸序列与日本分离物Ｔ进行同源性比较，结果表明，在核苷酸水平上，两分离物的５’端非编码区序列相同，ｖＯＲＦ、ｖｃＯＲＦ及基因间非编码区序列的同源性分别为９７．６％、９６．８％及８７．６％，而３’端非编码区同源性为９８

Cloning and Sequence Analysis of Rice Stripe Virus Genome Segment 3 of the Chinese Isolate Y

The cDNA fragment covering full length sequence of RStV RNA3 of Yunnan isolate in China was obtained by RT PCR. The PCR derived fragment was then cloned into vector pCRII. The cloned cDNA was sequenced. Comparison of the nucleotide and deduced amino acid sequences with those of the Japanese isolate T was made. The results showed that at the nucleotide level, vORF, vcORF and the intergenic region had 97.6%, 96.8%, and 87.6% identity respectively, the 5' untranslational region was exactly the same as that of the Japanese isolate T, while the 3' terminal sequence had 98.9% identity, differing by one nucleotide; at the amino acid level, vORFr and vcORF had 99.1% and 98.5% identity respectively. Therefore, as well as being exactly the same size for the two isolates, the amino acid sequences of the coding regions and the 5' and 3' terminal sequences were well conserved. Our results indicated that the Chinese isolate Y is closely related to the Japanese isolate T.