TMV、PVY福建分离物分子鉴定及末端区域变异分析

Molecular Identification and Variation Analysis of Terminal Region for TMV and PVY Isolates from Fujian

为及时准确地鉴定出病毒病原和追踪了解病毒病流行变异趋势,使用特异性引物对福建烟区病毒烟叶样品进行RT-PCR分析,分别鉴定出病毒病原为TMV和PVY。序列测定结果表明PCR扩增产物为预期的TMV 5’末端和PVY 3’末端序列,大小分别为959和646个核苷酸,均包含末端非编码区和部分病毒功能基因蛋白编码区。将所获得的病毒末端序列与国内外报道的主要病毒分离物的同一区域进行比较,分析结果显示TMV 5’端非编码区保守性极强,不同分离物之间部分126 kDa或183 kDa编码蛋白N端编码区表现出一定程度的变异(突变),PVY外壳蛋白编码区与3’末端非编码区变异数量差异不大,变异(突变)均主要为碱基转换,环境自然选择压力对病毒基因组变异(突变)具有一定的影响。

To accurately and timely identify viral pathogens and track variation and epidemic trend of viral diseases,specific primers were used in RT-PCR,by which TMV and PVY were identified respectively from infected tobacco leaves collected from Fujian Province.The results of viral sequence analysis showed that the amplification products were the 5＇ terminal region of TMV and the 3＇ terminal region of PVY with sequence lengths of 959 and 646 nt respectively,both including of terminal noncoding region and part of the coding region of viral functional genetic protein.Comparing the obtained terminal sequence with the same regions of the viral isolates in NCBI revealed that the noncoding region of 5＇ terminal end of TMV was highly conservative,N terminal coding region of some of 126kDa or 183kDa protein among different TMV isolates presented some variations（mutations）.In terms of numerical differences of variation,the difference between CP coding region and 3＇ terminal region of PVY was not apparent.The variations（mutations） mainly came from base conversion.Natural selection pressures affected virus genome variation（mutation） to a certain degree.