摘要
应用反转录 聚合酶链式反应 (RT PCR)和单链构象多态性 (single strandconformationpolymorphism ,SSCP)技术快速检测我国水稻条纹病毒 (RSV)RNA4基因间隔区 (intergenicregion ,IR)的分子变异 ,结果表明 ,我国RSVRNA4IR存在分子变异。供试的 7个分离物共有 4种泳动带型 ,其中YL、BS、JD、LY分离物完全一致 ,而SQ、PJ、JN各不相同。序列测定证实了PCR SSCP结果。各分离物RNA4IR序列均由 6 5 4个核苷酸组成 ,其中YL、BS、YL及JD 4个分离物序列完全一致 ;JN、PJ、SQ 3个分离物各不一样 ,序列之间的同源性均在 92 %～ 94%之间。IR序列内部具有两个重要的结构特征 :(1)有两处反向重复序列 ,可形成两个明显的发夹结构 ,其中一个序列比较保守 ,形成的发夹结构稳定 ;但另一个发夹结构由于碱基变异导致其稳定性在各个分离物中差异较大 ;(2 )具有插入序列 ,相对于日本M分离物 ,我国 7个分离物都有一段长 19bp的插入序列 ,这段插入序列比较保守 ,各分离物之间仅有 1～ 2个碱基的差异。
Molecular variation of intergenic regions(IRs) among seven isolates of the rice stripe virus(RSV)in China was detected by reverse transcriptase polymerase chain reaction(RT PCR) and single strand conformation polymorphism(SSCP)analysis Results showed that there were four migration patterns among these isolates The pattern of YL、BS、JD and LY isolates was identical,and those of PJ、SQ、and JN isolates could be differentiated from one another These results were confirmed by sequencing All the IRs of seven isolates were 654bp in length Sequence comparison results revealed that the sequences among YL、BS、JD and LY were 100% homologous,and those of JN、SQ and PJ isolates were different, identities among these four kinds of sequences were ranged from 92% to 94% There were two important structureal characteristics in IRs sequences Firstly,IRs sequence was rich in U and A residues where two distant hairpin structures could be formed with computer assisted folding analysis One was highly conserved and stable,but the other was rather unstable because of bases variation Secondly,there was a 19 base insertion in all IRs sequences of seven isolates in comparison to M isolate This inserted sequence was rather highly conserved,with only one or two base variation among seven isolates In this paper,the relationship between the lowest free energy of the unstable hairpin structures and the different pathogenesis among these isolates was also discussed This was the first report on molecular variability of RSV in the world
出处
《病毒学报》
CAS
CSCD
北大核心
2001年第2期144-149,共6页
Chinese Journal of Virology
基金
国家自然科学基金资助项目 ( 3 9670 489)
福建省自然科学基金资助项目 (C970 3 1)
