【摘要】 应用聚合酶链式反应技术（ＰＣＲ）扩增了水稻矮缩病毒（ＲＤＶ）中国福建分离物基因组第１２号片段（Ｓ１２）的全基因序列，并对该基因进行了亚克隆和序列分析。结果表明克隆片段全长为１０６６ｂｐ，含有４个开放阅读框架（ＯＲＦ），分别编码３４ｋＤ、８ｋＤ、７ｋＤ和４ｋＤ的多肽。与日本ＲＤＶＳ１２在核苷酸水平上的同源率为９４．５％，与相应ＯＲＦ（ＯＲＦ１－４）编码多肽的同源率分别为９１．３％、９７．８％、９７．６％和８４．４％。此外，将这几个ＯＲＦ编码的多肽与同组伤瘤病毒（ＷＴＶ）、水稻瘿矮病毒（ＲＧＤＶ）相应ＯＲＦ编码的多肽进行同源性比较发现，３４ｋＤ多肽与ＷＴＶ和ＲＧＤＶ相应多肽无显著的序列同源性，但ＯＲＦ２和ＯＲＦ３编码的多肽在同组中却有明显的保守性。由此说明这几种小的多肽在病毒侵染和复制中有着十分重要的作用。更多还原

【Abstract】 ice Dwarf Virus(RDV)segment S12 full length cDNA was synthesized and amplified by polymerase chain reaction(PCR).The PCR product was cloned and sequenced.The results have shown that the cloned fragment is 1,066bp in length and contains four open readingframes(ORF).The four ORFs encode four polypepetides with molecular weight of 34kD(ORF1),8kD (ORF2),7kD (ORF3)and 4kD (ORF4),respectively.Amino acid sequence comparison of polypepetides encoded by RDV S12 ORF1,ORF2,ORF3 and ORF4 of Chinese Fujian and Japanese isolated showed significant homology (91.3%,97.8%,97.0%and 84.4%,for ORF1,2,3 and 4,respectively).In addition,amino acid sequence comparison of small polypepetides encoded by RDV S12 ORF2-3 with WTV and RGDV S9 small ORFhave shown that the small ORFs are conservative in the phytoreovirus genus.These resultssuggest that the small ORF may play a very important functions in vivo.更多还原