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分别利用５’ＲＡＣＥ和３’ＲＡＣＥ确定了ＣＭＶＳＤＲＮＡ２的５’和３’末端序列，在此基础上，利用ＲＴＰＣＲ得到了ＲＮＡ２的５’端一半的ｃＤＮＡ克隆ｐＣ２５和３’端一半的ｃＤＮＡ克隆ｐＣ２３，并通过拼接构建了ＲＮＡ２全长ｃＤＮＡ克隆ｐＣ２Ｆ。通过对ｐＣ２５和ｐＣ２３进行序列测定，得到了ＲＮＡ２的全序列。序列分析结果表明ＣＭＶＳＤＲＮＡ２由３０４８ｎｔ组成，其中存在２个部分重叠的阅读框ＯＲＦ１（７９～２６５２ｎｔ）和ＯＲＦ２（２４１４～２７４６ｎｔ），分别编码８５８ａａ的２ａ蛋白和１１１ａａ的２ｂ蛋白，并在２ａ蛋白的序列中发现了动植物病毒复制酶所特有的两个保守序列。该株系ＲＮＡ２核苷酸序列与分属ＣＭＶＩ亚组的Ｆｎｙ株系和ＩＩ亚组的Ｑ株系ＲＮＡ２的核苷酸序列同源性分别为９１７％和７５６％；２ａ蛋白的氨基酸序列同源性分别为９３８％和６７７％，２ｂ蛋白的氨基酸序列同源性分别为８３０％和５１３％。同源性比较的结果表明ＳＤ株系属于ＣＭＶＩ亚组。
The 5 ’and 3’ end sequences of CMVSDRNA2 were determined by 5’RACE and 3’RACE respectively. Based on this, RT-PCR was used to obtain the cDNA clone pC25 half of the 5 ’end of RNA2 and half The cDNA clone pC23 was cloned and the RNA2 full-length cDNA clone pC2F was constructed by splicing. By sequencing pC25 and pC23, the full sequence of RNA2 was obtained. The result of sequence analysis showed that CMVSDRNA2 consists of 3048nt, including two partially overlapping reading frames ORF1 (79 ~ 2652nt) and ORF2 (2414 ~ 2746nt), encoding 2a protein of 858aa and 2b of 111aa respectively, Two conserved sequences unique to the plant and animal virus replicase were found in the sequences. The nucleotide sequence of the nucleotide sequence of RNA2 in this strain was 917% and 756% homologous with that of Q strain RNA2 in Fny strain and II subgenome respectively belonging to CMVI subgroup; The amino acid sequence homologies were 938% and 677%, respectively. The homology of 2b protein was 830% and 513% respectively. The results of homology comparison indicated that the SD strain belongs to the CMVI subgroup.