Söderlund H, Keränen S, Lehtovaara P, Palva I, Pettersson R F, Kääriäinen L
Nucleic Acids Res. 1981 Jul 24;9(14):3403-17. doi: 10.1093/nar/9.14.3403.
The 18S defective interfering RNA of Semliki Forest virus has been reverse transcribed to cDNA, which was shown to be heterogeneous by restriction enzyme analysis. After transformation to E.coli, using pBR322 as a vector, two clones, pKTH301 and pKTH309 with inserts of 1.7 kb and 2 kb, were characterized, respectively. The restriction maps of the two clones were different but suggested that both contained repeating units. At the 3' terminus, pKTH301 had preserved 106 nucleotides and pKTH309 102 nucleotides from the 3' end of the viral 42S genome. The conserved 3' terminal sequence was joined to a different sequence in the two clones, and these sequences were not derived from the region coding for the viral structural proteins. The DI RNAs represented by the two clones are generated from the viral 42S RNA by several noncontinuous internal deletions, since the largest colinear regions with 42S RNA are 320 nucleotides in pKTH301, and 430 and 340 nucleotides in pKTH309. All these fragments had unique RNase T1 oligonucleotide fingerprints, suggesting that they were derived from different regions of 42S RNA.
塞姆利基森林病毒的18S缺陷干扰RNA已被逆转录成cDNA，经限制性内切酶分析显示其具有异质性。以pBR322为载体转化大肠杆菌后，分别鉴定出两个克隆，pKTH301和pKTH309，其插入片段分别为1.7 kb和2 kb。这两个克隆的限制性图谱不同，但表明两者都含有重复单元。在3'末端，pKTH301从病毒42S基因组的3'端保留了106个核苷酸，pKTH309保留了102个核苷酸。保守的3'末端序列在两个克隆中与不同的序列相连，并且这些序列并非来自编码病毒结构蛋白的区域。由这两个克隆代表的缺陷干扰RNA是通过几个不连续的内部缺失从病毒42S RNA产生的，因为与42S RNA的最大共线区域在pKTH301中为320个核苷酸，在pKTH309中为430和340个核苷酸。所有这些片段都具有独特的核糖核酸酶T1寡核苷酸指纹图谱，表明它们来自42S RNA的不同区域。
