Harris T J
Nucleic Acids Res. 1979 Dec 11;7(7):1765-85. doi: 10.1093/nar/7.7.1765.
Foot and mouth disease virus RNA has been treated with RNase H in the presence of oligo (dG) specifically to digest the poly(C) tract which lies near the 5' end of the molecule (10). The short (S) fragment containing the 5' end of the RNA was separated from the remainder of the RNA (L fragment) by gel electrophoresis. RNA ligase mediated labelling of the 3' end of S fragment showed that the RNase H digestion gave rise to molecules that differed only in the number of cytidylic acid residues remaining at their 3' ends and did not leave the unique 3' end necessary for fast sequence analysis. As the 5' end of S fragment prepared form virus RNA is blocked by VPg, S fragment was prepared from virus specific messenger RNA which does not contain this protein. This RNA was labelled at the 5' end using polynucleotide kinase and the sequence of 70 nucleotides at the 5' end determined by partial enzyme digestion sequencing on polyacrylamide gels. Some of this sequence was confirmed from an analysis of the oligonucleotides derived by RNase T1 digestion of S fragment. The sequence obtained indicates that there is a stable hairpin loop at the 5' terminus of the RNA before an initiation codon 33 nucleotides from the 5' end. In addition, the RNase T1 analysis suggests that there are short repeated sequences in S fragment and that an eleven nucleotide inverted complementary repeat of a sequence near the 3' end of the RNA is present at the junction of S fragment and the poly(C) tract.
口蹄疫病毒RNA已在寡聚（dG）存在的情况下用核糖核酸酶H处理，以特异性消化位于分子5'端附近的聚（C）序列（10）。通过凝胶电泳将含有RNA 5'端的短（S）片段与RNA的其余部分（L片段）分离。RNA连接酶介导的S片段3'端标记表明，核糖核酸酶H消化产生的分子仅在其3'端剩余的胞苷酸残基数量上有所不同，并且没有留下快速序列分析所需的独特3'端。由于从病毒RNA制备的S片段的5'端被VPg阻断，因此从不含该蛋白质的病毒特异性信使RNA制备S片段。使用多核苷酸激酶在5'端对该RNA进行标记，并通过聚丙烯酰胺凝胶上的部分酶消化测序确定5'端70个核苷酸的序列。通过对S片段核糖核酸酶T1消化产生的寡核苷酸的分析，证实了该序列的一部分。获得的序列表明，在距5'端33个核苷酸的起始密码子之前，RNA的5'末端存在一个稳定的发夹环。此外，核糖核酸酶T1分析表明，S片段中存在短重复序列，并且在S片段与聚（C）序列的交界处存在RNA 3'端附近序列的11个核苷酸反向互补重复序列。
