Pirtle R M, Pirtle I L, Inouye M
J Biol Chem. 1980 Jan 10;255(1):199-209.
The sequence of 92 nucleotides at the 3' end of the mRNA which codes for the lipoprotein of the outer membrane of Escherichia coli has been determined to be GCUAACCAGCGUCUGGACAACAUGGCUACUAAAUACCGCAAGUAAUAGUACCUGUGAAGUGAAAAAUGGCGCACAUUGUGCGCCAUUUUUUUOH. This sequence includes the 50 nucleotides comprising the 3' untranslated region of the mRNA and contains codons for 14 amino acids at the COOH-terminal of the lipoprotein. In addition, the nucleotide sequences of all oligonucleotides derived from complete ribonuclease T1 and ribonuclease A digestions of the lipoprotein mRNA were established. These oligonucleotides were assigned to portions of the known amino acid sequence as well as the 5' untranslated and 3' untranslated regions of the mRNA molecule. With the use of the genetic code, these oligonucleotide sequences served to establish 94% of the mRNA sequence. The lipoprotein mRNA can be deduced to be 322 nucleotides in length. All three translation termination codons (UAA, UAG, and UGA) were found in phase with the coding region of the mRNA. The region at the 3' end of the mRNA showed unusual resistance to partial degradation, and the partial fragments from this region had anomalous mobilities in two-dimensional gels, even under denaturing conditions. This indicates that there is a very stable hairpin stem-and-loop structure at the 3' end. This hairpin structure exhibits all the structural elements implicated in termination of transcription in, prokaryotes.
编码大肠杆菌外膜脂蛋白的mRNA 3'端92个核苷酸的序列已确定为GCUAACCAGCGUCUGGACAACAUGGCUACUAAAUACCGCAAGUAAUAGUACCUGUGAAGUGAAAAAUGGCGCACAUUGUGCGCCAUUUUUUUOH。该序列包括构成mRNA 3'非翻译区的50个核苷酸，并在脂蛋白的COOH末端包含14个氨基酸的密码子。此外，还确定了脂蛋白mRNA经核糖核酸酶T1和核糖核酸酶A完全消化后得到的所有寡核苷酸的核苷酸序列。这些寡核苷酸被分配到已知氨基酸序列的部分以及mRNA分子的5'非翻译区和3'非翻译区。利用遗传密码，这些寡核苷酸序列确定了94%的mRNA序列。可推断脂蛋白mRNA长度为322个核苷酸。所有三个翻译终止密码子（UAA、UAG和UGA）均与mRNA的编码区同相位。mRNA 3'端区域对部分降解表现出异常抗性，该区域的部分片段在二维凝胶中具有异常迁移率，即使在变性条件下也是如此。这表明在3'端存在非常稳定的发夹茎环结构。这种发夹结构展现出原核生物转录终止中涉及的所有结构元件。
