RNA-PRIMED INITIATION OF MOLONEY MURINE LEUKEMIA-VIRUS PLUS STRANDS BY REVERSE-TRANSCRIPTASE INVITRO
RNA-PRIMED INITIATION OF MOLONEY MURINE LEUKEMIA-VIRUS PLUS STRANDS BY REVERSE-TRANSCRIPTASE INVITRO
复制标题
DOI：
10.1128/jvi.51.1.26-33.1984
复制
发表时间：
1984-01-01
影响因子：
5.4
通讯作者：
CHAMPOUX, JJ
中科院分区：
文献类型：
--
作者：
FINSTON, WI;CHAMPOUX, JJ
构建了包含正链 DNA 合成的莫洛尼鼠白血病病毒起源的 190 个碱基对 DNA-RNA 杂交体，并用作体外逆转录酶的模板引物来源。合成精确地在已知的正链起源处开始。一些起始片段在其 5'' 末端保留核糖核苷酸残基的观察表明，链起始的引物是在 DNA-RNA 杂交体的 RNA 部分降解过程中由 RNase H 留下的 RNA 分子。如果 RNase H 负责产生正确的引物末端，那么它必须具有特定的核酸内切活性，能够识别 RNA 中正链起始的序列。跨越正链起点的 16 个碱基 RNase A 抗性片段也可以作为特异性正链引物 RNA 的来源。显然，一些在内源反应中合成的正链起始片段含有5''核糖核苷酸，这表明用于正链起始的特异性RNA引物也可能在体内逆转录过程中产生。
A 190-base-pair DNA-RNA hybrid containing the Moloney murine leukemia virus origin of plus-strand DNA synthesis was constructed and used as a source of template-primer for the reverse transcriptase in vitro. Synthesis initiated precisely at the known plus-strand origin. The observation that some of the origin fragments retained ribonucleotide residues on their 5'' ends suggests that the primer for chain initiation is an RNA molecule left behind by RNase H during the degradation of the RNA moiety of the DNA-RNA hybrid. If the RNase H is responsible for creating the correct primer terminus, then it must possess a specific endonucleolytic activity capable of recognizing the sequence in the RNA where plus strands are initiated. The 16-base RNase A-resistant fragment which spans the plus-strand origin can also serve as a source of the specific plus-strand primer RNA. Evidently some of the plus-strand origin fragments synthesized in the endogenous reaction contain 5'' ribonucleotides, suggesting that specific RNA primers for plus-strand initiation may be generated during reverse transcription in vivo as well.