EMERGENCE OF A REPLICATING SPECIES FROM AN IN-VITRO RNA EVOLUTION REACTION
EMERGENCE OF A REPLICATING SPECIES FROM AN IN-VITRO RNA EVOLUTION REACTION
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DOI：
10.1073/pnas.91.13.6093
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发表时间：
1994-06-21
影响因子：
11.1
通讯作者：
JOYCE, GF
中科院分区：
文献类型：
--
作者：
BREAKER, RR;JOYCE, GF
自我维持的序列复制技术允许在体外等温扩增DNA和RNA分子。该方法减轻了逆转录酶和DNA依赖性RNA聚合酶扩增特定核酸序列的活性。我们已经修改了这个方案，允许选择性扩增催化特定化学反应的RNA。在采用这种改良系统的体外RNA进化实验中，出现了一类独特的“自私”RNA，并复制到排除预期RNA。这类自私分子的成员被称为RNA Z，尽管它们不能催化目标化学反应，但它们能有效地扩增。它们的扩增需要逆转录酶和RNA聚合酶的作用，并涉及DNA和RNA复制中间体的合成。RNA Z的扩增机制涉及形成DNA发夹，其作为RNA聚合酶转录的模板。这种排列连接DNA的两条链，导致产生含有嵌入的RNA聚合酶启动子序列的RNA转录物。
The technique of self-sustained sequence replication allows isothermal amplification of DNA and RNA molecules in vitro. This method relief on the activities of a reverse transcriptase and a DNA-dependent RNA polymerase to amplify specific nucleic acid sequences. We have modified this protocol to allow selective amplification of RNAs that catalyze a particular chemical reaction. During an in vitro RNA evolution experiment employing this modified system, a unique class of ''selfish'' RNAs emerged and replicated to the exclusion of the intended RNAs. Members of this class of selfish molecules, termed RNA Z, amplify efficiently despite their inability to catalyze the target chemical reaction. Their amplification requires the action of both reverse transcriptase and RNA polymerase and involves the synthesis of both DNA and RNA replication intermediates. The proposed amplification mechanism for RNA Z involves the formation of a DNA hairpin that functions as a template for transcription by RNA polymerase, This arrangement links the two strands of the DNA, resulting in the production of RNA transcripts that contain an embedded RNA polymerase promoter sequence.