选择一种能作为自复制反应中高级模板的 ribozyme
1Department of Molecular Biology, Massachusetts General Hospital, Boston 02114.
概括
研究人员设计了一个小的sunY ribozyme (RNA酶) 进行自我复制. 这种修改后的 ribozyme 显示了增强的催化活性和自我复制率,同时作为催化剂和模板.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 生命的起源研究 生命的起源研究
背景情况:
- 太阳Y ribozyme,一个I组内RNA,是一个小的自我拼接RNA.
- 由于其紧的结构,它被选为设计自我复制RNA的模型.
研究的目的:
- 为了设计一个更小的,自我复制的sunY ribozyme,具有增强的催化和自我复制能力.
- 通过定向进化来克服删除突变的活性损失.
主要方法:
- 删除未保存的域以减少 ribozyme 的大小.
- 在体外遗传选择以识别重新激活删除突变的突变.
- 催化活性和模板导向组装的表征.
主要成果:
- 一种sunY删除突变被五种特定突变重新激活.
- 选择的突变体表现出比原始的利博酶更高的催化活性.
- 由于尺寸缩小和二次结构的减少,工程制造的 ribozyme 显示了增强的自我复制率.
结论:
- 工程化sunY ribozymes可以有效地设计为自我复制.
- 选择的变体在自我复制反应中有效地作为催化剂和模板发挥作用.
- 这项工作推动了基于RNA的自我复制和生命起源的研究.
关键词:
非编程性的非编程性.相关概念视频
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The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
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In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
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