结构引导的工程RNA酶 ribozymes的区域选择性
Jason N Pitt1, Adrian R Ferré-D'Amaré
1Molecular and Cellular Biology Program, University of Washington, Seattle, Washington 98195, USA.
Journal of the American Chemical Society
|February 18, 2009
概括
RNA复合体中的结构差异决定了 ribozymes 是否形成 2'-5' 或 3'-5' RNA 链接. 这一发现对理解RNA世界起源和RNA合成的 ribozyme 工程产生了影响.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 天体生物学 天体生物学
背景情况:
- 酶催化RNA合成是RNA世界假设的关键,但自然RNA聚合酶尚未被发现.
- 实验室内选择已经产生了能够进行RNA结合的 ribozymes,经常产生2-5"的基键,而不是传统的3-5"链接.
研究的目的:
- 阐明2-5和3-5RNA结合酶 рибо酶中区域选择性的结构基础.
- 研究基质模板双重几何在控制RNA结合结果中的作用.
主要方法:
- 确定产品模板二重复的2-5RNA结合酶 ribozyme (II类结合酶) 的晶体结构,并将其与3-5结合酶 ribozyme (L1结合酶) 的结构进行比较.
- 通过在II类和L1类联酶之间交换基质模板双重区域来构建嵌合式 ribozymes.
- 在催化RNA结合过程中评估了嵌合式 рибо酶的区域选择性.
主要成果:
- 晶体结构在结合结处显示出明显的双重几何:在II类结合酶中,一对G x A对被接着,而在L1结合酶中则是G x U波动.
- 化学 ribozymes 证明了基质模板复合体,而不是催化核心,决定了区域选择性.
- 具有II类双重体的L1链酶在2-5键合成中增加了30倍,而具有L1双重体的II类链酶仅形成3-5键.
结论:
- 基质模板复合体的局部几何是 ribozyme-catalyzed RNA 结合中的区域选择性的主要决定因素.
- 这些发现为RNA合成的演化提供了洞察力,以及设计具有特定结合活动的 ribozymes 的潜力.
相关概念视频
Ribozymes
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.
Ribozymes can be...
Ribozymes can be...
Ribozymes
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.
Ribozymes can be...
Ribozymes can be...
Riboswitches
Riboswitches are non-coding mRNA domains that regulate the transcription and translation of downstream genes without the help of proteins. Riboswitches bind directly to a metabolite and can form unique stem-loop or hairpin structures in response to the amount of the metabolite present. They have two distinct regions – a metabolite-binding aptamer and an expression platform.
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
Types of RNA
Overview
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
Translational Regulation
Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...
RNA Interference
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...


