相关实验视频
Updated: Jul 11, 2026

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Transcription Start Site Mapping Using Super-low Input Carrier-CAGE
Published on: June 26, 2019
通过CCA添加酶转移RNA成熟的机制,而不使用寡核酸模板
1Department of Molecular Biophysics and Biochemistry,Yale University, New Haven, Connecticut 06520, USA.
Nature
|August 6, 2004
概括
转移RNA核样转移酶 (CCA添加酶) 将必要的CCA核酸添加到没有模板的tRNA中. 这项研究揭示了这一关键酶的晶体结构和机制.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- 转移RNA核样转移酶 (CCA添加酶) 对于tRNA的成熟和修复至关重要.
- 这些酶将必需的3' CCA核酸添加到tRNA中.
- 在CCA添加酶的模板聚合机制仍然不太了解.
研究的目的:
- 通过tRNA核基转移酶阐明模板独立的CCA添加的结构基础.
- 了解这些酶的基质特异性和歧视机制.
主要方法:
- 使用X射线晶体学来确定Archaeoglobus fulgidus tRNA核基转移酶的结构.
- 分析了具有tRNA和RNA双重模仿的复合体.
- 具有输入核酸5'-三酸盐的三级复合物被描述为特征.
主要成果:
- 确定了与tRNA复合的A. fulgidustRNA核样转移酶的晶体结构.
- 确定了一个单个核酸结合口袋,对CTP和ATP的特异性是由Arg 224和tRNA骨干酸盐决定的.
- 该酶排除了UTP和GTP由于非互补相互作用.
- 在CTP和ATP之间的区别和终结是由绑定位的形状变化调节的,因为tRNA的3'端延长.
结论:
- 该研究提供了对模板独立的CCA加法机制的结构性见解.
- 这些发现解释了CTP和ATP的特异性以及终止过程.
- 这项工作推动了我们对tRNA生物学和酶机制的理解.
相关概念视频
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...
Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
RACE - Rapid Amplification of cDNA Ends
Rapid Amplification of cDNA Ends, or RACE, is one of the most effective methods to obtain a full-length cDNA from an mRNA sequence between a known internal region to the unknown sequence at the 5’ or 3’ end. The unknown region is cloned in the cDNA by a gene-specific primer that binds the known end, and a hybrid primer that attaches a predefined anchor sequence to the unknown end of the cDNA. The sequence in between is amplified by PCR with an anchor primer and a gene-specific primer.
Since the...
Since the...
Types of 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 regulating 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 Performs Diverse...
RNA Performs Diverse...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...

