相关实验视频
Updated: Jun 8, 2026

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Novel RNA-Binding Proteins Isolation by the RaPID Methodology
Published on: September 30, 2016
通过A. fulgidus Piwi蛋白质对指导RNA进行5'-end 特定识别的结构基础
Jin-Biao Ma1, Yu-Ren Yuan, Gunter Meister
1Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
Nature
|April 1, 2005
概括
阿尔戈纳特蛋白中的PIWI域对RNA干扰 (RNAi) 基因调节至关重要. 这项研究揭示了Piwi-RNA复合体的晶体结构,详细说明了导向RNA结合如何促进信使RNA标识和分裂.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- RNA干扰 (RNAi) 是一种特定序列的基因调节机制.
- 由RNA诱导的沉默复合体 (RISC) 调解RNAi,涉及阿尔戈诺特蛋白和指导RNA.
- 阿尔戈诺特的PIWI域对于RISC的内核酶活性至关重要.
研究的目的:
- 为了确定与双链RNA结合的Archaeoglobus fulgidus Piwi蛋白质的晶体结构.
- 识别指导RNA结合口袋并了解其在信使RNA目标识别中的作用.
- 阐明指导RNA介导的标结合和裂变部位定位的机制.
主要方法:
- 考古巨 (Archaeoglobus fulgidus Piwi) 蛋白质的X射线晶体学复杂化与双链RNA.
- 在人类Ago2中保存残留物的局部定向突变发生2.
主要成果:
- 晶体结构显示了一个保存的基本口袋,定了指导RNA的酸化5'端.
- 第一个导向RNA核酸是不配对的,并堆叠在氨酸上,而随后的核酸形成双重.
- 影响人类Ago2中5'酸盐结合的突变减少了mRNA裂变活性.
- 导向RNA的5'端作为目标mRNA配对的核化部位.
结论:
- 皮维-RNA结构为RNAi的分子基础提供了关键的见解.
- 导向RNA的5'端对于目标识别至关重要,并决定mRNA分裂部位.
- 这些结构信息有助于我们对基因沉默机制的理解.
相关概念视频
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...
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...
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Leaky Scanning
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piRNA - Piwi-interacting RNAs
PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
Pre-mRNA Processing: Modification of pre-mRNA Ends
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps the cell...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps the cell...
Nucleic Acid Structure
The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group on the ribose's second carbon and a hydrogen on the deoxyribose's second carbon. The phosphate residue attaches to the hydroxyl group of the 5′ carbon of one sugar and the hydroxyl group of the 3′ carbon of the sugar of the next nucleotide, which forms a 5′ to 3′ phosphodiester linkage.
DNA Structure
DNA has a double-helix structure. The...
DNA Structure
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