传递 RNA 盖结构的双重功能在酵母酵母中的多A尾促翻译中
1Gene Expression Programme, European Molecular Biology Laboratory, Heidelberg, Germany.
Nature
|April 21, 1998
概括
消息传递 RNA 聚甲尾作为转化促进体,将核糖体传递给未加盖的mRNA. 与mRNA盖结构一起,它协同工作,以确保高效的翻译启动和控制.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 传递 RNA (mRNA) 的 3'多A 尾部对于真核生物的翻译启动和调节至关重要.
- 它已被概念化为一个翻译增强剂,增强mRNA5'-cap结构的促进体活性.
- 众所周知,Poly(A) 尾巴长度调制在发育过程中调节翻译.
研究的目的:
- 为了研究多尾在翻译启动中的独立作用.
- 为了确定在核糖体招募中多元A尾和5'-cap结构之间的协同相互作用.
- 阐明这些要素如何确保准确的翻译启动和调节.
主要方法:
- 在Saccharomyces cerevisiae中进行无细胞翻译试验.
- 在Saccharomyces cerevisiae中的体内翻译分析.
- 使用加盖和未加盖的mRNAs,具有不同多元A尾长的比较研究.
主要成果:
- 聚甲尾作为一个独立的翻译促进体,能够将核糖体传递给未加盖的mRNAs.
- 当mRNA争夺核糖体时,单独的帽子和聚甲尾都不足以实现高效的翻译.
- 帽子结构和多个A) 尾部协同作用,促进核糖体的招募和与mRNA 5'端的结合.
结论:
- 聚甲尾在启动翻译中扮演着直接的角色,独立于帽子结构.
- 聚甲尾和5'-cap结构的联合作用对于高效和规律的翻译启动至关重要.
- 这种功能性相互作用确保了正确选择翻译启动密码子和翻译调节器的正确作用.
相关概念视频
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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 to it (7-Methyl guanosine). This 5’ cap helps the...
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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...
Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...


