不寻常的mRNA伪结结构被蛋白质翻译抑制剂识别出来
1Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218.
Cell
|May 19, 1989
概括
证实了与大肠杆菌α操作子mRNA结合的S4核糖体蛋白涉及双重伪结结构. 这种RNA结构由S4稳定可能解释了转化抑制.
科学领域:
- 分子生物学分子生物学
- 结构RNA结构RNA结构
- 细菌基因调节的细菌基因调节
背景情况:
- 核糖体蛋白S4调节了核糖体蛋白在大肠杆菌α操作中的翻译.
- S4在转化启动部位特别结合一个RNA片段.
- 以前的研究表明,S4结合部位的伪结结构.
研究的目的:
- 系统地测试和确认S4结合部位的拟议伪结结构.
- 研究RNA结构在S4的转化抑制中的作用.
主要方法:
- 局部定向的突变发生,以产生补偿性的基对变化.
- 用S4结合测试来测量突变的影响.
- 进行RNA结构映射实验.
主要成果:
- 证实了S4结合部位的拟议伪结结构.
- 在伪结中发现了两个额外的,意想不到的相互作用.
- 标志着一个不寻常的"双伪结"结构,将上游的发针与下游的序列联系起来.
结论:
- 双重伪结RNA结构对于S4结合至关重要.
- 通过S4稳定这种双伪结,可以解释alpha操作子的转化抑制.
- 这项研究为细菌的转化控制提供了详细的结构基础.
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...
Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
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...
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...
Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...


