異常なmRNAシドノット構造は,タンパク質翻訳抑制剤によって認識されます
1Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218.
Cell
|May 19, 1989
まとめ
E. coliのアルファオペロンmRNAに結合するリボソームタンパク質S4は,ダブルシドオノット構造を含むことが確認されています. S4によるこのRNA構造の安定化は,おそらく翻訳抑制を説明している.
科学分野:
- 分子生物学は分子生物学である.
- RNA 構造 RNA 構造
- バクテリアの遺伝子規制
背景:
- リボソームタンパク質S4は,E. coliのアルファオペロンにおけるリボソームタンパク質の翻訳を調節する.
- S4は,特異的に翻訳開始部位にあるRNA断片を結合する.
- 以前の研究では,S4結合部位の擬結構造が示唆されていた.
研究 の 目的:
- S4結合部位の提案された擬似結構造を体系的にテストし,確認する.
- S4による翻訳抑制におけるRNA構造の役割を調査する.
主な方法:
- 補償的な塩基対変化を生み出すために,サイト指向型変異を生成する.
- 変異の影響を測定するためのS4結合測定法.
- RNA構造マッピング実験.
主要な成果:
- 提案されたS4結合部位の仮結構造は確認された.
- さらに2つの予期せぬ相互作用が,擬似結の内部で特定されました.
- 異常な"ダブルシドウノット"構造が特徴付けられ,上流のヘアピンと下流の配列を結びました.
結論:
- ダブルシドオノットRNA構造はS4結合に不可欠である.
- この二重シドオノットのS4による安定化は,アルファオペロンの翻訳抑制を説明する.
- この研究は,バクテリアの翻訳制御のための詳細な構造的基礎を提供します.
関連する概念動画
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.
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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
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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,...


