関連する実験動画
Updated: Aug 15, 2026

06:59
Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
グループIリボ酵素によるRNA触媒の誘導配列の移動
まとめ
リボ酵素は,その内部誘導配列 (IGS) を介して基板を結合することによって,配列特異的なエンドヌクレアースとして機能します. この結合は,分子を触媒核に輸送するために不可欠な形状の変化を誘導します.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- RNAのカタリシス
背景:
- 自己結合RNAから派生したリボ酵素は,エンドヌクレアース活性を示す.
- この活動は,内部ガイドシーケンス (IGS) を通して基板結合に依存し,ヘリックスP1.1を形成します.
研究 の 目的:
- Tetrahymena ribozymesの3次元構造を調査するために.
- 基板結合と触媒に伴う構造変化を解明する.
主な方法:
- リボ酵素のサイト固有のフォトクロスリンク.
- IGSの近くをマッピングするためにクロスリンクされた製品の分析.
主要な成果:
- ヘリックスP1におけるIGSの5'端は,既存の構造モデルを支える,保存されたベース (P4-P5) の近くに位置していた.
- クロスリンクされたリボ酵素は,触媒的活性を維持した.
- 非ペアリングされたIGSもクロスリンクしたが,異なる位置で,形状の柔軟性を示した.
結論:
- サブストラット結合は,リボ酵素における重要な形状変化 (誘導適合) を誘導する.
- この形状の柔軟性は,基板を触媒コアに運ぶための鍵です.
- RNAの大きな形状の変化に対する能力は,リボソームとスプライソームのRNA基盤を説明する可能性がある.
関連する概念動画
Eukaryotic RNA Polymerases
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
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
DNA has a double-helix structure. The...

