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Updated: Jun 18, 2026

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Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
RNAポリマースリボ酵素の触媒核の結晶構造
David M Shechner1, Robert A Grant, Sarah C Bagby
1Whitehead Institute for Biomedical Research and Howard Hughes Medical Institute, 9 Cambridge Center, Cambridge, MA 02142, USA.
まとめ
RNA世界におけるRNA複製に不可欠な,迅速に作用するRNAリガゼリボ酵素の結晶構造は,三脚のような構造を明らかにする. この構造は,タンパク質ポリメラーゼに似た触媒メカニズムを示唆し,生命の初期についての理解を深めています. キーワード:RNAリガゼリボエンザイム,RNA複製,RNA世界,タンパク質ポリメラーゼ.
科学分野:
- 生命の起源の研究 生命の起源の研究
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
背景:
- RNA世界仮説は,RNAがDNAとタンパク質の前に遺伝物質と触媒の両方として機能したと仮定しています.
- リボ酵素 (触媒性RNA分子) によるRNAの複製は,自給自足のRNA世界にとって根本的な要件である.
- クラスIRNAリガゼは,高触媒率の人工リボ酵素であり,RNA複製に必要なポリメラーゼ活性に近似しています.
研究 の 目的:
- クラスIRNAリガゼリボジームの3次元構造を解明する.
- このリボ酵素の触媒作用の構造的基礎を理解するために.
- 決定された構造に基づいたRNA複製触媒のモデルを提案する.
主な方法:
- X線結晶学を用いて,クラスIのRNAリガゼの構造を3.0アングストームの解像度で決定した.
- 構造分析は,リボ酵素の構造,活性部位の組織,および結合交差点での相互作用に焦点を当てました.
主要な成果:
- 結晶構造は,3つの構造的足が結合部位の近くに収束するユニークな"三脚"構造を明らかにしています.
- 未配列のRNAセグメントは,マイナー・グルーブ相互作用を通じて三脚の脚架と相互作用し,活性部位を組織する.
- 結合交差点における特定の核塩基とリン酸塩の位置付けは,タンパク質ポリメラーゼに類似する触媒機構を示唆する.
結論:
- 決定された構造は,リボ酵素によるRNA複製のメカニズムに関する重要な洞察を提供します.
- この発見は,前生物時代のRNA複製の実現可能性とRNAベースの生命の可能性を裏付けている.
- タンパク質ポリメラーゼとの構造的類似性は,RNAとタンパク質触媒の間の潜在的な進化的リンクを提供します.
関連する概念動画
RNA Structure
Overview
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...
RNA Structure
The basic structure of RNA consists of a string of ribonucleotides attached by phosphodiester bonds. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA) involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three...
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA) involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three...
RNA Structure
Overview
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form complex secondary and tertiary structures. Such structures play essential roles in the regulation of transcription and translation.
Different Types of RNA Have the Same Basic Structure
There are three main types of ribonucleic acid (RNA): messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). All three RNA types consist of a...
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...
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...

