t7 RNAポリメラーゼによる基板選択の構造的基礎
Dmitry Temiakov1, Vsevolod Patlan, Michael Anikin
1Morse Institute for Molecular Genetics, Department of Microbiology, SUNY Health Science Center, 450 Clarkson Avenue, Brooklyn, New York 11203, USA.
Cell
|March 16, 2004
まとめ
RNAポリメラーゼ (RNAP) は,DNAポリメラーゼとは異なり,開かれた形状の基板を選択します. この発見は,触媒活性化前の基板選択のための新しいメカニズムを明らかにし,RNAP全体で潜在的に普遍的です.
科学分野:
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
- バイオケミストリー バイオケミストリー
背景:
- ヌクレオチドポリメラーゼは,DNA複製と転写の信頼性にとって極めて重要です.
- ポリIDNAポリメラーゼにおける基板選択は,開いた形状から閉じた形状への移行と関連しています.
- DNAポリメラーゼにおける基板選択の決定因子は,閉じた状態と関連しています.
研究 の 目的:
- シングルサブユニットRNAポリメラーゼ (RNAP) で基板選択メカニズムが保存されているかどうかを調査する.
- T7 RNAP延伸複合体の構造を,受信する基板アナログで決定する.
主な方法:
- T7 RNAP延長複合体の構造を決定するX線結晶学.
- オープンコンフォーメーションにおける基板結合の構造分析.
- マルチサブユニットRNAPのモデリング.
主要な成果:
- T7RNAPは,DNAポリメラーゼとは異なり,基板をオープンな形状で結合する.
- 基板結合は,開いた状態のテンプレートベースとベースペアリングを伴う.
- タイロシン639 (Tyr639) は,リボースとデオキシリボース基板を区別しています.
結論:
- RNAPにおける基質の選択は,触媒的に活性な形状へのイソメリゼーションの前に起こります.
- このメカニズムは,核酸ポリメラーゼにおける基板選択のための新しい経路を表しています.
- このメカニズムは,マルチサブユニット形態を含むすべてのRNAPにわたって保存されている可能性が示唆されています.
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
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...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
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...
Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
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...


