関連する実験動画

Updated: Jun 28, 2026

Analyzing and Building Nucleic Acid Structures with 3DNA

Analyzing and Building Nucleic Acid Structures with 3DNA

Published on: April 26, 2013

T7エンドヌクレアゼIによるホリデイ・ジャンクション解離の構造的基礎

Jonathan M Hadden¹, Anne-Cécile Déclais, Stephen B Carr

¹Astbury Centre for Structural Molecular Biology, Institute of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.

|September 18, 2007

まとめ

ファージT7内核酵素Iは,DNA修復と遺伝的多様性にとって極めて重要な4つのDNA結合を解除する. その結晶構造は,枝分かれしたDNA構造に選択的に結合することを保証する誘導的適合機構を明らかにします.

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:

4方向 (ホリデー) のDNA結合は,同類の再結合における重要な中間物質である.
ホモログ的再結合は,DNA修復と遺伝的多様性の生成に不可欠である.
交差点解消酵素は,これらの分岐DNA構造を選択的に処理する核酸である.

研究の目的:

結合解消酵素における構造選択性のメカニズムを解明する.
ファグT7内核酵素Iと四方向DNA結合の相互作用に関する構造的洞察を提供するため.

主な方法:

X線結晶学を用いて,ファグT7エンドヌクレアゼIの構造を決定した.
酵素は合成四方向DNA結合で複合的に結晶化されました.

主要な成果:

結晶構造は,結合時に酵素とDNAの接合点の両方に有意な誘導的適合を示しています.
二次酵素は,2つの結合チャネルを利用して,7つのヌクレオチドを介してDNAの骨幹と相互作用します.
これらの相互作用は,交差点の腕の空間的配置を正確に測定し,選択性を確保します.

結論:

この研究は,DNA結合解像度のメカニズムの最初の構造的基礎を提供します.
ファージT7内核酵素Iは,酵素構造とDNAの誘導された構成変化の組み合わせによって特異性を達成します.
この詳細な構造的な理解は,DNA修復と再結合の経路を理解するために不可欠です.

さらに関連する動画

X-Ray Crystallography to Study the Oligomeric State Transition of the Thermotoga maritima M42 Aminopeptidase TmPep1050

X-Ray Crystallography to Study the Oligomeric State Transition of the Thermotoga maritima M42 Aminopeptidase TmPep1050

Published on: May 13, 2020

DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation

DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation

Published on: December 29, 2021

関連する概念動画

Structural Protein Function

Structural Protein Function

Structural proteins are a category of proteins responsible for functions ranging from cell shape and movement to providing support to major structures such as bones, cartilage, hair, and muscles. This group includes proteins such as collagen, actin, myosin, and keratin.
Collagen, the most abundant protein in mammals, is found throughout the body. In connective tissue, such as skin, ligaments, and tendons, it provides tensile strength and elasticity. In bones and teeth, it mineralizes to form...

ATP Synthase: Mechanism

ATP Synthase: Mechanism

In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased ATP...

ATP Synthase: Structure

ATP Synthase: Structure

ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...

Structural Protein Function

Structural Protein Function

Structural proteins are a category of proteins responsible for functions ranging from cell shape and movement to providing support to major structures such as bones, cartilage, hair, and muscles. This group includes proteins such as collagen, actin, myosin, and keratin.
Collagen, the most abundant protein in mammals, is found throughout the body. In connective tissue, such as skin, ligaments, and tendons, it provides tensile strength and elasticity. In bones and teeth, it mineralizes to form...

Keto–Enol Tautomerism: Mechanism

Keto–Enol Tautomerism: Mechanism

The keto and enol forms are known as tautomers and they constantly interconvert (or tautomerize) between the two forms under acid or base catalyzed conditions. Both the reactions involve the same steps—protonation and deprotonation— although in the reverse order.

The Proteasome Structure

The Proteasome Structure

The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...