ヒストンH2A-H2Bの認識の構造的基礎 基本的チャペロンによる認識
Maria Hondele1, Tobias Stuwe, Markus Hassler
1Department of Physiological Chemistry, Butenandt Institute and LMU Biomedical Center, Faculty of Medicine, Ludwig Maximilians University of Munich, Butenandtstrasse 5, 81377 Munich, Germany.
Nature
|May 24, 2013
まとめ
The Facilitates Chromatin Transcription (FACT) コンプレックス構造は,H2A-H2Bヒストンを結合する方法を示しています. このメカニズムは,FACTが核細胞を再編成し,DNA転写,複製,修復プロセスを強化する方法を説明しています.
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:
- クロマチンの転写を促進する (FACT) は重要なヒストンのチャペロンです.
- FACTは,DNAの転写,複製,修復のために核細胞を再編成します.
- FACTのH2A-H2B認識の構造的根拠は,以前は知られていなかった.
研究 の 目的:
- FACTのH2A-H2Bヒストン二重体との相互作用の構造的基礎を解明する.
- FACT結合が核細胞構造とDNAアクセシビリティにどのように影響するかを理解する.
- FACT ヘテロダイメリゼーションドメインの構造を決定する.
主な方法:
- H2A-H2B.とのSpt16M (FACT成分) の構造を決定するためのX線結晶学.
- 構造的発見を検証し,ヒストンの相互作用を分析するために生化学および体内の測定法.
- FACTヘテロダイメリゼーション領域の構造分析.
主要な成果:
- H2A-H2Bヘテロダイマーに結合したFACTチャペロンドメインSpt16Mの結晶構造を明らかにした.
- Spt16Mにおける新しい"Uターン"モチーフを特定し,H2A-H2Bヒストンダイマーと相互作用した.
- FACT結合が,ヒストン-DNAの接触を再構成することによって,核細胞の"呼吸"を促進することを示した.
結論:
- 決定された構造は,FACTの重要な監視機能に関する高解像度の洞察を提供します.
- FACTのH2A-H2B認識のメカニズムは,核細胞の再編成におけるその役割を説明する.
- この研究は,FACTが核細胞の再編成を必要とする酵素の活動を促進する方法を明らかにしています.
関連する概念動画
01:12The Nucleosome Core Particle
Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
02:10The Nucleosome Core Particle
Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
02:32Histone Modification
The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
02:32Histone Modification
The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
01:19The Nucleosome
Human DNA is almost two meters long. However, it is compressed inside a tiny nucleus measuring only a few microns in diameter. To make this degree of compaction possible, DNA is organized into several sequential levels so that it can fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
02:33The Nucleosome
DNA in a human cell is almost 2m long and it is packed inside a tiny nucleus that is only a few microns in diameter. The level of compaction of DNA inside the nucleus is astonishing. It is organized into several sequentially higher levels of compaction to fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...