Asf1はヒストンのカップルのためのラブシートです
1Department of Carcinogenesis, Science Park Research Division, M.D. Anderson Cancer Center, Smithville, TX 78957, USA.
Cell
|November 4, 2006
まとめ
ヒストンチャペロンAsf1がヒストンH3/H4と結合する最初の結晶構造は,チャペロンが核細胞分解をどのように助けるかを明らかにしています. Asf1はテトラメア形成を阻害し,ヒストンH4の構成を変化させます.
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
- エピジェネティクス エピジェネティクス
背景:
- ヒストンチャペロンは,DNAの複製と修復に不可欠です.
- 核子の分解は,染色体調節の重要なステップです.
- チャペロンとヒストンの相互作用を理解することは,クロマチンの動態学にとって不可欠です.
研究 の 目的:
- ヒストンチャペロン (Asf1) がH3/H4ヘテロジマーに結合した最初の結晶構造を決定する.
- ヒストンチャペロンが核細胞分解を促進するメカニズムを解明する.
- ヒストン-チャペロン相互作用の構造的基礎についての洞察を得るために.
主な方法:
- X線結晶グラフィーです.
- タンパク質構造の決定 タンパク質構造の決定
- バイオケミカルアッセイ
主要な成果:
- H3/H4ヘテロダイマーと複合したAsf1の結晶構造が決定されました.
- Asf1は, (H3/H4) 2テトラメルの形成を物理的に防ぐことが示されました.
- ヒストンH4のC端は,Asf1.1と結合すると,重要な形状変化を経験します.
結論:
- この構造は,核粒子の分解におけるAsf1の役割の分子基盤を提供する.
- Asf1はゲートキーパーとして機能し,ヒストンテトラメア形成を制御します.
- チャペロン結合時にヒストンの形状の変化は,クロマチンの改造に不可欠です.
関連する概念動画
02:54Nucleosome Remodeling
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Nucleosome remodeling complex
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Nucleosome remodeling complex
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02:32Histone Modification
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02:30Histone Variants at the Centromere
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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...
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...