Chd1クロモドメインはヒストンH3メチル化とSAGAおよびSLIKに依存するアセチル化を結びつける
Marilyn G Pray-Grant1, Jeremy A Daniel, David Schieltz
1Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA.
Nature
|January 14, 2005
まとめ
研究者らは,Chd1 (クロモ-ATPase/ヘリカーゼ-DNA結合ドメイン1) がメチルヒストンH3に結合することを発見した. この相互作用は,SAGAとSLIKヒストンアセチルトランスフェラーゼ複合体の活動を強化し,遺伝子調節に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- クロマチン生物学 クロマチン生物学
背景:
- ヒストンの翻訳後の改変は,遺伝子調節やDNA修復などの核過程を調節する.
- ヒストンアセチルトランスフェラーゼ (HAT) は,転写活性化における重要な酵素である.
- 酵母SAGAとSLIKは,ヒストンのアセチル化とデウビキチン化に関与する保存されたHAT複合体です.
研究 の 目的:
- SAGAとSLIK複合体の新しい成分を特定する.
- ヒストンの改変経路におけるクロマチンの改造タンパク質の役割を調査する.
- Chd1とヒストンの改変の相互作用を特徴づけるために.
主な方法:
- クロマチンの免疫プレシピテーションに続いて,SAGA/SLIKの成分を特定するための質量スペクトロメトリーが行われます.
- 再結合タンパク質と精製されたヒストンペプチドを用いたインビトロ結合アッセイ.
- 酵母遺伝学と顕微鏡を用いたin vivo研究で,複雑な機能を評価する.
主要な成果:
- クロマチンの改造タンパク質Chd1 (クロモ-ATPase/ヘリカーゼ-DNA結合ドメイン1) は,SAGAとSLIKの成分として特定されました.
- Chd1の1つの染色体は,ライシン4 (H3K4me) のメチル化ヒストンH3を特異的に認識する.
- SLIK複合体は,Chd1のメチル結合クロモドメインに依存するメチル基板の強化されたアセチル化を示す.
結論:
- この研究では,H3K4me.me.を認識する最初の染色体を特定しました.
- Chd1はヒストンのメチル化マークとアセチル化との間の重要なリンクとして機能します.
- 同様の認識特性を持つクロモドメインタンパク質の潜在的サブファミリーが示唆されています.
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Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
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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,...
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