ヒストンマークH3K36me3は,MutSαとの相互作用を通じて,ヒトDNA不一致修復を調節する
Feng Li1, Guogen Mao, Dan Tong
1Graduate Center for Toxicology, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40506, USA.
Cell
|April 30, 2013
まとめ
エピジェネティックヒストンマークであるH3K36me3は,DNA不一致修復タンパク質を生体内クロマチンに誘導する. この発見は,MMR遺伝子変異が欠けているがんにおけるマイクロサテライトの不安定性を説明する.
科学分野:
- エピジェネティクス エピジェネティクス
- 分子生物学は分子生物学である.
- がん生物学 がん生物学
背景:
- DNAミスマッチ修復 (MMR) は,複製の忠実性にとって極めて重要です.
- ヒトのMMRのインビボメカニズムは,依然としてほとんど不明である.
- マイクロサテライトの不安定性 (MSI) は,MMR欠乏症の特徴であり,がんにおいてしばしば観察される.
研究 の 目的:
- 人間のDNA不一致修復のインビボメカニズムを解明する.
- MMRの採用におけるエピジェネティック・モディフィケーションの役割を調査する.
- 検出可能なMMR遺伝子変異のないがんにおけるMSIの原因を説明するために.
主な方法:
- ヒストンマークとMMRタンパク質の相互作用を in vivoで調査した.
- クロマチン免疫プレシピテーションと遺伝子解析を活用した.
- SETD2メチルトランスフェラーゼが欠けている細胞を調べました.
主要な成果:
- エピジェネティックヒストンマークH3K36me3は,hMutSα複合体をhMSH6 PWWPドメイン経由でクロマチンに直接勧誘する.
- G1および初期のS段階におけるH3K36me3濃縮は,DNA複製の前にhMutSαの存在を保証する.
- SETD2欠乏細胞はMSIと変異頻度の増加を示し,MMR欠乏症のフェノタイプを反映しています.
結論:
- ヒストンマークH3K36me3は,MMRタンパク質をインビヴォで募集するのに不可欠です.
- この表遺伝子規制は,MMRの監視のためのメカニズムを提供します.
- この研究は,ワイルド型MMR遺伝子を持つがんにおけるMSIのパラドックスを解決している.
関連する概念動画
Mismatch Repair
Overview
Histone 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
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Spreading of Chromatin Modifications
The histone proteins in the nucleosomes are post-translationally modified (PTM) to increase or decrease access to DNA. The commonly observed PTMs are methylation, acetylation, phosphorylation, and ubiquitination of lysine amino acids in the histone H3 tail region. These histone modifications have specific meaning for the cell. Hence, they are called "histone code". The protein complex involved in histone modification is termed as "reader-writer" complex.
Writers
The writer is an enzyme that can...
Writers
The writer is an enzyme that can...
Mismatch Repair
Overview
Histone 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,...
Mismatch Repair
Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...


