H3K27の脱メチル化は,ポリコンブ募集とH2Aのユビキチネーションを調節する
Min Gyu Lee1, Raffaella Villa, Patrick Trojer
1Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA.
まとめ
人間のUTXタンパク質は,ヒストンH3ライシン27 (H3K27) からメチルマークを除去し,これは重要なエピジェネティックサイレンシングマークである. UTXは,H3K4メチル化をH3K27脱メチル化とリンクし,遺伝子の活性化を図る.
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.
- 遺伝子規制 遺伝子規制
背景:
- ヒストンH3リジン27 (H3K27) メチレーションは,遺伝子サイレンシングに関連した重要な表遺伝子マークです.
- H3K27メチル化を調節する酵素を理解することは,遺伝子発現制御の解読に不可欠です.
研究 の 目的:
- H3K27の脱メチル化に起因するヒトの酵素を特定する.
- 遺伝子転写,特にHOX遺伝子の調節におけるこの酵素の役割を明らかにする.
主な方法:
- H3K27.27におけるUTXの酵素活性を決定するための生化学的分析.
- 遺伝子プロモーターのUTX占有率を評価するためのクロマチン免疫プレシピテーション.
- ヒストンの改変と規制複合体の採用の分析.
主要な成果:
- ヒトUTXは,Jumonji Cファミリーのタンパク質で,di-およびtrimethyl H3K27脱メチラーゼとして識別されました.
- UTXはHOX遺伝子プロモーターに局所化し,ポリコンブ抑制複合体1の募集とヒストンH2Aモノウビキチネーションを調節することにより,それらの転写に影響を与えます.
- UTXはMLL2/3複合体と相互作用し,レチノ酸シグナル伝達中にH3K4メチル化とH3K27脱メチル化を結びつける.
結論:
- UTXは,H3K27.7を積極的にデメチル化することによって,転写活性化に重要な役割を果たします.
- MLL2/3媒介のH3K4メチル化がUTX媒介のH3K27脱メチル化と結合して遺伝子の活性化を行うという協調メカニズムが存在する.
関連する概念動画
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,...
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,...
Epigenetic Regulation
Epigenetic changes alter the physical structure of the DNA without changing the genetic sequence and often regulate whether genes are turned on or off. This regulation ensures that each cell produces only proteins necessary for its function. For example, proteins that promote bone growth are not produced in muscle cells. Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
X-chromosome...
X-chromosome...
Epigenetic Regulation
Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
Epigenetic Regulation
Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
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...


