PGC7はヒストンH3K9me2と結合し,初期胚における5mCから5hmCへの変換から保護する
Toshinobu Nakamura1, Yu-Jung Liu, Hiroyuki Nakashima
1Department of Pathology, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan. tnakamura@nagahama-i-bio.ac.jp
Nature
|June 23, 2012
まとめ
PGC7タンパク質は,DNAを5-hydroxymethylcytosine (5hmC) に変換することを防ぐことでDNAメチレーションを維持する. この表遺伝的調節には,初期の発達と潜在的に体細胞にとって重要な特定のヒストンマークへの結合が含まれます.
科学分野:
- エピジェネティクス エピジェネティクス
- 発達生物学 発達生物学について
- ゲノミクスゲノミクスとは
背景:
- 5-メチルサイトシン (5mC) は,細胞の分化過程における表遺伝子遺伝子調節に不可欠である.
- 5メチルシトシンは,Tet酵素によって5ヒドロキシメチルシトシン (5hmC) に変換することができる.
- 5mCと5hmCのバランスは,多能性と系統のコミットメントに関連しています.
研究 の 目的:
- PGC7がDNAメチレーションを維持するメカニズムを解明する.
- PGC7,Tet3,ヒストンの改変の相互作用を調査する.
- 母性およびインプリントDNAメチレーションを保護するPGC7の役割を理解するために.
主な方法:
- 染色体免疫プレシピテーション (ChIP) アッセイは,PGC7結合を検出する.
- DNAメチル化およびヒドロキシメチル化パターンの分析.
- PGC7の機能を in vivoで評価するためにマウスモデルでの研究.
主要な成果:
- PGC7は,H3K9me2.2.でマークされた母性染色体と結合する.
- PGC7は,5mCから5hmCへのテト3媒介による変換を阻害する.
- PGC7は,初期の胚形成において,H3K9me2でマークされたインプリントロシを保護する.
結論:
- PGC7は,H3K9me2染色体.H3K9me2と結合することで,Tet3媒介による変換から5mCを保護する.
- このメカニズムは,胚形成の初期にDNAメチレーションを維持するために不可欠です.
- 同様の調節メカニズムは,体細胞にも作用する可能性がある.
関連する概念動画
Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
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...
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...
Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
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...
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...
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...
Position-effect Variegation
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
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,...


