ビタミンCは,テト依存型DNA脱メチル化と,ES細胞におけるブラストシストのような状態を誘発する
Kathryn Blaschke1, Kevin T Ebata, Mohammad M Karimi
1Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Department of Obstetrics and Gynecology and Center for Reproductive Sciences, University of California San Francisco, San Francisco, California 94143, USA.
Nature
|July 2, 2013
まとめ
ビタミンCは,十一転位 (Tet) 酵素活性を直接強化し,5-ヒドロキシメチルサイトシン (5hmC) レベルを上昇させ,マウスの胚性幹細胞におけるDNA脱メチル化を促進し,その結果,表遺伝的忠誠性を維持する.
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.
- ゲノミクスゲノミクスとは
背景:
- DNAメチル化は,遺伝子発現,インプリント,レトロトランスポゾン静止を調節する重要な表遺伝子マークです.
- 十""の転位 (Tet) 酵素は,5-メチルサイトシン (5mC) を5-ヒドロキシメチルサイトシン (5hmC) に変換することによってDNA脱メチル化を媒介する.
- マウスの胚性幹細胞 (ESC) は,しばしば,テト酵素の潜在的共因子であるビタミンCなしで培養されます.
研究 の 目的:
- ネズミのESCにおけるテト酵素活性とDNAメチル化の調節におけるビタミンCの役割を調査する.
- ビタミンCがESCにおけるグローバルなDNA脱メチル化と遺伝子発現に影響を与えるかどうかを判断する.
主な方法:
- 培養マウスのESCにビタミンCを添加する.
- 5hmCと5-メチルサイトシン (5mC) レベルを測定する.
- 遺伝子プロモーターメチレーションと遺伝子発現の分析.
- 再結合剤 Tet1.1を用いた生化学的測定法
- Tet1とTet2のダブルノックアウトESCを用いた実験.
主要な成果:
- ビタミンCは,ESCにおける5hmCレベルを急速に,そして世界的に増加させた.
- その後,遺伝子プロモーターのDNA脱メチル化と生殖系遺伝子のアップレギュレーションが行われました.
- ビタミンCは,特にTet1/Tet2に依存する領域において,実験室内および体内において,Tet1の活性を増強した.
- ビタミンCの効果は,培養されたESCのメチル化増量に対して,ブラストキスタと比較してより顕著でした.
結論:
- ビタミンCは,テト酵素の活性を直接調節する作用をします.
- ビタミンCは,ESCにおけるDNAメチレーションの忠実性を維持するために不可欠です.
- ビタミンCは,発達初期に表遺伝的再プログラムに影響を与えます.
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