ミトコンドリアのTCAサイクル酵素の核定位は,哺乳類のシゴティックゲノム活性化における重要なステップである
Raghavendra Nagaraj1, Mark S Sharpley1, Fangtao Chi1
1Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Cell
|January 14, 2017
まとめ
ミトコンドリアのトリカルボキシル酸 (TCA) サイクル酵素は,胚の発達初期に一時的に核に入り,エピジェネティックリモデリングとジゴティックゲノム活性化 (ZGA) に不可欠である. 核の局所化を制御し 胚の発達に影響を与えます
科学分野:
- 胚科
- エピジェネティクス
- 代謝の調節
背景:
- エピジェネティック・モディフィケーションは 転写制御と胚の発達に不可欠です
- 2細胞段階のマウス胚におけるシゴティックゲノム活性化 (ZGA) は,全体的な表遺伝的変化を伴う.
- 低ミトコンドリア活性にもかかわらず,ピルバートは2細胞後の発達に不可欠です.
研究 の 目的:
- ミトコンドリアのトリカルボキシル酸 (TCA) サイクルメタボリートと酵素が初期胚の表遺伝子改造における役割を調査する.
- ジゴティックゲノム活性化 (ZGA) のためのTCAサイクル酵素の核局所化の必要性を決定する.
主な方法:
- 初期の発達中のマウス胚におけるミトコンドリア酵素の局所化に関する分析.
- 酵素核への侵入に関連したヒストンの改変とZGAの評価
- TCAサイクル酵素の核局所化を促進するピルバートの役割の調査.
主要な成果:
- 酵素的に活性なTCAサイクル酵素は,初期のマウス胚の核に一時的に部分的に局在する.
- これらの酵素の核の局所化はピルバートに依存し,エピジェネティックリモデリングとZGAに不可欠です.
- TCAサイクル酵素の核への侵入が失敗すると,ヒストンの改変が失われ,ZGAがブロックされます.
- これらの酵素は後期的な発達段階ではミトコンドリアのみである.
- ヒトのピルバート脱水素酵素は,ヒトの胚性ゲノム活性化中に一時的な核局所化を示す.
結論:
- ミトコンドリアのTCAサイクル酵素は,早期の哺乳類の植入前の発達中に表遺伝的変化とZGAを調節する保存され,一時的な核の役割を果たします.
- 核酵素機能の重要な代謝調節体であり,胚のゲノム活性化に不可欠である.
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