コカインによる可塑性におけるヒストンメチルトランスフェラーゼG9aの重要な役割
Ian Maze1, Herbert E Covington, David M Dietz
1Fishberg Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, USA.
まとめ
コカイン依存症には遺伝子発現の変化が伴う. ヒストンメチル化 (H3K9) と核アキュンベンスのG9a酵素抑制は,コカイン誘発の可塑性および中毒行動を引き起こします.
科学分野:
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- コカイン中毒は,神経の構造と行動に影響を与える遺伝子発現の変化と関連しています.
- ヒストンの改変は,遺伝子発現と神経の可塑性を調節する役割を果たします.
研究 の 目的:
- ヒストン3ライシン9 (H3K9) ディメチル化と酵素G9aがコカイン誘発の可塑性および依存性における役割を調査する.
- コカインが遺伝子発現と神経機能に影響を与える分子メカニズムを解明する.
主な方法:
- コカインによって引き起こされる遺伝子発現と神経細胞形態の変化を研究するためにマウスモデルを使用した.
- 条件付き変異生成とウイルスの媒介による遺伝子転送を用いて,核アクンベンスのG9aレベルを操作した.
- コカインを繰り返し投与した結果,測定された世界的なH3K9二メチル化レベルとG9a発現.
主要な成果:
- コカインを繰り返し投与すると,核アキュンベンスにおけるH3K9のグローバル二メチル化が低下した.
- コカインによって誘発された酵素G9aの抑制は,ヒストンの甲基化の減少を媒介した.
- コカイン誘発の転写因子DeltaFosBはG9a抑制を調節した.
- G9aのダウンレギュレーションは,マウスにおける状脊椎の可塑性とコカインの好みを高めました.
結論:
- ヒストンのメチル化,特にG9aによって調節されるH3K9の二メチル化が,コカインの長期的効果にとって極めて重要です.
- nucleus accumbensのG9a/H3K9メチル化経路は,コカイン誘発の行動的可塑性および中毒における重要な役割を果たしています.
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