ヒトの重複膨張疾患における転写凝縮物の非混合
Shaon Basu1, Sebastian D Mackowiak1, Henri Niskanen1
1Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany.
Cell
|May 11, 2020
まとめ
転写因子 (TFs) のアミノ酸の繰り返し拡張は遺伝的障害を引き起こす. これらのTFの相分離が変化すると,細胞機能が乱され,病気のメカニズムが説明される可能性がある.
科学分野:
- 分子生物学
- 遺伝学
- 生物化学
背景:
- 転写因子 (TFs) の本質的に乱れた領域 (IDRs) のアミノ酸の繰り返し拡張は,20以上のヒト遺伝疾患に関与しています.
- これらの疾患におけるタンパク質集積の役割は議論されており,分子メカニズムに関するさらなる調査が必要である.
- 遺伝性シンポリダクティリアは,HOXD13 TFのアラニン反復拡張によって引き起こされます.
研究 の 目的:
- HOXD13におけるアラニン反復膨張が,その相分離とトランスクリプションの共活性化にどのように影響するかを調査する.
- HOXD13の重複拡張がコンデンサート組成と転写プログラムに及ぼすインビトロおよびインビボの影響を調査する.
- 類似の相分離変化が他の疾患に関連したTFの繰り返し拡大で発生するかどうかを判断する.
主な方法:
- 野生型および拡張型HOXD13の行動を評価するためのインビトロ相分離試験.
- HOXD13凝縮物組成と転写変化を分析するために,マウスモデルでの細胞研究.
- 病気に関連した他のTF (HOXA13,RUNX2,TBP) の相分離特性の比較分析
主要な成果:
- HOXD13のアラニン反復膨張は,その相分離能力と転写共同活性化剤との共凝縮能力を有意に変化させます.
- HOXD13の繰り返し膨張は,in vitroとin vivoの両方でHOXD13を含む凝縮物の組成を混乱させる.
- 他のTF (HOXA13,RUNX2,TBP) の疾患に関連した反復膨張も,その相分離特性を変化させる.
- HOXD13の繰り返し拡張により,シンポリダクティリアマウスモデルでは,転写プログラムが細胞特異的に変化します.
結論:
- 変異したTF相分離による転写コンデンサートの非混合または破壊は,繰り返し膨張に関連するヒトの病態の基礎となる可能性があります.
- これらの発見は,TFの繰り返し拡大によって引き起こされる転写不調に関連した疾患を理解するための分子枠組みを提供します.
- TFIDRの分子分類は,疾患におけるTF機能を解剖するのに役立つ.
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