XPD変異は,核受容体によるTFIIH依存トランザクティベーションとRARalphaのリン酸化を防ぐ
Anne Keriel1, Anne Stary, Alain Sarasin
1Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, BP 163, 67404 Illkirch Cedex, C. U., Strasbourg, France.
Cell
|April 17, 2002
まとめ
Xeroderma pigmentosum (XP) と関連したXPD遺伝子の変異は,DNA修復を超えて核受容体の機能を損なう. この研究は,XPDを明らかにしています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- バイオケミストリー バイオケミストリー
背景:
- Xeroderma pigmentosum (XP) は,トランスクリプション/修復因子TFIIHの成分であるXPD遺伝子の変異によって引き起こされる珍しい遺伝疾患です.
- XPフェノタイプは,DNA修復を超えたXPDの役割を示唆しますが,これらは完全に理解されていません.
研究 の 目的:
- XPD遺伝子の非DNA修復機能を調査する.
- 核受容体媒介トランザクティベーションに対するXPD変異の影響を調査する.
主な方法:
- XP-D患者の細胞における核受容体トランザクティベーションの分析.
- RARalpha核受容体のリン酸化におけるXPDの役割を調査する.
- 野生型のXPDと変異したRARalpha (RARalphaS77E) の過剰発現を用いて,機能回復を評価した.
主要な成果:
- XPD変異は,RARalpha,ERalpha,ARのような核受容体のリガンド依存トランザクティベーションを低下させる.
- XPD変異は,TFIIH内のcdk7キナーゼ活性を低下させ,RARアルファリン酸化に影響する.
- 野生型のXPDまたはRARalphaS77Eでトランザクティベーションの回復が観察され,適切なRARalphaリン酸化の重要性を示している.
結論:
- TFIIHのXPDサブユニットは,リン酸化を通じて核受容体活性を調節する上で重要な役割を果たします.
- cdk7キナーゼによって媒介されるこのリン酸化は,リガンド依存遺伝子の活性化に不可欠である.
- XPDの機能はDNA修復を超えて,ホルモンの遺伝子調節に影響を与え,XP現象型に潜在的に貢献します.
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