広範囲にわたる否定的な応答要素は,アゴニスト・リガンドド・グルココルチコイド受容体による直接抑制を媒介する.
Milan Surjit1, Krishna Priya Ganti, Atish Mukherji
1Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS UMR7104, Inserm U964, Université de Strasbourg, Collège de France, Illkirch, 67404, France.
Cell
|April 19, 2011
まとめ
グルココルチコイド受容体 (GR) は,以前に知られているメカニズムとは独立して,新しいDNA配列 (IR nGREs) に結合することによって,遺伝子を直接抑制します. この直接的な抑制は,変動するグルココルチコイドレベルによって,新しい層の遺伝子調節を提供します.
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
- エンドクリノロジー エンドクリノロジー
背景:
- グルココルチコイド受容体 (GR) は,プラスのグルココルチコイド応答要素 (+GREs) に直接結合することにより,遺伝子転写を媒介する.
- GR媒介による抑制は,伝統的に,他のDNA関連因子との間接的な相互作用に起因していた.
- 抑制のために,負のGREs (nGREs) に直接のGR結合が報告されています.
研究 の 目的:
- 直接的なGR媒介遺伝子抑制の新しいメカニズムを調査する.
- この直接的な抑圧に関与するDNA結合配列を特定するために.
- この規制経路の有病率と生物学的関連性を決定する.
主な方法:
- GRのDNA配列への結合の分析 in vitroおよびin cellulo.
- GR.のための新しいDNA結合部位 (IR nGREs) の特定.
- グルココルチコイド治療に対する遺伝子発現分析.
- 遺伝子標的のバイオ情報分析.
主要な成果:
- グルココルチコイド受容体は,+GREsとは無関係な単純なDNA結合配列 (IR nGREs) に結合することにより,直接転写を抑制する.
- これらのIR nGREsは,agonist-liganded GR.に抑制複合体 (SMRT/NCoR) を勧誘する.
- IR nGREsを含む1000以上のオーソログマウスおよびヒトの遺伝子は, in vivoでグルココルチコイドによって抑制されます.
- このメカニズムは,異なるグルココルチコイドレベルによって遺伝子調節 (活性化および抑制) を調整することを可能にします.
結論:
- IR nGREsへの直接的なGR結合は,遺伝子抑制のための新しいメカニズムを表しています.
- この経路は,リガンドの変動に反応する,グルココルチコイドシグナル伝達における追加の調節層を提供します.
- 特定されたIR nGREsは,かなりの数の遺伝子に存在し,この規制メカニズムの広範な影響を強調しています.
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