グルココルチコイド受容体とDNAの相互作用の結晶分析
B F Luisi1, W X Xu, Z Otwinowski
1Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06511.
Nature
|August 8, 1991
まとめ
グルココルチコイド受容体のDNA結合ドメインは,DNAを結合すると二元化します. DNAの距離は,ターゲット認識を決定的に決定し,グルココルチコイド受容体機能の特定のおよび非特定の相互作用に影響を与えます.
科学分野:
- 構造生物学 構造生物学とは
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- グルココルチコイド受容体 (GR) は,グルココルチコイドへの反応として遺伝子発現を調節するために重要な核受容体です.
- GRのDNA結合ドメイン (DBD) は,特定のDNA配列の認識と結合を担当し,転写調節を媒介する.
- GR-DNAの相互作用の構造的基礎を理解することは,様々な生理学的および病理学的プロセスにおけるその役割を解読する鍵です.
研究 の 目的:
- グルココルチコイド受容体DNA結合の基礎となる構造的メカニズムを解明する.
- DNA標的配列の変異がGR DBD二分化とDNA相互作用にどのように影響するか調査する.
- グルココルチコイド反応要素の特異性決定因子に関する洞察を提供するため.
主な方法:
- X線結晶学を用いて,GR DBDの3次元構造をDNAと複合的に決定した.
- 2つの異なるDNA構造が使用されました:一つは対称的なコンセンサス標的配列で,もう一つは中央の距離が変更されました.
- 構造分析は,二分化インターフェイス,DNA結合モード,およびサブユニット-DNA接触に焦点を当てました.
主要な成果:
- 2つの結晶構造は,2つの Zn-核化された基底構造を特徴とするGR DBDの球状の折りたたみを示した.
- DNA結合すると,GR DBDは二重化し,DNAの隣接する主要な溝にサブユニットが配置されます.
- 中央のDNAの距離を変化させると,差異結合が生じる:あるサブユニットはコンセンサス半サイトを特定的に認識し,他のサブユニットは非同類の要素と非特異的に相互作用する.
結論:
- GR DBDのDNA誘発の二分化は,標的認識における重要なステップです.
- DNA半部位間の正確な距離は,標的配列の同一性と結合特異性の重要な決定因子です.
- これらの発見は,グルココルチコイド受容体による転写調節を媒介するDNA構造とタンパク質二重化との複雑な相互作用を強調しています.
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