転写因子NF-kappaBのp50/p65ヘテロダイマーの結晶構造がDNAと結合している
F E Chen1, D B Huang, Y Q Chen
1Department of Biology, University of California, San Diego, La Jolla 92093-0359, USA.
Nature
|February 5, 1998
まとめ
DNAに結合するNF-kappaB p50/p65ヘテロダイマーの結晶構造は,各サブユニットの特定の結合部位を明らかにします. この発見は,ヘテロダイマーの強いインターフェースと変数DNA配列依存型構造を説明する.
科学分野:
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
- 遺伝学 遺伝学とは
背景:
- 核因子カッパB (NF-kappaB) の転写因子は,免疫反応と発達を含む重要な細胞過程を調節する.
- Relファミリーの重要なメンバーであるNF-kappaB p50/p65ヘテロダイマーは,kappaB DNA要素に結合し,遺伝子発現を制御する.
- 抑制カッパBタンパク質は,信号誘発メカニズムを通じてNF-カッパBの局所化と活性を調節する.
研究 の 目的:
- カッパBDNAに結合したNF-カッパBp50/p65ヘテロダイマーの結晶構造を決定する.
- ヘテロジマーのDNA結合特異性とインターフェース強さの構造的基礎を解明する.
- DNA配列が,Relファミリーのダイマー構造にどのように影響するかを理解する.
主な方法:
- 2.9Aの解像度のX線結晶学.
- 免疫グロブリン軽鎖遺伝子からのkappaBDNA強化剤とp50/p65ヘテロダイマーの共結晶化.
- 他のRelファミリーのダイマーと比較した構造分析.
主要な成果:
- 結晶構造は,異なるDNA結合サブサイトを明らかにした:p50の5'-塩基対5'-サブサイトとp65.5の4'-塩基対3'-サブサイト.
- この構造は,ホモダイマーと比較して,p50/p65ヘテロダイマーの強化された結合インターフェースを説明します.
- DNA配列に依存するRelダイマーサブユニットの構成的変動性が観察されました.
結論:
- 決定された構造は,NF-kappaB p50/p65のDNA認識と結合に関する原子レベルの洞察を提供します.
- この発見は,様々なプロモーターを持つNF-kappaBヘテロジメの差異的行動の基礎となる分子メカニズムを明らかにしています.
- この構造情報は,多様な細胞環境におけるNF-kappaB媒介の遺伝子調節を理解するために極めて重要です.
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