CRSPコアクティベーターの構造,機能,アクティベーター誘発型構造
Dylan J Taatjes1, Anders M Näär, Frank Andel
1Howard Hughes Medical Institute and, Lawrence Berkeley National Laboratory, Department of Molecular and Cell Biology, 401 Barker Hall, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|February 9, 2002
まとめ
アクティベーターによるコファクター (ARC) 複合体は,ARC-LとSp1の活性化に必要なコファクター (CRSP) の2つの部分に分離されます. CRSPは,アクティブな転写コファクターであり,アクティベーターによって影響される明確な形状を示しています.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 遺伝子規制 遺伝子規制
背景:
- 人間のコファクター複合体ARCとCRSPは,活性化剤依存転写をインビトロで媒介することが知られている.
- ARCとCRSPの構造的,機能的な関係は,共有されたサブユニットにもかかわらず,依然として不明確です.
研究 の 目的:
- ARCとCRSPのコファクター複合体間の構造的,機能的関係を調査する.
- 転写調節におけるARCサブ複合体の個々の役割を決定する.
主な方法:
- ARC複合体のアフィニティ浄化.
- ARCをARC-LおよびCRSPサブコンプレックスに生化学的に分離する.
- インビトロ転写アッセイ.
- 電子顕微鏡 (EM) と構造分析のための3D再構築.
主要な成果:
- Affinity-purified ARCは,ARC-LとCRSPという2つの異なる複合体で構成されています.
- CRSPは転写的に活性化され,ARC-Lは不活性化されます.
- EM分析は,ARC-LとCRSPの間の重要な構造的な違いを明らかにしました.
- CRSPは,アクティベータ誘発による独特な形状を示した.
結論:
- CRSPは,非活性なARC-L複合体とは異なる機能的共活性化剤である.
- CRSPにおけるアクティベーター誘発の構成の変化は,その転写的増強の鍵となる可能性が高い.
- この研究は,ARC/CRSPの転写機構内のサブユニット構成と機能的役割を明確にします.
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