転写因子は,活性化ドメインの相分離能力によって遺伝子を活性化します
Ann Boija1, Isaac A Klein2, Benjamin R Sabari1
1Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
Cell
|November 20, 2018
まとめ
多様な転写因子 (TFs) は,その活性化ドメイン (ADs) を使用して,鍵となる共活性化因子であるメディエーターと相分離コンデンサートを形成する. OCT4,GCN4,およびエストロゲン受容体の研究で示されたように,この凝縮物形成は遺伝子活性化に不可欠である.
科学分野:
- 分子生物学
- 遺伝子規制
背景:
- 転写因子 (TF) は,DNA結合ドメイン (DBD) と活性化ドメイン (AD) を介して遺伝子発現を調節する.
- ADが遺伝子の活性化を媒介するメカニズムは,主に特徴づけられていない.
研究 の 目的:
- 媒介子共活性化剤との相互作用を調べることで,ADsの遺伝子活性化における役割を調査する.
- ADがメディエーターと相互作用するメカニズムであるかどうかを判断する.
主な方法:
- 精製したタンパク質を用いた in vitro 段階分離試験
- In vivo遺伝子活性化アッセイ
- サイト・ディレクテッド・ミュータジェネシスで,重要なアミノ酸残留を特定する.
主要な成果:
- 多様な転写因子ADは,メディエーター共活性化剤と相分離コンデンサートを形成する.
- OCT4 と GCN4 の場合,インビヴォの遺伝子活性化とインビトロのメディエーター濃縮物の形成は,同じアミノ酸残基に依存する.
- エストロゲンは,エストロゲン受容体ADとメディエーターの相分離を強化し,強化された遺伝子活性化と相関する.
結論:
- ADの相分離能力は,メディエーターとの相互作用のための保存メカニズムです.
- メディエーター-TF凝縮物の形成は,遺伝子活性化の調節に直接関与しています.
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