プロゲステロン受容体は,安定したプレイニシテーション複合体の形成を促進することによって,細胞フリー転写を刺激します
L Klein-Hitpass1, S Y Tsai, N L Weigel
1Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030.
Cell
|January 26, 1990
まとめ
鶏のプロゲステロン受容体 (cPR) は,DNA応答要素に結合することによってRNA合成を直接刺激する. ホルモンフリーCPRはまた,転写を活性化させ,開始前複合体の形成を促進することができます.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- バイオケミストリー バイオケミストリー
背景:
- プロゲステロン受容体 (PR) は,プロゲステロンに対する反応として遺伝子発現を調節する核受容体です.
- PRが転写を活性化する正確なメカニズムを理解することは,PRの生理学的役割を理解するために不可欠です.
研究 の 目的:
- RNA合成を刺激する精製鶏のプロゲステロン受容体 (cPR) の直接的な役割を調査する.
- cPR媒介による転写活性化の基礎となる分子メカニズムを解明する.
主な方法:
- プロゲステロン反応要素 (PREs) を含む精製されたcPRとDNAテンプレートを用いたin vitro転写アッセイ.
- cPRからPREへの協力的拘束研究.
- cPR DNA結合ドメイン融合タンパク質の生産と機能分析.
- cPRのホルモン独立活性化の調査.
主要な成果:
- 高度な精製されたcPRは,直接RNA合成を in vitroで刺激する.
- 転写刺激は,PREsの存在に依存し,競合するオリゴヌクレオチドによって抑制されることがあります.
- cPRが2つのPREに協力的に結合すると,シネージ的転写活性化 (27倍) が起こります.
- cPR DNA結合ドメインの融合タンパク質も転写で機能する.
- ホルモンなしのCPRは,塩処理によって活性化され,ホルモンとは無関係に転写を誘導します.
- 証拠によると,CPRは安定したプレイニシアチブ複合体の形成を促進する.
結論:
- 鶏のプロゲステロン受容体は,PREsと結合することで,直接転写を刺激する.
- PREsに結合するcPRは協力的で,トランスクリプションをシネージー的に強化します.
- cPRのホルモンによる独立した活性化は可能であり,開始前複合体の形成を促進することを含む.
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