グルココルチコイド受容体によるクロマチンの改造には,BRG1複合体が必要です
1Department of Obstetrics & Gynaecology, University of Western Ontario, London Regional Cancer Centre, Canada.
Nature
|May 20, 1998
まとめ
プロゲステロン受容体は,hBRG1/BAF複合体とのグルココルチコイド受容体相互作用を阻害することによって,クロマチンからの遺伝子活性化を抑制する. これは,受容体活性化とクロマチンの改造機能を分離することが可能であることを示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- 遺伝子規制 遺伝子規制
背景:
- 調節性DNA配列のクロマチン組成は遺伝子発現を調節する.
- クロマチンのマウス乳腺腫瘍ウイルス (MMTV) プロモーターは,受容体媒介の転写調節を研究するために使用される.
- ホルモン結合のグルココルチコイドおよびプロゲステロン受容体は,クロマチンと相互作用して遺伝子活動を制御する.
研究 の 目的:
- プロゲステロン受容体が,MMTV染色体からのグルココルチコイド受容体媒介の転写を阻害するメカニズムを調査する.
- グルココルチコイド受容体と共同活性化剤およびクロマチンの改造複合体との相互作用を特徴付ける.
- 転写活性化とクロマチンの改造活動を分離することは,ホルモン受容体相互作用タンパク質にとって実行可能かどうかを判断する.
主な方法:
- 短期間感染したMMTVDNAと,両方の受容体を発現する哺乳類の細胞における組織化されたクロマチンのテンプレートを利用した.
- プロゲステロン受容体とグルココルチコイド受容体による転写活性化の評価.
- 受容体機能におけるhBRG1/BAF染色体リモデリング複合体の役割を調査した.
主要な成果:
- プロゲステロン受容体は,一時的に感染したMMTVDNAからの転写を活性化しますが,クロマチンからの転写は活性化しません.
- プロゲステロン受容体は,グルココルチコイド受容体媒介のクロマチンの改造と転写刺激を抑制する.
- hBRG1/BAFとグルココルチコイド受容体の相互作用を防ぐことは,クロマチンテンプレートトランスクリプションをブロックしますが,一時的なDNAトランスクリプションはしません.
結論:
- プロゲステロン受容体のMMTV染色体転写の抑制は,hBRG1/BAF複合体とのグルココルチコイド受容体の相互作用への干渉を含む.
- この発見は,ホルモン受容体相互作用タンパク質の染色体改造活動から転写活性化を分離する潜在的なメカニズムを示唆しています.
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