分子チャペロンは,RXRヘテロジマーであるドロソフィラエクディゾーン受容体 (Drosophila ecdysone receptor) を活性化させます
1Department of Developmental Biology, Stanford University School of Medicine, California 94305, USA.
Cell
|April 25, 2000
まとめ
ステロイドホルモン20-hydroxyecdysoneは,受容体複合体を形成することによって,ドロソフィラの発達を活性化します. この活性化には,チャペロン複合体が必要で,Hsp90とHSC70は,エクディゾーン受容体 (EcR) を標的とする重要なインビオ成分として特定されています.
科学分野:
- 分子生物学は分子生物学である.
- 発達生物学 発達生物学について
- エンドクリノロジー エンドクリノロジー
背景:
- ステロイドホルモン20-hydroxyecdysoneは,ドロソフィラの発達を調節する.
- エクディゾン受容体 (EcR) とレチノイドX受容体ホモログ (USP) のヘテロダイマーを通じて機能する.
- RXRヘテロダイメアの活性化には,通常,チャペロン複合体を必要としません.
研究 の 目的:
- EcR/USPのDNA結合活性に対するチャペロン複合体の必要性を調査する.
- EcR/USPの活性化に不可欠なチャペロン複合体内の特定のタンパク質を特定する.
- これらのタンパク質のインビヴォの役割と,エクディゾン受容体複合体内の主な標的を決定する.
主な方法:
- シェーパーロン複合体から6つの個々のタンパク質を浄化する.
- 精製されたタンパク質がEcR/USPの活性化に十分であるかどうかを試験するためのインビトロアッセイ.
- エクディゾン受容体活性に対するHsp90とHSC70の必要性を評価するインビボ試験.
主要な成果:
- EcR/USP DNA結合活動には,付随ヘテロコンプレックスによる活性化が必要です.
- 精製された6つのチャペロンタンパク質は,EcR/USPを活性化するのに十分でした.
- 熱ショックタンパク質Hsp90とHSC70は,エクディゾンの受容体活性に不可欠である.
- エクディゾーン受容体 (EcR) は,チャペロン複合体の主要な標的である.
結論:
- 以前はRXRヘテロダイマー活性化に結びつきなかったチャペロン複合体は,ドロソフィラのEcR/USP機能に不可欠である.
- Hsp90およびHsc70を含む特定のチャペロンタンパク質は,発達中のステロイドホルモンシグナル伝達を調節する上で重要な役割を果たします.
- EcRは,シャペロン複合体によって直接調節され,ステロイド受容体活性化における保存されたメカニズムを強調しています.
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