ステロイドホルモンの受容体キナーゼBRI1によるステロイドホルモンの認識の構造的基礎
Michael Hothorn1, Youssef Belkhadir, Marlene Dreux
1Plant Biology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA.
Nature
|June 14, 2011
まとめ
BRASSINOSTEROID INSENSITIVE 1 (BRI1) のような植物性ステロイド受容体は,ホルモン結合のためのユニークな構造を持っています. この研究は,植物成長と免疫シグナル伝達に不可欠なBRI1リガンド結合ドメイン構造を明らかにしています.
科学分野:
- 植物生物学 植物生物学
- 分子生物学と構造生物学について
- バイオケミストリー バイオケミストリー
背景:
- ポリヒドロキシル化ステロイドは,生物体のサイズと形状を調節する.
- 動物では,細胞内受容体がステロイドと結合し,植物では,BRASSINOSTEROID INSENSITIVE 1 (BRI1) のような膜結合受容体キナーゼを使用する.
研究 の 目的:
- アラビドプシス・サリアナ (Arabidopsis thaliana) のBRI1リガンド結合ドメインの構造を決定する.
- BRI1.1.によるブラッシノリドの知覚の分子基礎を理解する.
主な方法:
- 2.5 Åの解像度でX線 difraktion. 2.5 Åの解像度でX線 difraktion. 2.5 Åの解像度でX線 difraktion. 2.5 Åの解像度でX線 difraktion. 2.5 Åの解像度でX線 difraktion. 2.5 Åの解像度でX線 difraktion. 2.5 Åの解像度でX線 difraktion.
- BRI1リガンド結合ドメインの構造分析.
主要な成果:
- BRI1のリガンド結合ドメインは,25個のレウシンに富んだリピート (LRR) のスーパーヘリックスを持つ.
- ユニークな70アミノ酸の島域が,ブラッシノリド結合のためのポケットを形成します.
- 既知の変異は,ホルモン結合部位と相関しています.
結論:
- ステロイドがBRI1に結合すると,受容体活性化のための共受容体ドッキングサイトが形成される可能性が高い.
- この構造は,植物ホルモンの活性化機構,発達,免疫信号受容体の洞察を提供します.
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