RNAの粒子の細胞フリー形成:低複雑性の配列ドメインは,水素ゲルの内部でダイナミックな繊維を形成する
Masato Kato1, Tina W Han, Shanhai Xie
1Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, 75390-9152, USA.
Cell
|May 15, 2012
まとめ
RNA結合タンパク質の低複雑性の配列は,ダイナミックでアミロイド状の繊維の形成を促します. これらの繊維はRNA粒子の不可欠な構成要素であり,自己組織化して水素ゲルを作ることができる.
科学分野:
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
背景:
- ユカリオット細胞には,タンパク質-RNAアセンブリであるRNA粒子が特徴です.
- RNA粒子の内にあるタンパク質は,しばしばRNA結合ドメイン (例えば,KH,RRM) と,機能が不明な低複雑性 (LC) の配列を有している.
研究 の 目的:
- RNA結合タンパク質における低複雑性 (LC) 配列の機能を調査する.
- RNA粒子の形成および他の非膜結合細胞構造におけるLC配列の役割を理解する.
主な方法:
- 相互作用するタンパク質を特定するために,バイオチニル化イソクサゾール (b-isox) を使用した化学的降水.
- LC配列の自己組み立て特性に関するインビトロ研究.
- 形成されたポリマーの構造を分析するために,X線 difraktion と電子顕微鏡 (EM) を使用します.
主要な成果:
- 化学探査機 (b-isox) は,多数のRNA結合タンパク質を沈殿させ,その多くはRNA粒子の構成要素である.
- LC配列は,このb-イソックス媒介結合に必要かつ十分であると特定されました.
- LC配列は,相変化を経てヒドロゲルを形成し,それらは動的,アミロイド状の繊維にポリマー化します.
- これらの繊維は病原性アミロイドとは異なり,ダイナミックな性質を示し,異型ポリメリゼーションに対応します.
結論:
- LC配列は,RNA結合タンパク質の組み立てとRNA粒子の形成において重要な役割を果たします.
- LC配列は,ダイナミックで非膜結合の細胞構造の基本的な構成要素として機能する.
- この発見は,LC配列の機能と細胞区画の組織を理解するための新しい枠組みを提供します.
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