Sec61複合体の構造は,新生ペプチド転位または膜挿入に関与しています
Marko Gogala1, Thomas Becker1, Birgitta Beatrix1
1Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Feodor-Lynen-Strasse 25, University of Munich, 81377 Munich, Germany.
Nature
|February 7, 2014
まとめ
タンパク質伝導チャネルであるSec61複合体は,膜を介してタンパク質の輸送を容易にします. 新しい冷凍-EM構造は,水性ペプチドの転位と水性恐怖ドメインの挿入の間に,その動的状態を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
- 細胞生物学 細胞生物学
背景:
- Sec61複合体 (タンパク質伝導チャネル,PCC) は,分泌およびトランスメブランタンパク質生物生成に不可欠である.
- エンドプラズマの網膜膜に位置し,同翻訳輸送のために翻訳リボソームを結合します.
- Sec61複合体はSec61α,β, γサブユニットで構成され,ペプチドの転位と膜挿入を促進します.
研究 の 目的:
- Sec61複合体の転位状態を生化学的に定義する.
- クリオ電子顕微鏡を用いて,新生ペプチド転位と膜挿入の間にSec61複合体を視覚化します.
主な方法:
- リボソームに結合したSec61複合体の冷凍電子顕微鏡 (cryo-EM) です.
- 新生ペプチドの転位または膜挿入に関与する複合体の構造分析.
主要な成果:
- 水性ペプチドの転位は,ほぼ閉じた側面ゲートと最小限の中央チャネルの再配置で起こります.
- 防水ドメインの膜挿入には,横のゲートの開きとプラグの再配置が含まれて,イオンバリアを維持します.
- Sec61複合体の異なる構造構造は,異なる転位活動と相関しています.
結論:
- タンパク質伝導チャネルとしてのSec61複合体の基本的な機能の構造モデルを提供します.
- 構造レベルでのペプチド転移と膜挿入のメカニズムを解明する.
- 多様なタンパク質輸送イベントに対応するSec61複合体のダイナミックな性質を強調しています.
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