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Updated: Jul 12, 2026

09:42
Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides
Published on: June 19, 2012
エンドプラズマ網膜膜のターゲティング後の信号シーケンスの認識イベント
1Max Delbrück Center for Molecular Medicine, Berlin-Buch, Federal Republic of Germany.
Cell
|July 28, 1995
まとめ
分泌タンパク質は,エンドプラズマ網膜 (ER) 膜を横断して輸送するために2つの信号認識イベントを使用します. 信号認識粒子 (SRP) とSec61p複合体は,この共翻訳プロセスに不可欠である.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- タンパク質の輸送
背景:
- エンドプラズマ網膜 (ER) 膜は,真核細胞内のタンパク質の局所化を制御する重要な障壁である.
- 分泌タンパク質は,効率的かつ正確にER膜を横断して,目的地に到達しなければなりません.
研究 の 目的:
- 哺乳類のER膜を横断する分泌タンパク質のコトランスレーション輸送の初期段階を調査する.
- タンパク質転位における信号認識粒子 (SRP) とSec61p複合体の役割を明らかにする.
主な方法:
- プレプロラクチンのコトランスレーション輸送の分析.
- サイトゾールとER膜における信号配列認識イベントの調査.
主要な成果:
- プリプロラクトインの信号配列は,シトソール内のSRPによって認識されます.
- ER膜内で第2の信号配列認識イベントが発生し,Sec61p複合体が必要になります.
- これは,リボソーム新生鎖複合体とSec61pの間の安定した相互作用につながり,転位を可能にします.
結論:
- ER膜を横断するタンパク質の転位には,少なくとも2つの異なる信号認識イベントがあります.
- Sec61p複合体は,第2の信号認識ステップと転位部位への生産的な挿入に不可欠かつ十分である.
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Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
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