酵母における翻訳後のタンパク質輸送は,Secタンパク質とKar2pの浄化された複合体で再構成された酵母に含まれています
S Panzner1, L Dreier, E Hartmann
1Max-Delbrück-Center for Molecular Medicine, Berlin-Buch, Federal Republic of Germany.
Cell
|May 19, 1995
まとめ
研究者は,精製された酵母Sec複合体を使用して,翻訳後のタンパク質転位経路を再構成しました. この発見は,固有のタンパク質複合体が,エンドプラズマの網膜膜を横断して共同および翻訳後の転位を媒介することを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 蛋白質の転位によるタンパク質転位です.
背景:
- エンドプラズマ網膜 (ER) 膜を横断するタンパク質の転位は,細胞機能にとって極めて重要です.
- 主な2つの経路があります:共同翻訳と翻訳後の転位です.
研究 の 目的:
- 翻訳後のタンパク質転位経路を in vitro で再構成および分析する.
- イーストの翻訳後の転位に関与するタンパク質成分を特定する.
主な方法:
- プロテオリポソームを精製された酵母タンパク質で再構成する.
- タンパク質の転位を監視するための生化学的測定法.
主要な成果:
- 浄化された7タンパク質のSec.複合体を用いて,翻訳後のタンパク質転位を成功裏に再現した.
- 効率的な転位のために,ルメナルKar2p (BiP) とATPの要求を示した.
- 膜に結合したリボソームに関連した独特のトリメリックSec61p複合体を特定しました.
結論:
- 浄化されたSec複合体は,翻訳後のタンパク質転位を媒介する.
- 異なる膜タンパク質複合体は,異なるコ-およびポストトランスレーショントランスロケーション経路で機能する可能性が高い.
関連する概念動画
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Post-translational Translocation of Proteins to the RER
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Sec61 protein conducting channel
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Sec61 protein conducting channel
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Thylakoids are membrane-bound sac-like structures within the chloroplast that serve as sites for photosynthesis. Thylakoid lumen contains many electron transport proteins and is enclosed by a thylakoid membrane rich in the light-harvesting complex. Proteins targeted to the thylakoids are transported as precursors and are sorted by the general TOC/TIC import pathway. Once the precursor reaches the stroma, stromal processing peptidases remove their transit signal and expose thylakoid signal...


