ストップ転送配列は,エンドプラズマ網膜膜の末端鎖のトランスロケーションのための受容体を認識します
Cell
|December 5, 1986
まとめ
ストップ転送配列は,タンパク質の転位をエンドプラズマ網膜 (ER) 膜に開始することができ,それを中断する典型的な役割とは異なり. このプロセスには,リボソームとER膜受容体が関与しています.
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
- タンパク質の密輸 タンパク質の密輸
背景:
- ストップ転送配列は,通常,エンドプラズマ網膜 (ER) 膜のタンパク質転位を停止します.
- 膜IgM重鎖のカルボキシル末端には,既知のストップ転送配列が含まれています.
研究 の 目的:
- 特定のストップトランスファーシーケンスが,ER膜を横断してタンパク質の転位を開始する可能性を調査する.
- ストップ転送シーケンス介在トランスロケーションのメカニズムと要件を特徴付ける.
主な方法:
- 特定のペプチドの文脈で膜IgM重鎖からのストップ転送配列を使用する.
- リボソームとER膜受容体によるER膜のタンパク質転位を分析する.
主要な成果:
- 停止転送配列は,特定の文脈で,ER膜の域転位を開始することができます.
- このトランスロケーションは従来の信号配列活動とは異なるが,リボソームとER受容体との依存関係を共有している.
- アミノとカルボキシ末端の側面ドメインの両方が転位することができます.
- ストップ転送シーケンス自体は,膜に転移していません.
結論:
- ストップ転送配列は二重の機能を持ち,タンパク質転位を中止したり開始したりすることができます.
- 移転配列を介した転位を停止するメカニズムには,リボソーム-ER膜転位機構との特定の相互作用が含まれます.
- これらの発見は,信号と停止転送配列とその細胞受容体との相互作用の理解を洗練します.
関連する概念動画
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01:34Protein Transport into the Inner Mitochondrial Membrane
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01:45ER Retrieval Pathway
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01:20Cotranslational Protein Translocation
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Sec61 channel partners for cotranslational translocation
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01:26Insertion of Single-pass Transmembrane Proteins in the RER
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Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
01:27Post-translational Translocation of Proteins to the RER
A sizable fraction of proteins destined for ER are first synthesized in the cell cytosol and then transported across the ER membrane–a process called post-translational translocation. Similar to cotranslationally translocated proteins, these proteins also use the Sec translocon complex to enter the ER lumen.
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...