関連する実験動画
Updated: May 11, 2026

09:42
Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides
Published on: June 19, 2012
SecBは,E. coliのタンパク質輸出のためのサイトゾール信号認識因子として機能します
1Laboratory of Cell Biology, Howard Hughes Medical Institute, Rockefeller University, New York, New York 10021.
Cell
|August 25, 1989
まとめ
SecBタンパク質は,E. coliの膜を介して前タンパク質の転位に不可欠です. この細胞性タンパク質は,信号認識粒子 (SRP) と競合し,反転小胞 (INV) にタンパク質を輸送するために必要である.
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
- タンパク質の転位 タンパク質の転位
背景:
- 細胞膜を横断するプレタンパク質の転位は,根本的なプロセスです.
- 信号認識粒子 (SRP) は,真核生物のタンパク質ターゲティングを媒介することが知られている.
- プロカリオットにおけるタンパク質転位のメカニズムはあまり理解されていない.
研究 の 目的:
- E. coliにおけるタンパク質転位におけるSecBタンパク質の役割を調査する.
- SecBがSRPのプロカリオット同等体として機能するかどうかを判断する.
主な方法:
- SecBタンパク質の浄化.
- シグナルシーケンスの結合のための競争アッセイ.
- 細胞分化と免疫ブロット分析.
- 逆転小胞 (INV) を用いた in vitro 転位測定法.
主要な成果:
- 浄化されたSecBテトラメアは,前タンパク質の信号配列に結合する.
- SecBは,信号配列結合においてSRPと競合する.
- SecBは細胞性タンパク質である.
- SecBが枯渇した大腸菌は,転位活動を失うが,SecBの再添加によって回復する.
結論:
- SecBは,E. coliにおけるプレタンパク質転位のための重要な細胞分裂因子である.
- SecBは,SRPのプロカリオットホモログとして作用し,タンパク質を膜にターゲットにすることを容易にします.
関連する概念動画
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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.
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