細胞外信号タンパク質は,B. subtilisにおける発達の転写因子のタンパク質分解活性化を誘発する
A E Hofmeister1, A Londoño-Vallejo, E Harry
1Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Cell
|October 20, 1995
まとめ
研究者らは,B. subtilis.で新しい細胞間信号伝導経路を発見した. この経路は,プロシグマEの成熟した転写因子シグマEへの変換をプロテオリート処理で調節する.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- 細胞シグナル伝達 細胞信号伝達
背景:
- バシルス・サブティリスは,遺伝子発現のための複雑な規制メカニズムを利用しています.
- シグマEレギュロンは,ストレス反応と細胞膜の維持を制御する.
- Pro-sigma Eは,活性化するためにタンパク質分解処理を必要とします.
研究 の 目的:
- プロシグマE活性化の生化学的メカニズムを解明する.
- 細胞間信号伝達経路の構成要素を特定するために.
- シグマE成熟におけるSpollGAとSpollRの役割について説明します.
主な方法:
- エンジニアリングされたB. subtilis菌株を用いた生化学分析.
- 条件付き成長媒体の分析. 条件付き成長媒体の分析.
- E. coli のエキスから信号因子を部分的に浄化する.
主要な成果:
- 条件付けされた媒体の要素がプロシグマE処理を誘発した.
- この因子は細胞外タンパク質SpollR.R.として特定されました.
- 膜タンパク質であるSpollGAは,タンパク質分解処理を媒介する.
- SpollRは検出され,E. coliから部分的に浄化されました.
結論:
- SpollRとSpollGAを含む細胞間信号伝導経路は,シグマEの活性化を調節する.
- SpollGAは,レセプターとプロテアゼの両方として作用する可能性が高い.
- SpollGAに結合するSpollRは,プロシグマEの細胞内処理を開始する.
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