C末端の切り取られたグルコーストランスポーターは,輸送活動のない内向きの形にロックされます
1Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Nature
|June 7, 1990
まとめ
GLUT1のグルコーストランスポーターをC端末ドメインを削除することによって変えてしまうと,GLUT1は不活性になります. これは,C端領域が,トランスポーターの構造変化と機能に決定的に重要であることを示唆しています.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- GLUT1のようなファシリテッド・グルコース・トランスポーターは,膜を横断する12のドメインを持つタンパク質ファミリーです.
- 交互変形型モデルは,促進されたグルコース輸送のメカニズムを説明します.
- GLUT1機能における細胞内C端末 (C端末) ドメインの役割は完全に理解されていません.
研究 の 目的:
- GLUT1トランスポーターの構造-機能関係を調査する.
- GLUT1媒介によるグルコース輸送における細胞内C端末ドメインの特定の役割を決定する.
主な方法:
- ウサギのGLUT1トランスポーターの削除変異体は,補完DNA (cDNA) を使用して設計されました.
- 変異体には,細胞内C端末領域の42のアミノ酸のうち37が欠けていた.
- 変異したトランスポーターは,中国ハムスター卵巣 (CHO) 細胞で発現した.
主要な成果:
- GLUT1デレーション変異体は,CHO細胞の細胞表面で成功裏に発現した.
- 改造されたGLUT1トランスポーターは,グルコース輸送活動を示せず,機能不活性化を示した.
- 機能の喪失は,交代的な形状の形成ができないことから生じるという仮説がある.
結論:
- GLUT1の細胞内C端領域は,その輸送機能に不可欠である.
- C末端ドメインの削除は,グルコース輸送に必要な形状の変化を防ぐ可能性が高い.
- GLUT1のC端末領域は,トランスポーターの内向きと外向きの形状を切り替える能力を維持する上で重要な役割を果たします.
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