MDCK細胞におけるベースラテラルソートには,異なる細胞プラズマ領域の決定因子が必要です
W Hunziker1, C Harter, K Matter
1Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510.
Cell
|September 6, 1991
まとめ
MDCK細胞における膜タンパク質の基礎側輸送には,特定の細胞プラズマ信号が必要であり,デフォルトの分類は不要である. これらの信号は,いくつかのタンパク質の内分細胞形成の決定因子とは異なり,複雑な分類機構を示しています.
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.
- 膜タンパク質の密輸
背景:
- 膜タンパク質の基礎側輸送は,細胞の極性にとって極めて重要です.
- 現在のモデルでは,ベースラテラルソートメントがいくつかの細胞タイプでデフォルトの経路であることを示唆しています.
- 細胞プラズマ領域の決定因子は,タンパク質の局所化に影響することが知られている.
研究 の 目的:
- MDCK細胞における膜タンパク質の基礎側輸送における細胞プラズマ領域決定因子の役割を調査する.
- ベースロラテラルソートシグナルがエンドサイトーシグナルと異なるかどうかを判断する.
- 基礎側膜タンパク質の既定の分類モデルに異議を唱えるため.
主な方法:
- Madin-Darby canine kidney (MDCK) 細胞における膜タンパク質輸送を研究しています.
- タイロシン残留を含む特定のサイトプラズマ領域配列の役割を分析する.
- Fc受容体,リゾソーム性グリコタンパク質Igp120,LDL受容体などの異なる膜タンパク質の輸送経路を比較する.
主要な成果:
- MDCK細胞における基礎側輸送はデフォルトのプロセスではなく,細胞プラズマ領域の決定因子に依存する.
- いくつかのタンパク質 (Fc受容体,Igp120) の場合,決定因子はクラトリンコーティングピット内分細胞症の決定因子に似ています.
- 他のタンパク質 (LDL受容体) の場合,ベースラテラル決定因子は,エンドサイトーシス信号,特にチロシン要求と異なる.
- Igp120内のチロシンを除去すると,内部化が阻害され,アピカル表面にリダイレクトされます.
- アピカル輸送は,特定のベースラテラル決定因子が欠けている多くのタンパク質で発生し,アピカル信号が広範囲に広がることを示唆しています.
結論:
- MDCK細胞におけるベースラテラル輸送は,信号に依存した活発なプロセスである.
- ベースラテラル分類のためのサイトプラズマ領域の決定因子は多様で,エンドサイトーシス信号と普遍的に関連しているわけではありません.
- 広範囲に分布した頂上輸送信号の存在は,基礎側決定因子の欠如でタンパク質が頂上表面に到達する理由を説明します.
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