MDCK細胞におけるLDL受容体の基礎側分類: 細胞プラズマ領域には,チロシンに依存する2つの標的決定因子が含まれています
K Matter1, W Hunziker, I Mellman
1Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510.
Cell
|November 27, 1992
まとめ
研究者らは,膜タンパク質をMDCK細胞の基礎側プラズマ膜に誘導する2つの異なる信号を発見した. これらのチロシンに依存する信号は,機能的に冗長であり,細胞内イベントの共通の分類機構を示唆しています.
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 密輸
背景:
- MDCK細胞の膜タンパク質をベースラーラープラズマ膜で標的とするには,特定の細胞プラズマ領域決定因子が必要です.
- これらの決定因子はしばしばクラトリンコーティングピット局所化のための信号と関連付けられていますが,ヒトのLDL受容体で見られるように,これは必ずしもそうではありません.
研究 の 目的:
- ヒトのLDL受容体のベースラテラルターゲティングに責任を負う特定の信号を特定し,特徴づけること.
- これらのベース・ラテラル・ソート決定因子の機能的な冗長性と特徴を調査する.
主な方法:
- MDCK細胞におけるヒトLDL受容体の変異体およびキメリック受容体の発現.
- タンパク質の局所化と密輸経路の分析.
主要な成果:
- ベース・ラテラル・ターゲティングに十分な2つの独立した信号が特定されました.
- 両方の信号は,重要なチロシン残基を含んでいるが,効率は異なる.
- 1つの信号はクラトリンで覆われたピット領域とは異なるが,コリネラルである; 2つ目はC端領域にあり,エンドサイトーシスを媒介するものではない.
結論:
- 膜タンパク質は,基礎横向輸送のための機能的に冗長な信号を持つことができる.
- タイロシンを含むモチーフは,基礎側標的と内細胞症を含む複数の細胞内分類イベントの共通の特徴として機能する可能性があります.
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