固有のプラズマ膜タンパク質の分類は,培養されたヒト腸内皮質細胞 (Caco-2) の2箇所から行われる

K Matter¹, M Brauchbar, K Bucher

¹Department of Pharmacology, University of Basel, Switzerland.

Cell

|February 9, 1990

まとめ

この研究は,上皮細胞が血膜タンパク質をどのように分類するかを明らかにしています. タンパク質は,頂点または底辺の表面に導かれ,一部の頂点タンパク質は,最終目的地へのトランサイトシスを利用します.

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.
バイオケミストリーバイオケミストリー

背景:

極化した上皮細胞は,異なる頂上および底側膜領域を維持する.
適切なプラズマ膜タンパク質の局所化は,上皮細胞の機能にとって極めて重要です.
以前の研究では,タンパク質の分類メカニズムに関する相反するデータが示されました.

研究の目的:

分極化されたCaco-2上皮細胞における内生性プラズマ膜タンパク質の合成後の分類を調査する.
頂点および底辺のタンパク質ターゲティングに関与する経路と部位を解明する.

主な方法:

新しい合成されたタンパク質を追跡するためにパルスチェイス放射性ラベリングを使用しました.
プロテインの局所化を定量化するために,ドメイン特異の細胞表面アッセイを使用しています.
3つのアピカルタンパク質と1つのベースラテルタンパク質の密輸を分析した.

主要な成果:

アピカルタンパク質は当初,両方の膜領域に挿入された.
ベース・ラテラル領域に向けられたアピカルタンパク質の割合は様々でした.
バソラテラルからアピカル領域へのトランサイトシスは,アピカルタンパク質の異なる速度で発生しました.
ベースラテラルタンパク質は,ベースラテラル膜に限定的に局在する特定のタンパク質である.

結論:

プラズマ膜タンパク質の分類は,ゴルギ装置と基礎側膜の両方から行われます.
このデュアルサイト・ソートメカニズムは,タンパク質の密輸に関する研究で以前に観察された不一致を説明する.

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