アシアログリコプロテイン受容体-リガンド分離の細胞内部部位:受容体媒介性エンドサイトーシトーシス中のダブルラベル免疫電子顕微鏡
Cell
|January 1, 1983
まとめ
研究者らは,ラットの肝細胞における受容体とリガンドの解離区間 (CURL) を特定した. この臓器細胞は,受容体のリサイクルとリガンドの分解のために,アシアログリコプロテイン受容体とそのリガンドを分離します.
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.
- 肝臓病理学 肝臓病理学
背景:
- レセプター媒介性内分細胞化は,細胞がリガンドを吸収するのに極めて重要です.
- 肝臓パレンキマ細胞は,肝臓におけるエンドサイトーシスの重要な部位である.
- エンドサイト化受容体とリガンドの運命は完全に理解されていません.
研究 の 目的:
- アシアログリコプロテイン受容体とリガンド解離の細胞部位を特定する.
- エンドサイトーシス後の受容体リサイクルとリガンド分解のメカニズムを解明する.
主な方法:
- ネズミの肝臓の冷凍切開に関するダブルラベル免疫電子顕微鏡.
- 抗体とゴールドタンパク質Aを用いたアシアログリコプロテイン受容体,リガンド,クラトリンの定量測定.
- エンドサイトーシスと細胞内密輸に関与する臓器細胞の識別.
主要な成果:
- アシアログリコプロテイン受容体とリガンドは,クラスリンで覆われた膀に共内化されました.
- 新しい臓器細胞,CURL (受容体とリガンドの解離区) が特定されました.
- CURL膀は,リガンドの蓄積と受容体の濃度を管状の拡張で示し,解離を促進しました.
- CURL小胞は,リガンドの分解のために二次リソソームに成熟しているようです.
- 受容体豊富な管状構造は,受容体リサイクルのためのメカニズムを示唆しています.
結論:
- CURLは,エンドサイトーシス後のアシアログリコプロテイン受容体とリガンドの分離のための主要な部位です.
- このプロセスは,細胞表面への効率的な受容体リサイクルに不可欠です.
- リンガンドの分解は,その後のリソソーム区画で起こります.
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