LDL受容体のNPXYインターナライゼーション信号は,逆向きの回転形状を採用しています
1Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas 75235-9038.
Cell
|December 20, 1991
まとめ
内部化信号は,低密度リポタンパク質受容体のNPVY配列のように,エンドサイトーシスに不可欠な逆転構造を採用します. 欠陥のある受容体は,この重要な形状を欠いており,細胞の吸収におけるその役割を強調しています.
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.
- バイオケミストリー バイオケミストリー
背景:
- 低密度リポプロテイン受容体 (LDLR) は,コーティングピット経由で細胞内に内化するために特定の配列を使用します.
- エンドサイトーシスは,栄養素の吸収と受容体のリサイクルのための基本的な細胞プロセスです.
研究 の 目的:
- LDLRインターナライゼーションシグナル (NPVY) の構成要件を調査する.
- 特定のペプチド構成が受容体内細胞化の効率と相関するかどうかを判断する.
主な方法:
- LDLRの内部化信号とその変種を模倣するペプチドの合成.
- 生物物理技術を用いた水溶液中のペプチド構成の分析.
主要な成果:
- ネイティブのNPVY配列を持つペプチドは溶液中の逆転形状を採用する.
- エンドサイトーシスに欠陥のある変異ペプチド (Tyr置換やAsn-Ala/Pro-Ala置換など) は,この逆転をしない.
- i+3の位置にある芳香質の残留物は,逆転を誘発するのに極めて重要です.
結論:
- NPVYインターナライゼーション信号は,効率的なエンドサイトーシスに必要な重要な逆転形状を採用しています.
- この形状は,おそらくアダプター分子との結合を容易にし,受容体の内部化を媒介する.
- インターナライゼーション信号と,受容体媒介性エンドサイトーシスにおけるターンモチーフとの間には,一般的な相関関係がある.
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