新種のヴィトロネクチン受容体インテグリン (アルファ・V・ベータ・X) は,癌細胞の独特の粘着性特性を有する
D A Cheresh1, J W Smith, H M Cooper
1Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037.
Cell
|April 7, 1989
まとめ
癌細胞は,ヴィトロネクチンとフィブロネクチン結合のためのユニークなインテグリン受容体を利用し,メラノーマと内皮細胞に存在するヴィトロネクチン受容体とは異なる. この新しいインテグリンは,アルファvサブユニットと新しいベータxサブユニットで構成され,細胞マトリックス相互作用における多様なインテグリン機能を強調しています.
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:
- インテグリンは,細胞-マトリックス相互作用を媒介する重要な細胞表面受容体です.
- 異なる細胞タイプには,異なるインテグリン発現プロファイルがあり,粘着に影響を与えます.
- ビトロネクチン受容体 (alpha v beta 3) は,複数のマトリックスタンパク質に結合することが知られている.
研究 の 目的:
- 癌細胞粘着に関与する新型インテグリンを特徴づける.
- 癌細胞インテグリンのサブユニット組成を決定するために.
- マトリックス認識におけるこのインテグリンの機能的役割を解明する.
主な方法:
- ビトロネクチン,フィブリノゲン,フォン・ウィレブランド因子を用いた細胞粘着測定法.
- インテグリンサブユニットを標的とした抗体阻害実験.
- 特定のインテグリンサブユニットmRNAを検出するための北極点分析.
主要な成果:
- 癌細胞は,アルファvβ3を発現するメラノーマおよび内皮細胞とは異なり,新しいインテグリンを介してビトロネクチンに結合します.
- 癌インテグリンは,アルファvサブユニットを共有しているが,別々のβxサブユニットを持っている.
- この新しいインテグリンは,ビトロネクチンとフィブロネクチンの両方の結合を媒介する.
結論:
- 癌細胞は,特定のマトリックス粘着のためにユニークなインテグリン (alpha v beta x) を使用します.
- 同型アルファサブユニットは,異なるベータサブユニットとペア化し,機能的に多様なインテグリンを作成できます.
- インテグリン構造は,細胞外マトリックス成分の差分認識を決定する.
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