P-セレクチニンのための機能的なグリコタンパク質リガンドの表現クローニング
D Sako1, X J Chang, K M Barone
1Genetics Institute, Small Molecule Drug Discovery Group, Cambridge, Massachusetts 02140.
Cell
|December 17, 1993
まとめ
研究者らは,白血球の粘着に不可欠なP-セレクチンと結合する新しいタンパク質を特定しました. このP-セレクチンリガンドは,機能するために特定の酵素を必要とし,免疫細胞の相互作用に関する新しい洞察を提供します.
科学分野:
- 分子生物学は分子生物学である.
- 免疫学 免疫学とは
- 細胞粘着性 細胞粘着性について
背景:
- P-セレクチンは,循環中の白血球と内皮細胞の間の初期粘着相互作用を媒介する.
- これらの相互作用を理解することは,免疫細胞の密輸と炎症反応の解読の鍵です.
研究 の 目的:
- P-セレクトインの機能リガンドを特定し,特徴づけること.
- P-セレクチン-リガンド結合の分子要件を解明する.
主な方法:
- HL-60のcDNAライブラリからP-セレクチンリガンドの表現クローニング.
- COS細胞をリガンドとフコシルトランスフェラーゼで変異させる.
- カルシウム依存性と抗体阻害アッセイを用いたPセレクチン結合の分析.
- リガンド発現と溶解性構造の特徴.
主要な成果:
- 機能的なP-セレクチンリガンドとして,新しいムシンのようなトランスメブランタンパク質が特定されました.
- リガンドとフコシルトランスフェラーゼの共発は,有意なP-セレクチン結合のために必要であった.
- 結合はカルシウムに依存し,抗Pセレクチン抗体によって抑制された.
- リガンドは220 kDaのホモダイマーを形成し,溶解可能な形態もP-セレクチンと結合します.
結論:
- 新しいP-セレクチンリガンドが特定され,白血球-内皮細胞結合において重要な役割を果たしている.
- フコシルトランスフェラーゼの活動は,このP-セレクチンリガンドの機能的発現に不可欠です.
- この発見は,選択媒介付着と潜在的な治療標的を理解するための分子基盤を提供します.
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