ウヴォモルリンの1つのCa2+結合部位における単一のアミノ酸の置換により,粘着機能は廃止されます
1Max-Planck Institut für Immunobiologie, Molekulare Embryologie, Freiburg, Federal Republic of Germany.
Cell
|November 30, 1990
まとめ
合成ペプチドと突然変異のウボモルリンは,カルシウム (Ca2+) の結合が細胞粘着に不可欠であることを示しています. 単一のアスパルチン酸を交換すると,この結合が破壊され,分子の粘着機能が廃止されます.
科学分野:
- バイオケミストリー バイオケミストリー
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
背景:
- ウボモルリンは,組織の完全性にとって重要な細胞粘着分子です.
- カルシウムイオン (Ca2+) は,ウヴォモルリンの機能に不可欠であることが知られている.
- ウヴォモルリンの粘着機能における個々のCa2+結合部位の正確な役割は,まだ完全に解明されていない.
研究 の 目的:
- ウヴォモルリンの機能における特定のCa2+結合モチーフの役割を調査する.
- このモチーフ内のアミノ酸置換がCa2+結合と細胞粘着に与える影響を決定する.
主な方法:
- uvomorulin Ca2+結合部位を模倣するペプチドの合成.
- 重要なアミノ酸 (Asp から Lys または Ala) を変化させるためのウヴォモルリンのサイト誘導性変異.
- L細胞で変異したウボモルリンの発現.
- Ca2+/トリプシン消化アッセイ.
- 細胞集積測定法 細胞集積測定法 細胞集積測定法
主要な成果:
- uvomorulin Ca2+結合モチーフに対応する合成ペプチドは,Ca2+を成功的に複合する.
- ペプチドにおけるAspをLysに置き換えることで,Ca2+複合が廃止された.
- Asp to LysまたはAlaの置換による変異したウボモルリンタンパク質は,Ca2+/トリプシン消化に対する感受性の変化を示した.
- 両方の変異性ウボモルリンタンパク質は,集積測定では細胞粘着性を媒介することができなかった.
結論:
- 特定のCa2+結合部位内の単一のアスパルティック酸残留は,uvomorulinの粘着機能に不可欠です.
- このCa2+結合部位の破壊は,細胞結合の完全な喪失につながります.
- これらの発見は,特定のCa2+相互作用が細胞粘着の分子機構にとって極めて重要であることを強調しています.
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