95 kdの精子タンパク質はZP3と結合し,ゾナ結合反応においてチロシンキナーゼ基板として機能する
1Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, North Carolina 27710.
Cell
|June 30, 1989
まとめ
マウスの精子は95kdのタンパク質を使って,Zona pellucida (ZP) に結合し,アクロソーム反応を誘発する. このZP結合タンパク質は,チロシンキナーゼ基板としても作用し,精子と卵の相互作用シグナリングを開始します.
科学分野:
- 生殖生物学 生殖生物学
- 分子細胞生物学 分子細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- ゾナ・ペルルシダ (ZP) は,精子の結合とアクロソーム反応の開始に不可欠です.
- ZP3誘発のアクロソーム反応に関与する正確なシグナル伝達経路は不明である.
- Giのようなタンパク質は以前,精子の信号伝導に関与していた.
研究 の 目的:
- マウスの精子におけるアンチフォスフォチロジン抗体の反応性を,信号伝導の潜在的指標として調査する.
- ZP結合とアクロソーム反応に関与する精子タンパク質を特定する.
- 精子と卵の相互作用におけるチロシンリン酸化の役割を解明する.
主な方法:
- 免疫光を用いたマウスの精子におけるアンチフォスフォチロジン抗体の反応性を調べた.
- 放射性標識のZPとZP3.3が付いた精子タンパク質の塊を検知することで,ZP結合タンパク質を特定した.
- 精子の容量状態とZP相互作用と相関するフォスフォタンパク質検出.
主要な成果:
- 抗フォスフォチロジン抗体は,精子のアクロソーマ領域で52,75,および95kDのタンパク質を認識しました.
- 95 kdのタンパク質は,ZP3結合タンパク質とチロシンキナーゼ基板の両方として識別されました.
- 95 kdのタンパク質強化型チロシンキナーゼ活性に対するZP3結合は,アクロソーム反応誘導と相関しています.
結論:
- 95 kdの精子プラズマ膜タンパク質は,ZP3.3の受容体として作用する.
- この95kd受容体のZP3誘発による結合は,チロシンキナーゼの活性を刺激する.
- このシグナリングカスケードは,アクロソーマ外細胞症を誘発するメカニズムであると提案されています.
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