ラス交換因子7lesslessの息子のRas交換因子のin vivo機能分析
C A Karlovich1, L Bonfini, L McCollam
1Department of Biology and Molecular Biology Institute, University of California, Los Angeles 90024, USA.
まとめ
セブンレス (Sos) タンパク質の息子
科学分野:
- 分子生物学は分子生物学である.
- 細胞シグナリング
- 発達生物学 発達生物学とは
背景:
- Son of sevenless (Sos) タンパク質は,Rasのグアニンヌクレオチド転送因子として作用する.
- Sosは,Grb2の同類であるDrk経由でセブンレスレセプターチロシンキナーゼと相互作用する.
研究 の 目的:
- Sosタンパク質の構造-機能関係を in vivoで調査する.
- Sosの機能と局所化におけるアミノ端末とDrk結合部位の役割を決定する.
主な方法:
- ハエの体内構造機能分析.
- 特定のドメイン (アミノ末端,Drk結合部位) が欠けているSosタンパク質の断片の生成とテスト.
主要な成果:
- Sosのアミノ末端は,その機能に不可欠であり,その欠如は,支配的な負の効果をもたらします.
- Drk結合部位が欠けていたSos断片は機能し続け,Sevenless受容体に依存していた.
- Sos膜の局所化はDr.から独立していた.
結論:
- SosとSevenless受容体間のDrk独立の相互作用が提案されており,おそらくアミノ末端のプレックストリンホモロジードメインによって媒介される.
- DrkはSosの活性化剤として機能するかもしれませんが,すべてのSos機能や膜局所化に不可欠ではありません.
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