通过二维Grb2抑制基底FGF受体信号传递
Chi-Chuan Lin1, Fernando A Melo, Ragini Ghosh
1Department of Biochemistry and Molecular Biology and Center for Biomolecular Structure and Function, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
Cell
|June 26, 2012
概括
适应蛋白Grb2积极调节纤维细胞生长因子受体2 (FGFR2) 的活性. Grb2与FGFR2的结合最初阻止了完全的受体激活,这只有在刺激和随后的Grb2酸化后才能实现.
科学领域:
- 蜂信号传输是如何进行的
- 分子生物学分子生物学
- 受体氨酸激酶的受体.
背景情况:
- 受体氨酸激酶 (RTKs) 在没有外部信号的情况下表现出基底活性.
- 这种基本活动对于下游信号是不够的,表明了监管机制.
- 纤维细胞生长因子受体2 (FGFR2) 是一个关键的RTK参与细胞过程.
研究的目的:
- 阐明控制FGFR2激活的机制.
- 研究适配蛋白Grb2在调节RTK信号传递中的作用.
- 了解基底RTK活动是如何阻止引起细胞反应的.
主要方法:
- 研究了Grb2和FGFR2.2.之间的相互作用.
- 在不同的条件下分析受体酸化状态.
- 研究了Grb2结合对FGFR2激活和下游信号传导的影响.
主要成果:
- 双基Grb2与两个FGFR2分子的C端结合,形成一个异质四聚合物.
- 这种复合物允许低水平的转酸化,但在固体上阻碍了C端酸化和信号蛋白招募.
- 刺激FGFR2导致Grb2酸化,导致Grb2解离,并使得完全的受体激活和下游信号.
结论:
- Grb2 作为 FGFR2.2 的一个关键的负调节器.
- Grb2与FGFR2的动态相互作用控制了基底和完全活跃信号状态之间的切换.
- 这种机制突出了适应蛋白在积极调节RTK信号值方面的新作用.
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