通过柔膜片段激活EGF受体催化域的机制
Natalia Jura1, Nicholas F Endres, Kate Engel
1Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Cell
|July 1, 2009
概括
皮表皮生长因子受体 (EGFR) 信号依赖于激酶域二分化. 柔膜片段促进了这种二分化,使受体在结合器结合时激活受体.
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
- 生物化学 生物化学
背景情况:
- 表皮生长因子受体 (EGFR) 信号传递对细胞过程至关重要.
- EGFR的激活需要两个受体的激酶域之间的全相互作用.
- 众所周知,EGFR的柔膜片段可以增强激酶活性.
研究的目的:
- 阐明柔膜片段在EGFR激酶域二分化和激活中的作用.
- 了解EGFR信号的基础结构机制.
- 为了研究联体结合如何调节EGFR二分化和激活.
主要方法:
- 对EGFR激酶域和果汁膜段的结构分析.
- 生物化学试验用于研究受体二分化和激酶活性.
- 突变性研究以确定参与二分化和激活的关键残留物.
主要成果:
- EGFR的细胞内柔膜片段将酶域二元化.
- 柔膜片段的C端半端充当锁具,将激活酶域与激活器连接起来.
- 柔膜片段的N端半部分促进了二元化,可能是通过一个反平行螺旋二元体来参与跨膜螺旋体.
- 细胞外域通常会阻断二分化;带结合会释放这种阻断.
- 在非活性二元体中,C端尾阻止了激活性柔膜锁的形成,抑制了连接体独立激活.
结论:
- 柔膜片段在调解EGFR激酶域二分化和激活方面发挥着关键作用.
- 与细胞外域结合的联体释放抑制,允许柔膜介导的二分化和信号传递.
- 涉及柔膜段和C端尾部的结构机制调节EGFR活性,防止异常信号传递.
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