蛋白质Eps8协调EGF受体通过Rac传递信号,并通过Rab5进行贩运
L Lanzetti1, V Rybin, M G Malabarba
1Department of Experimental Oncology, European Institute of Oncology, Milan, Italy.
Nature
|December 1, 2000
概括
蛋白质Eps8通过与Rac和Rab5GTPases相互作用,将表皮生长因子受体 (EGFR) 信号和贩运联系起来. 这种融合调节了EGFR内部化和Rac信号通路.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 信号传输 信号传输
背景情况:
- 表皮生长因子受体 (EGFR) 信号通路对于细胞生长和分化至关重要.
- 涉及受体内部化的EGFR贩运对于信号终止和调节至关重要.
- 对于EGFR信号传递和贩运之间的相互作用,特别是涉及Rho和Rab家族GTPases的相互作用,人们对此的理解尚不充分.
研究的目的:
- 阐明连接EGFR信号和贩运的分子机制.
- 为了确定整合由Rho和Rab GTPases介导的通路的蛋白质.
- 为了研究蛋白质Eps8在这个集成网络中的作用.
主要方法:
- 同免疫沉测试用于识别蛋白质复合体.
- GTPase激活蛋白 (GAP) 测试以确定酶活性.
- 西部涂抹以评估蛋白质水平和激活状态.
- 同焦显微镜可视化EGFR的贩运和定位.
主要成果:
- Eps8充当了一个支架,将EGFR信号 (通过Rac) 与贩运 (通过Rab5) 联系起来.
- Eps8与Sos1和适应蛋白E3b1相互作用,以激活Rac.
- Eps8还与RN-tre相互作用,这是一种由EGFR调节的Rab5 GTPase激活蛋白 (GAP).
- 对Eps8的RN-tre结合抑制了EGFR内部化,并减弱了Rac信号传递.
结论:
- Eps8是EGFR信号和贩运通路的关键分子整合剂.
- Eps8与E3b1/Sos1或RN-tre的相互作用决定了它在Rac激活或Rab5-介导的贩运中的功能.
- 这种Eps8的双重作用提供了一个协调调节EGFR信号和内细胞分裂的机制.
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