在Rac中介于生长因子诱导的阿拉基酸释放
M P Peppelenbosch1, R G Qiu, A M de Vries-Smits
1Laboratory for Physiological Chemistry Utrecht University, The Netherlands.
Cell
|June 16, 1995
概括
增长因子通过Rac和Rho蛋白质触发压力纤维的形成,涉及到白血素的生产. 这项研究揭示了Rac对于表皮生长因子诱导的白血球蛋白至关重要,这些白血球蛋白对于应力纤维组装至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 增长因子信号通路调节细胞骨动态.
- 压力纤维的形成对细胞粘附和迁移至关重要.
- Rac和Rho蛋白质是actin细胞骨的关键调节者.
研究的目的:
- 阐明在生长因子诱导的应力纤维形成中Rac,Rho和白血素生成之间的关系.
- 为了确定Rac和白血在这个信号级联中的特定作用.
主要方法:
- 研究了Rac在表皮生长因子 (EGF) 诱导的酸生产中的作用.
- 分析了对EGF和一个构成性活跃的Rac突变体 (Rac V12) 的反应中的白血素生成.
- 评估了白血对于应力纤维形成的必要性和充分性以及对Rho蛋白的要求.
主要成果:
- Rac对于EGF诱导的阿拉基酸生产和随后的白血素生成至关重要.
- 构成性活跃的Rac V12可以独立于生长因子产生白血.
- 由EGF或Rac V12产生的白细胞蛋白对于应力纤维的形成是必要的和足够的.
- 取决于白内素的应力纤维的形成需要Rho蛋白.
结论:
- 确定了来自生长因子受体的信号通路,其中包括Rac,阿拉基酸生产,白血合成和Rho激活.
- 这一途径是Rac影响Rho依赖细胞骨重组的主要机制.
- 莱科特里因在Rac-和Rho-依赖的应力纤维形成中起到关键的调解作用.
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