氨基受体结合和激活的Rac uncap 氨酸丝刺刺的末端通过氨酸化物合成在透的人类血小板中
J H Hartwig1, G M Bokoch, C L Carpenter
1Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
Cell
|August 25, 1995
概括
像Rac这样的多氨基酸和GTPase在血小板中没有捕获actin丝. 这一过程对于细胞信号传递至关重要,涉及氨酸介导的氨酸丝解封.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 细胞利用actin聚合来对外部刺激作出反应.
- GTPases在指导actin聚合过程中发挥着重要作用.
- 血小板中的动因组合发生在动因丝 (F-actin) 的尖端,这些丝在静止细胞中被封闭.
研究的目的:
- 研究多酸和GTPase在血小板中的F-actin解封中的作用.
- 为了阐明调节actin组合的信号通路.
主要方法:
- 使用了透的血小板.
- 评估了对多种刺激的F-actin解封反应,包括多酸,TRAP,GTP类似物和GTP酶突变物.
- 测量了酸的合成,并使用来抑制开封.
主要成果:
- 在静止血小板中,D3和D4多酸,包括Pl4,5) P2,未封闭的F-actin.
- TRAP,GTP和GTP马S诱导了F-actin解封,而GDPβS则抑制了它.
- 构成性活跃的Rac,但不是Rho,激活的F-actin解封.
- TRAP和Rac刺激了快速的Pl{4,5) P2合成,而Pl{4,5) P2结合抑制了解封.
结论:
- 建立了一条信号通路,用于涉及Rac. Rac. 的actin组装.
- 通过酸中介的F-actin解封是这一途径的关键步骤.
- 这条通路对于细胞对TRAP等刺激的反应至关重要.
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