APPL蛋白质将Rab5与通过内体隔间的核信号传导联系起来
Marta Miaczynska1, Savvas Christoforidis, Angelika Giner
1Max Planck Institute for Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany.
Cell
|March 16, 2004
概括
这项研究发现了一种新的信号通路,将内分体与核连接起来. Rab5效应器APPL1和APPL2将细胞外信号与基因表达和细胞增殖联系起来.
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:
- 细胞外信号通过细胞质级流传到细胞核.
- 小型GTPase Rab5调节细胞内核分裂,对细胞过程至关重要.
- 内体内体区在信号传导中发挥作用.
研究的目的:
- 确定直接连接Rab5到信号转导和线粒发生的途径.
- 阐明 Rab5 效应器 APPL1 和 APPL2 在该途径中的作用.
- 了解内体信号如何影响核事件和基因表达.
主要方法:
- 使用了Rab5,APPL1和APPL2蛋白质.
- 在细胞外刺激 (EGF,氧化应激) 上研究了蛋白质转位.
- 研究了与NuRD/MeCP1复合体的相互作用以及对细胞增殖的影响.
主要成果:
- 确定了一条涉及Rab5,APPL1和APPL2.2的途径.
- 在刺激时,APPL1转移到核中,与NuRD/MeCP1.1相互作用.
- APPL1和APPL2对于细胞增殖至关重要,依赖于Rab5结合.
结论:
- 一个含有Rab5和APPL蛋白质的内体作为信号中间体.
- 这一途径直接将血信号与核事件和基因调节联系起来.
- Rab5-APPL信号传递对于细胞增殖和对刺激的反应至关重要.
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