拉斯的激酶抑制剂是胺激活蛋白激酶
1Laboratory of Signal Transduction, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
Cell
|April 4, 1997
概括
拉斯的激酶抑制剂 (KSR) 被确定为胺激活蛋白 (CAP) 激酶. KSR通过基米林通路调解跨膜信号,激活Raf-1并启动TNFα信号传递.
科学领域:
- 细胞信号传递途径 细胞信号传递途径
- 分子生物学分子生物学
- 信号传导传导是指信号的传导.
背景情况:
- 胺激活蛋白 (CAP) 激酶通过基米林通路中介跨膜信号传递.
- 通过酸化和激活Raf-1,CAP酶启动了促炎性瘤缩因子α (TNFα) 的作用.
研究的目的:
- 为了确定CAP激酶的分子身份.
- 调查Ras的激酶抑制剂 (KSR) 在基米林通路和TNFα信号传递中的作用.
主要方法:
- 在Caenorhabditis elegans和Drosophila中的KSR的遗传鉴定.
- 鼠标KSR的生物化学表征,包括自酸化和膜结合性质.
- 分析KSR与Raf-1的相互作用和酸化,以应对TNFα和胺类同类物.
- 在体外激酶测试中使用天然胺和其他脂质第二信使.
主要成果:
- 拉斯的激酶抑制剂 (KSR) 被确定为CAP激酶.
- 鼠标KSR作为100kDa膜结合的多,自酸化的功能.
- 过度表达KSR导致构成性Raf-1激活.
- TNFα和胺类类似物显著增强KSR自酸化,与Raf-1复合形成,以及随后的Raf-1激活.
- 具体来说,KSR在Thr269的Raf-1中酸化,这也是CAP激酶准的相同部位.
结论:
- KSR作为CAP激酶起作用,在髓线路中起着至关重要的作用.
- 通过酸化和激活Raf-1,KSR调解了TNFα诱导的信号传递.
- 这些发现阐明了跨膜信号和炎症反应的关键组成部分.
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