Raf-1 激活了 MAP 激酶-激酶
J M Kyriakis1, H App, X F Zhang
1Diabetes Unit, Medical Services, Massachusetts General Hospital, Charlestown 02129.
Nature
|July 30, 1992
概括
这种c-raf-1原核子基因产物是一种血清蛋白/氨酸蛋白激酶,直接激活MAP激酶-激酶 (MAPK-K). 这一发现确定MAPK-K是c-Raf-1的第一个生理基质,澄清了细胞信号通路中的关键步骤.
科学领域:
- 细胞生物学 细胞生物学
- 分子瘤学分子瘤学
- 信号传输 信号传输
背景情况:
- 这种c-raf-1原基因编码了一种由细胞外刺激激活的血清蛋白/氨酸蛋白激酶.
- 一个关键的信号分子c-Raf-1的生理基质在很大程度上是未知的.
- 线原激活蛋白 (MAP) 激酶Erk1和Erk2通过MAP激酶-激酶 (MAPK-K) 的酸化来激活.
研究的目的:
- 为了确定c-Raf-1蛋白激酶的生理基质.
- 研究c-Raf-1在MAPK-K和Erk1/2.2激活中的作用.
- 为了阐明细胞信号传输中MAPK-K的上游激活器.
主要方法:
- 在v-raf转化细胞中分析构成性活跃的MAPK-K和Erk1/2.
- 使用部分净化的MAPK-K和酸酶2A.的酶分析.
- 用纯化的c-Raf-1进行体外激酶试验,以评估MAPK-K的活性.
- 阴离子交换色谱以描述MAPK-K及其与c-Raf-1的相互作用.
主要成果:
- 发现MAPK-K和Erk1/2在v-raf转化细胞中具有构成性活性.
- 酸酶2A消灭了MAPK-K,但纯化的c-Raf-1可以在体外重新激活它.
- c-Raf-1调解了50,000个M(r) 聚与MAPK-K.共同分离的选择性酸化.
- 这些发现表明c-Raf-1是MAPK-K的直接上游激活剂.
结论:
- c-Raf-1被确定为MAPK-K.K.的直接上游激活剂.
- MAPK-K是C-RAF-1原原基因产品的第一个已识别的生理基质.
- 这项研究阐明了由c-Raf-1调节的MAP激酶信号级联中的关键步骤.
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