两种85kd蛋白质的特征,这些蛋白质与受体氨酸激酶,中间T/pp60c-src复合体和PI3-激酶结合
Cell
|April 5, 1991
概括
牛大脑酸氨基3-激酶 (PI3-激酶) 涉及具有SH2域的85kDa蛋白质 (p85α/β). 这些蛋白质结合氨酸激酶,但缺乏PI3-激酶活性,这表明它们在信号通路中起着调节作用.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞信号传递 细胞信号传递
背景情况:
- 酸氨基3-激酶 (PI3-激酶) 是细胞信号传输中的一个关键酶.
- 牛大脑PI3-激酶由85kDa和110kDa的子单位组成.
研究的目的:
- 为了描述牛大脑PI3-激酶的85kDa子单位 (p85α和p85β).
- 研究p85α和p85β在PI3-激酶活性和受体相互作用中的功能作用.
主要方法:
- 来自牛大脑的PI3-酶的亲和性净化.
- 氨基酸测序和PI3-激酶子单元的cDNA克隆.
- 对p85蛋白的表达和功能分析.
- 使用特定抗血清的免疫沉研究.
- 对PI3-酶复合体与受体氨酸酶结合的分析.
主要成果:
- 确定了两个相关的85kDa蛋白质,p85α和p85β,每个都含有SH3和SH2域.
- 表达的p85α和p85β与铁酸化蛋白结合,但缺乏固有的PI3-激酶活性.
- 针对p85β的抗血清免疫降低了PI3-激酶活性,表明其参与.
- 含有p85α或p85β和110kDa蛋白的活性PI3-激酶复合体与PDGF受体结合,但与EGF受体结合不一致.
结论:
- p85α和p85β是PI3-激酶的调节子单元,缺乏催化活性.
- 这些子单元调解PI3-激酶与特定的氨酸激酶的相互作用,包括PDGF受体.
- p85α和p85β在引导PI3-激酶信号传递到不同的受体氨酸激酶中起着至关重要的作用.
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