激活EGF受体与涂层坑适配素的相互作用
1Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146.
Science (New York, N.Y.)
|July 30, 1993
概括
皮表皮生长因子 (EGF) 受体在内细胞分裂过程中在涂层坑组装之前与α-适配素结合. 这种对细胞吸收至关重要的相互作用发生在涂层坑完全形成之前.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 皮表皮生长因子 (EGF) 受体是细胞信号传递的关键媒介.
- 细胞内核是细胞内部化分子的一个基本的细胞过程.
- 适配蛋白在蛋白质贩运和膜动态中起着至关重要的作用.
研究的目的:
- 为了研究EGF受体和适应蛋白之间的相互作用在内细胞化过程中.
- 为了确定参与这种相互作用的alpha-adaptin的特定区域.
- 为了确定相对于涂层坑形成的受体-适配因子协会的时间.
主要方法:
- 使用EGF治疗的A-431细胞进行共免疫沉降测定.
- 温度变化实验 (37°C与4°C相比) 用于研究内细胞分裂.
- 阿尔法适配素的部分蛋白质分解,以映射相互作用域.
- 耗尽以抑制内分细胞分裂并研究组装前事件.
主要成果:
- 大约50%的α-适配素在37°C时与EGF受体共免疫,但在4°C时不发生.
- 部分蛋白质溶解表明,α-适配素的氨基末端域介导了与EGF受体的关联.
- 受体-适配因子协会在缺乏的细胞中增加,这表明它在完全涂层坑组装之前.
结论:
- 受体 - 适配因子协会发生在完整的细胞中,在涂层坑的完整组装之前.
- 阿尔法适配素的氨基末端域对于与EGF受体结合至关重要.
- 这种相互作用是EGF受体内细胞路径的关键早期事件.
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