通过远程化对内在无序架构蛋白 (LAT) 的 Grb2 调节
William Y C Huang1,2, Jonathon A Ditlev1,3, Han-Kuei Chiang2
1The Howard Hughes Medical Institute Summer Institute, Marine Biological Laboratory , Woods Hole, Massachusetts 02543, United States.
Journal of the American Chemical Society
|November 29, 2017
概括
作为T细胞受体 (TCR) 信号的关键参与者,LAT蛋白的多价化显示出一种调节Grb2结合的异质机制. 这种复杂的过程阻断了信号传输,需要多个酸化事件来有效地激活T细胞.
科学领域:
- 细胞信号传输
- 分子生物学
- 免疫学
背景情况:
- 细胞内信号传导依赖于受体和支架蛋白的酸化.
- 在早期的T细胞受体 (TCR) 激活过程中,激活T细胞 (LAT) 酸化和Grb2的连接剂至关重要.
- LAT的多个化部位表明其具有复杂的调节作用.
研究的目的:
- 量化分析LAT多价化对TCR信号的影响.
- 阐明控制 LAT:Grb2 相互作用的异质机制.
- 了解膜局部化如何影响LAT:Grb2结合和信号传输.
主要方法:
- 在支持的膜上重建TCR信号通路的初始反应.
- 用组合式氨酸残留突变分析LAT结构.
- 使用Grb2作为记者和ZAP-70激酶监测LAT酸化.
主要成果:
- 发现了一种新型的化机制,其中远程酸化会影响 LAT:Grb2 的结合亲和力.
- LAT:Grb2结合是通过膜局部调节的,主要影响动力上速率.
- 通过ZAP-70在膜上的LAT酸化表现出较弱的过程性催化作用.
结论:
- LAT的多价化作为一个门,需要多个事件来有效地传输信号.
- 化改变了LAT的结构组合,调节了Grb2的可访问性.
- 这种异质调节对于控制T细胞中的信号传播至关重要.
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