通过一种抑制形来抑制受体蛋白氨酸酸酶功能的二聚化诱导的抑制
R Majeti1, A M Bilwes, J P Noel
1Department of Microbiology, University of California, San Francisco, CA 94143, USA.
概括
类似受体蛋白氨酸酸酶 (RPTPs) 的功能通过二分化来调节. 突变的EGFR-CD45仿真体揭示了一个模型,其中一个RPTPalpha酸酶域阻断了另一个的催化部位,抑制了功能.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 免疫学 免疫学 免疫学
背景情况:
- 类似受体的跨膜蛋白铁酸酶 (RPTPs) 在细胞信号传递中起着至关重要的作用.
- 规范RPTP功能和监管的精确机制仍然不完全理解.
- T细胞信号传导是RPTPs涉及的一个关键领域.
研究的目的:
- 研究RPTPs的调节,特别关注二度化作用.
- 阐明抑制T细胞信号传递中的RPTP活动的功能后果.
- 在结构和功能数据的基础上开发RPTP监管的一般模型.
主要方法:
- 构建和分析表皮生长因子受体 (EGFR) -RPTP CD45仿真体 (EGFR-CD45).
- 研究结合体诱导的二分化对T细胞信号转导中的奇默函数的影响.
- 使用RPTPalpha膜近接酸酶域的晶体结构数据.
主要成果:
- 结合体诱导的EGFR-CD45二元化抑制了其在T细胞信号转导中的功能.
- 对突变EGFR-CD45嵌合体的分析为RPTP调节提供了洞察力.
- 晶体结构显示RPTPalpha酸酶域形成了一个对称的二元体.
- 在这个二元体中,一个分子的催化部位因与另一个分子的接触而受到固态阻碍.
结论:
- 通过联体诱导的二分化,可以抑制RPTP功能.
- 对于RPTP调节的一个一般模型涉及触媒部位的二度化介导性封闭.
- RPTPalpha的结构数据支持通过二聚体形成的自我抑制机制.
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