在非正规部位的Pin1催化普罗林cis-trans异构的基础上存在一种连接机制
Christopher C Williams1,2, Jonathan Chuck1,2, Paola Munoz-Tello3
1Skaggs Graduate School of Chemical and Biological Sciences at Scripps Research, Jupiter, United States.
bioRxiv : the preprint server for biology
|August 2, 2024
概括
在PPARγ核受体中,prolyl异构酶Pin1酶结合并异构化普罗林键. Pin1使用连接机制来催化非正规部位的异体化,揭示了一个精细的催化模型.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 普罗林异构酶Pin1催化了普罗林键的cis-trans异构化,这是一个关键的翻译后修改.
- Pin1 具有 WW 域识别酸化胺/氨酸-氨酸 (pS/pT-P) 基因和 PPIase 域用于异构化.
- Pin1 影响各种细胞过程,包括蛋白质与蛋白质的相互作用.
研究的目的:
- 调查Pin1在人类核受体PPARγ中结合并催化普林异构化的机制.
- 阐明Pin1通过其无序的N端激活函数-1 (AF-1) 域调节PPARγ功能的作用.
- 改进Pin1.1的催化机制模型.
主要方法:
- 核磁共振 (NMR) 谱学用于识别Pin1结合点和表征相互作用.
- 位点定向的突变发生,以探讨特定动机的功能作用.
- 细胞转录试验用于评估功能后果.
- 用Pin1抑制剂治疗以评估药理效应.
主要成果:
- Pin1 结合了 PPARγ AF-1 域内的多个区域,包括由 WW 域识别的正规 pS112-P113 动机.
- Pin1还在PPARγ中结合并加速非正规的甲-氨酸 (W39-P40) 基因的 cis-trans 异体化.
- 功能性研究表明,W39-P40基因的Pin1介导异构化对PPARγ转录活性至关重要.
结论:
- Pin1采用绑定机制,利用其WW域绑定正规动机,并将PPIase域定位到远端非正规位点进行催化.
- 这种机制使Pin1能够调节像PPARγ.等内在无序蛋白质的功能.
- 这些发现为Pin1的催化机制及其在核受体调节中的作用提供了更精细的理解.
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