信号轴PIN1-p38-CtIP保护停滞的复制分叉免受有害的降解
Francesca Vivalda1, Marco Gatti1, Letizia Manfredi1
1Institute of Molecular Cancer Research, University of Zurich, 8057 Zurich, Switzerland.
Nucleic acids research
|April 10, 2025
概括
PIN1-p38-CtIP途径稳定了停滞的复制分叉,这对基因组稳定性至关重要. 这一途径对于保护分叉是必不可少的,但对于同源重组是不可或缺的,提供了新的治疗点.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 基因组学就是基因组学.
背景情况:
- CtIP对于通过同源重组 (HR) 进行DNA双链断裂修复和保护停滞不前的复制分叉至关重要.
- 控制CtIP在分叉保护和HR中的不同角色的信号机制尚未完全理解.
研究的目的:
- 阐明调节CtIP在复制分叉稳定与同源重组中的功能的上游信号通路.
- 调查p38α激酶和PIN1在控制CTIP活动中的作用.
主要方法:
- 分析了p38α对CtIP的酸化和随后的PIN1介导的异构化.
- 使用CtIP突变来评估在叉子保护中对酸化和异构化的要求.
- 评估了PIN1或p38α抑制对抗PARP抑制剂的Brca1缺乏乳腺瘤细胞的影响.
主要成果:
- 通过p38α和PIN1异构化对CtIP的酸化对于复制叉稳定是必不可少的,但对于HR却不是.
- 缺乏功能性PIN1-p38-CtIP信号的细胞表现出停滞叉的降解.
- 一个被转锁的CtIP突变者在独立于PIN1-p38α活动的情况下挽救了分叉保护.
- 抑制PIN1或p38α恢复了对抗PARP抑制剂的Brca1缺乏的乳腺瘤细胞的化学敏感性.
结论:
- PIN1-p38-CtIP信号通路是复制分叉完整性的关键调节器.
- 这一途径代表了在某些癌症中克服对PARP抑制剂的耐药性的潜在治疗标.
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