通过Spd1激活检查点:一个基于竞争的系统,依赖于串联无序的PCNA绑定动机
Johan G Olsen1, Andreas Prestel1, Noah Kassem1
1Structural Biology and NMR Laboratory, The Linderstrøm-Lang Centre for Protein Science and REPIN, Department of Biology, Ole Maaloes Vej 5, University of Copenhagen, 2200 Copenhagen N, Denmark.
Nucleic acids research
|January 23, 2024
概括
这项研究揭示了Spd1中的第二个PCNA结合动机,这对DNA复制检查点激活至关重要. 这一发现突显出一个平衡的竞争系统,涉及PCNA,Spd1和Suc22R2进行细胞循环调节.
科学领域:
- 分子生物学分子生物学
- 细胞循环规则 细胞循环规则
- 蛋白质与蛋白质之间的相互作用
背景情况:
- 增殖细胞核抗原 (PCNA) 对于DNA调节,复制和修复至关重要.
- 来自S. pombe的S相延缓蛋白1 (Spd1) 是一种内在无序的蛋白质,通过抑制核糖核酸减少酶来激活检查点.
- Spd1具有高度分歧的PCNA结合基因,以前没有完全表征.
研究的目的:
- 研究Spd1和PCNA之间的相互作用,重点关注Spd1的独特结合基因.
- 阐明PCNA在Spd1介导的检查点激活中的作用.
- 了解Spd1在DNA复制和细胞周期控制中的功能机制.
主要方法:
- 核磁共振 (NMR) 光谱学是指核磁共振的光谱学.
- 在酵母体内进行体内测试.
- 在X射线晶体学.
- 热量测量方法热量测量方法
- 蒙特卡洛模拟的蒙特卡洛模拟.
主要成果:
- 在Spd1中发现了一种额外的PCNA结合动机,即PIP盒,与已知的动机并列放置.
- 在Spd1上,这两个低亲和度结合点在PCNA上快速交换,使用相同的结合口袋.
- 影响任何动机的结合亲和力的突变会损害酵母体中Spd1的检查点激活功能.
结论:
- 在Spd1介导的检查点激活中,PCNA起着至关重要的作用.
- Spd1使用并排排的短线性图案,创建了一个平衡的竞争系统,涉及PCNA,Spd1和小核糖核酸还原酶子单元 (Suc22R2).
- 这种机制可能与其他被忽视的PCNA结合蛋白具有不同的动机相关.
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