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通过ubiquitin激活SPRTN蛋白酶的Allosteric激活维持了基因组的稳定性
Sophie Dürauer1,2, Hyun-Seo Kang3,4, Christian Wiebeler5
1Gene Center, Ludwig-Maximilians-Universität München, Munich, Germany.
Nature communications
|July 21, 2025
概括
对于基因组稳定至关重要的DNA依赖蛋白酶SPRTN,通过DNA-蛋白质交叉链接 (DPCs) 的ubiquitin修饰来激活. 这种精确的调节可以防止基因组不稳定性和相关疾病.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 通过降解DNA-蛋白质交叉链路 (DPCs),SPRTN蛋白酶对于保持基因组稳定性至关重要.
- 了解SPRTN活动的调节对于预防基因组不稳定性和像Ruijs-Aalfs综合征这样的疾病至关重要.
研究的目的:
- 调查控制SPRTN对DPC的蛋白酶活性的监管机制.
- 阐明SPRTN的杂乱蛋白酶活性是如何专门针对交联蛋白的.
主要方法:
- 在体外复制DNA-蛋白质交叉连接 (DPC) 修复,包括SUMO和ubiquitin修改.
- 蛋白质结构预测,分子动力学 (MD) 模拟和NMR光谱学.
- 在表达SPRTN变异的细胞中进行功能性测试.
主要成果:
- 发现DPC无处可见化强烈激活SPRTN,独立于其已知的无处可见素结合域.
- 乌比奎丁与SPRTN的蛋白酶域结合,诱导一个开放和活跃的 conformation.
- 突变破坏了这种全激活导致基因组不稳定性和细胞周期缺陷.
结论:
- 一种新的,依赖于全域的调节机制精确控制了 DPC 中的 SPRTN 活动.
- 这种机制确保SPRTN只在需要时和需要的地方激活,保持基因组完整性.
- 这种途径的失调与早期衰老和Ruijs-Aalfs综合征中的肝癌有关.
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