解读表观遗传UHRF1蛋白质SET和RING相关 (SRA) 域的基翻转机制
Dipanjan Mukherjee1, Stefano Ciaco1,2, Lara Martinez-Fernandez3
1Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS Université de Strasbourg, Faculté de pharmacie, 74 route du Rhin, Illkirch 67401, France.
Nucleic acids research
|September 18, 2025
概括
含有PHD和RING手指域1 (UHRF1) 的乌比奎丁类,使用基点翻转来区分5-甲基细胞因 (5mC) 和细胞因. 这一过程对于DNA甲基化复制和DNA甲基转移酶1 (DNMT1) 的招募至关重要.
科学领域:
- 表观遗传学和DNA甲基化动态
- DNA识别的分子机制
- 细胞分裂中的蛋白-DNA相互作用
背景情况:
- 含有PHD和RING指域1 (UHRF1) 的乌比奎丁类,对于维持细胞分裂期间的DNA甲基化模式至关重要.
- UHRF1的SET和RING关联 (SRA) 域识别了半甲基化CpG位点,并翻转了5-甲基细胞素 (5mC) 基.
- 这种基事件对于招募DNA甲基转移酶1 (DNMT1) 来确保DNA甲基化复制的准确性至关重要.
研究的目的:
- 为了阐明SRA诱导的基点翻转的分子机制.
- 研究UHRF1的SRA域与5-甲基细胞因子 (5mC) 与细胞因子 (C) 的差异相互作用.
- 了解SRA的基地翻转如何导致DNMT1.1的招募.
主要方法:
- 使用了光氨酸 (thG),一种光氨酸类似物,被纳入DNA复合体.
- 采用停止流量的光测量来监测基点翻转动力学.
- 结合分子动力学模拟和量子力学计算来分析蛋白质-DNA相互作用.
主要成果:
- 证明了5mC和C残留物都被SRA用可比速率常数翻转.
- 观察到反转的C残留物迅速恢复,允许SRA继续或分离.
- 表明翻转5mC会诱导SRA缓慢的形状重组,这对于DNMT1的招募至关重要.
结论:
- 由 UHRF1 的 SRA 域进行基点翻转,作为区分 5mC 和 C. 的机制.
- 随后的SRA-5mC复合体缓慢的结构重组是DNMT1招募的关键驱动因素.
- 这些发现为DNA甲基化维护的忠实性提供了关键的见解.
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