在血清321中ATR酸化DHX9,以抑制在基因毒性应激时的R循环积累
Mei-Yin Liu1, Keng-Ru Lin1, Yuh-Ling Chien1
1Department and Graduate Institute of Pharmacology, College of Medicine, National Taiwan University, Taipei 100233, Taiwan.
Nucleic acids research
|November 6, 2023
概括
DNA/RNA杂交 (R环) 威胁着基因组的稳定性. 在S321的ATR激酶酸化DHX9基酶,在基因毒性压力期间促进R循环分离.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物化学 生物化学
背景情况:
- 异常的DNA/RNA杂交 (R-循环) 产生于转录和复制冲突,危及基因组的稳定性.
- RNA螺旋酶DHX9可以解决R循环,但其在基因毒性压力下的调节尚未完全理解.
研究的目的:
- 阐明DHX9在对基因毒性压力的反应中的调节机制.
- 研究DHX9酸化在R循环分辨率和基因组稳定性中的作用.
主要方法:
- 西方斑点检测到DHX9酸化.
- 共同免疫沉以评估蛋白质相互作用 (DHX9, γH2AX, BRCA1, RPA).
- 使用显微镜和分子分析分析R环积累.
- 局部定向突变产生非可化 (S321A) 和相仿 (S321D) 的DHX9变体.
- 对基因毒剂的细胞敏感性测定.
主要成果:
- 在DNA损伤时,DHX9被ATR激酶在S321化.
- S321酸化增强了DHX9与γH2AX,BRCA1和RPA的结合,促进了R循环的结合.
- ATR 抑制或 S321A 突变会损害 DHX9-RPA 相互作用和 R 循环分辨率,增加 R 循环积累.
- 减少RPA减少了DHX9-γH2AX的相关性.
- DHX9S321A细胞对基因毒性压力过敏,而DHX9S321D细胞表现出耐药性.
结论:
- 在S321中通过ATR介导的DHX9酸化是解决压力诱导的R循环的关键调节机制.
- 这种酸化事件对于DHX9招募RPA和随后的R循环解析至关重要,保持基因组稳定性.
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