SFPQ将组素H3.3沉积引导到DNA重复中的R环,以保护基因组稳定性
Alessandro Ferrando1,2, Michele Giaquinto1, Luisa M R Napolitano3
1Dipartimento di Scienze della Vita, Università degli Studi di Trieste, Trieste, Italy.
Nature communications
|February 24, 2026
概括
通过管理R-循环,RNA结合蛋白SFPQ可以防止重复性基因组区域的DNA损伤. 它的损失导致基因组不稳定,并激活免疫信号,与较好的肉瘤患者生存相关.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 基因组学就是基因组学.
背景情况:
- R环是核酸结构,涉及到基因组的不稳定性.
- 重复的DNA元素容易形成R循环.
- 非计划的R循环与DNA复制和转录发生冲突.
研究的目的:
- 研究RNA结合蛋白SFPQ在抑制R循环介导的复制应激中的作用.
- 了解SFPQ在维持重复元素的基因组稳定性的机制.
主要方法:
- 在体外R循环结合测试.
- 染色素关联研究.
- 分析基因素修饰和DNA损伤标记物的分析.
- 对先天免疫信号激活的评估.
- 与患者生存数据的相关性.
主要成果:
- 在重复的元素 (端粒,中粒,LINE-1,SINE) 中,SFPQ抑制了R循环形成和复制应激.
- SFPQ结合R循环,与R循环染色体结合,并招募DAXX进行适当的核细胞模板.
- SFPQ的损失导致DAXX的移位,减少了基因组H3.3,基因组不稳定性和细胞质DNA.
- 细胞质DNA激活了cGAS/STING天生的免疫通路.
结论:
- 在重复性DNA中,SFPQ是R环相关基因组不稳定的关键抑制剂.
- 通过SFPQ介导的DAXX招募对于保持基因组完整性和防止异常免疫激活至关重要.
- 失去SFPQ和随后的免疫激活与沙尔科马患者的生存率改善相关.
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