在基因调节元件的氧化损伤修复机制
Swagat Ray1,2,3, Arwa A Abugable1,2, Jacob Parker1,4
1School of Biosciences, University of Sheffield, Sheffield, UK.
Nature
|September 28, 2022
概括
通过促进DNA修复和促进转录,核线性器官蛋白 NuMA 保护基因促进体免受氧化损伤. 其他国家
科学领域:
- 分子生物学
- 遗传学
- 细胞生物学
背景情况:
- 氧化基因组损伤是细胞代谢的副产品.
- 这种损伤发生在转录过程中的基因调节元件.
- 在这个过程中涉及表观遗传脱甲基.
研究的目的:
- 研究核转化器蛋白 (NuMA) 在保护促进体免受氧化损伤方面的作用.
- 阐明Numa通过何种机制来实现这种保护.
- 了解NuMA在转录和DNA修复中的作用.
主要方法:
- 评估NuMA在转录起点周围的基因组占用率.
- 分析NuMA的结合伙伴,包括RNA聚合酶II和单链断裂修复 (SSBR) 组件.
- 研究NuMA耗尽对氧化损伤和转录的影响.
- 使用新生RNA的代谢标记来识别依赖NuMA的基因.
- 用NuMA突变体进行补充测定.
主要成果:
- 在转录起点附近定位,并与RNA聚合酶II和SSBR因子结合.
- 在氧化损伤时,NuMA对染色质的丰富增加,从而促进TDP1的丰富.
- 导致促进体氧化损伤的增加.
- 通过限制RNA聚合酶II聚化,NuMA促进转录,从而增强其在暂停后的释放.
- 缺乏NuMA的细胞表现出SSBR缺陷,可以通过补充恢复.
结论:
- 在保护基因促进剂免受氧化DNA损伤方面,NuMA起着至关重要的作用.
- 在受损的染色质上促进SSBR并促进转录.
- 这种机制对于保持基因组完整性至关重要.
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