拓皮索马酶1活性的表观遗传控制呈现出癌症脆弱性
Tae-Hee Lee1, Colina X Qiao1,2, Vladislav Kuzin3
1Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287.
bioRxiv : the preprint server for biology
|November 1, 2024
概括
基因组变体 macroH2A1.1 通过协调拓酶1分裂综合体 (TOP1cc) 解析来保护基因组免受DNA损伤. 它的替代拼接调节了这一过程,影响了TOP1抑制剂治疗期间的癌症脆弱性和患者存活率.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 基因组学就是基因组学.
背景情况:
- DNA交易会产生扭曲压力,危及基因组的完整性.
- 拓酶1 (TOP1) 能解决超级卷,但异常的TOP1:DNA裂变复合体 (TOP1ccs) 会导致DNA损伤.
- 保护基因组热点免受异常TOP1活动的机制尚不清楚.
研究的目的:
- 调查染色质背景在协调TOP1cc分辨率中的作用.
- 在拓应力热点上识别保护异常TOP1活动的因素.
- 探索宏H2A1替代拼接,TOP1cc修复和癌症之间的联系.
主要方法:
- 利用单细胞成像来可视化转录诱导的拓应力.
- 研究了宏H2A1异型 (宏H2A1.1和宏H2A1.2) 在聚ADP- рибо (PAR) 结合中的作用.
- 在乳腺癌细胞中进行药物基因组选,以评估对TOP1毒素的敏感性.
- 相关的宏H2A1表达与TOP1抑制剂治疗癌症患者的患者存活率数据.
主要成果:
- 基质子变体macroH2A1.1结合PAR并建立了一个TOP1允许的染色体环境.
- 宏H2A1.2异型不结合PAR,也无法对TOP1ccs进行保护.
- macroH2A1.1促进了依赖PAR的XRCC1的招募,以修复TOP1cc并防止DNA损伤.
- 损坏的宏H2A1.1拼接,常见于癌症,对TOP1毒素敏感性增加.
- 在接受TOP1抑制剂治疗的癌症患者中,低宏H2A1.1表达与改善的生存率相关.
结论:
- 染色体背景,特别是宏H2A1.1 基因组变体,对于协调TOP1cc分辨率至关重要.
- macroH2A1替代拼接作为基因组维护的表观遗传调节者,对抗TOP1相关的压力.
- macroH2A1.1在TOP1cc修复中的作用代表了潜在的癌症脆弱性和治疗点.
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