在复制叉上从基底组素H4低乙化逆转增加了FANCA缺陷细胞中的DNA损伤
Benilde García-de Teresa1,2, Cecilia Ayala-Zambrano1,3, Mirna González-Suárez1
1Laboratorio de Citogenética, Instituto Nacional de Pediatría, Mexico City, Ciudad de México, Mexico.
PloS one
|May 31, 2024
概括
缺乏FANCA的细胞在复制分叉时表现出低乙化素H4. 使用SAHA抑制基因组脱乙酶会恢复乙化,导致这些FA/BRCA通路受损细胞的DNA损伤和细胞循环停止.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- FA/BRCA通路对于DNA复制忠实性至关重要,它可以修复跨链交叉连接,稳定复制分叉.
- 基因组翻译后修改 (PTMs),特别是基因组H4乙化,对于保持基因组完整性和复制叉稳定性至关重要.
- 在复制分叉中素乙化失调可能会损害DNA修复和基因组稳定性.
研究的目的:
- 为了研究FANCA缺少细胞中的复制分叉中的基因组H4乙化状态.
- 确定对复制分叉乙化和FANCA缺少细胞细胞的细胞平衡受素脱乙酶 (HDAC) 抑制的影响.
主要方法:
- 利用新生DNA的加速原生免疫沉 (aniPOND) 和在复制叉 (SIRF) 试验中的现场蛋白相互作用.
- 在同源FANCA缺乏和FANCA富有的细胞系中的复制分叉中比较素H4乙化.
- 评估了米托米辛C (MMC) 和HDAC抑制剂Suberoylanilide hydroxamic acid (SAHA) 对细胞表型的影响.
主要成果:
- 缺少FANCA的复制分叉显示基底酸乙化基因素H4,具有升高的基因素脱乙酶1 (HDAC1) 水平.
- 在FANCA缺乏细胞中,SAHA治疗恢复了H4乙化到对照细胞中所见的水平.
- 强制乙化诱导了DNA损伤,G2细胞周期停止,减少了RAD51焦点,并在FA细胞中增加了复制应激标志物 (-RPA-S33).
结论:
- 在复制分叉中对基因素H4的低乙化是FANCA缺乏细胞的特征.
- 通过抑制HDAC (例如,通过SAHA) 扰乱这种低乙化对FA细胞有害,破坏其补偿机制,导致DNA损伤和细胞循环停止.
- 这些发现凸显了平衡的组素乙化在FA/BRCA通路缺陷的背景下维持基因组稳定的关键作用.
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