由拓聚酶-I活性调节的依赖体增强剂激活
Janusz Puc1, Piotr Kozbial1, Wenbo Li1
1Howard Hughes Medical Institute, Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0648, USA.
Cell
|January 27, 2015
概括
研究人员发现,DNA拓酶I (TOP1) 的DNA切割对于激活增强剂和合成增强剂RNA (eRNA) 是必不可少的. 这个由二测试 (DHT) 和雄激素受体 (AR) 触发的过程涉及DNA修复机械的招募.
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.
- 癌症生物学 癌症生物学
背景情况:
- 增强剂是控制基因表达的调节性DNA元素.
- 增强剂作为转录单元起作用,产生增强剂RNA (eRNA).
- 相关联体依赖增强剂激活的机制仍然不完全理解.
研究的目的:
- 阐明依赖联体增强剂激活的分子机制.
- 研究DNA拓酶I (TOP1) 在eRNA合成和增强器功能中的作用.
- 利用二测试 (DHT) 诱导的前列腺癌细胞中受体 (AR) 结合来建模这种机制.
主要方法:
- 利用二测试 (DHT) 诱导雄激素受体 (AR) 结合前列腺癌细胞中的增强剂.
- 监测了DNA拓酶I (TOP1),ATR和MRN复合物的招募到AR调节增强剂.
- 评估了TOP1的DNA切割活动对eRNA合成和增强剂激活的影响.
主要成果:
- 在DHT诱导几分钟内,TOP1被迅速招募到AR调节增强剂中.
- 确定TOP1的DNA切割活动是强大的eRNA合成和增强剂激活的先决条件.
- 在TOP1招募之后,观察到ATR,MRN复合体和DNA损伤修复机械的协调招募.
结论:
- 揭示了一种新的联体依赖增强剂激活机制,涉及TOP1介导的DNA切割,以缓解 eRNA合成期间的扭曲应激.
- 突出了eRNA合成和TOP1活动在调节AR结合增强剂依赖转录中的直接联系.
- 表明这种杀策略对AR驱动癌症中的eRNA表达和转录程序有定量影响.
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