调控转录所需的一种托皮索马酶IIβ介导的dsDNA断裂是调节转录所需的
Bong-Gun Ju1, Victoria V Lunyak, Valentina Perissi
1Howard Hughes Medical Institute, Department of Medicine, School of Medicine, 9500 Gilman Drive, University of California, San Diego, La Jolla, CA 92093-0648, USA.
概括
信号依赖基因激活需要DNA拓聚酶IIβ来创建暂时的DNA断裂. 这一过程涉及DNA修复酶和染色质重塑以调节转录.
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.
- 基因规则 基因规则
背景情况:
- 转录启动涉及多种酶,包括DNA拓酶II (拓酶II).
- 拓酶II与基因促进体结合,可以诱导双链DNA (dsDNA) 断裂.
- 拓二酶在调节基因激活中的作用尚未完全理解.
研究的目的:
- 调查DNA拓酶II是否对信号依赖基因激活至关重要.
- 阐明将托波异粒酶II活性与转录调节联系起来的机制.
主要方法:
- 研究了由核受体和激活蛋白1介导的信号依赖基因转录.
- 研究了dSDNA断裂形成中对DNA拓酶IIβ的要求.
- 检查了多氨酸二酸盐-) 聚合酶-1 (PARP-1) 和染色体重塑因子的作用.
主要成果:
- 信号依赖的基因转录需要DNA拓酶IIβ依赖的,短暂的,局部特定的dsDNA断裂.
- 在dSDNA断裂后,可诱导多氨酸二酸盐-糖) 聚合酶-1活性.
- 这种级联促进了核细胞重塑,包括基因组H1-高流动性B组交换和染色体结构变化.
结论:
- 在受调节的基因转录过程中,DNA拓酶IIβ-依赖的dsDNA断裂是必不可少的.
- 包括PARP-1在内的DNA损伤和修复机制与基因激活有机械联系.
- 这项研究揭示了DNA断裂和修复途径在控制基因表达中的新作用.
相关概念视频
DNA Topoisomerases
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Topoisomerases are divided into two main types. Type I...
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Topoisomerases are divided into two main types. Type I...
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RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
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