准备含有局部特异性DNA修饰的染色体的插即用方法:染色体结构对基因切割修复的影响
Deb Ranjan Banerjee1, Charles E Deckard1, Meagan B Elinski1
1Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States.
Journal of the American Chemical Society
|June 9, 2018
概括
研究人员开发了一种用于研究DNA修复的设计染色体的新方法. 这种技术揭示了染色质结构如何影响基切除修复 (BER) 的效率,根据病变位置和染色质紧缩而显示显著的抑制或加速.
科学领域:
- 分子生物学
- 表观遗传学
- 生物化学
背景情况:
- 细胞基因组DNA被组织成染色体,影响蛋白质的DNA可访问性.
- 要了解染色体结构如何调节DNA修复,需要进行详细的体外研究.
- 之前的研究受限于无法创建具有特定位置DNA修改的核体阵列.
研究的目的:
- 开发一种用于组装化学定义的寡核酶组与特定位置修改的DNA.
- 研究染色体结构对基因切除修复 (BER) 效率的影响.
- 分析核细胞间相互作用在高阶染色体结构中调节DNA修复的作用.
主要方法:
- 开发了一种新的方法,使用切割内核酶来用含有特定修饰的合成寡核酸替换DNA片段.
- 采用精确定位的2'-脱氧化 (dU) 残留物组装的设计色素阵列.
- 在各种染色体结构中检查了 uracil DNA glycosylase (UDG) 和 apurinic/apyrimidinic endonuclease 1 (APE1) 的基切除修复 (BER) 的效率.
主要成果:
- 根据2'- 脱氧化 (dU) 损伤在紧色素中的转化位置,BER效率 (UDG/ APE1活性) 显著变化 (抑制20倍至加速5倍).
- 在单核细胞组中,UDG/ APE1 的消化速度与紧缩核细胞组相比,明显更快.
- 证明了核细胞间相互作用在高阶染色体结构中调节的关键作用.
结论:
- 开发的方法可以创建精确修改的染色质基板进行详细的体外生化研究.
- 染色体结构显著影响DNA修复效率,紧缩和核细胞间相互作用起着关键的调节作用.
- 这种平台对于研究染色体内DNA修饰的生物学意义是有价值的.
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