在早期和晚期S阶段建立转录能力
Jianmin Zhang1, Feng Xu, Tamar Hashimshony
1Department of Cellular Biochemistry and Human Genetics, Hebrew University, Ein Kerem, Jerusalem, Israel.
Nature
|November 15, 2002
概括
当引入到早期S阶段核中时,外源基因表达更高. 这种DNA复制时间通过影响染色质结构来影响基因表达,从而有可能维持表观遗传状态.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 在动物细胞中,DNA复制时间被编程,基因区域在固定的S阶段时段复制.
- 家政基因早期复制,而组织特异性基因迟复制,除了它们的表达组织.
研究的目的:
- 调查S阶段的转录能力差异是否解释了可变的基因复制时间.
- 确定DNA复制时间是否影响基因表达状态的建立和维护.
主要方法:
- 在不同S相阶段向细胞注入核DNA.
- 对外基因表达水平的分析.
- 对染色质结构的评估,特别是基因素乙化.
主要成果:
- 在早期S阶段核中注射的外源基因,与注射到晚期S阶段核中的基因相比,显示出显著更高的转录活性.
- 在细胞分裂过程中,注射DNA的已确定的表达状态被维持.
- 在S阶段晚期注射的DNA被抑制,与含有脱乙基因组的染色质相关,类似于晚期复制的染色体DNA.
结论:
- 复制时间影响建立转录能力的能力,早期S阶段更宽容.
- 染色体结构,特别是基因素乙化,在S阶段晚期抑制基因表达中发挥作用.
- 在DNA复制时间和基因表达之间存在机械联系,这可能解释了表观遗传状态的维持.
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