在S. cerevisiae中进行DNA复制独立的沉默
1Division of Genetics and Development, Department of Molecular and Cell Biology, University of California, 401 Barker Hall, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|February 7, 2001
概括
为了使Saccharomyces cerevisiae中的交配类型位点沉默,不需要DNA复制. 异色染色素的形成和沉默发生在独立于复制叉的复制叉.
科学领域:
- 分子生物学分子生物学
- 酵母遗传学 酵母遗传学
- 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Saccharomyces cerevisiae中,沉默的交配位置通过异色染色体的形成被抑制.
- 异色素组装需要在早期S阶段和G(2) /M阶段之间发生细胞周期事件.
- 据说DNA复制是这种细胞周期依赖的沉默的触发因素.
研究的目的:
- 调查DNA复制通过无声交配类型位点HMRa是否对于建立异色染色素介导的沉默至关重要.
- 为了区分DNA复制与其他细胞周期事件在沉默建立中的作用.
主要方法:
- 监测染色体HMRa位置上的异色染色体的形成.
- 在非复制的异染色体HMRa磁带上监测异染色素的形成.
- 分析静音装置的建立,因为细胞通过S阶段的进展.
主要成果:
- 沉默在染色体和染色体外HMRa位点均具有相同的效率.
- 异染色素的形成和沉默发生在DNA复制叉通过HMR位点的独立.
- 沉默机构保留了细胞循环的依赖性,尽管没有复制.
结论:
- 普遍认为DNA复制是必要的,以使酵母中的交配位置沉默是不正确的.
- 细胞周期依赖的沉默建立可以发生在复制叉通过目标位点的通道没有发生.
- 其他细胞周期事件,而不是DNA复制本身,可能会调节异色素蛋白形成和沉默的时间.
相关概念视频
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02:38S-Cdk Initiates DNA Replication
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02:38S-Cdk Initiates DNA Replication
The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
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