在细胞循环进展过程中调节DNA复制起源
K Shirahige1, Y Hori, K Shiraishi
1Nara Institute of Science and Technology, Ikoma, Japan.
Nature
|October 23, 1998
概括
拉德53蛋白调节DNA复制时间,并阻断晚期起源的启动,以应对DNA损伤. 这种检查点蛋白对于监测Saccharomyces cerevisiae中的S相进展至关重要.
科学领域:
- 分子生物学分子生物学
- 细胞循环规则 细胞循环规则
- 复制DNA复制DNA复制DNA复制
背景情况:
- 在Saccharomyces cerevisiae中的第六染色体有九个DNA复制起源,具有不同的启动频率.
- 这些起源在细胞周期的S阶段连续复制.
研究的目的:
- 调查多个起源激活和S相进展调节之间的联系.
- 为了确定DNA损伤 (MMS) 和检查点基因突变 (rad53) 对起源活性和细胞周期进展的影响.
主要方法:
- 二维凝电泳测量源活动.
- 用光激活的细胞分类来监测细胞循环的进展.
- 使用甲基甲硫酸盐 (MMS) 诱导DNA损伤.
- 使用检查点基因的突变,特别是rad53.
主要成果:
- MMS治疗减缓了S阶段,并选择性地阻止了从晚期复制起源的启动.
- 一种rad53突变增强了晚期/低效的起源,并取代了MMS诱导的启动阻断.
- rad53突变导致晚期的起源更早地复制.
- orc2突变也参与抑制晚期起源.
结论:
- rad53调节了正常细胞生长过程中晚期起源启动的时间.
- rad53作为一个监控机制,阻断MMS处理的细胞的晚期起源启动.
- rad53在监测S相进展方面发挥着重要作用.
相关概念视频
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Before a cell can divide, it must accurately replicate all of its chromosomes, including the DNA and its associated histone and non-histone proteins. This process begins at numerous origins of replication during the S phase of the cell cycle in each of a cell’s chromosomes simultaneously. Certain nucleotides can act as origins of replication, but these sequences are not well defined - especially in complex, multi-cellular, eukaryotic species. The length of DNA that spans an origin of...
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01:29Replication in Eukaryotes
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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.
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.