鉴定酵母MCM3相关蛋白质作为Xenopus DNA复制许可因子的组成部分
Y Kubota1, S Mimura, S Nishimoto
1Department of Biology, Faculty of Science, Osaka University, Japan.
Cell
|May 19, 1995
概括
复制许可因素控制DNA复制的启动. 研究人员在Xenopus蛋提取物中发现了一种100kDa的蛋白质,这是酵母Mcm3的同类物,对DNA复制和细胞周期进展至关重要.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- DNA复制是一个基本的过程,在真核生物中受到严格监管.
- 复制许可因素对于控制DNA复制的开始至关重要.
- 了解这些因素是理解细胞循环控制和预防复制错误的关键.
研究的目的:
- 为了识别和描述Xenopus蛋提取物中的复制许可因子.
- 为了研究这个候选因子在细胞周期中的行为.
- 确定人类细胞中是否存在同类蛋白质及其与已知的酵母因子的关系.
主要方法:
- 使用Xenopus蛋提取物识别蛋白质.
- 测试DNA复制的蛋白质要求.
- 与HeLa细胞蛋白的免疫学比较.
- 对Xenopus和人类蛋白质进行cDNA的克隆和测序.
主要成果:
- 一种100kDa的蛋白质被确定为候选复制许可因子.
- 这种蛋白质与精子DNA的核前形成结合,并在复制过程中解离.
- 在HeLa细胞中发现了一种免疫学上类似的蛋白质,表现出类似的细胞周期行为.
- 鉴定到的蛋白质被发现是酵母Mcm3.的同类.
结论:
- 这种100kDa的蛋白质作为Xenopus中的复制许可因子.
- 这一因素在细胞循环依赖的DNA复制调节中起作用.
- 已识别的Xenopus和人类蛋白质是酵母Mcm3的同类,这表明跨物种的功能得到保护.
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