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Published on: September 3, 2016
Est1p作为端粒结合端粒酶的细胞周期调节激活剂
Andrew K P Taggart1, Shu-Chun Teng, Virginia A Zakian
1Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
Science (New York, N.Y.)
|August 10, 2002
概括
端粒酶成分Est1p和Est2p与Saccharomyces cerevisiae中的端粒有关. Est2p结合端粒的时间较早,而Est1p结合较晚,这表明了端粒酶激活的模式.
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 遗传学 是一个
背景情况:
- 端粒酶由Est2p,TLC1RNA,Est1p和Est3p组成,对于Saccharomyces cerevisiae中的端粒维护至关重要.
- 端粒酶活性受到调节,并被认为在S阶段晚期发生,取决于端粒DNA结合蛋白Cdc13p的招募.
研究的目的:
- 为了研究端粒酶成分 (Est1p,Est2p,Cdc13p) 与细胞周期中的端粒的时间关联.
- 阐明Cdc13p在端粒酶组件的招募和激活中的作用.
主要方法:
- 在细胞周期的不同阶段对Est1p,Est2p和Cdc13p的端粒关联的分析.
- 检查野生类型和cdc13-2突变酵母菌株中的端粒酶成分协会.
主要成果:
- 在S阶段晚期,Est1p,Est2p和Cdc13p都与端粒相关.
- Est2p,但不是Est1p,在S阶段晚期之前与端粒结合.
- 在cdc13-2突变体中,Est1p和Est2p的端粒结合仍然存在,这挑战了拟议的招募缺陷模型.
结论:
- 提出了一个模型,其中Est1p在S阶段晚期与端粒结合,并与Cdc13p相互作用.
- 这种相互作用可能会将非活性,与端粒结合的Est2p转化为活性端粒酶复合体.
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