细胞内DNA的超可以发生在真核细胞中
1Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138.
Cell
|December 2, 1988
概括
酵母DNA拓酶突变体表达大肠杆菌DNA拓酶I揭示了2微米DNA的超级卷. 转录与积极和消极超卷DNA域的生成有关.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- DNA超级卷对各种DNA事务至关重要,包括复制和转录.
- DNA拓酶是通过控制超级卷曲来调节DNA拓的酶.
- 酵母中的2微米等离子体作为研究DNA拓学的模型系统.
研究的目的:
- 通过使用特定的拓酶突变体,研究酵母中DNA超级卷的机制.
- 确定转录在产生相反标志的超卷DNA域中的作用.
主要方法:
- 使用酵母DNA拓酶突变体 (top1 top2 ts菌株).
- 在酵母菌株中表达大肠杆菌DNA拓酶I.
- 分析含有诱导性促进体 (GAL1和GAL10) 的等离子体的连接数分布.
主要成果:
- 细胞内2微米DNA在表达大肠杆菌DNA多聚酶I时,在缺乏功能性酵母DNA多聚酶I和II的酵母菌株中变得积极超卷.
- 发现具有相反标志的超绕DNA域的生成与转录活动有关.
结论:
- 这项研究表明,转录与产生正和负超绕的DNA域有关.
- 大肠杆菌DNA拓聚酶I在放松负超线圈方面发挥着特定的作用,影响了酵母菌的整体DNA拓.
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