ATP和原始DNA的协调结合调节了原始识别复合物的ATPase活性
R D Klemm1, R J Austin, S P Bell
1Massachusetts Institute of Technology, Department of Biology, Cambridge 02139, USA.
Cell
|February 21, 1997
概括
起源识别复合体 (ORC) 使用ATP来绑定DNA复制起源. Orc1p亚单元结合和解ATP,DNA调节这些功能以控制ORC活动.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- 原始识别复合体 (ORC) 对于在真核生物中启动DNA复制至关重要.
- ORC与原始DNA的相互作用需要ATP,但ATP结合和水解的确切作用尚不清楚.
研究的目的:
- 调查特定的ORC子单位在原产地认可中对ATP结合和水解的作用.
- 阐明ATP调节ORC-DNA相互作用的机制.
主要方法:
- 生物化学试验研究ORC子单元的ATP结合和水解.
- 用DNA结合实验来评估ATP对ORC起源相互作用的影响.
- 位点导向的突变发生,以探测Orc1p ATP结合位点的功能.
主要成果:
- 有证据表明,Orc1p和Orc5p子单元可以结合ATP.
- 已经证明Orc1p可以化ATP.
- 通过原始DNA序列调节的Orc1p的ATP结合对于ORC与DNA的稳定关联至关重要.
- 由Orc1p进行的ATP水解被发现被原始DNA以特定序列的方式调节.
结论:
- ATP作为一个辅助因子,通过Orc1p ATP结合部位稳定ORC与原始DNA的结合.
- 在DNA复制启动过程中,Orc1p的ATP结合和水解活动对于调节ORC功能和功能状态之间的过渡至关重要.
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