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Analyzing and Building Nucleic Acid Structures with 3DNA
Published on: April 26, 2013
过程性加载器的晶体结构是大肠杆菌DNA聚合酶III的玛 (玛) 复合体
D Jeruzalmi1, M O'Donnell, J Kuriyan
1Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
Cell
|August 30, 2001
概括
细菌的玛复合体,一个DNA加载器,有一个显露的晶体结构,显示它的五角形布局. 这种结构表明了它如何在封闭状态和开放状态之间切换,以将β滑动加载到DNA上的机制.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 玛复合体是真核复制因子C (RFC) 的细菌同类物.
- 它作为AAA+ ATPase的功能,对DNA复制至关重要.
- 马复合体将滑动,β (同类PCNA),加载到DNA上.
研究的目的:
- 为了确定细菌玛复合体的晶体结构.
- 阐明玛复合物与β滑动相互作用的机制.
主要方法:
- 在2.7/3.0A分辨率的X射线晶体学.
主要成果:
- 晶体结构揭示了一个米式的分单元排列,其静态度为delta':gamma(3):delta.
- 由C端域形成的圆领支了N端ATP结合域的不对称排列.
- 该结构显示了不同的delta'定位器和delta关键领域.
结论:
- 该结构表明了玛复杂形状变化的机制.
- 复合体在封闭状态 (隐藏的β相互作用元素) 和开放状态 (delta无需绑定β) 之间切换.
- 这种形状交换机对于片加载功能至关重要.
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