由Hermes进行的hAT转位子末端识别的结构基础,这是来自Musca domestica的八度美洲DNA转位酶
Alison B Hickman1, Hosam E Ewis2, Xianghong Li2
1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Cell
|July 19, 2014
概括
赫尔默斯转换酶形成一个在体内转换中必不可少的八米环,与体内活性二元不同. 这种结构促进了特异性和非特异性DNA结合,用于转位子活性和目标捕获.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 结构生物学 结构生物学
背景情况:
- 赫尔梅斯是hAT转子子超级家族的成员,在许多真核生物物种中发现.
- 像麦克林托克的Ac元素这样的活性转子子是关键的移动遗传元素.
- 了解转酶结构-功能关系是移动元素研究的关键.
研究的目的:
- 阐明赫尔梅斯转移酶活动的结构基础.
- 为了研究寡合化在转换中的作用.
- 解释在hAT转子子末端的DNA识别机制.
主要方法:
- 确定赫尔梅斯转位酶-DNA复合物的晶体结构.
- 在体外生化测试以评估转化酶活性 (二次数与八次数).
- 对DNA结合域和表面的分析.
主要成果:
- 晶体结构显示,赫尔梅斯形成了一个八度环 (二度的四度环).
- 孤立的二聚体在所有转换步骤中都在体外活跃.
- 在体内转移需要八度体,具有多个特定和非特定的DNA结合点.
结论:
- 八美克组合解释了hAT转位子中的双部分DNA识别和末端不对称性.
- 八度体中的多个相互作用点增强了性,有助于转子子子末端的位置.
- 寡合化状态对于体内转移活性和调节至关重要.
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