重新定义人类XPA的DNA结合域
Norie Sugitani1, Steven M Shell, Sarah E Soss
1Departments of Biochemistry and Chemistry, and Center for Structural Biology, Vanderbilt University , Nashville, Tennessee 37232-8725, United States.
Journal of the American Chemical Society
|July 25, 2014
概括
重新定义了Xeroderma pigmentosum补充组A (XPA) 的DNA结合域 (DBD). 一个新的XPA ((98-239) 结构将DNA与全长蛋白亲和力结合在一起,帮助DNA修复研究.
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:
- Xeroderma pigmentosum补充组A (XPA) 蛋白质对于通过核酸切除修复 (NER) 进行DNA修复至关重要.
- XPA充当了支架,与NER蛋白和DNA相互作用.
- 在XPADNA结合域 (DBD) 中的突变与严重的Xeroderma pigmentosum表型有关.
研究的目的:
- 为了描述XPA DBD的DNA结合特性.
- 为了研究XPA-DNA相互作用的分子基础.
- 确定一个合适的XPA构造来研究DNA结合.
主要方法:
- 光异性质DNA结合试验. 光异性质DNA结合试验.
- 对XPA进行序列分析.
- 对C端XPA构造的生成和分析 (XPA(98-239)).
- 二维的 (15) N-(1) H 核磁共振光谱学.
主要成果:
- 之前定义的XPA DBD (XPA(98-219)) 表现出较弱的DNA结合亲和力.
- 一个重新定义的XPA构造,XPA(98-239),显示了与全长XPA相比的DNA结合亲和力.
- XPA ((98-239) 结合了 Y 形的 ssDNA-dsDNA 结合点和其他 DNA 基质.
- 核磁共振数据表明,XPA98-239) 在DNA结合时经历了形状变化.
结论:
- 应该重新定义XPA DBD,以包括C端残留物.
- XPA ((98-239) 是一个更准确的模型来研究XPA的DNA结合活性.
- 这一发现促进了对DNA修复机制和Xeroderma pigmentosum的理解.
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