阿普拉素分解了腺化RNA-DNA结点,以保持基因组完整性
Percy Tumbale1, Jessica S Williams2, Matthew J Schellenberg1
11] Laboratory of Structural Biology, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, North Carolina 27709, USA [2].
Nature
|December 24, 2013
概括
阿普拉 (APTX) 修复了在基因组维护过程中产生的有毒DNA病变. 这项研究揭示了APTX的APTX.
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:
- 细胞的基因组完整性依赖于DNA结合,但异常结合可以产生有毒的5'-腺化 (5'-AMP) DNA损伤.
- 已知aprataxin (APTX) 能够逆转DNA腺化,但其在特定修复途径中的作用尚不清楚.
研究的目的:
- 在RNase-H2依赖切除修复 (RER) 的背景下,研究APTX在修复常见的DNA损伤 - - 核酸的作用.
- 阐明APTX检测和逆转RNA-DNA结点上的腺化机制.
主要方法:
- 研究了APTX在RNase-H2-依赖的Ribonucleotides切除修复 (RER) 中的重要性.
- 对人类APTX-RNA-DNA-AMP-Zn复合体进行了结构功能研究.
主要成果:
- 已经证明DNA连接酶能产生腺化5'末端与核糖,这是RNase H2切割的特征.
- APTX能有效地修复基氨基酸RNA-DNA,在RNA-DNA损伤反应 (RDDR) 中起作用,促进细胞存活并防止S相检查点激活.
- 结构功能研究定义了APTX在RNA-DNA结点检测和逆转腺化机制,涉及A型RNA结合和构造变化.
结论:
- APTX在RNA-DNA损伤反应 (RDDR) 中发挥着至关重要的作用,通过修复腺化RNA-DNA病变,从而防止基因组不稳定性和促进细胞存活.
- 在APTX中发生的突变,与眼运动无力症1的动力衰竭相关,损害了其修复这些病变的功能.
- 腺化RNA-DNA的积累可能是导致神经系统疾病的一个因素.
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