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一个DNA基的DarT ADP-ribosylation的分子基础
Marion Schuller1, Rachel E Butler2, Antonio Ariza1
1Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
Nature
|August 19, 2021
概括
细菌使用一种新的DNA修饰系统,ADP-ribosylation,用于生长调节和毒性. 这一过程涉及DarT-DarG毒素-抗毒素系统,它修改DNA基,影响细胞通路和细菌病原体.
科学领域:
- 生物化学
- 分子生物学
- 遗传学
背景情况:
- ADP-ribosyltransferases (ARTs) 使用NAD+修改蛋白质,调节细胞功能和细菌的致病性.
- 虽然蛋白质ADP-ribosylation已经确立,但最近的研究表明核酸是潜在的目标.
- 在各种细菌中存在的DarT-DarG毒素-抗毒素系统被研究其在ADP-ribosylation中的作用.
研究的目的:
- 通过DarT-DarG系统在细菌中研究DNA的特定,可逆ADP-ribosylation.
- 阐明DART的结构和催化机制,这是PARP家族的一个分离成员.
- 了解DNAADP-ribosylation对细菌生长和致病性的生物学影响.
主要方法:
- 在各种状态下 (无体,反应前和反应后) 高分辨率的DART结构确定.
- 生物化学试验以描述DarT和DarG的催化机制.
- 与其他ADP-ribosyltransferases,如PARP-HPF1进行比较分析.
- 使用Mycobacterium tuberculosis进行体内研究,以证明DarT- DarG在DNA复制和生长中的作用.
主要成果:
- 在细菌中通过DarT-DarG系统对乙胺基的特定,可逆ADP-ribosylation的证据.
- 结构洞察力显示DART是一种PARP家族成员,具有涉及活性位点阿尔金因的专门催化机制.
- DarG作为一种非正规的DNA修复因子,可以逆转胺结合的ADP- 核糖DNA添加物.
- 在M.结核病的染色体复制的起源上,DarT-DarG通过ADP-ribosylatingDNA调节细菌的生长.
结论:
- DarT-DarG系统代表了DNAADP-ribosylation的一个新机制,扩展了已知的ART功能.
- 这种DNA修饰在诱导毒性和作为细胞过程的信号策略方面发挥了双重作用.
- 这些发现为核酸ADP- 核糖化和PARP家族酶的演变提供了基本的见解.
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