放松调节的DNAADP-ribosylation会影响端粒复制
Anne R Wondisford1, Junyeop Lee2, Robert Lu3
1Department of Pharmacology and Chemical Biology, UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA.
Nature structural & molecular biology
|May 7, 2024
概括
DNA ADP-ribosylation (DNA-ADPr) 发生在端粒,由PARP1和TARG1调节. 这个过程的失调会影响端粒复制和完整性,影响基因组的稳定性.
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:
- ADP-ribosylation是一种翻译后修饰,在基因组稳定性,表观遗传学和免疫力方面发挥作用.
- 在保持基因组稳定性方面,DNA ADP-ribosylation (DNA-ADPr) 的特定作用和调节在很大程度上是未知的.
研究的目的:
- 为了调查DNA-ADPr是否有助于基因组稳定.
- 阐明调节端粒DNA-ADPr的机制及其对端粒功能的影响.
主要方法:
- 在使用PARP1和TARG1.1的端粒中研究了DNA-ADPr.
- 分析了DNA-ADPr与滞后链合成和单链DNA的关联.
- 使用细菌DNA的ADP-ribosyl-transferase毒素直接修改端粒DNA.
主要成果:
- 端粒被确定为DNA-ADPr的直接标,由PARP1催化并被TARG1.1删除.
- DNA-ADPr与滞后的端粒DNA合成相结合,发生在未结合的Okazaki片段和3'突起处.
- TARG1缺乏导致持续的DNA-ADPr和随后的端粒缩短,而未解的与DNA结合的ADP-ribose损害了端粒的复制和完整性.
结论:
- 端粒由PARP1和TARG1介导的DNA-ADPr进行调节.
- 适当的DNA-ADPr循环对于端粒复制和完整性至关重要,因此对于持续的基因组稳定性至关重要.
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