在XRCC4-缺陷细胞中的BER和NHEJ之间的交叉声取决于hTERT过度表达
Svetlana V Sergeeva1,2, Polina S Loshchenova1,2, Dmitry Yu Oshchepkov1
1Institute of Cytology and Genetics, Russian Academy of Sciences, Lavrentieva 10, Novosibirsk 630090, Russia.
International journal of molecular sciences
|October 16, 2024
概括
击败DNA修复蛋白XRCC4减少了BER和NHEJ基因的表达. 这对正常与癌症相关细胞的细胞周期进展产生不同的影响,揭示了XRCC4的存在.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 癌症研究 癌症研究
背景情况:
- 包括基因切割修复 (BER) 和非同源末端结合 (NHEJ) 在内的DNA修复途径对于保持基因组完整性至关重要.
- DNA修复系统之间的相互作用可以影响抗癌疗法的有效性.
- 以前的研究表明,BER缺陷会降低NHEJ基因表达的调节.
研究的目的:
- 调查NHEJ缺陷,特别是XRCC4淘汰对BER通路基因表达的影响.
- 为了比较正常 (TIG-1) 和hTERT修饰 (NBE1) 细胞中对XRCC4敲击的细胞反应.
- 分析对关键DNA修复和细胞周期调节基因在mRNA和蛋白质水平的影响.
主要方法:
- 在这项研究中没有使用异种移植模型.
- 细胞系 (TIG-1和NBE1) 经历了XRCC4的淘汰.
- 使用定量PCR和西式斑点测试来评估BER的基因和蛋白质表达水平 (XRCC1,LIG3,APE1),NHEJ (LIG4,Ku70/Ku80) 和调控因素 (p53,Sp1,PARP1).
- 对细胞周期进展进行了监测.
主要成果:
- 在两个细胞系中,XRCC4敲击降低了BER和NHEJ基因的mRNA水平.
- 蛋白质水平的变化在所有研究的基因中并不均.
- 通过XRCC4的淘汰,增加了p53和Sp1蛋白质水平.
- 在正常细胞中观察到G1/S相延迟,但在hTERT修饰的细胞中没有,尽管p53.3增加.
- 在NBE1细胞中,p21水平没有显著增加,与G1/S延迟的缺乏相关.
结论:
- 基架蛋白XRCC4在DNA修复途径中起着重要的调节作用.
- XRCC4的功能可能与转录调节或mRNA代谢有关.
- 对NHEJ缺乏的不同细胞反应突显了癌症治疗中DNA修复相互作用的复杂性.
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