Oxidative stress induces persistent telomeric DNA damage responsible for nuclear morphology change in mammalian cells.
Oxidative stress induces persistent telomeric DNA damage responsible for nuclear morphology change in mammalian cells.
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DOI：
10.1371/journal.pone.0110963
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Sgura A
中科院分区：
文献类型：
--
作者：
Coluzzi E;Colamartino M;Cozzi R;Leone S;Meneghini C;O'Callaghan N;Sgura A
端粒的主要功能之一是维持染色体和基因组的稳定性。化学和物理环境因子可显著加速端粒缩短的速率。活性氧是氧化应激的来源，可以在基因组的任何地方产生修饰的碱基（主要是8-oxoG）和单链断裂。端粒DNA序列中鸟嘌呤残基的高发生率使得端粒成为氧化损伤的优选靶点。我们的目的是在这项工作中是评估是否染色体不稳定性诱导的氧化应激是专门相关的端粒损伤。我们在体外用过氧化氢（100和200 µM）处理人原代成纤维细胞（MRC-5）1小时，并在几个时间点收集数据。为了评估氧化应激诱导的DNA损伤在处理后长达24小时的持续性，我们分别通过qPCR和改良的彗星试验分析了端粒和基因组氧化损伤。结果表明，基因组损伤完全修复，而端粒氧化损伤持续存在。端粒长度的分析揭示了治疗后48小时的显著端粒缩短，这使我们假设残留的端粒损伤可能是观察到的端粒缩短的原因。考虑到端粒长度调节对基因组稳定性的影响，我们量化了异常的核形态（核质桥、核芽和核小体），并观察到染色体不稳定性在与端粒缩短相同的时间范围内增加。在随后的时间（72和96小时），我们观察到端粒长度的恢复和染色体不稳定性的减少，让我们推测端粒缩短/功能障碍和染色体不稳定性之间的相关性。我们可以得出结论，氧化碱基损伤导致异常的核形态和端粒功能障碍是这种影响的重要贡献者。
One main function of telomeres is to maintain chromosome and genome stability. The rate of telomere shortening can be accelerated significantly by chemical and physical environmental agents. Reactive oxygen species are a source of oxidative stress and can produce modified bases (mainly 8-oxoG) and single strand breaks anywhere in the genome. The high incidence of guanine residues in telomeric DNA sequences makes the telomere a preferred target for oxidative damage. Our aim in this work is to evaluate whether chromosome instability induced by oxidative stress is related specifically to telomeric damage. We treated human primary fibroblasts (MRC-5) in vitro with hydrogen peroxide (100 and 200 µM) for 1 hr and collected data at several time points. To evaluate the persistence of oxidative stress-induced DNA damage up to 24 hrs after treatment, we analysed telomeric and genomic oxidative damage by qPCR and a modified comet assay, respectively. The results demonstrate that the genomic damage is completely repaired, while the telomeric oxidative damage persists. The analysis of telomere length reveals a significant telomere shortening 48 hrs after treatment, leading us to hypothesise that residual telomere damage could be responsible for the telomere shortening observed. Considering the influence of telomere length modulation on genomic stability, we quantified abnormal nuclear morphologies (Nucleoplasmic Bridges, Nuclear Buds and Micronuclei) and observed an increase of chromosome instability in the same time frame as telomere shortening. At subsequent times (72 and 96 hrs), we observed a restoration of telomere length and a reduction of chromosome instability, leaving us to conjecture a correlation between telomere shortening/dysfunction and chromosome instability. We can conclude that oxidative base damage leads to abnormal nuclear morphologies and that telomere dysfunction is an important contributor to this effect.
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影响因子：
3.4
作者：
Berardinelli, F.;Antoccia, A.;Sgura, A.
通讯作者：
Sgura, A.
影响因子：
7.8
作者：
Liu, L;Trimarchi, JR;Keefe, DL
通讯作者：
Keefe, DL
影响因子：
14.9
作者：
Bailey SM;Murnane JP
通讯作者：
Murnane JP
DOI：
10.1016/0921-8734(91)90018-7
发表时间：
1991-03-01
期刊：
MUTATION RESEARCH
影响因子：
--
作者：
HARLEY, CB
通讯作者：
HARLEY, CB
DOI：
10.1073/pnas.211357798
发表时间：
2001-10-23
影响因子：
11.1
作者：
Gisselsson, D;Jonson, T;Mandahl, N
通讯作者：
Mandahl, N