Environmental factors, such as oxidative stress, have the potential to modify the epigenetic landscape of cells. We have previously shown that DNA methyltransferase (DNMT) activity can be inhibited by sublethal doses of hydrogen peroxide (H2O2). However, site-specific changes in DNA methylation and the reversibility of any changes have not been explored. Using bead chip array technology, differential methylation was assessed in Jurkat T-lymphoma cells following exposure to H2O2. Sublethal H2O2 exposure was associated with an initial genome-wide decrease in DNA methylation in replicating cells, which was largely corrected 72 h later. However, some alterations were conserved through subsequent cycles of cell division. Significant changes to the variability of DNA methylation were also observed both globally and at the site-specific level. This research indicates that increased exposure to H2O2 can result in long-term alterations to DNA methylation patterns, providing a mechanism for environmental factors to have prolonged impact on gene expression.

中文翻译：

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过氧化氢对复制细胞中维持 DNA 甲基化的全基因组影响

环境因素，如氧化应激，有可能改变细胞的表观遗传景观。我们之前已经表明，亚致死剂量的过氧化氢 (H2O2) 可以抑制 DNA 甲基转移酶 (DNMT) 的活性。然而，尚未探索 DNA 甲基化的位点特异性变化和任何变化的可逆性。使用珠芯片阵列技术，在暴露于 H2O2 后，在 Jurkat T 淋巴瘤细胞中评估差异甲基化。亚致死的 H2O2 暴露与复制细胞中 DNA 甲基化的初始全基因组降低有关，这在 72 小时后基本得到纠正。然而，一些改变在随后的细胞分裂周期中得以保留。在全球和位点特异性水平上也观察到 DNA 甲基化变异性的显着变化。