Relationship between DNA damage response, initiated by camptothecin or oxidative stress, and DNA replication, analyzed by quantitative 3D image analysis.
Relationship between DNA damage response, initiated by camptothecin or oxidative stress, and DNA replication, analyzed by quantitative 3D image analysis.
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DOI：
10.1002/cyto.a.22327
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发表时间：
2013-10
期刊：
影响因子：
3.7
通讯作者：
Dobrucki, J. W.
中科院分区：
文献类型：
--
作者：
Berniak, K.;Rybak, P.;Bernas, T.;Zarebski, M.;Biela, E.;Zhao, H.;Darzynkiewicz, Z.;Dobrucki, J. W.
关键词：
描述了一种对共聚焦显微镜检测到的离散核事件之间的空间 (3D) 关系进行定量分析的方法，并将其应用于分析经喜树碱 (Cpt) 或过氧化氢 (H2O2) 处理的细胞中 DNA 损伤信号位点 (γH2AX 焦点) 和 DNA 复制 (EdU 掺入) 之间的依赖性。 Cpt 诱导 γH2AX 焦点，可能报告 DNA 双链断裂 (DSB) 的形成，几乎只在 DNA 复制位点形成。这一发现与 DNA 拓扑异构酶 I (topo1) 抑制剂在移动复制叉与 Cpt 稳定的 topo1-DNA“可裂解复合物”碰撞位点诱导 DSB 的已知机制一致。尽管在 H2O2 作用下的细胞 S 期中发现 H2AX 组蛋白磷酸化水平升高，但只有一小部分 γH2AX 焦点与 DNA 复制位点一致。因此，H2O2 诱导的 H2AX 磷酸化水平升高并不是 DNA 复制叉移动位点形成 DNA 损伤的直接结果。这些数据表明，H2O2 诱导的氧化应激和 H2O2 诱导的主要损伤（8-oxo-7,8-二氢鸟苷）的形成会抑制全局复制，并在距复制叉不同距离处触发 γH2AX 的形成。 DNA 复制位点和 γH2AX 焦点频率的定量分析还表明，Cpt 复制叉的停滞会导致新 DNA 复制起点的激活。
A method of quantitative analysis of spatial (3D) relationship between discrete nuclear events detected by confocal microscopy is described and applied in analysis of a dependence between sites of DNA damage signaling (γH2AX foci) and DNA replication (EdU incorporation) in cells subjected to treatments with camptothecin (Cpt) or hydrogen peroxide (H2O2). Cpt induces γH2AX foci, likely reporting formation of DNA double-strand breaks (DSBs), almost exclusively at sites of DNA replication. This finding is consistent with the known mechanism of induction of DSBs by DNA topoisomerase I (topo1) inhibitors at the sites of collisions of the moving replication forks with topo1-DNA “cleavable complexes” stabilized by Cpt. Whereas an increased level of H2AX histone phosphorylation is seen in S-phase of cells subjected to H2O2, only a minor proportion of γH2AX foci coincide with DNA replication sites. Thus, the increased level of H2AX phosphorylation induced by H2O2 is not a direct consequence of formation of DNA lesions at the sites of moving DNA replication forks. These data suggest that oxidative stress induced by H2O2 and formation of the primary H2O2-induced lesions (8–oxo-7,8-dihydroguanosine) inhibits replication globally and triggers formation of γH2AX at various distances from replication forks. Quantitative analysis of a frequency of DNA replication sites and γH2AX foci suggests also that stalling of replicating forks by Cpt leads to activation of new DNA replication origins.
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DOI：
10.1083/jcb.149.2.271
发表时间：
2000-04-17
期刊：
The Journal of cell biology
影响因子：
--
作者：
Leonhardt H;Rahn HP;Weinzierl P;Sporbert A;Cremer T;Zink D;Cardoso MC
通讯作者：
Cardoso MC
影响因子：
3.7
作者：
Zhao, Hong;Tanaka, Toshiki;Darzynkiewicz, Zbigniew
通讯作者：
Darzynkiewicz, Zbigniew
影响因子：
3.7
作者：
Furia, Laura;Pelicci, Pier Giuseppe;Faretta, Mario
通讯作者：
Faretta, Mario
影响因子：
4.3
作者：
Tanaka, Toshiki;Halicka, H. Dorota;Darzynkiewicz, Zbigniew
通讯作者：
Darzynkiewicz, Zbigniew
DOI：
10.1046/j.1525-1373.1999.d01-141.x
发表时间：
1999-12-01
影响因子：
--
作者：
Aust, AE;Eveleigh, JF
通讯作者：
Eveleigh, JF