The dynamics of Ku70/80 and DNA-PKcs at DSBs induced by ionizing radiation is dependent on the complexity of damage.
The dynamics of Ku70/80 and DNA-PKcs at DSBs induced by ionizing radiation is dependent on the complexity of damage.
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DOI：
10.1093/nar/gks879
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发表时间：
2012-11
影响因子：
14.9
通讯作者：
O'Neill P
中科院分区：
文献类型：
--
作者：
Reynolds P;Anderson JA;Harper JV;Hill MA;Botchway SW;Parker AW;O'Neill P
DNA双链断裂（DSBs）是生物学上最重要的细胞损伤之一，具有不同程度的化学复杂性。化学更复杂的DSB的可修复性是低效的，这一概念导致了DSB复杂性的程度是生物后果严重程度的基础。非同源末端连接（non-homologous end joining， NHEJ）对dsb的修复作用已被广泛研究，但与简单dsb相比，更复杂的dsb是否需要不同的NHEJ蛋白亚群进行修复尚不清楚。为了解决这个问题，我们使用超软x射线（USX）或多光子近红外（NIR）激光照射在荧光标记的哺乳动物细胞（Ku80-EGFP， DNA-PKcs-YFP或XRCC4-GFP， NHEJ的关键蛋白）中诱导dsb。我们实时发现，USX或近红外微束辐照诱导的简单dsb可以通过Ku70/80和XRCC4/连接酶IV/XLF快速修复。相比之下，具有更大化学复杂性的dsb不仅涉及Ku70/80和XRCC4/连接酶IV/XLF，还涉及DNA-PKcs，其修复速度较慢。共济失调毛细血管扩张症突变抑制仅延缓了需要DNA-PKcs的化学更复杂的dsb的修复。综上所述，NHEJ对DSB的修复受到高度调控，修复的途径选择和动力学取决于DSB的化学复杂性。
DNA double-strand breaks (DSBs) are biologically one of the most important cellular lesions and possess varying degrees of chemical complexity. The notion that the repairability of more chemically complex DSBs is inefficient led to the concept that the extent of DSB complexity underlies the severity of the biological consequences. The repair of DSBs by non-homologous end joining (NHEJ) has been extensively studied but it remains unknown whether more complex DSBs require a different sub-set of NHEJ protein for their repair compared with simple DSBs. To address this, we have induced DSBs in fluorescently tagged mammalian cells (Ku80-EGFP, DNA-PKcs-YFP or XRCC4-GFP, key proteins in NHEJ) using ultra-soft X-rays (USX) or multi-photon near infrared (NIR) laser irradiation. We have shown in real-time that simple DSBs, induced by USX or NIR microbeam irradiation, are repaired rapidly involving Ku70/80 and XRCC4/Ligase IV/XLF. In contrast, DSBs with greater chemical complexity are repaired slowly involving not only Ku70/80 and XRCC4/Ligase IV/XLF but also DNA-PKcs. Ataxia telangiectasia-mutated inhibition only retards repair of the more chemically complex DSBs which require DNA-PKcs. In summary, the repair of DSBs by NHEJ is highly regulated with pathway choice and kinetics of repair dependent on the chemical complexity of the DSB.
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影响因子：
4.8
作者：
Chen, Benjamin P. C.;Uematsu, Naoya;Chen, David J.
通讯作者：
Chen, David J.
DOI：
10.1083/jcb.200510130
发表时间：
2006-04-24
期刊：
The Journal of cell biology
影响因子：
--
作者：
Bekker-Jensen S;Lukas C;Kitagawa R;Melander F;Kastan MB;Bartek J;Lukas J
通讯作者：
Lukas J
影响因子：
4.8
作者：
Chan, DW;LeesMiller, SP
通讯作者：
LeesMiller, SP
DOI：
10.1073/pnas.1016045108
发表时间：
2011-05-17
影响因子：
11.1
作者：
Asaithamby, Aroumougame;Hu, Burong;Chen, David J.
通讯作者：
Chen, David J.
影响因子：
3.4
作者：
Chang, CC;Sun, W;Trosko, JE
通讯作者：
Trosko, JE