Bocavirus Infection Induces a DNA Damage Response That Facilitates Viral DNA Replication and Mediates Cell Death
Bocavirus Infection Induces a DNA Damage Response That Facilitates Viral DNA Replication and Mediates Cell Death
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DOI：
10.1128/jvi.01534-10
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发表时间：
2011-01-01
影响因子：
5.4
通讯作者：
Qiu, Jianming
中科院分区：
文献类型：
--
作者：
Luo, Yong;Chen, Aaron Yun;Qiu, Jianming
犬细小病毒（MVC）是一种自主性细小病毒，在Walter Reed/3873 D（WRD）犬细胞中无需辅助病毒即可有效复制。我们以前的研究表明，MVC感染可诱导WRD细胞发生凋亡和G（2）/M期阻滞。然而，造成这些影响的机制尚未确定。在这里，我们报告说，MVC感染触发了受感染细胞的DNA损伤反应，从H2 AX和RPA 32的磷酸化可以看出。我们发现ATM（共济失调毛细血管扩张突变激酶）和ATR（ATM和Rad 3相关激酶）在MVC感染的WRD细胞中磷酸化，并证实ATM激活负责H2 AX的磷酸化，而ATR激活是RPA 32磷酸化所必需的。在MVC感染的细胞中，ATM活化的药理学抑制和ATM的敲低均导致细胞死亡的显著减少、细胞周期停滞的适度校正，并且最重要的是，MVC DNA复制和子代病毒产生的减少。用ATR靶向的小干扰RNA（siRNA）进行的平行实验没有效果。此外，我们发现这种ATM介导的细胞死亡是p53依赖性的。此外，我们将Mre 11-Rad 50-Nbs 1（MRN）复合物（ATM介导的DNA损伤反应途径的主要介质和底物）定位于感染期间的MVC复制中心，并表明Mre 11敲低导致MVC DNA复制减少。我们的研究结果是第一个支持这样的观点，即自主细小病毒能够劫持宿主DNA损伤机制进行自身复制和诱导细胞死亡。
Minute virus of canines (MVC) is an autonomous parvovirus that replicates efficiently without helper viruses in Walter Reed/3873D (WRD) canine cells. We previously showed that MVC infection induces mitochondrion-mediated apoptosis and G(2)/M-phase arrest in infected WRD cells. However, the mechanism responsible for these effects has not been established. Here, we report that MVC infection triggers a DNA damage response in infected cells, as evident from phosphorylation of H2AX and RPA32. We discovered that both ATM (ataxia telangiectasia-mutated kinase) and ATR (ATM- and Rad3-related kinase) were phosphorylated in MVC-infected WRD cells and confirmed that ATM activation was responsible for the phosphorylation of H2AX, whereas ATR activation was required for the phosphorylation of RPA32. Both pharmacological inhibition of ATM activation and knockdown of ATM in MVC-infected cells led to a significant reduction in cell death, a moderate correction of cell cycle arrest, and most importantly, a reduction in MVC DNA replication and progeny virus production. Parallel experiments with an ATR-targeted small interfering RNA (siRNA) had no effect. Moreover, we identified that this ATM-mediated cell death is p53 dependent. In addition, we localized the Mre11-Rad50-Nbs1 (MRN) complex, the major mediator as well as a substrate of the ATM-mediated DNA damage response pathway to MVC replication centers during infection, and show that Mre11 knockdown led to a reduction in MVC DNA replication. Our findings are the first to support the notion that an autonomous parvovirus is able to hijack the host DNA damage machinery for its own replication and for the induction of cell death.