Cellular DNA repair cofactors affecting hepatitis B virus infection and replication.
Cellular DNA repair cofactors affecting hepatitis B virus infection and replication.
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DOI：
10.3748/wjg.14.5059
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发表时间：
2008-08
影响因子：
4.3
通讯作者：
F. Zhao;Ningbo Hou;Ting Song;Xiang He;Zirui Zheng;Q. Ma;Li Li-Li;Yan-hong Zhang;H. Zhong
中科院分区：
文献类型：
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作者：
F. Zhao;Ningbo Hou;Ting Song;Xiang He;Zirui Zheng;Q. Ma;Li Li-Li;Yan-hong Zhang;H. Zhong
目的探讨乙型肝炎病毒(乙肝病毒)感染是否激活DNA损伤应答和DNA修复辅助因子抑制乙肝病毒感染和复制。方法以人肝细胞系HL7702为研究对象。免疫印迹法检测感染和未感染细胞中共济失调毛细血管扩张突变(ATM)-Rad3相关蛋白(ATR)、p21的表达和Chk1、P53、H2AX、ATM的磷酸化水平。将特定的短RNAi寡核苷酸导入HL7702细胞，诱导瞬时ATR基因敲除。研究ATR-ATM化学抑制剂咖啡因(CF)和茶碱(TP)或Chk1抑制剂7-羟基黄孢菌素(UCN01)是否抑制细胞DNA损伤反应，以及MG132是否抑制蛋白酶体。结果HBVDNA单链断裂后，ATR检查点通路被激活。ATR基因敲除细胞使HBVDNA产量降低，提示感染和复制可激活和利用激活的DNA损伤反应。CF/TP或UCN01使HBVDNA产量分别减少70%和80%。乙肝病毒通过降解p21来阻断依赖ATR的DNA损伤信号通路，而在感染前引入p21蛋白降低了HBVDNA产量。与此结果一致的是，MG132处理后p21的积累也显著降低了HBVDNA产量。结论通过抑制乙肝病毒复制所需的细胞基因或恢复被乙肝病毒消除的应答，可以通过靶向宿主细胞蛋白的治疗方法来治疗乙肝病毒感染，从而为预防和治疗乙肝病毒感染提供了一种潜在的途径。
AIM To investigate whether hepatitis B virus (HBV) infection activates DNA damage response and DNA repair cofactors inhibit HBV infection and replication. METHODS Human hepatocyte cell line HL7702 was studied. Immunoblotting was performed to test the expression of ataxia telangiectasia-mutated (ATM)-Rad3-related protein (ATR), p21 and the level of phosphorylation of Chk1, p53, H2AX, ATM in HBV-infected or non-infected-cells. Special short RNAi oligos was transfected to induce transient ATR knockdown in HL7702. ATR-ATM chemical inhibitors caffeine (CF) and theophylline (TP), or Chk1 inhibitor 7-hydroxystaurosporine (UCN01) was studied to determine whether they suppress cellular DNA damage response and MG132 inhibits proteasome. RESULTS The ATR checkpoint pathway, responding to single-strand breaks in DNA, was activated in response to HBV infection. ATR knockdown cells decreased the HBV DNA yields, implying that HBV infection and replication could activate and exploit the activated DNA damage response. CF/TP or UCN01 reduced the HBV DNA yield by 70% and 80%, respectively. HBV abrogated the ATR-dependent DNA damage signaling pathway by degrading p21, and introduction of the p21 protein before HBV infection reduced the HBV DNA yield. Consistent with this result, p21 accumulation after MG132 treatment also sharply decreased the HBV DNA yield. CONCLUSION HBV infection can be treated with therapeutic approaches targeting host cell proteins by inhibiting a cellular gene required for HBV replication or by restoring a response abrogated by HBV, thus providing a potential approach to the prevention and treatment of HBV infection.