Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014, USA.
J Virol. 2010 May;84(10):5260-9. doi: 10.1128/JVI.02733-09. Epub 2010 Feb 24.
Human cytomegalovirus (HCMV) infection has been shown to activate the mTORC1 signaling pathway. However, the phosphorylation of mTORC1 targets is differentially sensitive to the mTORC1 inhibitor rapamycin, and the drug inhibits HCMV replication to a modest extent. Using Torin1, a newly developed inhibitor that targets the catalytic site of mTOR kinase, we show that HCMV replication requires both rapamycin-sensitive and rapamycin-resistant mTOR activity. The treatment of infected cells with Torin1 inhibits the phosphorylation of rapamycin-sensitive and rapamycin-resistant mTOR targets and markedly blocks the production of virus progeny. The blockade of mTOR signaling with Torin1, but not rapamycin, disrupts the assembly of the eIF4F complex and increases the association of the translational repressor 4EBP1 to the 7-methylguanosine cap-binding complex. Torin1 does not affect HCMV entry and only modestly reduces the accumulation of the immediate-early and early viral proteins that were tested despite the disruption of the eIF4F complex. In contrast, Torin1 significantly decreases the accumulation of viral DNA and the pUL99 viral late protein. Similar mTOR signaling events were observed during murine cytomegalovirus (MCMV) infection, and we utilized murine fibroblasts containing several different mutations to dissect the mechanism by which Torin1 inhibits MCMV replication. This approach demonstrated that mTORC2 and the Akt1 and Akt2 kinases are not required for the Torin1-mediated inhibition of cytomegalovirus replication. The inhibition of MCMV replication by Torin1 was rescued in cells lacking 4EBP1, demonstrating that the inactivation of 4EBP1 by mTORC1 is critical for cytomegalovirus replication. Finally, we show that Torin1 inhibits the replication of representative members of the alpha-, beta-, and gammaherpesvirus families, demonstrating the potential of mTOR kinase inhibitors as broad-spectrum antiviral agents.
人类巨细胞病毒(HCMV)感染已被证明能激活 mTORC1 信号通路。然而,mTORC1 靶标的磷酸化对 mTORC1 抑制剂雷帕霉素的敏感性不同,且该药物对 HCMV 的抑制作用仅为中等程度。我们使用新开发的靶向 mTOR 激酶催化位点的抑制剂 Torin1,表明 HCMV 的复制需要雷帕霉素敏感和雷帕霉素抗性的 mTOR 活性。用 Torin1 处理感染细胞可抑制雷帕霉素敏感和雷帕霉素抗性 mTOR 靶标的磷酸化,并显著阻断病毒产物的产生。用 Torin1 阻断 mTOR 信号会破坏 eIF4F 复合物的组装,并增加翻译抑制因子 4EBP1 与 7-甲基鸟苷帽结合复合物的结合。Torin1 不影响 HCMV 的进入,尽管破坏了 eIF4F 复合物,但仅适度减少所测试的即刻早期和早期病毒蛋白的积累。相比之下,Torin1 显著减少病毒 DNA 和 pUL99 病毒晚期蛋白的积累。在鼠巨细胞病毒(MCMV)感染期间观察到类似的 mTOR 信号事件,我们利用含有几种不同突变的鼠成纤维细胞来剖析 Torin1 抑制 MCMV 复制的机制。这种方法表明,mTORC2 和 Akt1 和 Akt2 激酶对于 Torin1 介导的抑制巨细胞病毒复制不是必需的。Torin1 抑制 MCMV 复制在缺乏 4EBP1 的细胞中被挽救,表明 mTORC1 对 4EBP1 的失活对于巨细胞病毒复制至关重要。最后,我们表明 Torin1 抑制代表α、β和γ疱疹病毒家族的成员的复制,表明 mTOR 激酶抑制剂作为广谱抗病毒药物的潜力。
Rev Esp Quimioter. 2023-10
Nat Commun. 2021-10-14
Adv Chronic Kidney Dis. 2019-5
Cell Cycle. 2009-12-14
Cancer Res. 2008-10-15
Curr Top Microbiol Immunol. 2008