Wang Wenshi, Wang Yijin, Debing Yannick, Zhou Xinying, Yin Yuebang, Xu Lei, Herrera Carrillo Elena, Brandsma Johannes H, Poot Raymond A, Berkhout Ben, Neyts Johan, Peppelenbosch Maikel P, Pan Qiuwei
Department of Gastroenterology and Hepatology, Postgraduate School Molecular Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium.
Antiviral Res. 2017 Apr;140:1-12. doi: 10.1016/j.antiviral.2017.01.005. Epub 2017 Jan 8.
Although hepatitis E has emerged as a global health issue, there is limited knowledge of its infection biology and no FDA-approved medication is available. Aiming to investigate the role of protein kinases in hepatitis E virus (HEV) infection and to identify potential antiviral targets, we screened a library of pharmacological kinase inhibitors in a cell culture model, a subgenomic HEV replicon containing luciferase reporter. We identified protein kinase C alpha (PKCα) as an essential cell host factor restricting HEV replication. Both specific inhibitor and shRNA-mediated knockdown of PKCα enhanced HEV replication. Conversely, over-expression of the activated form of PKCα or treatment with its pharmacological activator strongly inhibited HEV replication. Interestingly, upon the stimulation by its activator, PKCα efficiently activates its downstream Activator Protein 1 (AP-1) pathway, leading to the induction of antiviral interferon-stimulated genes (ISGs). This process is independent of the JAK-STAT machinery and interferon production. However, PKCα induced HEV inhibition appears independent of the AP1 cascade. The discovery that activated PKCα restricts HEV replication reveals new insight of HEV-host interactions and provides new target for antiviral drug development.
尽管戊型肝炎已成为一个全球健康问题，但对其感染生物学的了解有限，且尚无美国食品药品监督管理局（FDA）批准的药物。为了研究蛋白激酶在戊型肝炎病毒（HEV）感染中的作用并确定潜在的抗病毒靶点，我们在一个细胞培养模型中筛选了一个药理学激酶抑制剂文库，该模型是一个含有荧光素酶报告基因的亚基因组HEV复制子。我们确定蛋白激酶Cα（PKCα）是限制HEV复制的一种重要细胞宿主因子。PKCα的特异性抑制剂和shRNA介导的敲低均增强了HEV复制。相反，PKCα活化形式的过表达或用其药理学激活剂处理则强烈抑制HEV复制。有趣的是，在其激活剂的刺激下，PKCα有效地激活其下游的激活蛋白1（AP-1）途径，导致抗病毒干扰素刺激基因（ISGs）的诱导。这个过程独立于JAK-STAT机制和干扰素产生。然而，PKCα诱导的HEV抑制似乎独立于AP1级联反应。活化的PKCα限制HEV复制这一发现揭示了HEV与宿主相互作用的新见解，并为抗病毒药物开发提供了新靶点。
