The PERK/PKR-eIF2α Pathway Negatively Regulates Porcine Hemagglutinating Encephalomyelitis Virus Replication by Attenuating Global Protein Translation and Facilitating Stress Granule Formation.
The PERK/PKR-eIF2α Pathway Negatively Regulates Porcine Hemagglutinating Encephalomyelitis Virus Replication by Attenuating Global Protein Translation and Facilitating Stress Granule Formation.
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PERK/PKR-eIF2α 通路通过减弱全局蛋白翻译和促进应激颗粒形成来负调节猪血凝性脑脊髓炎病毒复制
DOI：
10.1128/jvi.01695-21
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发表时间：
2022-01-12
影响因子：
5.4
通讯作者：
He W
中科院分区：
文献类型：
--
作者：
Shi J;Li Z;Xu R;Zhang J;Zhou Q;Gao R;Lu H;Lan Y;Zhao K;He H;Gao F;He W
冠状病毒疾病是由对人类和动物重要的不同冠状病毒引起的，具体的治疗方法极其有限。 ERS 可以激活 UPR 来调节病毒复制和宿主先天反应，在冠状病毒感染的细胞中经常发生。摘要 冠状病毒的复制与感染细胞的内质网（ER）密切相关，包括严重急性呼吸综合征冠状病毒（SARS-CoV）、中东呼吸综合征冠状病毒（MERS-CoV）和最近出现的严重急性呼吸综合征冠状病毒2（SARS-CoV-2）。由内质网应激（ERS）介导的未折叠蛋白反应（UPR）是冠状病毒感染细胞的典型结果，与冠状病毒的特征密切相关。然而，人们对病毒诱导的 ERS 和冠状病毒复制之间的相互作用知之甚少。在这里，我们证明了β冠状病毒猪血凝性脑脊髓炎病毒（PHEV）的感染诱导了ERS，并在体外和体内触发了UPR信号通路的所有三个分支。此外，ERS 主要通过激活 UPR 的蛋白激酶 R 样 ER 激酶 (PERK) – 真核起始因子 2α (eIF2α) 轴来抑制小鼠神经 2a (N2a) 细胞中的 PHEV 复制。此外，另一种 eIF2α 磷酸化激酶，干扰素 (IFN) 诱导的双链 RNA 依赖性蛋白激酶 (PKR) 也被激活，并与 PERK 协同作用，减少 PHEV 复制。此外，我们证明 PERK/PKR-eIF2α 通路通过减弱整体蛋白质翻译来负向调节 PHEV 复制。磷酸化的 eIF2α 还促进应激颗粒 (SG) 的形成，从而抑制 PHEV 复制。总之，我们的研究展示了宿主对入侵病原体的先天反应的一个重要方面，并揭示了抗病毒药物有吸引力的宿主靶标（例如 PERK、PKR 和 eIF2α）。重要性冠状病毒疾病是由对人类和动物重要的不同冠状病毒引起的，具体的治疗方法极其有限。 ERS 可以激活 UPR 来调节病毒复制和宿主先天反应，在冠状病毒感染的细胞中经常发生。 PHEV 是一种嗜神经性乙型冠状病毒，会导致神经细胞损伤，从而导致哺乳仔猪死亡率很高。然而，神经细胞中高度发达的ER是否在ERS中发挥抗病毒作用以及ERS如何调节病毒增殖尚不完全清楚。在这项研究中，我们发现 PHEV 感染在体外和体内均诱导 ERS 并激活 UPR，并且激活的 PERK/PKR-eIF2α 轴通过减弱整体蛋白翻译和促进 SG 形成来抑制 PHEV 复制。更好地了解冠状病毒诱导的 ERS 和 UPR 激活可能会揭示冠状病毒的致病机制，并有助于开发这些疾病的新治疗策略。
Coronavirus diseases are caused by different coronaviruses of importance in humans and animals, and specific treatments are extremely limited. ERS, which can activate the UPR to modulate viral replication and the host innate response, is a frequent occurrence in coronavirus-infected cells. ABSTRACT The replication of coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and the recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is closely associated with the endoplasmic reticulum (ER) of infected cells. The unfolded protein response (UPR), which is mediated by ER stress (ERS), is a typical outcome in coronavirus-infected cells and is closely associated with the characteristics of coronaviruses. However, the interaction between virus-induced ERS and coronavirus replication is poorly understood. Here, we demonstrate that infection with the betacoronavirus porcine hemagglutinating encephalomyelitis virus (PHEV) induced ERS and triggered all three branches of the UPR signaling pathway both in vitro and in vivo. In addition, ERS suppressed PHEV replication in mouse neuro-2a (N2a) cells primarily by activating the protein kinase R-like ER kinase (PERK)–eukaryotic initiation factor 2α (eIF2α) axis of the UPR. Moreover, another eIF2α phosphorylation kinase, interferon (IFN)-induced double-stranded RNA-dependent protein kinase (PKR), was also activated and acted cooperatively with PERK to decrease PHEV replication. Furthermore, we demonstrate that the PERK/PKR-eIF2α pathways negatively regulated PHEV replication by attenuating global protein translation. Phosphorylated eIF2α also promoted the formation of stress granules (SGs), which in turn repressed PHEV replication. In summary, our study presents a vital aspect of the host innate response to invading pathogens and reveals attractive host targets (e.g., PERK, PKR, and eIF2α) for antiviral drugs. IMPORTANCE Coronavirus diseases are caused by different coronaviruses of importance in humans and animals, and specific treatments are extremely limited. ERS, which can activate the UPR to modulate viral replication and the host innate response, is a frequent occurrence in coronavirus-infected cells. PHEV, a neurotropic betacoronavirus, causes nerve cell damage, which accounts for the high mortality rates in suckling piglets. However, it remains incompletely understood whether the highly developed ER in nerve cells plays an antiviral role in ERS and how ERS regulates viral proliferation. In this study, we found that PHEV infection induced ERS and activated the UPR both in vitro and in vivo and that the activated PERK/PKR-eIF2α axis inhibited PHEV replication through attenuating global protein translation and promoting SG formation. A better understanding of coronavirus-induced ERS and UPR activation may reveal the pathogenic mechanism of coronavirus and facilitate the development of new treatment strategies for these diseases.