Inhibition of anti-viral stress granule formation by coronavirus endoribonuclease nsp15 ensures efficient virus replication.
Inhibition of anti-viral stress granule formation by coronavirus endoribonuclease nsp15 ensures efficient virus replication.
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冠状病毒内切核糖核酸酶 nsp15 抑制抗病毒应激颗粒形成，确保病毒有效复制
DOI：
10.1371/journal.ppat.1008690
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发表时间：
2021-03
期刊：
影响因子：
6.7
通讯作者：
Liao Y
中科院分区：
文献类型：
--
作者：
Gao B;Gong X;Fang S;Weng W;Wang H;Chu H;Sun Y;Meng C;Tan L;Song C;Qiu X;Liu W;Forlenza M;Ding C;Liao Y
细胞质应激颗粒（SG）通常由应激诱导的翻译停滞触发，用于储存mRNA。最近，已经表明，SG发挥抗病毒功能，由于它们参与蛋白质合成关闭和募集先天免疫信号传导中间体。冠状病毒是最大的RNA病毒，对公共安全和动物健康构成巨大威胁;然而，SGs在冠状病毒感染中的意义在很大程度上是未知的。传染性支气管炎病毒（Infectious Bronchitis Virus，IBV）是20世纪30年代发现的第一种冠状病毒，多年来一直在家禽养殖场流行。在这项研究中，我们提供的证据表明，IBV克服宿主的抗病毒反应，通过抑制SG的形成，通过病毒编码的核糖核酸内切酶nsp 15。通过免疫荧光分析，我们观察到，IBV感染不仅没有触发SGs的形成在约80%的感染细胞，但也损害了SGs的形成触发热休克，亚砷酸钠，或NaCl刺激。我们进一步证明了nsp 15的内在核糖核酸内切酶活性是干扰SGs形成的原因。事实上，nsp 15缺陷型重组IBV（rIBV-nsp 15-H238 A）显著诱导SGs的形成，沿着dsRNA的积累和PKR的激活，而野生型IBV不能这样做。因此，rIBV-nsp 15-H238 A感染强烈触发IFN-β的转录，这反过来极大地影响了rIBV-nsp 15-H238 A的复制。进一步的分析表明，SG作为抗病毒枢纽发挥作用，如通过减弱的IRF 3-IFN应答和SG缺陷细胞中IBV产生的增加所证明的。其他证据包括模式识别受体（PRR）和信号传导中间体聚集到IBV诱导的SG。总的来说，我们的数据表明，IBV的核糖核酸内切酶nsp 15通过调节病毒dsRNA的积累和拮抗PKR的活化来干扰抗病毒中心SG的形成，最终确保生产性病毒复制。我们进一步证明了来自PEDV、TGEV、SARS-CoV和SARS-CoV-2的nsp 15具有干扰化学诱导的SG形成的保守功能。因此，我们推测冠状病毒采用类似的nsp 15介导的机制来拮抗宿主抗病毒SG的形成，以确保有效的病毒复制。
Cytoplasmic stress granules (SGs) are generally triggered by stress-induced translation arrest for storing mRNAs. Recently, it has been shown that SGs exert anti-viral functions due to their involvement in protein synthesis shut off and recruitment of innate immune signaling intermediates. The largest RNA viruses, coronaviruses, impose great threat to public safety and animal health; however, the significance of SGs in coronavirus infection is largely unknown. Infectious Bronchitis Virus (IBV) is the first identified coronavirus in 1930s and has been prevalent in poultry farm for many years. In this study, we provided evidence that IBV overcomes the host antiviral response by inhibiting SGs formation via the virus-encoded endoribonuclease nsp15. By immunofluorescence analysis, we observed that IBV infection not only did not trigger SGs formation in approximately 80% of the infected cells, but also impaired the formation of SGs triggered by heat shock, sodium arsenite, or NaCl stimuli. We further demonstrated that the intrinsic endoribonuclease activity of nsp15 was responsible for the interference of SGs formation. In fact, nsp15-defective recombinant IBV (rIBV-nsp15-H238A) greatly induced the formation of SGs, along with accumulation of dsRNA and activation of PKR, whereas wild type IBV failed to do so. Consequently, infection with rIBV-nsp15-H238A strongly triggered transcription of IFN-β which in turn greatly affected rIBV-nsp15-H238A replication. Further analysis showed that SGs function as an antiviral hub, as demonstrated by the attenuated IRF3-IFN response and increased production of IBV in SG-defective cells. Additional evidence includes the aggregation of pattern recognition receptors (PRRs) and signaling intermediates to the IBV-induced SGs. Collectively, our data demonstrate that the endoribonuclease nsp15 of IBV interferes with the formation of antiviral hub SGs by regulating the accumulation of viral dsRNA and by antagonizing the activation of PKR, eventually ensuring productive virus replication. We further demonstrated that nsp15s from PEDV, TGEV, SARS-CoV, and SARS-CoV-2 harbor the conserved function to interfere with the formation of chemically-induced SGs. Thus, we speculate that coronaviruses employ similar nsp15-mediated mechanisms to antagonize the host anti-viral SGs formation to ensure efficient virus replication.
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一种具有新故事的“旧”蛋白质：冠状病毒内切核糖核酸酶对于逃避宿主抗病毒防御非常重要。
影响因子：
3.7
作者：
Deng X;Baker SC
通讯作者：
Baker SC
影响因子：
4.6
作者：
Dabo S;Maillard P;Collados Rodriguez M;Hansen MD;Mazouz S;Bigot DJ;Tible M;Janvier G;Helynck O;Cassonnet P;Jacob Y;Bellalou J;Gatignol A;Patel RC;Hugon J;Munier-Lehmann H;Meurs EF
通讯作者：
Meurs EF
影响因子：
16
作者：
Harding, HP;Zhang, YH;Ron, D
通讯作者：
Ron, D
影响因子：
9.2
作者：
Deng, J;Harding, HP;Sonenberg, N
通讯作者：
Sonenberg, N
影响因子：
6.4
作者：
Angelini MM;Akhlaghpour M;Neuman BW;Buchmeier MJ
通讯作者：
Buchmeier MJ