A Novel Phenotype Links HIV-1 Capsid Stability to cGAS-Mediated DNA Sensing.
A Novel Phenotype Links HIV-1 Capsid Stability to cGAS-Mediated DNA Sensing.
复制标题
一种新表型将 HIV-1 衣壳稳定性与 cGAS 介导的 DNA 传感联系起来。
DOI：
10.1128/jvi.00706-19
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发表时间：
2019
影响因子：
5.4
通讯作者：
Yamashita,Masahiro
中科院分区：
文献类型：
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作者：
Siddiqui,MohammadAdnan;Saito,Akatsuki;Halambage,UpulD;Ferhadian,Damien;Fischer,DouglasK;Francis,AshwanthC;Melikyan,GregoryB;Ambrose,Zandrea;Aiken,Christopher;Yamashita,Masahiro
HIV-1衣壳执行由衣壳稳定性和宿主因子调节的基本功能。相反，增加知识的功能作用的衣壳蛋白相互作用的宿主蛋白在postentry步骤，了解较少的衣壳稳定性及其对细胞内事件的影响。在这里，使用抗病毒化合物PF-3450074（PF 74）作为衣壳功能的探针，我们发现了衣壳稳定性的新表型，其对DNA传感器cGAS对病毒DNA的先天传感具有深远影响。衣壳蛋白中的单一突变R143 A赋予对高浓度PF 74的抗性，而不影响衣壳与PF 74的结合。无细胞测定表明，R143 A突变体部分抵消了PF 74的衣壳去稳定化活性，指出衣壳稳定化是R143 A突变体的抗性机制。在单核细胞THP-1细胞中，R143 A病毒而非野生型病毒抑制cGAS依赖性先天免疫激活。这些结果表明衣壳稳定化改善了病毒DNA对先天感应的屏蔽。我们发现，一个自然发生的传播创始人（T/F）变异共享相同的属性作为R143 A突变体方面的PF 74电阻和DNA传感。成像分析揭示了这种T/F变体和R143 A突变体的延迟脱包被动力学。这种T/F变体的所有这些表型由位于衣壳六聚体之间的三聚体界面处的遗传多态性控制，从而连接这些衣壳依赖性。总的来说，这项工作在功能上连接衣壳的稳定性先天感应的病毒DNA，并揭示了自然发生的表型变异HIV-1衣壳stability.IMPORTANCEThe HIV-1衣壳，这是由个别病毒衣壳蛋白（CA），是一个目标的一些抗病毒化合物，包括小分子抑制剂PF 74。在本研究中，我们利用PF 74来鉴定显示增加的衣壳稳定性的传播/创始者（T/F）菌株。有趣的是，在其他T/F菌株诱导I型干扰素的条件下，PF 74抗性变体阻止了cGAS依赖性先天免疫激活。因此，这些观察结果揭示了一种新的CA特异性表型，其将衣壳稳定性与细胞溶质DNA传感器对病毒DNA的识别相结合。
The HIV-1 capsid executes essential functions that are regulated by capsid stability and host factors. In contrast to increasing knowledge on functional roles of capsid-interacting host proteins during postentry steps, less is known about capsid stability and its impact on intracellular events. Here, using the antiviral compound PF-3450074 (PF74) as a probe for capsid function, we uncovered a novel phenotype of capsid stability that has a profound effect on innate sensing of viral DNA by the DNA sensor cGAS. A single mutation, R143A, in the capsid protein conferred resistance to high concentrations of PF74, without affecting capsid binding to PF74. A cell-free assay showed that the R143A mutant partially counteracted the capsid-destabilizing activity of PF74, pointing to capsid stabilization as a resistance mechanism for the R143A mutant. In monocytic THP-1 cells, the R143A virus, but not the wild-type virus, suppressed cGAS-dependent innate immune activation. These results suggest that capsid stabilization improves the shielding of viral DNA from innate sensing. We found that a naturally occurring transmitted founder (T/F) variant shares the same properties as the R143A mutant with respect to PF74 resistance and DNA sensing. Imaging assays revealed delayed uncoating kinetics of this T/F variant and the R143A mutant. All these phenotypes of this T/F variant were controlled by a genetic polymorphism located at the trimeric interface between capsid hexamers, thus linking these capsid-dependent properties. Overall, this work functionally connects capsid stability to innate sensing of viral DNA and reveals naturally occurring phenotypic variation in HIV-1 capsid stability.IMPORTANCEThe HIV-1 capsid, which is made from individual viral capsid proteins (CA), is a target for a number of antiviral compounds, including the small-molecule inhibitor PF74. In the present study, we utilized PF74 to identify a transmitted/founder (T/F) strain that shows increased capsid stability. Interestingly, PF74-resistant variants prevented cGAS-dependent innate immune activation under a condition where the other T/F strains induced type I interferon. These observations thus reveal a new CA-specific phenotype that couples capsid stability to viral DNA recognition by cytosolic DNA sensors.