Barrier-to-Autointegration Factor 1 Protects against a Basal cGAS-STING Response
Barrier-to-Autointegration Factor 1 Protects against a Basal cGAS-STING Response
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DOI：
10.1128/mbio.00136-20
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发表时间：
2020-03-01
期刊：
影响因子：
6.4
通讯作者：
Diamond, Michael S.
中科院分区：
文献类型：
--
作者：
Ma, Hongming;Qian, Wei;Diamond, Michael S.
尽管激活细胞固有抗病毒反应的病原体识别受体通路已经被很好地描述，但关于宿主如何调节这种反应以防止持续的信号传递和可能的免疫介导的损伤，人们知之甚少。使用全基因组CRISPR-Cas9筛选方法确定调节干扰素刺激基因(ISG)表达的宿主因子，我们确定DNA结合蛋白Barrier-to-AutoIntegration factor1(Banf1)是一种先前描述的逆转录病毒整合抑制因子，是基础细胞内源性免疫的调节器。通过基因编辑去除Banf1导致寄主防御基因附近的染色质激活，相关的ISGs表达增加，包括Oas2、Rsad2(毒蛇蛋白)、Ifit1和ISG15。Banf1缺陷细胞的表型通过依赖于cGAS、STING和IRF3的信号轴发生，与RNA和DNA病毒感染的减少有关，而在Banf1互补的细胞中则相反。共聚焦显微镜和生化研究显示，在基线水平，Banf1的表达缺失导致胞浆双链DNA水平升高。我们的研究确定了Banf1在调节细胞质DNA水平和依赖cGAS的ISG动态平衡中的未知作用，并提出了促进或抑制细胞固有免疫反应的可能治疗方向。虽然干扰素信号通路是限制多种病毒病原体感染的关键宿主机制，但其在基线或免疫反应背景下的不受限制的活性可导致宿主细胞的损伤和损伤。在这里，我们使用了全基因组CRISPR-Cas9筛查，并确定DNA结合蛋白Barrier-to-AutoIntegration factor1(Banf1)是基础细胞固有免疫的调节器。在基线水平，Banf1表达缺失导致胞浆双链DNA水平升高，从而通过cGAS-STING-IRF3轴触发干扰素刺激的基因表达，而不需要I型干扰素或STAT1信号。我们的实验定义了一个调控网络，在该网络中，Banf1通过防止自身DNA在细胞质中积累来限制基础炎症。
Although the pathogen recognition receptor pathways that activate cell-intrinsic antiviral responses are well delineated, less is known about how the host regulates this response to prevent sustained signaling and possible immune-mediated damage. Using a genome-wide CRISPR-Cas9 screening approach to identify host factors that modulate interferon-stimulated gene (ISG) expression, we identified the DNA binding protein Barrier-to-autointegration factor 1 (Banf1), a previously described inhibitor of retrovirus integration, as a modulator of basal cell-intrinsic immunity. Ablation of Banf1 by gene editing resulted in chromatin activation near host defense genes with associated increased expression of ISGs, including Oas2, Rsad2 (viperin), Ifit1, and ISG15. The phenotype in Banf1-deficient cells occurred through a cGAS-, STING-, and IRF3-dependent signaling axis, was associated with reduced infection of RNA and DNA viruses, and was reversed in Banf1 complemented cells. Confocal microscopy and biochemical studies revealed that a loss of Banf1 expression resulted in higher level of cytosolic double-stranded DNA at baseline. Our study identifies an undescribed role for Banf1 in regulating the levels of cytoplasmic DNA and cGAS-dependent ISG homeostasis and suggests possible therapeutic directions for promoting or inhibiting cell-intrinsic innate immune responses.IMPORTANCE Although the interferon (IFN) signaling pathway is a key host mechanism to restrict infection of a diverse range of viral pathogens, its unrestrained activity either at baseline or in the context of an immune response can result in host cell damage and injury. Here, we used a genome-wide CRISPR-Cas9 screen and identified the DNA binding protein Barrier-to-autointegration factor 1 (Banf1) as a modulator of basal cell-intrinsic immunity. A loss of Banf1 expression resulted in higher level of cytosolic double-stranded DNA at baseline, which triggered IFN-stimulated gene expression via a cGAS-STING-IRF3 axis that did not require type I IFN or STAT1 signaling. Our experiments define a regulatory network in which Banf1 limits basal inflammation by preventing self DNA accumulation in the cytosol.