Viral infections activate the powerful interferon (IFN) response that induces the expression of several hundred IFN stimulated genes (ISGs). The principal role of this extensive response is to create an unfavourable environment for virus replication and to limit spread; however, untangling the biological consequences of this large response is complicated. In addition to a seemingly high degree of redundancy, several ISGs are usually required in combination to limit infection as individual ISGs often have low to moderate antiviral activity. Furthermore, what ISG or combination of ISGs are antiviral for a given virus is usually not known. For these reasons, and since the function(s) of many ISGs remains unexplored, genome-wide approaches are well placed to investigate what aspects of this response result in an appropriate, virus-specific phenotype. This review discusses the advances screening approaches have provided for the study of host defence mechanisms, including clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9), ISG expression libraries and RNA interference (RNAi) technologies.

中文翻译：

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使用基因筛选发现抗病毒限制因素和途径

病毒感染会激活强大的干扰素 (IFN) 反应，从而诱导数百个 IFN 刺激基因 (ISG) 的表达。这种广泛反应的主要作用是为病毒复制创造不利环境并限制传播；然而，解开这种大规模反应的生物学后果是复杂的。除了看似高度的冗余之外，通常需要结合使用多个 ISG 来限制感染，因为单个 ISG 通常具有低到中等的抗病毒活性。此外，什么 ISG 或 ISG 组合对给定病毒具有抗病毒作用通常是未知的。由于这些原因，并且由于许多 ISG 的功能仍未探索，因此全基因组方法可以很好地研究这种反应的哪些方面会导致适当的病毒特异性表型。