Inhibition of cGAS-Mediated Interferon Response Facilitates Transgene Expression

• Published in: iScience 2020-04, Vol.23 (4), p.101026-101026, Article 101026
• Main Authors: Fu, Yajuan, Fang, Yijun, Lin, Zhang, Yang, Lei, Zheng, Liqun, Hu, Hao, Yu, Tingting, Huang, Baoting, Chen, Suxing, Wang, Hanze, Xu, Shan, Bao, Wei, Chen, Qi, Sun, Lijun
• Format: Article
• Language: English
• Subjects: Biological Sciences; Molecular Biology; Molecular Mechanism of Gene Regulation
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2020.101026

DNA transfection is often the bottleneck of research and gene therapy practices. To explore the mechanism regulating transgene expression, we investigated the role of the cGAS-STING signaling pathway, which induces type-I interferons in response to DNA. We confirmed that deletion of cGAS enhances transgene expression at the protein level by ~2- to 3-fold. This enhancement is inversely correlated with the expression of interferons and interferon stimulated genes (ISGs), which suppress expression of transfected genes at the mRNA level. Mechanistically, DNA transfection activates the cGAS-STING pathway and induces the expression of the OAS family proteins, leading to the activation of RNaseL and degradation of mRNA derived from transgenes. Administration of chemical inhibitors that block cGAS-mediated signaling cascades improves the expression of transgenes by ~1.5- to 3-fold in multiple cell lines and primary cells, including T cells. These data suggest that targeting the cGAS-STING pathway can improve transgene expression, and this strategy may be applied to gene therapy. [Display omitted] •cGAS-STING pathway suppresses transgene expression from DNA vectors•Interferon-mediated mobilization of OAS-RNaseL system degrades plasmid-derived mRNA•Inhibitors of cGAS-STING-IFN-ISG axis enhance gene expression in primary cells Biological Sciences; Molecular Biology; Molecular Mechanism of Gene Regulation