ZNF593 regulates the cGAS-mediated innate immune response by attenuating cGAS-DNA binding.

The enzyme cyclic GMP-AMP synthase (cGAS) is essential for detecting aberrantly located double-stranded DNA (dsDNA) from genomic, mitochondrial, and microbial origins. Through the synthesis of 2'3'-cGAMP, cGAS triggers the activation of the stimulator of interferon genes pathway, which initiates in vivo innate immune responses. Here, we identify zinc finger proteins ZNF593, which translocate from the nucleus to the cytoplasm after viral infection, as a negative regulator of antiviral type I IFN (IFN-I) production. ZNF593 directly binds to cGAS and suppresses its activation by inhibiting the cGAS-dsDNA interaction. ZNF593 deficiency increases IRF3 nuclear translocation and promotes DNA virus-triggered IFN production. Furthermore, ZNF593 deficiency promotes antiviral innate responses in vivo, improving survival rates in mice against HSV-1 infection. We further find that ZNF593 plays a protective role in systemic lupus erythematosus (SLE) pathology. Notably, replenishing ZNF593 effectively reduced IFN production in peripheral blood mononuclear cells (PBMCs) of SLE patients or in the TMPD-induced murine SLE model. Our findings suggest that ZNF593 negatively regulates IFN-β signaling by targeting cGAS activation, providing new insights into the regulatory mechanisms for antiviral defenses and autoimmune diseases.