DNA virus infection activates DNA-PK, which phosphorylates PARP1 to facilitate its cytoplasmic translocation and inhibit antiviral immunity by directly PARylating cGAS.
Virus infection modulates both host immunity and host genomic stability. Poly(ADP-ribose) polymerase 1 (PARP1) is a key nuclear sensor of DNA damage, which maintains genomic integrity, and the successful application of PARP1 inhibitors for clinical anti-cancer therapy has lasted for decades. However, precisely how PARP1 gains access to cytoplasm and regulates antiviral immunity remains unknown. Here, we report that DNA virus induces a reactive nitrogen species (RNS)-dependent DNA damage and activates DNA-dependent protein kinase (DNA-PK). Activated DNA-PK phosphorylates PARP1 on Thr 594 , thus facilitating the cytoplasmic translocation of PARP1 to inhibit the antiviral immunity both in vitro and in vivo . Mechanistically, cytoplasmic PARP1 interacts with and directly PARylates cyclic GMP-AMP synthase (cGAS) on Asp 191 to inhibit its DNA-binding ability. Together, our findings uncover an essential role of PARP1 in linking virus-induced genome instability with inhibition of host immunity, which is of relevance to cancer, autoinflammation, and other diseases.
Wang et al. (Fri,) conducted a other in Virus infection. DNA virus infection was evaluated on Cytoplasmic translocation of PARP1 and PARylation of cGAS. DNA virus infection activates DNA-PK, which phosphorylates PARP1 to facilitate its cytoplasmic translocation and inhibit antiviral immunity by directly PARylating cGAS.