?-arrestin 2 as an activator of cGAS-STING signaling and target of viral immune evasion.

ABSTRACT: Virus infection may induce excessive interferon (IFN) responses that can lead to host tissue injury or even death. ?-arrestin 2 regulates multiple cellular events through the G protein-coupled receptor (GPCR) signaling pathways. Here we demonstrate that ?-arrestin 2 also promotes virus-induced production of IFN-? and clearance of viruses in macrophages. ?-arrestin 2 interacts with cyclic GMP-AMP synthase (cGAS) and increases the binding of dsDNA to cGAS to enhance cyclic GMP-AMP (cGAMP) production and the downstream stimulator of interferon genes (STING) and innate immune responses. Mechanistically, deacetylation of ?-arrestin 2 at Lys171 facilitates the activation of the cGAS-STING signaling and the production of IFN-?. In vitro, viral infection induces the degradation of ?-arrestin 2 to facilitate immune evasion, while a ?-blocker, carvedilol, rescues ?-arrestin 2 expression to maintain the antiviral immune response. Our results thus identify a viral immune-evasion pathway via the degradation of ?-arrestin 2, and also hint that carvedilol, approved for treating heart failure, can potentially be repurposed as an antiviral drug candidate.

SUBMITTER: Zhang Y 

PROVIDER: S-EPMC7691508 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature