p120-catenin promotes innate antiviral immunity through stabilizing TBK1-IRF3 complex.

TBK1-IRF3 complex plays vital roles in antiviral immune responses, its regulatory mechanisms are currently incompletely understood. p120-catenin (p120), an armadillo-repeat protein, mainly regulates the stability of classical cadherins and the development of epithelial-to-mesenchymal transitions (EMTs). Here we report that p120 is a positive regulator of type I IFN production. Ectopic expression of p120 enhanced Vesicular stomatitis virus and Sendai-virus-induced type I IFN production, whereas knockdown of p120 expression suppressed type I IFN production. Mechanistically, p120 promoted phosphorylation of IRF3 via stabilizing the TBK1-IRF3 complex. Consistently, p120 knock down mice are more susceptible to VSV infection as indicated by higher tissue viral titers, less IFN-I production and greater infiltration of immune cells. This study reveals p120 as an important positive regulator in innate immunity and identifies that p120 facilitates host antiviral response through stabilizing TBK1-IRF3 complex.