PDCoV NS6 and TRIM28

Porcine deltacoronavirus (PDCoV) causes a significant threat to the global swine industry. The PDCoV accessory protein NS6 has the capability to antagonize type I interferon (IFN-I) production and influence viral proliferation. In this study, we discovered that tripartite motif-containing 28 (TRIM28) interacts with NS6 via its RING and coiled-coil (CC) domains, facilitating K48-linked ubiquitination of NS6 at lysine residue K17. This ubiquitination process leads to the degradation of NS6, thereby inhibiting viral replication. Furthermore, NS6 attenuates the expression of interferon-stimulated genes (ISGs). The inhibition of the interferon (IFN) response is further intensified when the degradation of NS6 is inhibited. This study identifies TRIM28 as an antiviral factor that exerts its effects by promoting the degradation of NS6, thereby inhibiting PDCoV replication.