The Glycosyltransferase ST3GAL2 Modulate the Proliferation and Inflammation Response in PRRSV Infection 

Abstract The viral proliferation process of envelop viruses including invasion, assembly, and release process is impacted by glycosylation. Sialic acid modification mainly exists in the terminal glycosylation of proteins and lipids. In this study, the effect of porcine sialylglycosyltransferase (ST3GAL2) on virus proliferation, as well as regulation of inflammatory factor in PRRSV-infected 3D4/21 cell model were analyzed. The expression of ST3GAL2 was up-regulated in PRRSV-infected 3D4/21 cells. The expression of ST3GAL2 that promote the proliferation of PRRSV was determined by overexpression and interference experiment. The ST3GAL2 localizes to Golgi apparatus and interacts with PRRSV structural protein GP2a was verified by confocal microscopy and co-immnoprecipitation array, which may play roles in the assembly of PRRSV envelope and virus proliferation. The expression of ST3GAL2 also impacts the expression of inflammatory cytokines, which regulate cellular immunity and promote the immune escape of PRRSV from innate immunity. Our results highlighted a potential mechanism whereby ST3GAL2 promotes PRRSV proliferation and offers the anti-inflammatory role of ST3GAL2 in cellular immunity.