Newcastle Disease Virus V Protein Targets Phosphorylated STAT1 to Block IFN-I Signaling.

ABSTRACT: Newcastle disease virus (NDV) V protein is considered as an effector for IFN antagonism, however, the mechanism remains unknown. In this study, the expression of STAT1 and phospho-STAT1 in cells infected with NDV or transfected with V protein-expressing plasmids were analyzed. Our results showed that NDV V protein targets phospho-STAT1 reduction in the cells depends on the stimulation of IFN-?. In addition, a V-deficient genotype VII recombinant NDV strain rZJ1-VS was constructed using reverse genetic technique to confirm the results. The rZJ1-VS lost the ability to reduce phospho-STAT1 and induced higher expression of IFN-responsive genes in infected cells. Furthermore, treatment with an ubiquitin E1 inhibitor PYR-41 demonstrated that phospho-STAT1 reduction was caused by degradation, but not de-phosphorylation. We conclude that NDV V protein targets phospho-STAT1 degradation to block IFN-? signaling, which adds novel knowledge to the strategies used by paramyxoviruses to evade IFN.

SUBMITTER: Qiu X 

PROVIDER: S-EPMC4747598 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature