Mouse oligoadenylate synthetase 1b inhibits West Nile virus replication by acting through the stem-loop 2 in the 3′-untranslated region

抄録

Oligoadenylate synthetase (OAS) plays a role in intracellular viral defense. Mouse Oas1b is responsible for the susceptibility to flaviviruses. The flavivirus replication inhibitory effect of Oas1b is independent of its enzymatic activity; however, its mechanism remains unclear, though mouse Oas1b possibly targets the 3′-stem-loops (SLs). We measured the effect of Oas1b by removing and overexpressing SLs in the 3′-untranslated regions (UTRs) of the West Nile virus (WNV) replicon. Both SL2 deletion and SL2 RNA overexpression in the 3′-UTR of the WNV replicon resulted in the loss of Oas1b-mediated replication inhibition. These results revealed that WNV SL2 is essential for Oas1b-mediated replication inhibition.