The activation of the OAS1 gene occurs through double-stranded RNA (dsRNA). This does not normally occur in a cell. The encoded 2',5'-oligoadenylate synthetase1 is induced by interferons and now generates 2'-5'-linked oligoadenylates from ATP molecules (Koul A et al. 2020). These molecules activate latent RNase L, which causes degradation of both viral and endogenous RNA and inhibition of viral replication. OAS1 continues to play an important role in apoptosis induction.
The 2'-5'-oligoadenylate synthetase1 is a hugely important sensor for cytosolic double-stranded RNA (dsRNA), and thus plays a crucial role in limiting viral infections. Activation of the latent ribonuclease (RNase L) halts viral replication and establishes an antiviral state. The importance of the OAS/RNase L pathway is demonstrated by the fact that different viruses have evolved numerous different strategies to circumvent the effects of OAS activation. How OAS synthetases are regulated by viral or cellular RNAs is not yet fully understood (Schwartz SL et al. 2019).