OAS1 and infection: Importantly, further evidence that OAS1 protein is expressed is that the OAS1 gene is intact (Fig. 1), the mRNA is clearly expressed and induced by IFN or infection (Fig. 2) and contains an ORF encoding a protein very similar to human OAS1 with predicted active site intact (Fig. 3; Table 1), and OAS1-KO cells have increased SINV replication (Fig. 6).