CMPK2 and infection: IFN-I treatment suppressed ZIKV replication significantly in NT HFF cells at 24 hours post infection (hpi), but notably there was no decrease in ZIKV titers in IFN-I-treated CMPK2-KO HFF cells, suggesting that CMPK2 is required to facilitate IFN-I-mediated restriction of ZIKV replication (Fig 2F).