Intriguingly and in contrast to HCV, PYM1, along with MAGOH and UPF1, was identified as an anti-viral factor of WNV, DENV and ZIKV (who are from a different Flaviviridae genus than HCV) because knockdown of PYM1 increased viral infection and/or RNA levels in HEKs cells [183]. Here, UPF1 is linked to viral infectious disease.