Given that oxidative stress responses have been shown to mediate antiviral innate immune responses to DENV (43) and that activation of the unfolded protein response is required for productive infection (44, 45), it is likely that the anomalous phenotype exhibited by YBX1 KO MEFs is per se conducive to DENV infection and thus, the proviral function of YBX1 was masked in these cells. This evidence concerns the gene YBX1 and infection.