MDM2 and infection: Additionally, based on the Huang et al. (58) study, TGEV incorporation can obviously lower both p300/CBP and MDM2 levels and simultaneously upregulate p53 levels by phosphorylating serine residues at positions 15, 20, and 46 of p53, in addition to transiently activating the p38-MAPK pathway to mediate apoptosis during early infection.