Furthermore, PKR was not phosphorylated in 293TDPP4 cells duringMERS-ΔNS4a infection, confirming the PKR-independent mechanism of translationalarrest and highlighting differences between cell types in antiviral pathway activation.These differences demonstrate the importance of using multiple model systems to fullyelucidate interactions between viral proteins and host immune pathways. Here, EIF2AK2 is linked to infection.