To examine effects of very early PKR signaling on PVSRIPO, we used staggered inhibition with C16 in A375 cells (0.3 μM; see Fig. S5 for dose optimization of C16, IKK16, and Bx795), starting with addition to PVSRIPO infection medium at the 0-h time point (Fig. 6B). Here, EIF2AK2 is linked to infection.