ERN1 and infection: Compared with control KD with mock infection, RSV induction of GFPT2 mRNA in control KD cells was 63 ± 5.2-fold (P = 5.17E-11), whereas that in XBP1 and IRE1α KD cells were downregulated to 18.3 ± 1.64-fold (P = 2.04E-09) and 34.6 ± 2.71-fold (P = 3.22E-07), respectively; the relative basal level of GFPT2 was also downregulated dramatically by knock-down of XBP1 (0.12 ± 0.01-fold, P = 5.03E-08) and significantly by knockdown of IRE1α (0.64 ± 0.039-fold, P = 1.69E-04).