MAPK activation in BmN cells infected with vfgf-deficient BmNPV. BmN cells were infected with BmNPV T3 (A) or BmFDFD (B), a BmNPV mutant lacking functional vfgf, at an MOI of 5. Activation of ERK and JNK at 0, 4, 8, 12, and 24 hpi was assessed by Western blotting using phospho-ERK (pERK)- and phospho-JNK (pJNK)-specific antibodies, respectively. Similar results were obtained in two independent experiments.