Both ERK1/2 and JNK MAPKs were activated rapidly after HSV1 infection, as evidenced by their phosphorylation in HT1080 cells (Fig 4A) as well as in NB41A3 cells (S2F Fig) and virus infection activated c-Jun and c-Fos required for AP-1 activation (S2E Fig). Here, MAPK3 is linked to viral infectious disease.