We next sought to evaluate the contribution of JNK to upd3 induction upon infection with Ecc15. We first verified whether Ecc15 infection triggers JNK activation in ECs, via co-immunostaining of the phosphorylated form of JNK and an EC marker (Myo-Gal4TS>UAS-GFP) (S8A Fig). Here, MAPK8 is linked to infection.