Inhibitors, JNK-IN-8 (kindly provided by Nathanael S. Gray, Harvard Medical School, Boston, MA; ref. 24 (link)) and batimastat (cat. no.: SML0041; Sigma-Aldrich; ref. 25 (link)) were added directly from 1 mg/mL stock dissolved in DMSO to larval medium preheated to 55–60°C. Same concentration of DMSO was added to controls without inhibitors. The drugs were incubated with the larvae continuously until harvesting at the third instar stage, equivalent to 7 days.