The PDZ domain and at lesser extent the DIX domains of Dvl are required for activation of JNK. A) Neurons expressing Dvl full-length or Dvl mutants carrying deletions of the DIX, PDZ or DEP domains were treated with or without the JNK inhibitor SP600125 and MT stability was examined after Nocodazole treatment. B) Quantification shows that neurons expressing ΔDIX or ΔPDZ mutants and treated with SP600125 exhibit the same low level of MT stability as untreated neurons. Conversely, neurons expressing ΔDEP-Dvl mutant and treated with SP600125 show lower level of MT stability than control untreated neurons. C) Full length Dvl and ΔDEP-Dvl bind to MTs along the axon whereas low levels of ΔPDZ-Dvl mutant remains associated to MTs after detergent fixation. Scale bar 15 μm. Three asterisks, P < 0.001.