Compound 7 modulates specifically levels of phospho-SAPK/JNK. Shown are representative results from western blotting experiments. Fifty embryos at 24 hpf were cultured for 5 h either in vehicle (DMSO, indicated by lanes marked D) or in 100 µm compound 7 (indicated by lanes marked 7). Embryos were then deyolked and dissociated directly into SDS sample buffer (4 µL per embryo). Each lane contains a lysate representing 5 embryo equivalents. Samples were electrophoresed in a 10% SDS-PAGE-Tris gel (Invitrogen, Carlsbad, CA, USA), transferred to nylon and probed using primary antibodies (Cell Signaling Technology, Danvers, MA, USA) specific to the phosphorylated (active) isoforms for each protein. After incubation with appropriate secondary antibodies, filters were developed using ECL (Santa Cruz, Santa Cruz, CA, USA) and exposed to film. An equivalent set of samples was stained directly from the gel using Coomasie Blue (CB), demonstrating equal protein loading. Antibodies used are indicated next to each panel. Note that only p-SAPK/JNK levels are changed, being increased substantially by exposure of embryos to compound 7. Equivalent results were reproduced with independent experiments.