Figure 1.

MAP kinase activation by treatment with E-FOL or voltage. Suspension cultures were treated with 100 μg mL⁻¹ E-FOL (A and B) or 60 V (E and F) at time point 0. Samples were taken at the indicated time points and analyzed by in-gel kinase assay with MBP as substrate. B and F, Cells were pretreated with cycloheximide (CHX) or α-amanitin (αAM) 15 min before stimulation. C and G, Cells treated with the indicated concentrations of E-FOL (C) and voltage (G) were collected 5 min after stimulation and analyzed by in-gel kinase assay. D and H, Immunoprecipitation with phospho-Tyr-specific antibody 4G10. Crude extract of E-FOL- (D) or voltage- (H) treated cells was used for immunoprecipitation without competitor (−) or in the presence of 1 mm phospho-Tyr (PY), phospho-Ser (PS), or phospho-Thr (PT). The precipitate was analyzed by in-gel kinase assay.