MAPK3 and schizophrenia: Total ERK1/2 protein was unchanged between schizophrenia and control (t = 0.817; df = 12; p = 0.097) (Fig. 4e), however phospho-ERK, driven by ERK1, was increased in schizophrenia (t = 2.27; df = 12; p = 0.036) (Fig. 4f and Supplementary Fig. S2).