Fig. 3.

MAP2K4 reduces MYH9 by downregulating PI3K/AKT/c-Jun-mediated stimulation. (a)Bioinformatics analysis was used to predict the binding sites of c-Jun within promoter of MYH9. (b)(c) QPCR (n = 3 independent experiments, Student's t-test) and Western blot analysis of MYH9 expression in c-Jun-silenced NPC cells and their control cells. (d) Chromatin immunoprecipitation analysis (comparison of all groups vs. IgG group) (n = 3 independent experiments, one-way ANOVA) of c-Jun binding to the MYH9 promoter. (e) The protein-DNA interactions between c-Jun and MYH9 promoter were determined using the electrophoretic mobility shift assay. (f) Luciferase reporter assays (comparison of all groups vs. control group) (n = 3 independent experiments, one-way ANOVA) were performed to confirm c-Jun binding to the MAP2K4 promoter. (g) Protein levels of PI3K, p-PI3K, AKT, p-AKT, c-Jun and MYH9 were measured by western blot in NPC cells treated with MAP2K4 plasmids . (h) Chromatin immunoprecipitation analysis of c-Jun binding to MYH9 promoter in MAP2K4-overexpressed HONE1-EBV⁺ and 5-8F cells. All data are presented as the means ± SD. Experiments were repeated three times. *P < .05. (i) QPCR analysis of MYH9 expression in MAP2K4-transfected HONE1-EBV⁺ and 5-8F cells and their control cells (n = 3 independent experiments, Student's t-test). *P < .05, **P < .01.