Figure 3

Posttranslational modification of FOXA2 by PCN reduces its binding to the promoter of MUC5B gene. (A) FOXA2 binding site (underlined) on the MUC5B promoter. (B) Pre-incubation with anti-FOXA2 antibody blocks the binding of FOXA2 to MUC5B promoter, suggesting that the MUC5B-promoter binding is FOXA2-specific. Biotin-labeled probes were incubated alone (Lane 1), or with equal amounts of FOXA2 immunoprecipitated from NCI-H292 cells in presence of indicated amount of anti-FOXA2 antibody (Lanes 2–5) or a 20-fold excess of unlabeled probe (Lane 6). (C) FOXA2 immunoprecipitated from PCN-exposed NCI-H292 cells has reduced ability to bind to the promoter of MUC5B gene. Biotin-labeled probes were incubated alone (Lane 1) or with equal amounts of FOXA2 immunoprecipitated from PCN exposed NCI-H292 cells in the absence (Lanes 2, 4 and 6) or in the presence of a 20-fold excess of unlabeled probe (Lanes 3, 5 and 7).