Luciferase reporter studies on ALOX12 promoter in PMA-treated HEL cells. (A) Schema showing 5′ upstream region of ALOX12 gene with 4 RUNX1 consensus sites. (B) Effect of 5′ sequential truncation of ALOX12 promoter region on expression of luciferase reporter in untreated (■) and PMA-treated (□) HEL cells. Fold increase in luciferase activity was measured as ratio of control vector to luciferase vectors carrying various lengths of promoter and normalized to Renilla luciferase constructs. Data are mean ± SEM of 3 experiments. (C) Effect of disruption of individual RUNX1 sites on ALOX12 expression. Each RUNX1 site was disrupted sequentially by introducing point mutations (□ boxes) in RUNX1-binding sites. Data are mean of 3 experiments.