Regulation of mouse hepcidin genes by USF1/USF2. (A) Approximately 600 bp of mhepc1 (mhepc1P-luc) and mhepc2 (mhepc2P-luc) promoters were cloned from the SWR mouse strain into pGL3Basic; BHK cells were cotransfected with 100 ng of each construct and with either USF1 or USF2 to determine transactivation. (B) Various concentrations of A-USF or (C) USF2ΔB were cotransfected into BHK cells with mhepc1P-luc or mhepc2P-luc together with 100 ng USF1 or USF2 plasmids to determine transcriptional repression. Data are representative of 2 independent assays (means ± SEM). *P < .05; **P < .005; ***P < .001 (determined by 1-way ANOVA/Student-Newman-Keuls comparisons test).