Fig. 3.
Mutation of the +222/+229 Sp1 binding site in the αENaC gene inhibits promoter activity. The stable mIMCD3 cell lines harboring the pcDNA3.1-Zeo-1.3ENaCα-Luc (WT) or pcDNA3.1-Zeo-1.3ENaCαΔSp1+222/+229-Luc (Δ+222/+229) constructs established in Fig. 2 were assayed for luciferase activities and normalized to cell protein content. The value obtained for WT-transfected cells was set to 1. The values shown are the mean of triplicate determinations or 4 independent experiments. Error bars indicate ± SE. *P < 0.05 vs. WT.