PPARγ binds to PPRE1 in human NHE1 promoter. (A) Schematic representations of full length human NHE1 promoter construct (-1374/+16) and a 5'-deletion construct (-850/+16) with location of PPRE1 and PPRE2 indicated. (B) MCF-7 cells transiently transfected with full length human NHE1 promoter construct (-1374/+16) and a 5'-deletion derivative of the full length lacking the PPRE site (-850/+16). Cells were treated with 3 μM and 5 μM 15 d-PGJ2 for 16 h. CAT-ELISA activity measured following manufacturer's instructions. NHE1 promoter activities were calculated as CAT activity (A405 nm)/μg total protein and expressed as absorbance/μg total protein. Data represents the average +/- SD of two experiments done in duplicate.