Glucose-stimulated increases in the USF2 promoter activity was mediated by a CRE site located between −1,742 and −1,620 of the USF2 promoter. Quiescent rat mesangial cells were transiently transfected with −1,742 bp USF2 promoter constructs bearing mutations of the HSF, c-Myb, and CRE sites in the presence of normal or high glucose media for 24 h. The plasmid pRL-SV40 was used as internal control. After 24 h, cells were harvested and lysed. The luciferase activity was measured and normalized to Renilla luciferase level. Data are shown with the mean ±SE of triplicates of three separate experiments.