Gli1 and Gli2 repress the activity of the mouse Ano1 promoter. A) Schematic of the mouse Ano1 promoter. Core promoter elements and putative binding sites for transcription factors identified in the human ANO1 promoter are indicated in black. In blue are the putative Gli binding sites. InR, initiator region. B) Expression of the 1.8 Kb region upstream of the exon 1 of mouse Ano1 in promoter-luciferase chimeric constructs in the HEK293 cell line. The promoter activity is significantly higher than empty vector (8.5 ± 0.6–fold increase), and it is significantly up-regulated after treatment with 10 µM concentration of IL4 for 48 h (17.9 ± 2.1–fold increase over untreated cells). Ctrl, control. Data are expressed as mean ± sd of 6 independent experiments. *P < 0.05, 2-way ANOVA with Sidak’s multiple comparison test. C) Expression of the mouse Ano1 promoter-luciferase chimeric constructs in the HEK293 cell line. Promoter activity was calculated as fold increase over the luciferase activity of the empty vector. The activity of the mouse Ano1 promoter was significantly repressed in cells cotransfected with Gli1 (0.41 ± 0.2) and Gli2 (0.29 ± 0.14) expression vectors (n = 6). *P < 0.05, 1-way ANOVA with Dunn’s multiple comparisons test.