Fig. 2

Downregulation of CFTR expression during hypoxia is HIF-1 dependent and relies on both the 5′ and 3′ UTRs of CFTR mRNA. a Calu3, 16HBE14o- and HeLa WT CFTR cells were treated with hypoxia mimetics (500 μM DMOG for 12 h (light grey) and 200 μM CoCl₂ for 12 h (dark grey)) and the mRNA levels were monitored in qRT-PCR experiments. CFTR mRNA levels from 2 independent experiments (n = 8) are plotted relative to 18S rRNA levels and expressed as a fold change over the untreated control. b Calu3 cells were transfected with 5′UTR CFTR luciferase reporter (white), 3′UTR CFTR luciferase reporter (light grey) and co-transfected with both 5′UTR and 3′UTR CFTR luciferase reporters (dark grey) and treated with hypoxia mimetics (500 μM DMOG or 200 μM CoCl₂ for 12 h) and the luciferase activity was monitored. These reporters were normalized to internal controls (Renilla) firefly luciferase activities from 2 independent experiments (n = 6) and plotted and expressed as a fold-change over non-treated control. Error bars represent standard deviations. Significant changes (P < 0.05) are marked with an asterisk