Fig. 6.
HIF-2 stimulates Flk-1 gene expression. A293 cells were cotransfected with a reporter gene construct containingFlk-1 promoter sequences from −640 bp to +299 bp and with expression vectors encoding the murine HIF-1 or HIF-2 cDNAs, respectively. Relative promoter activities were determined as described in the Materials and Methods section. The promoter activity of the control transfection was arbitrarily set to 1.