FIG. 6.

Analysis of HIF-1 interaction with the mutated HREs in the hTERT promoter. (a and b) ³²P end-labeled TERT/HREmt1 or ³²P end-labeled TERT/HREmt2 oligonucleotide was used as a probe. For the competition assays, a 200-fold molar excess of the HRE was used. For the supershift assay, anti-HIF-1α antibody (0.5 μg) was added to the binding reaction. (c) The HIF-1 consensus oligonucleotide was end labeled with ³²P. For the competition assays, 200-fold molar excesses of TERT/HRE1, TERT/HRE2, TERT/HREmt1, TERT/HREmt2, and HRE were added to the binding reactions. For the supershift assay, anti-HIF-1α antibody (0.5 μg) was added to the binding reaction. The thick arrow indicates HIF-1/DNA complexes, and thin arrows indicate supershifted bands. NS, nonspecific.