Fig. 3. ERα binds to the degenerated ERE in the hTERT promoter. A, schematic diagram of hTERT promoter. The first base of the hTERT promoter is labeled as −1. The sequences of an imperfect palindromic ERE at −2677 and a Sp1/ER site at −873 are shown. B, recombinant ERα proteins were incubated with 32P-labeled probes containing a degenerated ERE at −2677 in the presence or absence of unlabeled competitors. Arrow A, specific binding complex; arrow B, supersifted complex; arrow F, free probe; homo, homologous competitors; homo MT, homologous competitors with mutations; ERE, consensus ERE in Xenopus vitellogenin A2 promoter; Myc, c-Myc consensus motif.