Figure 3.

Identification of transcription factor binding to the E-box motifs of the proximal hTERT promoter. Nuclear extracts from F9 cells, hES cells, and HL-60 cells, before and after differentiation, were incubated with ³²P-labeled oligonucleotide corresponding to position −177 to −146 (oligo-1) (A) or with ³²P-labeled oligonucleotide corresponding to position 32–58 (oligo-2) (B) of the hTERT promoter that includes the E-box motif. Incubation was performed without or with competitor (150-fold excess of cold oligonucleotide) or with antibodies, as indicated above each lane. As a control, nuclear extracts from NHF and MEF cells were used. Arrowheads indicate specific retarded bands.