Fig. 5. Analysis of the Tcf/Lef binding sites in the EpExt enhancer regions. (A) The sequence of the EpExt enhancer. The Tcf/Lef binding sites are highlighted in red and the Gli binding site in green. The dashed line underlines a non-consensus Tcf/Lef site. Underlined are the EcoRI (-6.6 kb) and BamHI (-6.0 kb) sites that indicate the boundaries of the originally defined Ep Enhancer. Nucleotide positions (in kb) relative to the Myf5 coding sequence are indicated. (B) EMSAs performed with oligonucleotides of the Tcf/Lef binding sites (TBF1-2-3, TBF4 and TBF5), as indicated on the sequence in A, incubated with the reticulocyte lysate alone (RL) or with Lef1 recombinant protein (Lef1), in the presence of a specific antibody (antiHA) and a 100 molar excess of the mutated (mut.) or specific cold (wt) oligonucleotide.