EMSA analysis using recombinant PKNOX1 protein and two different labeled ds oligonucleotides (as indicated above): wt probe, which encompasses the Pbx/POU binding site of the FABP7 promoter, and del probe, which contains the same sequence but for the deletion of the Pbx/POU binding site. Lanes 1 and 6, probes with no protein added; lanes 2 and 4, probes plus 10 ng of purified recombinant PKNOX1; lanes 3 and 5, probes plus 1.25 µg of purified recombinant PKNOX1.