Figure 4

HOXA7 and PBX2 bind as a heterodimer to the Pbx sequence, but not to EMX2. EMSA analysis was performed with ³²P-labeled oligonucleotides containing the (A) Pbx consensus sequence and (B) EMX2 consensus sequence. Supershift assays were also performed with antibodies to HOXA7 and PBX2. Lanes are designated as follows: lane 1, negative control using excess unlabeled cold probe (100×) with nuclear extract; lane 2, ³²P-labeled probe without nuclear extract, showing the migration of free probe in absence of nuclear extract; lane 3, ³²P-labeled probe with nuclear extract; lane 4, supershift reaction with ³²P-labeled probe, nuclear extract and anti-PBX2 antibody; lane 5, supershift reaction with ³²P-labeled probe, nuclear extract and anti-HOXA7 antibody; lane 6, supershift reaction with ³²P-labeled probe, nuclear extract, anti-Pbx2 and anti-HOXA7 antibodies; lane 7, ³²P-labeled probe without nuclear extract but with anti-PBX2 and anti-HOXA7 antibodies. Abbreviation: n.s., non-specific complex.