FIG. 6.
CBFα2 binds the human IgH μ enhancer in vitro. (A) EMSAs were carried out with bacterially expressed and purified CBFα241-190, which contains the DNA binding Runt domain of CBFα2, and hWT and mutant enhancer probes as indicated. Specific nucleoprotein complexes in lanes 1, 2, 5, and 6 are indicated by an arrow. (B) In vitro competition assays with CBFα241-190 bound to the human WT probe. EMSAs were carried out as described in the text, with 25-, 125-, and 250-fold molar excesses of competitor DNA fragments indicated by triangles. Competitor DNA was excised as dimeric fragments from reporter plasmids used for transfections in Fig. 4C and contain wild-type or mutated human enhancer sequences as indicated.