AML1-ETO does not change the DNA binding of PU.1.
The PU.1-binding sequence from the CD11b promoter was chosen and labeled with γ32p-dATP (lane 1), incubated with in vitro–translated PU.1 (lane 2), or in vitro–translated PU.1 and anti-PU.1 antibody (lane 3). As a competitor, unlabeled probe was used in 100 molar excess with (lane 5) and without (lane 4) anti-PU.1 antibody. To investigate if this binding and supershift is specific for PU.1, similar experiments were performed with rabbit reticulocyte lysate (lanes 6-9). In presence of AML1-ETO, PU.1 still binds to its DNA (lane 10) and supershifts with anti-PU.1 antibody (lane 11). In presence of AML 4-ETO and competitor probe alone (lane 12) or plus anti-PU.1 antibody (lane 13), no binding of PU.1 was observed. To the left of blots, ss indicates supershift; s, shift.
