Figure 8. Pdip1 binds to sequences overlapping with the B-Myb transactivation domain. (A). Schematic illustration of GST- and YFP-B-Myb constructs. (B). GST-pull down experiments were performed with the indicated GST and GST-B-Myb fusion proteins and lysates of QT6 cells expressing Myc-Pdip1. Bound proteins (lanes 2 to 4) and an aliquot (10%) of the input sample (lane 1) were analyzed by western blotting using a Myc-specific antibody. An anti-GST western blot of the bacterial proteins used in the pull-down experiment is shown in the lower panel and demonstrates comparable protein amounts. (C). QT6 cells were transfected with the indicated combinations of plasmids encoding Myc-Pdip1, YFP-B-Myb, YFP-B-Myb D3 (345–440) and YFP. Cells were lysed 24 h post-transfection and the soluble fraction was incubated with GFP-trap beads, resulting in the binding of YFP-fusion proteins and their binding partners to the beads. Bound proteins and aliquots (6%) of the input extracts were analyzed by western blotting with antibodies against Myc and GFP.