FIG. 2.

PAX4 binding to islet gene promoters. (A) EMSA using truncated (PAX4-T) and full-length (PAX4-FL) PAX4 to bind to hormone gene regulatory elements. ³²P-end-labeled oligonucleotides (10,000 cpm) were incubated with 1 μl of a 50-μl IVTT reaction in each lane and then electrophoresed. (B) EMSA using PAX4-T to bind to ³²P-end-labeled rInsIC2 probe (10,000 cpm). A 50- to 100-fold molar excess of unlabeled competitor oligonucleotides was added to the lanes indicated; 0.05 μl of a 50-μl IVTT reaction was used in each lane. (C) EMSA comparing the binding of PAX4-T and PAX6 to ³²P-end-labeled hormone gene regulatory elements; 0.1 μl of a 50-μl IVTT reaction was used in each lane. The open arrowhead (>) points to a weak PAX4-T–GluG1 complex.