WT1 (–Ex5/–KTS) binds to the A1 promoter. Chromatin immunoprecipitation assays were performed as described using 32DV4 and 32DWT1 cells treated overnight with 50 μM ZnCl₂. The arrow indicates the position of the PCR product representing the A1 promoter, present in the 32DWT1 sample but not in the 32DV4 sample. Lane 1 is the control with no template, lanes 2 and 5 are the no-antibody controls from 32DV4 and 32DWT1 cells, respectively, and lanes 3 and 4 are the samples from 32DV4 cells (Lane 3) and 32DWT1 cells (Lane 4). The identity of the PCR fragment was confirmed by sequencing.