Figure 4. Confirmation of regulated Zap1 ZRE occupancy by chromatin immunoprecipitation.

ZHY6 zap1Δ cells transformed with pZap1^WT were grown to exponential phase in LZM+3 µM or 1000 µM ZnCl₂. Wild-type (DY1457) cells transformed with pYef2 vector were used as a negative control. Cells were then harvested and chromatin immunoprecipitation was performed using primers flanking the ZREs in ZRT1 and ZPS1. Primers specific for the promoter region of CMD1 were used as a negative control. Shown inputs are 1000-fold dilutions of whole cell extracts, and 10-fold serial dilutions of representative samples were also PCR amplified to confirm the quantitative nature of the assay.