Frequency of transcription factor binding sites (TFBS), to regulated transcription factors (TFs). The TFBS were located within 2000 bp or 500 bp DNA sequence upstream of the ATG of genes regulated by zinc supplementation at different time-points. Panel A represents the % genes regulated at each time point contain TFBS for ppara (circles and solid line), nra61a (gcnf) (circle and dashed line) and mtf1 (triangle and dashed line). Panel B shows the % regulated genes containing stat1 (circles and solid line) and gata3 (triangle and dashed line) binding sites. A significant difference in frequency of occurrence of the respective TFBS, relative to that in a cohort of 198 stable (< 1.8-fold change) genes is indicated by an asterisk (P < 0.05, z-test).