CREB and zif268 binding sites show strong location specificity. All histograms were created using a bin size of 50 bp. The total number of binding sites in each 50 bp region was divided by the total number of promoters for that dataset. Shown are both human (red) and mouse (blue) and promoters. For the intergenic dataset, the area shown is from -51,200 bp to -50,000 bp relative to transcription start. The mouse dataset is the location of mouse binding sites when the homologous gene also has a binding site of the same type. The human dataset is the location of human binding sites when the homologous gene also has a binding site of the same type. A) Promoters with a CREB binding site are grouped by position relative to transcription start, showing pronounced location specificity within the promoter. (B) The same as (A) but for zif268. (C) The same as (A) but for the conserved CREB targets in the mouse-human homogene dataset. (D) The same as (A) but for the conserved zif268 targets in the mouse-human homogene dataset. The percentage of promoters with a binding site is calculated relative to the total number of homologous pairs.