Figure 1.
ChIP-chip and ChIP-seq reveal transcription factor binding genome-wide.
DNA fragments bound by a transcription factor of interest (represented by blue hexagons) are recovered as shown. After mapping each DNA fragment to the genome, the relative frequency of each base within the recovered pool of DNA is summarized as a histogram. An example of such a histogram is shown in blue at the bottom of the figure for the 5′ region of the Drosophila even-skipped (eve) gene containing the enhancers that drive expression in embryonic stripes 2, 3, and 7. The shape of this histogram mimics ChIP-seq data for binding of the Giant transcription factor in D. melanogaster and D. yakuba, as shown in Figure 1A of [19].