Accessibility better explains in vivo occupancy than does intrinsic affinity. We identified and grouped 150-bp local peaks of accessibility within DNaseI accessible regions into non-overlapping cohorts of 200 peaks down the DNase-seq rank list. (a) The median ChIP-chip score in each cohort for each factor. (b) The sum of occurrences of recognition sequences that match the factor's PWM (P < 0.003) in each cohort for each factor. The bottom row in each panel shows the relative DNase-seq scores for each cohort. Data for each factor were normalized by scaling the median value for each row and plotted as a heat map. The correlation coefficients of the data for each factor with the DNase-seq scores are shown on the right. The correlations are calculated using data for each accessible region, not the cohort average values.
Li et al. Genome Biology 2011 12:R34 doi:10.1186/gb-2011-12-4-r34