Fig. 2
From: Theoretical principles of transcription factor traffic on folded chromatin
The dual role of looping on transcription factor traffic. a Effect of chromosome conformation on the traffic of transcription factors. At low compaction (left), transcription factors (red) slide uniformly on the chromatin fiber (brown). In the presence of a loop (middle), transcription factors accumulate at the contact point. When the number of loops is high (right), transcription factors diffuse on the outer shell of the globule due to volume exclusion effects. b, c Examples of simulation results with the smallest and largest values of ϕ and ε in cross combinations. For each example, we show the contact matrix of the polymer in log scale, above the traffic of the tracers and the total amount of contacts for each monomer (Row sum). Each plot indicates the values of the Pearson correlation coefficient r between the two, along with their Kullback–Leibler divergence (see text). Panel b shows a simulation with low polymer compaction and high tracer affinity, resulting in a strong correlation between the polymer contacts and the tracer traffic. Panel c shows that the opposite happens with a low tracer affinity and high polymer compaction
