Figure 6

Combinatorial binding of architectural proteins shapes topological domain structure. Model illustrating the relationship between protein occupancy at APBSs and observed heterogeneity in TAD border strengths. We uncover a spectrum of architectural protein co-localization, ranging from low (blue) to high (red), which scales with the strength of TAD border formation. We propose that differences in TAD border strength reflect the role of architectural proteins in mediating long-range interactions. Interaction frequencies and/or interaction stability are greatest at high occupancy APBSs (red), whereas fewer or less stable interactions at intermediate APBSs (green) allows for inter-TAD interactions, resulting in comparatively weaker TAD borders observed by Hi-C.