Fig. 7

Functional landscape of principal loops in many-body chromatin interactions. A principal loop is the longest loop (in bp) among chromatin regions forming a many-body (≥3) interaction, where all pairs of bodies (i.e., chromatin regions) forming the interaction are within ≤80 nm Euclidean distance [47]. The pie (a, c) and innermost ring of the sunburst (b, d) plots both show the proportion of specific (bottom) and non-specific (top) principal loops within maximal 3-, 4-, 5-, or ≥6-body interactions; the 2 outer rings(b, d) show the corresponding fraction of principal loops with functional annotations—super-enhancer (SE), enhancer (E), promoter (P)—where gaps represent the fractions of principal loop regions with no known SE, E, or P annotation. Only maximal many-body interactions are represented, i.e., no other chromatin region exists within the interaction distance such that all pairs are within 80 nm. Plots shown are the averages across all 39 modeled genomic loci