Fig. 1

Pericentromeric heterochromatin is organized into domains a schematic of Drosophila melanogaster chromosomes showing the pericentromeric regions (light blue) included in the 5C experiment. The centromere is in green and the euchromatic regions in dark blue. b Schematic representation of 5C primer design by alternating primer design scheme, at the adjacent restriction enzyme sites. Forward (with T7 overhang) and reverse (with T3 overhang) primers are used to amplify the interacting DNA junctions from the 3C library. c A pairwise interaction map of Chr2L showing the mapped active Het TADs green and inactive Het TADs in red, respectively, along with the epigenetic marks of H3K9me3, HP1a, H3K4me3 and H3K36me3. Active genes in the pericentromeres are enriched for H3K9me3 along with active histone modifications. MARs are indicated by red bars. TAD boundaries (grey bars) partition distinct epigenomic domains