Fig. 2: Cohesin^COH-1 creates fountains at active enhancers.

a Fluorescence signal in the head of third larval stage control animals expressing SMC-1::GFP without TEV expression. The light patch in each nucleus corresponds to the nucleolus. Strains in which TEV cut sites have been inserted in either of the two alternative cohesin kleisins COH-1 and SCC-1 are shown. b (top left) Average COH-1 ChIP-seq profiles in young adult animals at active (red) or repressed (green) enhancers and H3K27me3-enriched regions (blue). (bottom left) Heatmap of COH-1 enrichment on active enhancer regions, sorted by COH-1 ChIP-seq enrichment. (left) Average contact frequency maps centered on enhancers segmented according to COH-1 ChIP-seq abundance. c SMC-1::GFP signal as in a upon cleavage of COH-1 and SCC-1. d Cleavage of cohesin^COH-1 but not cohesin^SCC-1 leads to disappearance of active enhancer fountains. Average contact frequency maps, centered on active enhancers upon cleavage of COH-1 and/or SCC-1. The difference between the kleisin cleavages and TEV control is shown on the right with a green/magenta color scale. e Contact frequency map in TEV control animals (top) and upon cohesin^COH-1 cleavage (bottom) in a section of chromosome IV. f (top) Ratio contact frequency map between cohesin^COH-1 cleavage and TEV control, highlighting the disappearance of the fountains (blue, negative values). (bottom) Tracks showing detected fountains, active enhancers (Daugherty et al.⁷: D; or Jaenes et al.⁶: J), chromatin domains²³ and location of genes (bottom). g Autosomal chromatin state coverage of detected fountain bins (left) and their adjacent bins, sorted by distance to the detected fountains. Autosome-wide coverage is shown on the right side. Chromatin states from ref.²³. h Average contact frequency maps centered on detected fountains for all fountains and for top, middle and bottom asymmetry quintiles of all fountains, based on the asymmetry score described in the methods section.