a, Hi-C heatmap at 10kb resolution for rad21-K1. b, 4C-like profiles showing the average contact probabilities of centromeres and telomeres WT, wild type. c, Distribution of intra-arm, inter-arm and inter-chromosomal contact frequencies. d, Hi-C heatmaps of a segment of chromosome 2 overlaid with blue lines corresponding to cohesin (Psc3) peaks from the 10kb binned profile (top); Hi-C directional preference profile (below). To compare results from different experiments, color scales were chosen such that the maximum value corresponds to the ninety-ninth percentile of intra-arm contact frequencies. The boundaries detected in rad21-K1 may result from random fluctuations in directionality due to experimental limitations, or remaining cooperative factors required for boundary establishment. e, Relative contact probability around a cohesin peak as a function of insulation distance averaged over all cohesin peaks (insulation plot). Depletion of contact probability (blue stripe) is not observed in rad21-K1.