a) FACS for DNA content (left) and Western blotting (right) showing that cdc45 and cd45 scc1-73 cells enter mitosis without DNA replication, with CDK phosphorylating condensin on Smc4 Serine 4 (Smc4 S4P) with the same kinetics as wildtype cells ( unspecific band). Picture of Ponceau stained blot confirms equal loading of Western (right, bottom). Western blotting for to confirm CDK activation in cells was from one experiment. ( ∗ b) Plot of nuclear morphology examining number of DAPI stained cells from the indicated timepoints that have undergone nuclear division. % of single nucleus (rectangles), double nuclei (checked line with squares) and cells with an anaphase nucleus are shown (grey line). ( c) (Top) Zoom into contact heatmaps from cdc45 mitotically arrested cells, C, (top) and cohesin depleted mitotically arrested cells, CH, (bottom), for selected regions on (left) ChrXV (0-330 kb (CENXV is at 330 kb)) and (right) the post-rDNA region of ChrXII (660 kb to 940 kb). ( d) Zoom into log 2 ratio of CH over C contact maps for selected regions on (left) ChrXV (0-330 kb (CENXV is at 330 kb)) and (right) the post-rDNA region of ChrXII (660 kb to 940 kb). Arrows indicate a prominent track of cohesin-dependent contacts seen also in Supplementary Fig. 3a). All contact maps shown were assembled from two independent experiments.