Figure 6. 4D reorganization of the yeast genome.. (B) Illustration of the three chromatin folding states characteristic of each of the cell cycle phase. Establishment of sister-chromatid (SC) cohesion during S phase increases intra-SC long-range contacts and leads to the individualization of the replicated chromosomes. Then during M phase, the two sisters are segregated and each chromatid (C) individualized thanks to the action combination of cohesin cleavage, condensin loading and spindle elongation. The chromosomes display a stretched internal structure, which relaxed upon destabilization of the spindle with nocodazole. 