Regulator of sister chromatid cohesion in mitosis stabilizing cohesin complex association with chromatin. May antagonize the action of WAPL which stimulates cohesin dissociation from chromatin. Cohesion ensures that chromosome partitioning is accurate in both meiotic and mitotic cells and plays an important role in DNA repair. Required for efficient DNA double-stranded break repair. Interacts with the APC/C complex (By similarity). Interacts with the chromatin-bound cohesin complex; the interaction is indirect, occurs after DNA replication and requires acetylation of the cohesin component SMC3. Interacts (via the FGF motif) with PDS5A and PDS5B; the interaction is direct and prevents the interaction of PDS5A with WAPL. Associates with nuclear chromatin from S phase until metaphase and is released in the cytoplasm upon nuclear envelope breakdown. The KEN box is required for the association with the APC/C complex. Phosphorylated. Phosphorylation, as cells enter mitosis, disrupts the interaction with PDS5A and relieves the inhibition of WAPL by CDCA5 (By similarity). Ubiquitinated by the APC/C complex in G1, leading to its degradation. Belongs to the sororin family.