Regulator of sister chromatid cohesion in mitosis which may stabilize cohesin complex association with chromatin. May couple sister chromatid cohesion during mitosis to DNA replication. Cohesion ensures that chromosome partitioning is accurate in both meiotic and mitotic cells and plays an important role in DNA repair. Plays a role in androgen-induced proliferative arrest in prostate cells (By similarity). Interacts with the cohesin complex. Interacts with RAD21; the interaction is direct. Interacts with WAPL (via FGF motifs) or CDCA5 (via the FGF motif); the interaction is direct, cohesin-dependent and competitive (By similarity). Expressed in prostate. Belongs to the PDS5 family.