Cleavable component of the cohesin complex involved in chromosome cohesion during cell cycle. The cohesin complex is required for the cohesion of sister chromatids after DNA replication. The cohesin complex apparently forms a large proteinaceous ring within which sister chromatids can be trapped. At metaphase-anaphase transition; this protein is cleaved by ESP1 and dissociates from chromatin; allowing sister chromatids to segregate. {ECO:0000269|PubMed:10403247; ECO:0000269|PubMed:9335333; ECO:0000269|PubMed:9335334; ECO:0000269|PubMed:9491073}.