Extra Spindle Pole Bodies Homolog 1 (ESPL1)

Stable cohesion between sister chromatids before anaphase and their timely separation during anaphase are critical for chromosome inheritance. In vertebrates, sister chromatid cohesion is released in 2 steps via distinct mechanisms. The first step involves phosphorylation of STAG1 or STAG2 in the cohesin complex. The second step involves cleavage of the cohesin subunit SCC1 (RAD21) by ESPL1, or separase, which initiates the final separation of sister chromatids.

Human separin associated with the protein encoded by the pituitary tumor-transforming gene (PTTG1), the human securin homolog, until activation of the APC.it shares 28% identity with Saccharomyces cerevisiae Esp1 and 30% identity with Schizosaccharomyces pombe Cut1. There is no similarity in the N terminus.