Separase is a cysteine protease that triggers anaphase in all eukaryotes
by participating in separation of sister chromatids during mitosis. Once
activated, separase hydrolyzes the SCC1 subunit of cohesin, the chromosomal
protein complex responsible for sister chromatid cohesion. Separase and
cohesin are highly conserved from yeasts to humans. When the cell is not
dividing, separase is prevented from cleaving cohesin through its association
with another protein, securin. When anaphase is signaled, the securin is
ubiquitinated and hydrolyzed by APC/cyclosome, releasing the active separase.
Separase is transiently activated between the two meioses and may
also be involved in homolog separation.