Separase Protease Activity is Required for Cytokinesis in addition to Chromosome Segregation

Chromosomal segregation and cytokinesis are tightly regulated processes required for successful cell division. The cysteine protease separase cleaves a subunit of the cohesin complex to allow chromosome segregation at anaphase onset. Separase also regulates meiotic cortical granule exocytosis and vesicle trafficking during cytokinesis, both of which involve RAB-11. Separase has non-proteolytic signaling functions in addition to its role in substrate cleavage, and its mechanism in exocytosis is unknown. We sought to determine whether separase regulates RAB-11 vesicle exocytosis through a proteolytic or non-proteolytic mechanism. To address this question, we generated a protease-dead separase,