Cell cycle regulators
Maturation-promoting factor (MPF)
The anaphase-promoting complex/cyclosome (APC/C)
- The APC/C first adds a ubiquitin tag to a protein called securin, sending it for recycling. Securin normally binds to, and inactivates, a protein called separase.
- When securin is sent for recycling, separase becomes active and can do its job. Separase chops up the cohesin that holds sister chromatids together, allowing them to separate.