(Science: enzyme) A protein kinase that drives both the mitotic and meiotic cycles in all eukaryotic organisms.
In meiosis it induces immature oocytes to undergo meiotic maturation. In mitosis it has a role in the G2/M phase transition. Once activated by cyclins, maturation-promoting factor directly phosphorylates some of the proteins involved in nuclear envelope breakdown, chromosome condensation, spindle assembly, and the degradation of cyclins.
The catalytic subunit of maturation-promoting factor is protein p34cdc2.