Final answer:
The regulatory component of MPF is called cyclin, which is essential for the activation of MPF and proper progression of the cell cycle through to mitosis.
Step-by-step explanation:
The regulatory component of MPF (Maturation Promoting Factor or Mitosis Promoting Factor) is called cyclin, which has a stimulatory effect on MPF activity and plays a vital part in regulating interactions with its substrates. Cyclin binds to cyclin-dependent kinase (cdk) to form the active kinase required for cell cycle progression, particularly the transition from the G2 phase to mitosis. The concentrations of cyclin increase throughout the cell cycle, peaking during M phase, while cdk levels remain relatively constant. The Nobel Prize in Physiology or Medicine in 2001 was awarded to Leland H. Hartwell, R. Timothy Hunt, and Paul M. Nurse for their discovery of MPF and its components. MPF's activity is crucial for the cell's progression through the cell cycle, indicating when a cell should enter mitosis.