The MPF Protein Complex Turns Itself Off By

Question

The MPF protein complex turns itself off by
A)activating a process that destroys cyclin components.
B)activating an enzyme that stimulates cyclin.
C)binding to chromatin.
D)exiting the cell.
E)activating the anaphase-promoting complex.

Accepted Answer

The MPF protein complex is responsible for initiating and regulating the events of mitosis. Once these events are complete, the MPF complex needs to be turned off to prevent the cell from continuing to divide uncontrollably. The MPF complex accomplishes this through a negative feedback loop: it activates a process that destroys cyclin components. Cyclin is an important component of the MPF complex, and without it, the complex cannot function properly. By destroying cyclin, the MPF complex essentially turns itself off, allowing the cell to exit mitosis and proceed with normal cellular activities.