The schedule of destruction of three mitotic cyclins can dictate the timing of events during exit from mitosis

  • Parry D
  • O'Farrell P
  • 28


    Mendeley users who have this article in their library.
  • 115


    Citations of this article.


Background: Degradation of the mitotic cyclins is a hallmark of the exit from mitosis. Induction of stable versions of each of the three mitotic cyclins of Drosophila, cyclins A, B, and B3, arrests mitosis with different phenotypes. We tested a recent proposal that the destruction of the different cyclins guides progress through mitosis. Results: Real-time imaging revealed that arrest phenotypes differ because each stable cyclin affects specific mitotic events differently. Stable cyclin A prolonged or blocked chromosome disjunction, leading to metaphase arrest. Stable cyclin B allowed the transition to anaphase, but anaphase A chromosome movements were slowed, anaphase B spindle elongation did not occur, and the monooriented disjoined chromosomes began to oscillate between the spindle poles. Stable cyclin B3 prevented normal spindle maturation and blocked major mitotic exit events such as chromosome decondensation but nonetheless allowed chromosome disjunction, anaphase B, and formation of a cytokinetic furrow, which split the spindle. Conclusions: We conclude that degradation of distinct mitotic cyclins is required to transit specific steps of mitosis: Cyclin A degradation facilitates chromosome disjunction, cyclin B destruction is required for anaphase B and cytokinesis and for directional stability of univalent chromosome movements, and cyclin B3 degradation is required for proper spindle reorganization and restoration of the interphase nucleus. We suggest that the schedule of degradation of cyclin A, cyclin B, and then cyclin B3 contributes to the temporal coordination of mitotic events.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Devin H. Parry

  • Patrick H. O'Farrell

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free