A Mathematical Model of Mitotic Exit in Budding Yeast: The Role of Polo Kinase
Figure 1
Proposed wiring diagram of mitotic exit control in the budding yeast cell cycle.
For a full justification of this diagram with references, see Texts S1 and S2. Cdc28, the kinase partner of Clb2, is not shown explicitly in this diagram. Cdc20 and Cdh1 work in collaboration with the APC, which is also not shown explicitly in the diagram. All proteins (ovals) are assumed to be produced and degraded at specific rates. Four white circles represent degraded proteins. Solid lines correspond to chemical reactions, while dashed lines denote regulatory effects (enzyme catalysis). A protein sitting on a reaction arrow also represents an enzyme that catalyses the reaction. Cdc20 initiates the transition from metaphase to anaphase. Cdc14 released from PRENT and PRENTP induces exit from mitosis, i.e., activation of Cdh1 and establishment of the cell in G1 phase.