Figure 5.

Degradation without Competition Cannot Break PLK4 Symmetry

Phase space dynamics of the model with two centriolar compartments is shown qualitatively for three different scenarios.

(A) Linear degradation of PLK4 without competition between the compartments.

(B) Linear degradation of PLK4 with competition (base model).

(C) Nonlinear degradation of PLK4 without competition. Arrows indicate the direction of temporary dynamics. Stable steady states are shown as filled circles, unstable steady states are denoted by open circles (saddles, black; a repeller, red). In (B) red arrows indicate trajectories separating basins of attraction of two stable states, purple arrows show typical system trajectories in the presence of molecular noise. In (C) basins of attraction are shown in color (low symmetric state, light magenta; asymmetric states, light cyan).