Figure 3.

Possible cross-talks in a phosphorelay. (a) Four-layer phosphorelay with cross-activation—‘talk in’ (green)—and cross-inhibition—‘talk out’ (red). Note that these cross-talk reactions are modelled as self-phosphorylation (k₂₃, k₃₃, k₄₃) and self-dephosphorylation (k₂₂, k₃₂, k₄₂) in the model (equation (4.1)). (b) Heat map showing response level given the input at the top of the relay and the secondary signal coming from cross-talk. The location where cross-talk occurs and its nature (i.e. activating or deactivating) are indicated on each panel (see also electronic supplementary material, figure S5).