Figure 4. Synthesis and degradation.

A. The non-strongly connected graph in Figure 2A is augmented with partial edges denoting synthesis and degradation to form the partial graph B. By introducing a new vertex, , the partial graph is transformed into the labelled, directed graph, , which, in this case, is strongly connected. C. The linear system of ODEs arising from the partial graph . D. The Laplacian dynamics defined by the graph . Since, in this case, is strongly connected, the MTT can be applied to calculate the unique steady state of , as given in equation (23). The details of the calculation are given in Supporting Information S1.