Figure 1
From: A methodology for the structural and functional analysis of signaling and regulatory networks
(a) Example of a typical signaling pathway where mass and signal flow occur simultaneosly (Rec = receptor; Lig = ligand; RecLig* = (active) receptor-ligand-complex; M = molecule; M-P = phosphorylated molecule M). (b) The (only) elementary mode in this example which follows when M, M-P, ADP, ATP, Rec and Lig are considered as external (boundary) species. The involved reactions are indicated by green, thick arrows. In its net stoichiometry, this elementary mode converts M and ATP into M-P and ADP, whereas RecLig* is recycled in the overall process. Importantly, the mandatory process of building the receptor-ligand-complex RecLig* (hence, the causal dependeny of M-P from the availability of Rec and Lig) is not reflected by this mode.