Fig. 1

An example of an AN model with 4 automata: a, b, c and d. Each box represents an automaton (modeling a biological component), circles represent their local states (corresponding to their discrete expression levels) and the local transitions are represented by arrows labeled by their necessary conditions (consisting of a set of local states from other automata). The automata a and c are either at level 0 or 1, and b and d have 3 levels (0, 1 and 2). The grayed local states stand for the network state \(\langle a_0, b_1, c_1, d_0 \rangle \)