Interaction Motifs in Regulatory Networks and Structural Robustness

If we consider the regulatory networks used in systems biology, we observe certain regularities in their architecture, namely the occurrence of interaction motifs, i.e. of oriented sub-graphs relating their elements with the same interaction scheme. We propose to describe some of these universal motifs and to study their main dynamical properties especially concerning their robustness (called also structural stability), i.e. their ability to keep after topological or dynamical perturbations, their essential asymptotic features, as their attractors number, shape and behavior, like their periodicity.