Network analysis of cell adhesion: Adhesomes as context-defined subnetworks.

Complex systems consisting of diverse interlinked elements are often represented as networks and are described according to the principles of network analysis. Among the networks of biological interest, several protein-protein interactomes have been reported in recent years, mostly in conjunction with high-throughput assays and extensive efforts of literature mining. The resulting global networks display well-defined topological properties and provide a comprehensive view of all the biological contexts in which a given interactome is involved. Global networks, however, do not provide enough information about the specific contexts, such as biological processes and subcellular compartments in which the individual interactions occur. Thus, to glean additional insights, it is often advantageous to extract context-defined local subnetworks from the global networks. Our recently published network analysis of the cell-cell adhesome, i.e., the protein-protein interaction subnetwork that underlies both the biological process of cell-cell adhesion and the subcellular compartment of the apical junctions in human epithelial cells, is an example of such context-defined approaches.