Researchers have identified thousands of macromolecular interactions within cells, but joining them up in networks and figuring out how they work still poses a big challenge. Recently, improved methods and refinements in the computational tools used in modelling signaling pathways have helped researchers. To see protein interactions in different cell types, scientists are advancing the use of affinity-purification chromatography followed by mass spectrometry. Harvard University professor and SFI External Professor, Walter Fontana has co-founded a company called Plectix BioSystems and a web-based system called Cellucidate. Gordon Webster, vice-president of biology at Plectix says, “The model mirrors the behavior of the living system it represents: the biology that emerges from our models is the combinatorial expression of all these automata doing their own little thing — just the way it is in the cell.”