FIGURE 2.

Network structure and topology. (A) The organization of nodes and edges in a graph represents network structure. Vertices and links represent nodes and edges, respectively. Two nodes can be connected by undirected or directed edges. (B) A sub-network of plant–pathogen interactions is demonstrated. Hubs (highly connected proteins), bottlenecks (high betweenness nodes), and pathogen effectors (virulence factors) are depicted in red, yellow, and brown colors, respectively. Network with scale-free topology might be vulnerable to pathogen-mediated perturbations.