Figure 4

Degree distributions of proteins for the bipartite network if (a) only core proteins are considered and (b) only attachment proteins are considered. Here, the degree in (a) corresponds to the number of complexes in which a protein participates as a core component, and the degree in (b) corresponds to the number of complexes in which a protein participates as an attachment component. The blue squares correspond to the cumulative degree distribution P(k) = ∑_{k′ ≥ k}p(k′). The pink lines and gray curves are the best exponential and power-law fittings, respectively.