(A) Pfam regulation network predicted by the correlation of Family Regulation Profiles. In total, 89 Pfams and 781 correlations with PCC — 0.6 are shown (a network with each Pfam ID labeled is showed as an additional file (see Additional File 4: [supp4.png]). (B) 27 Pfams and 156 correlations with PCC — 0.75. (C)The derived 20-core subgraph from (A). The 20-core subset, which might represent the core networks of cell regulation, contains 27 Pfams.