Example layouts for the HPRD network. (A) yFiles Organic layout (ORL). (B) Cytoscape's Spring-embedded layout (SEL). (C) Cytoscape's Force-directed layout (FDL). (D) Multilevel layout with the clustering option (MLL-C). The HPRD network consists of 5699 protein nodes and 19,779 literature-curated protein-protein interactions. A high-resolution version of the layout solutions of the four layout algorithms is provided in Additional File 8.