Modification of Gene Duplicability during the Evolution of Protein Interaction Network
Figure 4
Properties of ancient and recent hubs.
(A) Degree (connectivity) and betweenness (centrality) of proteins encoded by duplicated and singleton genes of same age are compared using the Wilcoxon test and the obtained p-values are transformed into heatmaps. Each square represents genes that originated at a given internal node and the color represents the p-value. Red indicates that duplicated genes encode significantly more connected or more central proteins than singleton proteins; green indicates that proteins encoded by singleton genes are significantly more connected or more central than duplicated proteins. The lower bound of p-values is set equal to 10−3. (B) Functional differences are analyzed between (1) ancestral and recent human hubs; (2) all ancestral and all recent human genes; (3) all singletons and all duplicated human genes. For each comparison, significance is assessed with Fisher's exact test and the p-values are adjusted for the False Discovery Rate (FDR). Vertical bars correspond to individual GO terms that are further grouped into 12 functional categories. Blue bars represent the enrichment of duplicated, recent genes, or hubs, orange represents the enrichment of singletons, ancient genes, or hubs.