The optimal ceRNA regulatory network. (A) Cumulative distribution functions of correlation coefficients of optimal ceRNA pairs satisfying four optimal conditions, other ceRNA pairs, and non-ceRNA pairs. (B) The optimal ceRNA regulatory network. The network is constructed by merging the identified 551,175 optimal ceRNA pairs comprising 2,405 ceRNAs. Nodes and edges denote ceRNAs and optimal regulatory relationship, respectively. (C) The subnetwork of intracellular transport (GO:0046907), generated by extracting 181 genes related to the function and corresponding ceRNA regulatory pairs from (B). Node size is proportional to the number of first-order neighbors and nodes accounting for more than 1% of all intra-function ceRNA regulating pairs are labeled with gene symbols. (D) The subnetwork of protein localization (GO:0008104).