title: Uncovering the co-evolutionary network among prokaryotic genes.
abstract: BACKGROUND
  Correlated events of gains and losses enable inference of co-evolution relations. The reconstruction of the co-evolutionary interactions network in prokaryotic species may elucidate functional associations among genes.
  
  
  RESULTS
  We developed a novel probabilistic methodology for the detection of co-evolutionary interactions between pairs of genes. Using this method we inferred the co-evolutionary network among 4593 Clusters of Orthologous Genes (COGs). The number of co-evolutionary interactions substantially differed among COGs. Over 40% were found to co-evolve with at least one partner. We partitioned the network of co-evolutionary relations into clusters and uncovered multiple modular assemblies of genes with clearly defined functions. Finally, we measured the extent to which co-evolutionary relations coincide with other cellular relations such as genomic proximity, gene fusion propensity, co-expression, protein-protein interactions and metabolic connections. Our results show that co-evolutionary relations only partially overlap with these other types of networks. Our results suggest that the inferred co-evolutionary network in prokaryotes is highly informative towards revealing functional relations among genes, often showing signals that cannot be extracted from other network types.
  
  
  METHODS
  Available under GPL license as open source.
  
  
  BACKGROUND
  talp@post.tau.ac.il.
  
  
  BACKGROUND
  Supplementary data are available at Bioinformatics online.
authors.affiliation: Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Ofir
authors.initials: O
authors.lastname: Cohen
authors.forename: Haim
authors.initials: H
authors.lastname: Ashkenazy
authors.forename: David
authors.initials: D
authors.lastname: Burstein
authors.forename: Tal
authors.initials: T
authors.lastname: Pupko
mesh_terms: D019143:Evolution, Molecular; D005798:Genes, Bacterial; D016678:Genome; D023281:Genomics; D008957:Models, Genetic; D005810:Multigene Family; D010802:Phylogeny; D011336:Probability