title: Unraveling adaptive evolution: how a single point mutation affects the protein coregulation network.
abstract: Understanding the mechanisms of evolution requires identification of the molecular basis of the multiple (pleiotropic) effects of specific adaptive mutations. We have characterized the pleiotropic effects on protein levels of an adaptive single-base pair substitution in the coding sequence of a signaling pathway gene in the bacterium Pseudomonas fluorescens SBW25. We find 52 proteomic changes, corresponding to 46 identified proteins. None of these proteins is required for the adaptive phenotype. Instead, many are found within specific metabolic pathways associated with fitness-reducing (that is, antagonistic) effects of the mutation. The affected proteins fall within a single coregulatory network. The mutation 'rewires' this network by drawing particular proteins into tighter coregulating relationships. Although these changes are specific to the mutation studied, the quantitatively altered proteins are also affected in a coordinated way in other examples of evolution to the same niche.
authors.affiliation: Department of Plant Sciences, South Parks Road, Oxford OX1 3RB, UK. chris.knight@manchester.ac.uk
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Knight
authors.forename: Nicole
authors.initials: N
authors.lastname: Zitzmann
authors.forename: Sripadi
authors.initials: S
authors.lastname: Prabhakar
authors.forename: Robin
authors.initials: R
authors.lastname: Antrobus
authors.forename: Raymond
authors.initials: R
authors.lastname: Dwek
authors.forename: Holger
authors.initials: H
authors.lastname: Hebestreit
authors.forename: Paul B
authors.initials: PB
authors.lastname: Rainey
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D019143:Evolution, Molecular; D005798:Genes, Bacterial; D010802:Phylogeny; D017354:Point Mutation; D020543:Proteome / Q000032:analysis; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000502:physiology; D012984:Software; D013045:Species Specificity
chemical_list: D001426:Bacterial Proteins; D020543:Proteome