title: Cumulative impact of chaperone-mediated folding on genome evolution.
abstract: Molecular chaperones support protein folding and unfolding along with assembly and translocation of protein complexes. Chaperones have been recognized as important mediators between an organismal genotype and phenotype as well as important maintainers of cellular fitness under environmental conditions that induce high mutational loads. Here we review recent studies revealing that the folding assistance supplied by chaperones is evident in genomic sequences implicating chaperone-mediated folding as an influential factor during protein evolution. Interaction of protein with chaperones ensures a proper folding and function, yet an adaptation to obligatory dependence on such assistance may be irreversible, representing an evolutionary trap. A correlation between the requirement for a chaperone and protein expression level indicates that the evolution of substrate-chaperone interaction is bounded by the required substrate abundance within the cell. Accumulating evidence suggests that the utility of chaperones is governed by a delicate balance between their help in mitigating the risks of protein misfolding and aggregate formation on one hand and the slower rate of protein maturation and the energetic cost of chaperone synthesis on the other.
authors.affiliation: Institute for Genomic Microbiology, Heinrich-Heine University of Düsseldorf, Düsseldorf, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Bogumil
authors.forename: Tal
authors.initials: T
authors.lastname: Dagan
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D018834:Chaperonin 60 / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000502:physiology; D019143:Evolution, Molecular; D016678:Genome; D018841:HSP90 Heat-Shock Proteins / Q000502:physiology; D006360:Heat-Shock Proteins / Q000502:physiology; D006801:Humans; D018832:Molecular Chaperones / Q000502:physiology*; D017510:Protein Folding; D021381:Protein Transport / Q000187:drug effects; D058767:Protein Unfolding / Q000187:drug effects; D057165:Proteostasis Deficiencies
chemical_list: D001426:Bacterial Proteins; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; C028715:GroE protein, E coli; D018841:HSP90 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones