title: Rapid evolution and gene expression: a rapidly evolving Mendelian trait that silences field crickets has widespread effects on mRNA and protein expression.
abstract: A major advance in modern evolutionary biology is the ability to start linking phenotypic evolution in the wild with genomic changes that underlie that evolution. We capitalized on a rapidly evolving Hawaiian population of crickets (Teleogryllus oceanicus) to test hypotheses about the genomic consequences of a recent Mendelian mutation of large effect which disrupts the development of sound-producing structures on male forewings. The resulting silent phenotype, flatwing, persists because of natural selection imposed by an acoustically orienting parasitoid, but it interferes with mate attraction. We examined gene expression differences in developing wing buds of wild-type and flatwing male crickets using RNA-seq and quantitative proteomics. Most differentially expressed (DE) transcripts were down-regulated in flatwing males (625 up vs. 1716 down), whereas up- and down-regulated proteins were equally represented (30 up and 34 down). Differences between morphs were clearly not restricted to a single pathway, and we recovered annotations associated with a broad array of functions that would not be predicted a priori. Using a candidate gene detection test based on homology, we identified 30% of putative Drosophila wing development genes in the cricket transcriptome, but only 10% were DE. In addition to wing-related annotations, endocrine pathways and several biological processes such as reproduction, immunity and locomotion were DE in the mutant crickets at both biological levels. Our results illuminate the breadth of genetic pathways that are potentially affected in the early stages of adaptation.
authors.affiliation: Centre for Biological Diversity, University of St Andrews, St Andrews, UK.
authors.forename: S
authors.initials: S
authors.lastname: Pascoal
authors.affiliation: Centre for Genomic Research, University of Liverpool, Liverpool, UK.
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.affiliation: Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee, UK.
authors.forename: T
authors.initials: T
authors.lastname: Ly
authors.affiliation: Centre for Genomic Research, University of Liverpool, Liverpool, UK.
authors.forename: Y
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Centre for Genomic Research, University of Liverpool, Liverpool, UK.
authors.forename: N
authors.initials: N
authors.lastname: Rockliffe
authors.affiliation: Centre for Genomic Research, University of Liverpool, Liverpool, UK.
authors.forename: S
authors.initials: S
authors.lastname: Paterson
authors.affiliation: School of Chemistry, Biomedical Sciences Research Complex, BMS Annexe, University of St Andrews, St Andrews, UK.
authors.forename: S L
authors.initials: SL
authors.lastname: Shirran
authors.affiliation: School of Chemistry, Biomedical Sciences Research Complex, BMS Annexe, University of St Andrews, St Andrews, UK.
authors.forename: C H
authors.initials: CH
authors.lastname: Botting
authors.affiliation: Centre for Biological Diversity, University of St Andrews, St Andrews, UK.
authors.forename: N W
authors.initials: NW
authors.lastname: Bailey
mesh_terms: D000818:Animals; D014644:Genetic Variation; D006135:Gryllidae / Q000235:genetics*; D006254:Hawaii; D008124:Locomotion; D008297:Male; D010641:Phenotype; D040901:Proteomics; D012333:RNA, Messenger; D014921:Wings, Animal / Q000254:growth & development*
chemical_list: D012333:RNA, Messenger
keywords: Teleogryllus oceanicus; proteome; rapid evolution; transcriptome; wing mutation