Genomic analysis of the four ecologically distinct cactus host populations of Drosophila mojavensis
AffiliationUniv Arizona, Dept Entomol
Univ Arizona, BIO5 Inst
Univ Arizona, Dept Ecol & Evolutionary Biol
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CitationAllan, C.W., Matzkin, L.M. Genomic analysis of the four ecologically distinct cactus host populations of Drosophila mojavensis. BMC Genomics 20, 732 (2019) doi:10.1186/s12864-019-6097-z
RightsCopyright © The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
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AbstractBackground Relationships between an organism and its environment can be fundamental in the understanding how populations change over time and species arise. Local ecological conditions can shape variation at multiple levels, among these are the evolutionary history and trajectories of coding genes. This study examines the rate of molecular evolution at protein-coding genes throughout the genome in response to host adaptation in the cactophilic Drosophila mojavensis. These insects are intimately associated with cactus necroses, developing as larvae and feeding as adults in these necrotic tissues. Drosophila mojavensis is composed of four isolated populations across the deserts of western North America and each population has adapted to utilize different cacti that are chemically, nutritionally, and structurally distinct. Results High coverage Illumina sequencing was performed on three previously unsequenced populations of D. mojavensis. Genomes were assembled using the previously sequenced genome of D. mojavensis from Santa Catalina Island (USA) as a template. Protein coding genes were aligned across all four populations and rates of protein evolution were determined for all loci using a several approaches. Conclusions Loci that exhibited elevated rates of molecular evolution tend to be shorter, have fewer exons, low expression, be transcriptionally responsive to cactus host use and have fixed expression differences across the four cactus host populations. Fast evolving genes were involved with metabolism, detoxification, chemosensory reception, reproduction and behavior. Results of this study give insight into the process and the genomic consequences of local ecological adaptation.
NoteOpen access journal
VersionFinal published version
SponsorsJunior Faculty Distinguished Research award from the University of Alabama in Huntsville; National Science FoundationNational Science Foundation (NSF) [DEB-1219387, IOS-1557697]
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