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Hale MC, Pearse DE, Campbell MA. Characterization and distribution of a 14-Mb chromosomal inversion in native populations of rainbow trout (Oncorhynchus mykiss). G3 (BETHESDA, MD.) 2024; 14:jkae100. [PMID: 38885060 DOI: 10.1093/g3journal/jkae100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 05/10/2024] [Indexed: 06/20/2024]
Abstract
Multiple studies in a range of taxa have found links between structural variants and the development of ecologically important traits. Such variants are becoming easier to find due, in large part, to the increase in the amount of genome-wide sequence data in nonmodel organisms. The salmonids (salmon, trout, and charr) are a taxonomic group with abundant genome-wide datasets due to their importance in aquaculture, fisheries, and variation in multiple ecologically important life-history traits. Previous research on rainbow trout (Oncorhynchus mykiss) has documented a large pericentric (∼55 Mb) chromosomal inversion (CI) on chromosome 5 (Omy05) and a second smaller (∼14 Mb) chromosome inversion on Omy20. While the Omy05 inversion appears to be associated with multiple adaptive traits, the inversion on Omy20 has received far less attention. In this study, we re-analyze RAD-seq and amplicon data from several populations of rainbow trout (O. mykiss) to better document the structure and geographic distribution of variation in the Omy20 CI. Moreover, we utilize phylogenomic techniques to characterize both the age- and the protein-coding gene content of the Omy20 CI. We find that the age of the Omy20 inversion dates to the early stages of O. mykiss speciation and predates the Omy05 inversion by ∼450,000 years. The 2 CIs differ further in terms of the frequency of the homokaryotypes. While both forms of the Omy05 CI are found across the eastern Pacific, the ancestral version of the Omy20 CI is restricted to the southern portion of the species range in California. Furthermore, the Omy20 inverted haplotype is comparable in genetic diversity to the ancestral form, whereas derived CIs typically show substantially reduced genetic diversity. These data contribute to our understanding of the age and distribution of a large CI in rainbow trout and provide a framework for researchers looking to document CIs in other nonmodel species.
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Affiliation(s)
- Matthew C Hale
- Department of Biology, Texas Christian University, Fort Worth, TX 76109, USA
| | - Devon E Pearse
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration, Santa Cruz, CA 95064, USA
| | - Matthew A Campbell
- Department of Animal Science, University of California Davis, Davis, CA 95616, USA
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2
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Mackintosh C, Scott MF, Reuter M, Pomiankowski A. Locally adaptive inversions in structured populations. Genetics 2024; 227:iyae073. [PMID: 38709495 DOI: 10.1093/genetics/iyae073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 04/05/2024] [Accepted: 04/16/2024] [Indexed: 05/07/2024] Open
Abstract
Inversions have been proposed to facilitate local adaptation, by linking together locally coadapted alleles at different loci. Prior work addressing this question theoretically has considered the spread of inversions in "continent-island" scenarios in which there is a unidirectional flow of maladapted migrants into the island population. In this setting, inversions capturing locally adaptive haplotypes are most likely to invade when selection is weak, because stronger local selection (i) more effectively purges maladaptive alleles and (ii) generates linkage disequilibrium between adaptive alleles, thus lessening the advantage of inversions. We show this finding only holds under limited conditions by studying the establishment of inversions in a more general two-deme model, which explicitly considers the dynamics of allele frequencies in both populations linked by bidirectional migration. In this model, the level of symmetry between demes can be varied from complete asymmetry (continent-island) to complete symmetry. For symmetric selection and migration, strong selection increases the allele frequency divergence between demes thereby increasing the frequency of maladaptive alleles in migrants, favoring inversions-the opposite of the pattern seen in the asymmetric continent-island scenario. We also account for the likelihood that a new inversion captures an adaptive haplotype in the first instance. When considering the combined process of capture and invasion in "continent island" and symmetric scenarios, relatively strong selection increases inversion establishment probability. Migration must also be low enough that the inversion is likely to capture an adaptive allele combination, but not so low as to eliminate the inversion's advantage. Overall, our analysis suggests that inversions are likely to harbor larger effect alleles that experience relatively strong selection.
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Affiliation(s)
- Carl Mackintosh
- Department of Genetics, Evolution, and Environment, University College London, Gower Street, London WC1E 6BT, UK
- CoMPLEX, University College London, Gower Street, London WC1E 6BT, UK
- CNRS, UMR7144 Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff 29680, France
- Sorbonne Universités, UPMC Université Paris VI, Roscoff 29680, France
| | - Michael F Scott
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Max Reuter
- Department of Genetics, Evolution, and Environment, University College London, Gower Street, London WC1E 6BT, UK
| | - Andrew Pomiankowski
- Department of Genetics, Evolution, and Environment, University College London, Gower Street, London WC1E 6BT, UK
- CoMPLEX, University College London, Gower Street, London WC1E 6BT, UK
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3
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Manthey JD, Spellman GM. Recombination rate variation shapes genomic variability of phylogeographic structure in a widespread North American songbird (Aves: Certhia americana). Mol Phylogenet Evol 2024; 196:108088. [PMID: 38697377 DOI: 10.1016/j.ympev.2024.108088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 04/11/2024] [Accepted: 04/24/2024] [Indexed: 05/05/2024]
Abstract
The nonrandom distribution of chromosomal characteristics and functional elements-genomic architecture-impacts the relative strengths and impacts of population genetic processes across the genome. Due to this relationship, genomic architecture has the potential to shape variation in population genetic structure across the genome. Population genetic structure has been shown to vary across the genome in a variety of taxa, but this body of work has largely focused on pairwise population genomic comparisons between closely related taxa. Here, we used whole genome sequencing of seven phylogeographically structured populations of a North American songbird, the Brown Creeper (Certhia americana), to determine the impacts of genomic architecture on phylogeographic structure variation across the genome. Using multiple methods to infer phylogeographic structure-ordination, clustering, and phylogenetic methods-we found that recombination rate variation explained a large proportion of phylogeographic structure variation. Genomic regions with low recombination showed phylogeographic structure consistent with the genome-wide pattern. In regions with high recombination, we found strong phylogeographic structure, but with discordant patterns relative to the genome-wide pattern. In regions with high recombination rate, we found that populations with small effective population sizes evolve relatively more rapidly than larger populations, leading to discordant signatures of phylogeographic structure. These results suggest that the interplay between recombination rate variation and effective population sizes shape the relative impacts of selection and genetic drift in different parts of the genome. Overall, the combined interactions of population genetic processes, genomic architecture, and effective population sizes shape patterns of variability in phylogeographic structure across the genome of the Brown Creeper.
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Affiliation(s)
- Joseph D Manthey
- Department of Biological Sciences, Texas Tech University. Lubbock, TX, USA.
| | - Garth M Spellman
- Department of Zoology, Denver Museum of Nature & Science, Denver, CO, USA
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4
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Bock DG, Baeckens S, Kolbe JJ, Losos JB. When adaptation is slowed down: Genomic analysis of evolutionary stasis in thermal tolerance during biological invasion in a novel climate. Mol Ecol 2024; 33:e17075. [PMID: 37489260 DOI: 10.1111/mec.17075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 06/25/2023] [Accepted: 07/04/2023] [Indexed: 07/26/2023]
Abstract
Research conducted during the past two decades has demonstrated that biological invasions are excellent models of rapid evolution. Even so, characteristics of invasive populations such as a short time for recombination to assemble optimal combinations of alleles may occasionally limit adaptation to new environments. Here, we investigated such genetic constraints to adaptation in the invasive brown anole (Anolis sagrei)-a tropical ectotherm that was introduced to the southeastern United States, a region with a much colder climate than in its native Caribbean range. We examined thermal physiology for 30 invasive populations and tested for a climatic cline in cold tolerance. Also, we used genomics to identify mechanisms that may limit adaptation. We found no support for a climatic cline, indicating that thermal tolerance did not shift adaptively. Concomitantly, population genomic results were consistent with the occurrence of recombination cold spots that comprise more than half of the genome and maintain long-range associations among alleles in invasive populations. These genomic regions overlap with both candidate thermal tolerance loci that we identified using a standard genome-wide association test. Moreover, we found that recombination cold spots do not have a large contribution to population differentiation in the invasive range, contrary to observations in the native range. We suggest that limited recombination is constraining the contribution of large swaths of the genome to adaptation in invasive brown anoles. Our study provides an example of evolutionary stasis during invasion and highlights the possibility that reduced recombination occasionally slows down adaptation in invasive populations.
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Affiliation(s)
- Dan G Bock
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
- Department of Biology, Washington University, St. Louis, Missouri, USA
| | - Simon Baeckens
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
- Evolution and Optics of Nanostructures Lab, Department of Biology, Ghent University, Ghent, Belgium
- Functional Morphology Lab, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Jason J Kolbe
- Department of Biological Sciences, University of Rhode Island, Kingston, Rhode Island, USA
| | - Jonathan B Losos
- Department of Biology, Washington University, St. Louis, Missouri, USA
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5
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Usai G, Fambrini M, Pugliesi C, Simoni S. Exploring the patterns of evolution: Core thoughts and focus on the saltational model. Biosystems 2024; 238:105181. [PMID: 38479653 DOI: 10.1016/j.biosystems.2024.105181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/29/2024] [Accepted: 03/08/2024] [Indexed: 03/18/2024]
Abstract
The Modern Synthesis, a pillar in biological thought, united Darwin's species origin concepts with Mendel's laws of character heredity, providing a comprehensive understanding of evolution within species. Highlighting phenotypic variation and natural selection, it elucidated the environment's role as a selective force, shaping populations over time. This framework integrated additional mechanisms, including genetic drift, random mutations, and gene flow, predicting their cumulative effects on microevolution and the emergence of new species. Beyond the Modern Synthesis, the Extended Evolutionary Synthesis expands perspectives by recognizing the role of developmental plasticity, non-genetic inheritance, and epigenetics. We suggest that these aspects coexist in the plant evolutionary process; in this context, we focus on the saltational model, emphasizing how saltation events, such as dichotomous saltation, chromosomal mutations, epigenetic phenomena, and polyploidy, contribute to rapid evolutionary changes. The saltational model proposes that certain evolutionary changes, such as the rise of new species, may result suddenly from single macromutations rather than from gradual changes in DNA sequences and allele frequencies within a species over time. These events, observed in domesticated and wild higher plants, provide well-defined mechanistic bases, revealing their profound impact on plant diversity and rapid evolutionary events. Notably, next-generation sequencing exposes the likely crucial role of allopolyploidy and autopolyploidy (saltational events) in generating new plant species, each characterized by distinct chromosomal complements. In conclusion, through this review, we offer a thorough exploration of the ongoing dissertation on the saltational model, elucidating its implications for our understanding of plant evolutionary processes and paving the way for continued research in this intriguing field.
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Affiliation(s)
- Gabriele Usai
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
| | - Marco Fambrini
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
| | - Claudio Pugliesi
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy.
| | - Samuel Simoni
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
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6
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Hu H, Scheben A, Wang J, Li F, Li C, Edwards D, Zhao J. Unravelling inversions: Technological advances, challenges, and potential impact on crop breeding. PLANT BIOTECHNOLOGY JOURNAL 2024; 22:544-554. [PMID: 37961986 PMCID: PMC10893937 DOI: 10.1111/pbi.14224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 10/11/2023] [Accepted: 10/22/2023] [Indexed: 11/15/2023]
Abstract
Inversions, a type of chromosomal structural variation, significantly influence plant adaptation and gene functions by impacting gene expression and recombination rates. However, compared with other structural variations, their roles in functional biology and crop improvement remain largely unexplored. In this review, we highlight technological and methodological advancements that have allowed a comprehensive understanding of inversion variants through the pangenome framework and machine learning algorithms. Genome editing is an efficient method for inducing or reversing inversion mutations in plants, providing an effective mechanism to modify local recombination rates. Given the potential of inversions in crop breeding, we anticipate increasing attention on inversions from the scientific community in future research and breeding applications.
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Affiliation(s)
- Haifei Hu
- Rice Research Institute, Guangdong Academy of Agricultural Sciences & Key Laboratory of Genetics and Breeding of High Quality Rice in Southern China (Co‐construction by Ministry and Province), Ministry of Agriculture and Rural Affairs & Guangdong Key Laboratory of New Technology in Rice Breeding & Guangdong Rice Engineering LaboratoryGuangzhouChina
| | - Armin Scheben
- Simons Center for Quantitative Biology, Cold Spring Harbor LaboratoryCold Spring HarborNew YorkUSA
| | - Jian Wang
- Rice Research Institute, Guangdong Academy of Agricultural Sciences & Key Laboratory of Genetics and Breeding of High Quality Rice in Southern China (Co‐construction by Ministry and Province), Ministry of Agriculture and Rural Affairs & Guangdong Key Laboratory of New Technology in Rice Breeding & Guangdong Rice Engineering LaboratoryGuangzhouChina
| | - Fangping Li
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, State Key Laboratory for Conservation and Utilization of Subtropical Agro‐BioresourcesSouth China Agricultural UniversityGuangzhouChina
| | - Chengdao Li
- Western Crop Genetics Alliance, Centre for Crop & Food Innovation, Food Futures Institute, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - David Edwards
- School of Biological SciencesUniversity of Western AustraliaPerthWestern AustraliaAustralia
- Australia & Centre for Applied BioinformaticsUniversity of Western AustraliaPerthWestern AustraliaAustralia
| | - Junliang Zhao
- Rice Research Institute, Guangdong Academy of Agricultural Sciences & Key Laboratory of Genetics and Breeding of High Quality Rice in Southern China (Co‐construction by Ministry and Province), Ministry of Agriculture and Rural Affairs & Guangdong Key Laboratory of New Technology in Rice Breeding & Guangdong Rice Engineering LaboratoryGuangzhouChina
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7
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Innes PA, Goebl AM, Smith CCR, Rosenberger K, Kane NC. Gene expression and alternative splicing contribute to adaptive divergence of ecotypes. Heredity (Edinb) 2024; 132:120-132. [PMID: 38071268 PMCID: PMC10924094 DOI: 10.1038/s41437-023-00665-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 11/23/2023] [Accepted: 11/24/2023] [Indexed: 03/10/2024] Open
Abstract
Regulation of gene expression is a critical link between genotype and phenotype explaining substantial heritable variation within species. However, we are only beginning to understand the ways that specific gene regulatory mechanisms contribute to adaptive divergence of populations. In plants, the post-transcriptional regulatory mechanism of alternative splicing (AS) plays an important role in both development and abiotic stress response, making it a compelling potential target of natural selection. AS allows organisms to generate multiple different transcripts/proteins from a single gene and thus may provide a source of evolutionary novelty. Here, we examine whether variation in alternative splicing and gene expression levels might contribute to adaptation and incipient speciation of dune-adapted prairie sunflowers in Great Sand Dunes National Park, Colorado, USA. We conducted a common garden experiment to assess transcriptomic variation among ecotypes and analyzed differential expression, differential splicing, and gene coexpression. We show that individual genes are strongly differentiated for both transcript level and alternative isoform proportions, even when grown in a common environment, and that gene coexpression networks are disrupted between ecotypes. Furthermore, we examined how genome-wide patterns of sequence divergence correspond to divergence in transcript levels and isoform proportions and find evidence for both cis and trans-regulation. Together, our results emphasize that alternative splicing has been an underappreciated mechanism providing source material for natural selection at short evolutionary time scales.
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Affiliation(s)
- Peter A Innes
- Ecology and Evolutionary Biology Department, University of Colorado, Boulder, CO, USA.
| | - April M Goebl
- Ecology and Evolutionary Biology Department, University of Colorado, Boulder, CO, USA
- Research and Conservation Department, Denver Botanic Gardens, Denver, CO, USA
| | - Chris C R Smith
- Ecology and Evolutionary Biology Department, University of Colorado, Boulder, CO, USA
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR, USA
| | - Kaylee Rosenberger
- Ecology and Evolutionary Biology Department, University of Colorado, Boulder, CO, USA
| | - Nolan C Kane
- Ecology and Evolutionary Biology Department, University of Colorado, Boulder, CO, USA
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8
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Jay P, Aubier TG, Joron M. The interplay of local adaptation and gene flow may lead to the formation of supergenes. Mol Ecol 2024:e17297. [PMID: 38415327 DOI: 10.1111/mec.17297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 12/28/2023] [Accepted: 01/10/2024] [Indexed: 02/29/2024]
Abstract
Supergenes are genetic architectures resulting in the segregation of alternative combinations of alleles underlying complex phenotypes. The co-segregation of alleles at linked loci is often facilitated by polymorphic chromosomal rearrangements suppressing recombination locally. Supergenes are involved in many complex polymorphisms, including sexual, colour or behavioural polymorphisms in numerous plants, fungi, mammals, fish, and insects. Despite a long history of empirical and theoretical research, the formation of supergenes remains poorly understood. Here, using a two-island population genetic model, we explore how gene flow and the evolution of overdominant chromosomal inversions may jointly lead to the formation of supergenes. We show that the evolution of inversions in differentiated populations, both under disruptive selection, leads to an increase in frequency of poorly adapted, immigrant haplotypes. Indeed, rare allelic combinations, such as immigrant haplotypes, are more frequently reshuffled by recombination than common allelic combinations, and therefore benefit from the recombination suppression generated by inversions. When an inversion capturing a locally adapted haplotype spreads but is associated with a fitness cost hampering its fixation (e.g. a recessive mutation load), the maintenance of a non-inverted haplotype in the population is enhanced; under certain conditions, the immigrant haplotype persists alongside the inverted local haplotype, while the standard local haplotype disappears. This establishes a stable, local polymorphism with two non-recombining haplotypes encoding alternative adaptive strategies, that is, a supergene. These results bring new light to the importance of local adaptation, overdominance, and gene flow in the formation of supergenes and inversion polymorphisms in general.
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Affiliation(s)
- Paul Jay
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), Université de Montpellier, CNRS, EPHE, IRD, Montpellier, France
- Center for GeoGenetics, University of Copenhagen, Copenhagen, Denmark
| | - Thomas G Aubier
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, USA
- Centre de Recherche sur la Biodiversité et l'Environnement (CRBE), Université de Toulouse, CNRS, IRD, Toulouse INP, Université Toulouse 3 - Paul Sabatier (UT3), Toulouse, France
| | - Mathieu Joron
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), Université de Montpellier, CNRS, EPHE, IRD, Montpellier, France
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9
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Schreiber M, Jayakodi M, Stein N, Mascher M. Plant pangenomes for crop improvement, biodiversity and evolution. Nat Rev Genet 2024:10.1038/s41576-024-00691-4. [PMID: 38378816 DOI: 10.1038/s41576-024-00691-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2023] [Indexed: 02/22/2024]
Abstract
Plant genome sequences catalogue genes and the genetic elements that regulate their expression. Such inventories further research aims as diverse as mapping the molecular basis of trait diversity in domesticated plants or inquiries into the origin of evolutionary innovations in flowering plants millions of years ago. The transformative technological progress of DNA sequencing in the past two decades has enabled researchers to sequence ever more genomes with greater ease. Pangenomes - complete sequences of multiple individuals of a species or higher taxonomic unit - have now entered the geneticists' toolkit. The genomes of crop plants and their wild relatives are being studied with translational applications in breeding in mind. But pangenomes are applicable also in ecological and evolutionary studies, as they help classify and monitor biodiversity across the tree of life, deepen our understanding of how plant species diverged and show how plants adapt to changing environments or new selection pressures exerted by human beings.
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Affiliation(s)
- Mona Schreiber
- Department of Biology, University of Marburg, Marburg, Germany
| | - Murukarthick Jayakodi
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Nils Stein
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
- Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Martin Mascher
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany.
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.
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10
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Howe NS, Hale MC, Waters CD, Schaal SM, Shedd KR, Larson WA. Genomic evidence for domestication selection in three hatchery populations of Chinook salmon, Oncorhynchus tshawytscha. Evol Appl 2024; 17:e13656. [PMID: 38357359 PMCID: PMC10866082 DOI: 10.1111/eva.13656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 02/16/2024] Open
Abstract
Fish hatcheries are widely used to enhance fisheries and supplement declining wild populations. However, substantial evidence suggests that hatchery fish are subject to differential selection pressures compared to their wild counterparts. Domestication selection, or adaptation to the hatchery environment, poses a risk to wild populations if traits specific to success in the hatchery environment have a genetic component and there is subsequent introgression between hatchery and wild fish. Few studies have investigated domestication selection in hatcheries on a genomic level, and even fewer have done so in parallel across multiple hatchery-wild population pairs. In this study, we used low-coverage whole-genome sequencing to investigate signals of domestication selection in three separate hatchery populations of Chinook salmon, Oncorhynchus tshawytscha, after approximately seven generations of divergence from their corresponding wild progenitor populations. We sequenced 192 individuals from populations across Southeast Alaska and estimated genotype likelihoods at over six million loci. We discovered a total of 14 outlier peaks displaying high genetic differentiation (F ST) between hatchery-wild pairs, although no peaks were shared across the three comparisons. Peaks were small (53 kb on average) and often displayed elevated absolute genetic divergence (D xy) and linkage disequilibrium, suggesting some level of domestication selection has occurred. Our study provides evidence that domestication selection can lead to genetic differences between hatchery and wild populations in only a few generations. Additionally, our data suggest that population-specific adaptation to hatchery environments likely occurs through different genetic pathways, even for populations with similar standing genetic variation. These results highlight the need to collect paired genotype-phenotype data to understand how domestication may be affecting fitness and to identify potential management practices that may mitigate genetic risks despite multiple pathways of domestication.
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Affiliation(s)
- Natasha S. Howe
- Department of BiologyTexas Christian UniversityFort WorthTexasUSA
| | - Matthew C. Hale
- Department of BiologyTexas Christian UniversityFort WorthTexasUSA
| | - Charles D. Waters
- National Oceanographic and Atmospheric Administration, National Marine Fisheries ServiceAlaska Fisheries Science Center, Auke Bay LaboratoriesJuneauAlaskaUSA
| | - Sara M. Schaal
- National Oceanographic and Atmospheric Administration, National Marine Fisheries ServiceAlaska Fisheries Science Center, Auke Bay LaboratoriesJuneauAlaskaUSA
| | - Kyle R. Shedd
- Alaska Department of Fish and Game, Division of Commercial FisheriesGene Conservation LaboratoryAnchorageAlaskaUSA
| | - Wesley A. Larson
- National Oceanographic and Atmospheric Administration, National Marine Fisheries ServiceAlaska Fisheries Science Center, Auke Bay LaboratoriesJuneauAlaskaUSA
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11
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Goebl AM, Kane NC, Doak DF, Rieseberg LH, Ostevik KL. Adaptation to distinct habitats is maintained by contrasting selection at different life stages in sunflower ecotypes. Mol Ecol 2024; 33:e16785. [PMID: 36374153 DOI: 10.1111/mec.16785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/20/2022] [Accepted: 11/02/2022] [Indexed: 11/16/2022]
Abstract
Conspecific populations living in adjacent but contrasting microenvironments represent excellent systems for studying natural selection. These systems are valuable because gene flow is expected to force genetic homogeneity except at loci experiencing divergent selection. A history of reciprocal transplant and common garden studies in such systems, and a growing number of genomic studies, have contributed to understanding how selection operates in natural populations. While selection can vary across different fitness components and life stages, few studies have investigated how this ultimately affects allele frequencies and the maintenance of divergence between populations. Here, we study two sunflower ecotypes in distinct, adjacent habitats by combining demographic models with genome-wide sequence data to estimate fitness and allele frequency change at multiple life stages. This framework allows us to estimate that only local ecotypes are likely to experience positive population growth (λ > 1) and that the maintenance of divergent adaptation appears to be mediated via habitat- and life stage-specific selection. We identify genetic variation, significantly driven by loci in chromosomal inversions, associated with different life history strategies in neighbouring ecotypes that optimize different fitness components and may contribute to the maintenance of distinct ecotypes.
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Affiliation(s)
- April M Goebl
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, USA
| | - Nolan C Kane
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, USA
| | - Daniel F Doak
- Environmental Studies Programme, University of Colorado, Boulder, Colorado, USA
| | - Loren H Rieseberg
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kate L Ostevik
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Evolution, Ecology and Organismal Biology, University of California Riverside, Riverside, California, USA
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12
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Ali HAA, Coulson T, Clegg SM, Quilodrán CS. The effect of divergent and parallel selection on the genomic landscape of divergence. Mol Ecol 2024; 33:e17225. [PMID: 38063473 DOI: 10.1111/mec.17225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/25/2023] [Accepted: 11/16/2023] [Indexed: 01/25/2024]
Abstract
While the role of selection in divergence along the speciation continuum is theoretically well understood, defining specific signatures of selection in the genomic landscape of divergence is empirically challenging. Modelling approaches can provide insight into the potential role of selection on the emergence of a heterogenous genomic landscape of divergence. Here, we extend and apply an individual-based approach that simulates the phenotypic and genotypic distributions of two populations under a variety of selection regimes, genotype-phenotype maps, modes of migration, and genotype-environment interactions. We show that genomic islands of high differentiation and genomic valleys of similarity may respectively form under divergent and parallel selection between populations. For both types of between-population selection, negative and positive frequency-dependent selection within populations generated genomic islands of higher magnitude and genomic valleys of similarity, respectively. Divergence rates decreased under strong dominance with divergent selection, as well as in models including genotype-environment interactions under parallel selection. For both divergent and parallel selection models, divergence rate was higher under an intermittent migration regime between populations, in contrast to a constant level of migration across generations, despite an equal number of total migrants. We highlight that interpreting a particular evolutionary history from an observed genomic pattern must be done cautiously, as similar patterns may be obtained from different combinations of evolutionary processes. Modelling approaches such as ours provide an opportunity to narrow the potential routes that generate the genomic patterns of specific evolutionary histories.
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Affiliation(s)
- Hisham A A Ali
- Department of Biology, Edward Grey Institute of Field Ornithology, University of Oxford, Oxford, UK
| | - Tim Coulson
- Department of Biology, Edward Grey Institute of Field Ornithology, University of Oxford, Oxford, UK
| | - Sonya M Clegg
- Department of Biology, Edward Grey Institute of Field Ornithology, University of Oxford, Oxford, UK
| | - Claudio S Quilodrán
- Department of Biology, Edward Grey Institute of Field Ornithology, University of Oxford, Oxford, UK
- Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland
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13
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Zhou W, Zhang N, Huang K, Lin H, Tu J, Zheng C, Que P, Chiang CY, Martinez J, Naerhulan H, Székely T, Zhang Z, Liu Y. Divergent Selection in Low Recombination Regions Shapes the Genomic Islands in Two Incipient Shorebird Species. Mol Biol Evol 2024; 41:msae006. [PMID: 38225175 PMCID: PMC10835341 DOI: 10.1093/molbev/msae006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 01/17/2024] Open
Abstract
Speciation in the face of gene flow is usually associated with a heterogeneous genomic landscape of divergence in nascent species pairs. However, multiple factors, such as divergent selection and local recombination rate variation, can influence the formation of these genomic islands. Examination of the genomic landscapes of species pairs that are still in the early stages of speciation provides an insight into this conundrum. In this study, population genomic analyses were undertaken using a wide range of sampling and whole-genome resequencing data from 96 unrelated individuals of Kentish plover (Charadrius alexandrinus) and white-faced plover (Charadrius dealbatus). We suggest that the two species exhibit varying levels of population admixture along the Chinese coast and on the Taiwan Island. Genome-wide analyses for introgression indicate that ancient introgression had occurred in Taiwan population, and gene flow is still ongoing in mainland coastal populations. Furthermore, we identified a few genomic regions with significant levels of interspecific differentiation and local recombination suppression, which contain several genes potentially associated with disease resistance, coloration, and regulation of plumage molting and thus may be relevant to the phenotypic and ecological divergence of the two nascent species. Overall, our findings suggest that divergent selection in low recombination regions may be a main force in shaping the genomic islands in two incipient shorebird species.
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Affiliation(s)
- Wenjun Zhou
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Nan Zhang
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
| | - Kaichi Huang
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, Bc, Canada
| | - Hongzhou Lin
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
| | - Jie Tu
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
| | - Chenqing Zheng
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
| | - Pinjia Que
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
- Sichuan Key Laboratory of Conservation Biology for Endangered Wildlife, Chengdu Research Base of Giant Panda Breeding, Sichuan Academy of Giant Panda, Chengdu, China
| | - Chung-Yu Chiang
- Department of Environmental Science, Tunghai University, Taichung, Taiwan, China
| | | | - Halimubieke Naerhulan
- Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - Tamás Székely
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
- Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - Zhengwang Zhang
- Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Yang Liu
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
- Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Bath, UK
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14
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James ME, Ortiz-Barrientos D. The genomic consequences of selection across development. Mol Ecol 2024; 33:e17280. [PMID: 38247305 DOI: 10.1111/mec.17280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 01/01/2024] [Accepted: 01/12/2024] [Indexed: 01/23/2024]
Abstract
Understanding how natural selection drives diversification in nature has been at the forefront of biological research for over a century. The main idea is simple: natural selection favours individuals best suited to pass on their genes. However, the journey from birth to reproduction is complex as organisms experience multiple developmental stages, each influenced by genetic and environmental factors (Orr, 2009). These complexities compound even further as each stage of development might be governed by a unique underlying set of alleles and genes. In this issue of Molecular Ecology, Goebl et al. (2022) examine the role of natural selection in driving ecotypic divergence across different life history stages of the prairie sunflower Helianthus petiolaris. The authors used reciprocal transplant experiments, demographic models, and genomic sequencing to explore fitness variation across developmental stages. They show how natural selection impacts population divergence across multiple life history stages and evaluate the resulting allele frequency changes. Goebl et al. link these results to the role of chromosomal inversions, thus furthering our understanding of how ecological divergence proceeds in the face of gene flow. Below, we explore these results in detail and complement their interpretation by considering the evolution of genetic correlations amongst traits governing fitness.
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Affiliation(s)
- Maddie E James
- School of the Environment, The University of Queensland, St Lucia, QLD, Australia
- Australian Research Council Centre of Excellence for Plant Success in Nature and Agriculture, St Lucia, QLD, Australia
| | - Daniel Ortiz-Barrientos
- School of the Environment, The University of Queensland, St Lucia, QLD, Australia
- Australian Research Council Centre of Excellence for Plant Success in Nature and Agriculture, St Lucia, QLD, Australia
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15
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Meyer L, Barry P, Riquet F, Foote A, Der Sarkissian C, Cunha RL, Arbiol C, Cerqueira F, Desmarais E, Bordes A, Bierne N, Guinand B, Gagnaire PA. Divergence and gene flow history at two large chromosomal inversions underlying ecotype differentiation in the long-snouted seahorse. Mol Ecol 2024:e17277. [PMID: 38279695 DOI: 10.1111/mec.17277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 12/18/2023] [Accepted: 01/04/2024] [Indexed: 01/28/2024]
Abstract
Chromosomal inversions can play an important role in divergence and reproductive isolation by building and maintaining distinct allelic combinations between evolutionary lineages. Alternatively, they can take the form of balanced polymorphisms that segregate within populations until one arrangement becomes fixed. Many questions remain about how inversion polymorphisms arise, how they are maintained over the long term, and ultimately, whether and how they contribute to speciation. The long-snouted seahorse (Hippocampus guttulatus) is genetically subdivided into geographic lineages and marine-lagoon ecotypes, with shared structural variation underlying lineage and ecotype divergence. Here, we aim to characterize structural variants and to reconstruct their history and suspected role in ecotype formation. We generated a near chromosome-level genome assembly and described genome-wide patterns of diversity and divergence through the analysis of 112 whole-genome sequences from Atlantic, Mediterranean, and Black Sea populations. By also analysing linked-read sequencing data, we found evidence for two chromosomal inversions that were several megabases in length and showed contrasting allele frequency patterns between lineages and ecotypes across the species range. We reveal that these inversions represent ancient intraspecific polymorphisms, one likely being maintained by divergent selection and the other by pseudo-overdominance. A possible selective coupling between the two inversions was further supported by the absence of specific haplotype combinations and a putative functional interaction between the two inversions in reproduction. Lastly, we detected gene flux eroding divergence between inverted alleles at varying levels for the two inversions, with a likely impact on their dynamics and contribution to divergence and speciation.
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Affiliation(s)
- Laura Meyer
- ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Pierre Barry
- ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos Universidade do Porto, Vairão, Portugal
| | | | - Andrew Foote
- Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Oslo, Norway
| | - Clio Der Sarkissian
- Centre for Anthropobiology and Genomics of Toulouse, CNRS, University of Toulouse Paul Sabatier, Toulouse, France
| | - Regina L Cunha
- Centre of Marine Sciences-CCMAR, University of Algarve, Faro, Portugal
| | | | | | - Erick Desmarais
- ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Anaïs Bordes
- ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Nicolas Bierne
- ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Bruno Guinand
- ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
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16
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Ferguson S, Jones A, Murray K, Andrew RL, Schwessinger B, Bothwell H, Borevitz J. Exploring the role of polymorphic interspecies structural variants in reproductive isolation and adaptive divergence in Eucalyptus. Gigascience 2024; 13:giae029. [PMID: 38869149 PMCID: PMC11170218 DOI: 10.1093/gigascience/giae029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 03/11/2024] [Accepted: 05/14/2024] [Indexed: 06/14/2024] Open
Abstract
Structural variations (SVs) play a significant role in speciation and adaptation in many species, yet few studies have explored the prevalence and impact of different categories of SVs. We conducted a comparative analysis of long-read assembled reference genomes of closely related Eucalyptus species to identify candidate SVs potentially influencing speciation and adaptation. Interspecies SVs can be either fixed differences or polymorphic in one or both species. To describe SV patterns, we employed short-read whole-genome sequencing on over 600 individuals of Eucalyptus melliodora and Eucalyptus sideroxylon, along with recent high-quality genome assemblies. We aligned reads and genotyped interspecies SVs predicted between species reference genomes. Our results revealed that 49,756 of 58,025 and 39,536 of 47,064 interspecies SVs could be typed with short reads in E. melliodora and E. sideroxylon, respectively. Focusing on inversions and translocations, symmetric SVs that are readily genotyped within both populations, 24 were found to be structural divergences, 2,623 structural polymorphisms, and 928 shared structural polymorphisms. We assessed the functional significance of fixed interspecies SVs by examining differences in estimated recombination rates and genetic differentiation between species, revealing a complex history of natural selection. Shared structural polymorphisms displayed enrichment of potentially adaptive genes. Understanding how different classes of genetic mutations contribute to genetic diversity and reproductive barriers is essential for understanding how organisms enhance fitness, adapt to changing environments, and diversify. Our findings reveal the prevalence of interspecies SVs and elucidate their role in genetic differentiation, adaptive evolution, and species divergence within and between populations.
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Affiliation(s)
- Scott Ferguson
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, 2600 Australia
| | - Ashley Jones
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, 2600 Australia
| | - Kevin Murray
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, 2600 Australia
- Department of Molecular Biology, Max Planck Institute for Biology Tübingen, Tübingen, 72076 Germany
| | - Rose L Andrew
- Botany & N.C.W. Beadle Herbarium, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia
| | - Benjamin Schwessinger
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, 2600 Australia
| | - Helen Bothwell
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, 2600 Australia
- Warnell School of Forestry & Natural Resources, University of Georgia, Athens 30602 GA, United States
| | - Justin Borevitz
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, 2600 Australia
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17
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Díaz-Arce N, Gagnaire PA, Richardson DE, Walter JF, Arnaud-Haond S, Fromentin JM, Brophy D, Lutcavage M, Addis P, Alemany F, Allman R, Deguara S, Fraile I, Goñi N, Hanke AR, Karakulak FS, Pacicco A, Quattro JM, Rooker JR, Arrizabalaga H, Rodríguez-Ezpeleta N. Unidirectional trans-Atlantic gene flow and a mixed spawning area shape the genetic connectivity of Atlantic bluefin tuna. Mol Ecol 2024; 33:e17188. [PMID: 37921120 DOI: 10.1111/mec.17188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 10/02/2023] [Accepted: 10/19/2023] [Indexed: 11/04/2023]
Abstract
The commercially important Atlantic bluefin tuna (Thunnus thynnus), a large migratory fish, has experienced notable recovery aided by accurate resource assessment and effective fisheries management efforts. Traditionally, this species has been perceived as consisting of eastern and western populations, spawning respectively in the Mediterranean Sea and the Gulf of Mexico, with mixing occurring throughout the Atlantic. However, recent studies have challenged this assumption by revealing weak genetic differentiation and identifying a previously unknown spawning ground in the Slope Sea used by Atlantic bluefin tuna of uncertain origin. To further understand the current and past population structure and connectivity of Atlantic bluefin tuna, we have assembled a unique dataset including thousands of genome-wide single-nucleotide polymorphisms (SNPs) from 500 larvae, young of the year and spawning adult samples covering the three spawning grounds and including individuals of other Thunnus species. Our analyses support two weakly differentiated but demographically connected ancestral populations that interbreed in the Slope Sea. Moreover, we also identified signatures of introgression from albacore (Thunnus alalunga) into the Atlantic bluefin tuna genome, exhibiting varied frequencies across spawning areas, indicating strong gene flow from the Mediterranean Sea towards the Slope Sea. We hypothesize that the observed genetic differentiation may be attributed to increased gene flow caused by a recent intensification of westward migration by the eastern population, which could have implications for the genetic diversity and conservation of western populations. Future conservation efforts should consider these findings to address potential genetic homogenization in the species.
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Affiliation(s)
- Natalia Díaz-Arce
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | | | - David E Richardson
- Northeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration (NOAA), Narragansett, Rhode Island, USA
| | - John F Walter
- Southeast Fisheries Sciences Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration (NOAA), Miami, Florida, USA
| | | | | | - Deirdre Brophy
- Marine and Freshwater Research Center, Atlantic Technological University (ATU), Galway City, Ireland
| | - Molly Lutcavage
- Large Pelagics Research Center, School for the Environment, University of Massachusetts Boston, Gloucester, Massachusetts, USA
| | - Piero Addis
- Department of Environmental and Life Science, University of Cagliari, Cagliari, Italy
| | - Francisco Alemany
- International Commission for the Conservation of Atlantic Tunas, GBYP, Madrid, Spain
| | - Robert Allman
- National Marine Fisheries Service, Southeast Fisheries Science Center, Panama City Laboratory, Panama City, Florida, USA
| | | | - Igaratza Fraile
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Pasaia, Spain
| | - Nicolas Goñi
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Pasaia, Spain
| | - Alex R Hanke
- St Andrews Biological Station, Fisheries and Oceans Canada, St. Andrews, New Brunswick, Canada
| | | | - Ashley Pacicco
- Cooperative Institute for Marine and Atmospheric Studies Rosenstiel School of Marine, Atmospheric and Earth Science, University of Miami, Miami, Florida, USA
| | - Joseph M Quattro
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina, USA
| | - Jay R Rooker
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas, USA
| | - Haritz Arrizabalaga
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Pasaia, Spain
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18
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Berdan EL, Barton NH, Butlin R, Charlesworth B, Faria R, Fragata I, Gilbert KJ, Jay P, Kapun M, Lotterhos KE, Mérot C, Durmaz Mitchell E, Pascual M, Peichel CL, Rafajlović M, Westram AM, Schaeffer SW, Johannesson K, Flatt T. How chromosomal inversions reorient the evolutionary process. J Evol Biol 2023; 36:1761-1782. [PMID: 37942504 DOI: 10.1111/jeb.14242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 09/13/2023] [Accepted: 10/05/2023] [Indexed: 11/10/2023]
Abstract
Inversions are structural mutations that reverse the sequence of a chromosome segment and reduce the effective rate of recombination in the heterozygous state. They play a major role in adaptation, as well as in other evolutionary processes such as speciation. Although inversions have been studied since the 1920s, they remain difficult to investigate because the reduced recombination conferred by them strengthens the effects of drift and hitchhiking, which in turn can obscure signatures of selection. Nonetheless, numerous inversions have been found to be under selection. Given recent advances in population genetic theory and empirical study, here we review how different mechanisms of selection affect the evolution of inversions. A key difference between inversions and other mutations, such as single nucleotide variants, is that the fitness of an inversion may be affected by a larger number of frequently interacting processes. This considerably complicates the analysis of the causes underlying the evolution of inversions. We discuss the extent to which these mechanisms can be disentangled, and by which approach.
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Affiliation(s)
- Emma L Berdan
- Bioinformatics Core, Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Nicholas H Barton
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Roger Butlin
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
- Ecology and Evolutionary Biology, School of Bioscience, The University of Sheffield, Sheffield, UK
| | - Brian Charlesworth
- Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Rui Faria
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal
- BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Vairão, Portugal
| | - Inês Fragata
- CHANGE - Global Change and Sustainability Institute/Animal Biology Department, cE3c - Center for Ecology, Evolution and Environmental Changes, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | | | - Paul Jay
- Center for GeoGenetics, University of Copenhagen, Copenhagen, Denmark
| | - Martin Kapun
- Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
- Central Research Laboratories, Natural History Museum of Vienna, Vienna, Austria
| | - Katie E Lotterhos
- Department of Marine and Environmental Sciences, Northeastern University, Boston, Massachusetts, USA
| | - Claire Mérot
- UMR 6553 Ecobio, Université de Rennes, OSUR, CNRS, Rennes, France
| | - Esra Durmaz Mitchell
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- Functional Genomics & Metabolism Research Unit, Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Marta Pascual
- Departament de Genètica, Microbiologia i Estadística, Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain
| | - Catherine L Peichel
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Marina Rafajlović
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
- Linnaeus Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
| | - Anja M Westram
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Stephen W Schaeffer
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Kerstin Johannesson
- Linnaeus Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
- Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, Strömstad, Sweden
| | - Thomas Flatt
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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19
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Ulmo‐Diaz G, Engman A, McLarney WO, Lasso Alcalá CA, Hendrickson D, Bezault E, Feunteun E, Prats‐Léon FL, Wiener J, Maxwell R, Mohammed RS, Kwak TJ, Benchetrit J, Bougas B, Babin C, Normandeau E, Djambazian HHV, Chen S, Reiling SJ, Ragoussis J, Bernatchez L. Panmixia in the American eel extends to its tropical range of distribution: Biological implications and policymaking challenges. Evol Appl 2023; 16:1872-1888. [PMID: 38143897 PMCID: PMC10739100 DOI: 10.1111/eva.13599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/25/2023] [Accepted: 09/06/2023] [Indexed: 12/26/2023] Open
Abstract
The American eel (Anguilla rostrata) has long been regarded as a panmictic fish and has been confirmed as such in the northern part of its range. In this paper, we tested for the first time whether panmixia extends to the tropical range of the species. To do so, we first assembled a reference genome (975 Mbp, 19 chromosomes) combining long (PacBio and Nanopore and short (Illumina paired-end) reads technologies to support both this study and future research. To test for population structure, we estimated genotype likelihoods from low-coverage whole-genome sequencing of 460 American eels, collected at 21 sampling sites (in seven geographic regions) ranging from Canada to Trinidad and Tobago. We estimated genetic distance between regions, performed ADMIXTURE-like clustering analysis and multivariate analysis, and found no evidence of population structure, thus confirming that panmixia extends to the tropical range of the species. In addition, two genomic regions with putative inversions were observed, both geographically widespread and present at similar frequencies in all regions. We discuss the implications of lack of genetic population structure for the species. Our results are key for the future genomic research in the American eel and the implementation of conservation measures throughout its geographic range. Additionally, our results can be applied to fisheries management and aquaculture of the species.
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Affiliation(s)
- Gabriela Ulmo‐Diaz
- Département de BiologieInstitut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecCanada
| | - Augustin Engman
- University of Tennessee Institute of Agriculture, School of Natural ResourcesKnoxvilleTennesseeUSA
| | | | | | - Dean Hendrickson
- Department of Integrative Biology and Biodiversity CollectionsUniversity of Texas at AustinAustinTexasUSA
| | - Etienne Bezault
- UMR 8067 BOREA, Biologie Organismes Écosystèmes Aquatiques (MNHN, CNRS, SU, IRD, UCN, UA)Université des AntillesPointe‐à‐PitreGuadeloupe
- Caribaea Initiative, Département de BiologieUniversité Des Antilles‐Campus de FouillolePointe‐à‐PitreGuadeloupeFrance
| | - Eric Feunteun
- UMR 7208 BOREABiologie Organismes Écosystèmes Aquatiques (MNHN, CNRS, SU,IRD, UCN, UA)Station Marine de DinardRennesFrance
- EPHE‐PSLCGEL (Centre de Géoécologie Littorale)DinardFrance
| | | | - Jean Wiener
- Fondation pour la Protection de la Biodiversité Marine (FoProBiM)CaracolHaiti
| | - Robert Maxwell
- Inland Fisheries SectionLouisiana Department of Wildlife and FisheriesLouisianaUSA
| | - Ryan S. Mohammed
- The University of the West Indies (UWI)St. AugustineTrinidad and Tobago
- Present address:
Department of Biological SciencesAuburn UniversityAuburnAlabamaUSA
| | - Thomas J. Kwak
- US Geological SurveyNorth Carolina Cooperative Fish and Wildlife Research UnitDepartment of Applied EcologyNorth Carolina State UniversityRaleighNorth CarolinaUSA
| | | | - Bérénice Bougas
- Département de BiologieInstitut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecCanada
| | - Charles Babin
- Département de BiologieInstitut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecCanada
| | - Eric Normandeau
- Département de BiologieInstitut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecCanada
| | - Haig H. V. Djambazian
- McGIll Genome Centre, Department of Human GeneticsVictor Phillip Dahdaleh Institute of Genomic MedicineMcGill UniversityMontrealQuebecCanada
| | - Shu‐Huang Chen
- McGIll Genome Centre, Department of Human GeneticsVictor Phillip Dahdaleh Institute of Genomic MedicineMcGill UniversityMontrealQuebecCanada
| | - Sarah J. Reiling
- McGIll Genome Centre, Department of Human GeneticsVictor Phillip Dahdaleh Institute of Genomic MedicineMcGill UniversityMontrealQuebecCanada
| | - Jiannis Ragoussis
- McGIll Genome Centre, Department of Human GeneticsVictor Phillip Dahdaleh Institute of Genomic MedicineMcGill UniversityMontrealQuebecCanada
| | - Louis Bernatchez
- Département de BiologieInstitut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecCanada
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20
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Bock DG, Cai Z, Elphinstone C, González-Segovia E, Hirabayashi K, Huang K, Keais GL, Kim A, Owens GL, Rieseberg LH. Genomics of plant speciation. PLANT COMMUNICATIONS 2023; 4:100599. [PMID: 37050879 PMCID: PMC10504567 DOI: 10.1016/j.xplc.2023.100599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/21/2023] [Accepted: 04/06/2023] [Indexed: 06/19/2023]
Abstract
Studies of plants have been instrumental for revealing how new species originate. For several decades, botanical research has complemented and, in some cases, challenged concepts on speciation developed via the study of other organisms while also revealing additional ways in which species can form. Now, the ability to sequence genomes at an unprecedented pace and scale has allowed biologists to settle decades-long debates and tackle other emerging challenges in speciation research. Here, we review these recent genome-enabled developments in plant speciation. We discuss complications related to identification of reproductive isolation (RI) loci using analyses of the landscape of genomic divergence and highlight the important role that structural variants have in speciation, as increasingly revealed by new sequencing technologies. Further, we review how genomics has advanced what we know of some routes to new species formation, like hybridization or whole-genome duplication, while casting doubt on others, like population bottlenecks and genetic drift. While genomics can fast-track identification of genes and mutations that confer RI, we emphasize that follow-up molecular and field experiments remain critical. Nonetheless, genomics has clarified the outsized role of ancient variants rather than new mutations, particularly early during speciation. We conclude by highlighting promising avenues of future study. These include expanding what we know so far about the role of epigenetic and structural changes during speciation, broadening the scope and taxonomic breadth of plant speciation genomics studies, and synthesizing information from extensive genomic data that have already been generated by the plant speciation community.
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Affiliation(s)
- Dan G Bock
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Zhe Cai
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Cassandra Elphinstone
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Eric González-Segovia
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | | | - Kaichi Huang
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Graeme L Keais
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Amy Kim
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Gregory L Owens
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Loren H Rieseberg
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada.
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21
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Euclide PT, Larson WA, Shi Y, Gruenthal K, Christensen KA, Seeb J, Seeb L. Conserved islands of divergence associated with adaptive variation in sockeye salmon are maintained by multiple mechanisms. Mol Ecol 2023. [PMID: 37695544 DOI: 10.1111/mec.17126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/01/2023] [Accepted: 08/14/2023] [Indexed: 09/12/2023]
Abstract
Local adaptation is facilitated by loci clustered in relatively few regions of the genome, termed genomic islands of divergence. The mechanisms that create and maintain these islands and how they contribute to adaptive divergence is an active research topic. Here, we use sockeye salmon as a model to investigate both the mechanisms responsible for creating islands of divergence and the patterns of differentiation at these islands. Previous research suggested that multiple islands contributed to adaptive radiation of sockeye salmon. However, the low-density genomic methods used by these studies made it difficult to fully elucidate the mechanisms responsible for islands and connect genotypes to adaptive variation. We used whole genome resequencing to genotype millions of loci to investigate patterns of genetic variation at islands and the mechanisms that potentially created them. We discovered 64 islands, including 16 clustered in four genomic regions shared between two isolated populations. Characterisation of these four regions suggested that three were likely created by structural variation, while one was created by processes not involving structural variation. All four regions were small (< 600 kb), suggesting low recombination regions do not have to span megabases to be important for adaptive divergence. Differentiation at islands was not consistently associated with established population attributes. In sum, the landscape of adaptive divergence and the mechanisms that create it are complex; this complexity likely helps to facilitate fine-scale local adaptation unique to each population.
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Affiliation(s)
- Peter T Euclide
- Department of Forestry and Natural Resources, Illinois-Indiana Sea Grant, Purdue University, West Lafayette, Indiana, USA
| | - Wesley A Larson
- National Oceanographic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center, Auke Bay Laboratories, Juneau, Alaska, USA
| | - Yue Shi
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, USA
| | - Kristen Gruenthal
- Alaska Department of Fish and Game, Juneau, Alaska, USA
- Office of Applied Science, Wisconsin Department of Natural Resources, Wisconsin Cooperative Fishery Research Unit, College of Natural Resources, University of Wisconsin-Stevens Point, Stevens Point, Wisconsin, USA
| | - Kris A Christensen
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Jim Seeb
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, USA
| | - Lisa Seeb
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, USA
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22
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Wessinger CA, Katzer AM, Hime PM, Rausher MD, Kelly JK, Hileman LC. A few essential genetic loci distinguish Penstemon species with flowers adapted to pollination by bees or hummingbirds. PLoS Biol 2023; 21:e3002294. [PMID: 37769035 PMCID: PMC10538765 DOI: 10.1371/journal.pbio.3002294] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 08/11/2023] [Indexed: 09/30/2023] Open
Abstract
In the formation of species, adaptation by natural selection generates distinct combinations of traits that function well together. The maintenance of adaptive trait combinations in the face of gene flow depends on the strength and nature of selection acting on the underlying genetic loci. Floral pollination syndromes exemplify the evolution of trait combinations adaptive for particular pollinators. The North American wildflower genus Penstemon displays remarkable floral syndrome convergence, with at least 20 separate lineages that have evolved from ancestral bee pollination syndrome (wide blue-purple flowers that present a landing platform for bees and small amounts of nectar) to hummingbird pollination syndrome (bright red narrowly tubular flowers offering copious nectar). Related taxa that differ in floral syndrome offer an attractive opportunity to examine the genomic basis of complex trait divergence. In this study, we characterized genomic divergence among 229 individuals from a Penstemon species complex that includes both bee and hummingbird floral syndromes. Field plants are easily classified into species based on phenotypic differences and hybrids displaying intermediate floral syndromes are rare. Despite unambiguous phenotypic differences, genome-wide differentiation between species is minimal. Hummingbird-adapted populations are more genetically similar to nearby bee-adapted populations than to geographically distant hummingbird-adapted populations, in terms of genome-wide dXY. However, a small number of genetic loci are strongly differentiated between species. These approximately 20 "species-diagnostic loci," which appear to have nearly fixed differences between pollination syndromes, are sprinkled throughout the genome in high recombination regions. Several map closely to previously established floral trait quantitative trait loci (QTLs). The striking difference between the diagnostic loci and the genome as whole suggests strong selection to maintain distinct combinations of traits, but with sufficient gene flow to homogenize the genomic background. A surprisingly small number of alleles confer phenotypic differences that form the basis of species identity in this species complex.
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Affiliation(s)
- Carolyn A. Wessinger
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina, United States of America
| | - Amanda M. Katzer
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, United States of America
| | - Paul M. Hime
- Biodiversity Institute and Natural History Museum, University of Kansas, Lawrence, Kansas, United States of America
| | - Mark D. Rausher
- Department of Biology, Duke University, Durham, North Carolina, United States of America
| | - John K. Kelly
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, United States of America
| | - Lena C. Hileman
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, United States of America
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23
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Yu X, Qin M, Qu M, Jiang Q, Guo S, Chen Z, Shen Y, Fu G, Fei Z, Huang H, Gao L, Yao X. Genomic analyses reveal dead-end hybridization between two deeply divergent kiwifruit species rather than homoploid hybrid speciation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1528-1543. [PMID: 37258460 DOI: 10.1111/tpj.16336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/24/2023] [Accepted: 05/29/2023] [Indexed: 06/02/2023]
Abstract
Despite the importance of hybridization in evolution, the evolutionary consequence of homoploid hybridizations in plants remains poorly understood. Specially, homoploid hybridization events have been rarely documented due to a lack of genomic resources and methodological limitations. Actinidia zhejiangensis was suspected to have arisen from hybridization of Actinidia eriantha and Actinidia hemsleyana or Actinidia rufa. However, this species was very rare in nature and exhibited sympatric distribution with its potential parent species, which implied it might be a spontaneous hybrid of ongoing homoploid hybridization. Here, we illustrate the dead-end homoploid hybridization and genomic basis of isolating barriers between A. eriantha and A. hemsleyana through whole genome sequencing and population genomic analyses. Chromosome-scale genome assemblies of A. zhejiangensis and A. hemsleyana were generated. The chromosomes of A. zhejiangensis are confidently assigned to the two haplomes, and one of them originates from A. eriantha and the other originates from A. hemsleyana. Whole genome resequencing data reveal that A. zhejiangensis are mainly F1 hybrids of A. hemsleyana and A. eriantha and gene flow initiated about 0.98 million years ago, implying both strong genetic barriers and ongoing hybridization between these two deeply divergent kiwifruit species. Five inversions containing genes involved in pollen germination and pollen tube growth might account for the fertility breakdown of hybrids between A. hemsleyana and A. eriantha. Despite its distinct morphological traits and long recurrent hybrid origination, A. zhejiangensis does not initiate speciation. Collectively, our study provides new insights into homoploid hybridization in plants and provides genomic resources for evolutionary and functional genomic studies of kiwifruit.
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Affiliation(s)
- Xiaofen Yu
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Hubei Hongshan Laboratory, Wuhan, Hubei, 430070, China
| | - Mengyun Qin
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Minghao Qu
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Quan Jiang
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Sumin Guo
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
| | - Zhenghai Chen
- Forest Resources Monitoring Center of Zhejiang Province, Hangzhou, Zhejiang, 310020, China
| | - Yufang Shen
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
| | - Guodong Fu
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhangjun Fei
- Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, New York, 14853, USA
- U.S. Department of Agriculture-Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Ithaca, New York, 14853, USA
| | - Hongwen Huang
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang, Jiangxi, 332900, China
| | - Lei Gao
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
- Hubei Hongshan Laboratory, Wuhan, Hubei, 430070, China
| | - Xiaohong Yao
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China
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24
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Reid BN, Star B, Pinsky ML. Detecting parallel polygenic adaptation to novel evolutionary pressure in wild populations: a case study in Atlantic cod ( Gadus morhua). Philos Trans R Soc Lond B Biol Sci 2023; 378:20220190. [PMID: 37246382 DOI: 10.1098/rstb.2022.0190] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 02/13/2023] [Indexed: 05/30/2023] Open
Abstract
Populations can adapt to novel selection pressures through dramatic frequency changes in a few genes of large effect or subtle shifts in many genes of small effect. The latter (polygenic adaptation) is expected to be the primary mode of evolution for many life-history traits but tends to be more difficult to detect than changes in genes of large effect. Atlantic cod (Gadus morhua) were subjected to intense fishing pressure over the twentieth century, leading to abundance crashes and a phenotypic shift toward earlier maturation across many populations. Here, we use spatially replicated temporal genomic data to test for a shared polygenic adaptive response to fishing using methods previously applied to evolve-and-resequence experiments. Cod populations on either side of the Atlantic show covariance in allele frequency change across the genome that are characteristic of recent polygenic adaptation. Using simulations, we demonstrate that the degree of covariance in allele frequency change observed in cod is unlikely to be explained by neutral processes or background selection. As human pressures on wild populations continue to increase, understanding and attributing modes of adaptation using methods similar to those demonstrated here will be important in identifying the capacity for adaptive responses and evolutionary rescue. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.
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Affiliation(s)
- Brendan N Reid
- Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, NJ 08540, USA
| | - Bastiaan Star
- Center for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316 Oslo, Norway
| | - Malin L Pinsky
- Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, NJ 08540, USA
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25
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Shinde SS, Sharma A, Vijay N. Decoding the fibromelanosis locus complex chromosomal rearrangement of black-bone chicken: genetic differentiation, selective sweeps and protein-coding changes in Kadaknath chicken. Front Genet 2023; 14:1180658. [PMID: 37424723 PMCID: PMC10325862 DOI: 10.3389/fgene.2023.1180658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 06/05/2023] [Indexed: 07/11/2023] Open
Abstract
Black-bone chicken (BBC) meat is popular for its distinctive taste and texture. A complex chromosomal rearrangement at the fibromelanosis (Fm) locus on the 20th chromosome results in increased endothelin-3 (EDN3) gene expression and is responsible for melanin hyperpigmentation in BBC. We use public long-read sequencing data of the Silkie breed to resolve high-confidence haplotypes at the Fm locus spanning both Dup1 and Dup2 regions and establish that the Fm_2 scenario is correct of the three possible scenarios of the complex chromosomal rearrangement. The relationship between Chinese and Korean BBC breeds with Kadaknath native to India is underexplored. Our data from whole-genome re-sequencing establish that all BBC breeds, including Kadaknath, share the complex chromosomal rearrangement junctions at the fibromelanosis (Fm) locus. We also identify two Fm locus proximal regions (∼70 Kb and ∼300 Kb) with signatures of selection unique to Kadaknath. These regions harbor several genes with protein-coding changes, with the bactericidal/permeability-increasing-protein-like gene having two Kadaknath-specific changes within protein domains. Our results indicate that protein-coding changes in the bactericidal/permeability-increasing-protein-like gene hitchhiked with the Fm locus in Kadaknath due to close physical linkage. Identifying this Fm locus proximal selective sweep sheds light on the genetic distinctiveness of Kadaknath compared to other BBC.
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Affiliation(s)
| | | | - Nagarjun Vijay
- Computational Evolutionary Genomics Lab, Department of Biological Sciences, IISER Bhopal, Bhauri, Madhya Pradesh, India
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26
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Makarenko MS, Azarin KV, Gavrilova VA. Mitogenomic Research of Silverleaf Sunflower ( Helianthus argophyllus) and Its Interspecific Hybrids. Curr Issues Mol Biol 2023; 45:4841-4849. [PMID: 37367057 DOI: 10.3390/cimb45060308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/28/2023] [Accepted: 05/30/2023] [Indexed: 06/28/2023] Open
Abstract
Interspecific hybridization is widespread for sunflowers, both in wild populations and commercial breeding. One of the most common species that can efficiently cross with Helianthus annuus is the Silverleaf sunflower-Helianthus argophyllus. The current study carried out structural and functional organization analyses of mitochondrial DNA in H. argophyllus and the interspecific hybrid, H. annuus (VIR114A line) × H. argophyllus. The complete mitogenome of H. argophyllus counts 300,843 bp, has a similar organization to the mitogenome of cultivated sunflower, and holds SNPs typical for wild sunflowers. RNA editing analysis predicted 484 sites in H. argophyllus mitochondrial CDS. The mitochondrial genome of the H. annuus × H. argophyllus hybrid is identical to the maternal line (VIR114A). We expected that significant rearrangements in the mitochondrial DNA of the hybrid would occur, due to the frequent recombination. However, the hybrid mitogenome lacks rearrangements, presumably due to the preservation of nuclear-cytoplasmic interaction paths.
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Affiliation(s)
- Maksim S Makarenko
- The Laboratory of Plant Genomics, The Institute for Information Transmission Problems, 127051 Moscow, Russia
| | - Kirill V Azarin
- The Laboratory of Molecular Genetics, Southern Federal University, 344006 Rostov-on-Don, Russia
| | - Vera A Gavrilova
- Oil and Fiber Crops Genetic Resources Department, The N.I. Vavilov All Russian Institute of Plant Genetic Resources, 190031 Saint Petersburg, Russia
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27
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Wold JR, Guhlin JG, Dearden PK, Santure AW, Steeves TE. The promise and challenges of characterizing genome-wide structural variants: A case study in a critically endangered parrot. Mol Ecol Resour 2023. [PMID: 36916824 DOI: 10.1111/1755-0998.13783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/24/2023] [Accepted: 03/09/2023] [Indexed: 03/15/2023]
Abstract
There is growing interest in the role of structural variants (SVs) as drivers of local adaptation and speciation. From a biodiversity genomics perspective, the characterization of genome-wide SVs provides an exciting opportunity to complement single nucleotide polymorphisms (SNPs). However, little is known about the impacts of SV discovery and genotyping strategies on the characterization of genome-wide SV diversity within and among populations. Here, we explore a near whole-species resequence data set, and long-read sequence data for a subset of highly represented individuals in the critically endangered kākāpō (Strigops habroptilus). We demonstrate that even when using a highly contiguous reference genome, different discovery and genotyping strategies can significantly impact the type, size and location of SVs characterized genome-wide. Further, we found that the mean number of SVs in each of two kākāpō lineages differed both within and across generations. These combined results suggest that genome-wide characterization of SVs remains challenging at the population-scale. We are optimistic that increased accessibility to long-read sequencing and advancements in bioinformatic approaches including multireference approaches like genome graphs will alleviate at least some of the challenges associated with resolving SV characteristics below the species level. In the meantime, we address caveats, highlight considerations, and provide recommendations for the characterization of genome-wide SVs in biodiversity genomic research.
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Affiliation(s)
- Jana R Wold
- University of Canterbury, Christchurch, New Zealand
| | - Joseph G Guhlin
- Genomics Aotearoa and Biochemistry Department, University of Otago, Dunedin, New Zealand
| | - Peter K Dearden
- Genomics Aotearoa and Biochemistry Department, University of Otago, Dunedin, New Zealand
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28
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Xie W, Guo Z, Wang J, He Z, Li Y, Feng X, Zhong C, Shi S. Evolution of woody plants to the land-sea interface - The atypical genomic features of mangroves with atypical phenotypic adaptation. Mol Ecol 2023; 32:1351-1365. [PMID: 35771769 DOI: 10.1111/mec.16587] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 11/30/2022]
Abstract
How plants adapt and diverge in extreme environments is a key question of plant evolution and ecology. Mangrove invasion of intertidal environments is facilitated by adaptive phenotypes such as aerial roots, salt-secreting leaf, and viviparity, and genomic mechanisms including whole genome duplication and transposable element number reduction. However, a number of mangroves lack these typical phenotypes. The question we ask is whether these phenotypically atypical mangroves also have distinct genomic features? The sibling mangrove species Lumnitzera littorea and Lumnitzera racemosa provide a model to study this question. We sequenced and assembled their genomes to chromosome level, together with a closely related species Combretum micranthum. While most mangroves have small genomes, the genomes of both Lumnitzera species are large (1443 and 1317 Mb) and carry a high proportion of repeat sequences (~75%). Moreover, Lumnitzera species have not undergone post-gamma whole-genome duplications. Their genome size increased mainly due to the expansion of repeat sequences in their ancestors. However, Lumnitzera genomes have reduced transposable elements by constraining the proliferation of new LTR-RTs. Meanwhile, the two species have more gene families contracted than expanded, and some gene families with reversed size change may underlie their differentiation in root morphology and local distribution. We identified 86 chromosomal inversions, five of which are measured between 6.5 and 12.8 megabases. A number of genes located in these inversions function in pigment biosynthesis, a process likely involved in flower colour differentiation between the Lumnitzera species. We conclude that the mangroves with atypical phenotypes also have atypical genomic evolution.
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Affiliation(s)
- Wei Xie
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Zixiao Guo
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Jiayan Wang
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Ziwen He
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Yulong Li
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, Guangdong, China.,School of Ecology, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Xiao Feng
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Cairong Zhong
- Hainan Academy of Forestry (Hainan Academy of Mangrove), Haikou, Hainan, China
| | - Suhua Shi
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, Guangdong, China
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29
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Zhang L, Chaturvedi S, Nice CC, Lucas LK, Gompert Z. Population genomic evidence of selection on structural variants in a natural hybrid zone. Mol Ecol 2023; 32:1497-1514. [PMID: 35398939 DOI: 10.1111/mec.16469] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/18/2022] [Accepted: 03/28/2022] [Indexed: 12/01/2022]
Abstract
Structural variants (SVs) can promote speciation by directly causing reproductive isolation or by suppressing recombination across large genomic regions. Whereas examples of each mechanism have been documented, systematic tests of the role of SVs in speciation are lacking. Here, we take advantage of long-read (Oxford nanopore) whole-genome sequencing and a hybrid zone between two Lycaeides butterfly taxa (L. melissa and Jackson Hole Lycaeides) to comprehensively evaluate genome-wide patterns of introgression for SVs and relate these patterns to hypotheses about speciation. We found >100,000 SVs segregating within or between the two hybridizing species. SVs and SNPs exhibited similar levels of genetic differentiation between species, with the exception of inversions, which were more differentiated. We detected credible variation in patterns of introgression among SV loci in the hybrid zone, with 562 of 1419 ancestry-informative SVs exhibiting genomic clines that deviated from null expectations based on genome-average ancestry. Overall, hybrids exhibited a directional shift towards Jackson Hole Lycaeides ancestry at SV loci, consistent with the hypothesis that these loci experienced more selection on average than SNP loci. Surprisingly, we found that deletions, rather than inversions, showed the highest skew towards excess ancestry from Jackson Hole Lycaeides. Excess Jackson Hole Lycaeides ancestry in hybrids was also especially pronounced for Z-linked SVs and inversions containing many genes. In conclusion, our results show that SVs are ubiquitous and suggest that SVs in general, but especially deletions, might disproportionately affect hybrid fitness and thus contribute to reproductive isolation.
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Affiliation(s)
- Linyi Zhang
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada.,Department of Biology, Utah State University, Logan, Utah, USA
| | - Samridhi Chaturvedi
- Department of Integrative Biology, University of California, Berkeley, California, USA
| | - Chris C Nice
- Department of Biology, Texas State University, San Marcos, Texas, USA
| | - Lauren K Lucas
- Department of Biology, Utah State University, Logan, Utah, USA
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30
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Pampoulie C, Berg PR, Jentoft S. Hidden but revealed: After years of genetic studies behavioural monitoring combined with genomics uncover new insight into the population dynamics of Atlantic cod in Icelandic waters. Evol Appl 2023; 16:223-233. [PMID: 36793686 PMCID: PMC9923494 DOI: 10.1111/eva.13471] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 05/29/2022] [Accepted: 08/18/2022] [Indexed: 11/27/2022] Open
Abstract
Stock structure is of paramount importance for sustainable management of exploited resources. In that context, genetic markers have been used for more than two decades to resolve spatial structure of marine exploited resources and to fully fathom stock dynamics and interactions. While genetic markers such as allozymes and RFLP dominated the debate in the early era of genetics, technology advances have provided scientists with new tools every decade to better assess stock discrimination and interactions (i.e. gene flow). Here, we provide a review of genetic studies performed to understand stock structure of Atlantic cod in Icelandic waters, from the early allozyme approaches to the genomic work currently carried out. We further highlight the importance of the generation of a chromosome-anchored genome assembly together with whole-genome population data, which drastically changed our perception of the possible management units to consider. After nearly 60 years of genetic investigation of Atlantic cod structure in Icelandic waters, genetic (and later genomic) data combined with behavioural monitoring using Data Storage Tags shifted the attention from geographical population structures to behavioural ecotypes. This review also demonstrates the need for future research to further disentangle the impact of these ecotypes (and gene flow among them) on the population structure of Atlantic cod in Icelandic waters. It also highlights the importance of whole-genome data to unravel unexpected within-species diversity related to chromosomal inversions and associated supergenes, which are important to consider for future development of sustainable management programmes of the species within the North Atlantic.
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Affiliation(s)
| | - Paul Ragnar Berg
- Norwegian Institute for Water Research Oslo Norway.,Department of Natural Sciences, Centre for Coastal Research (CCR) University of Agder Kristiansand Norway
| | - Sissel Jentoft
- Centre for Ecological and Evolutionary Synthesis Oslo Norway
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31
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Owens GL, Huang K, Todesco M, Rieseberg LH. Re-evaluating Homoploid Reticulate Evolution in Helianthus Sunflowers. Mol Biol Evol 2023; 40:6989481. [PMID: 36648104 PMCID: PMC9907532 DOI: 10.1093/molbev/msad013] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/03/2023] [Accepted: 01/11/2023] [Indexed: 01/18/2023] Open
Abstract
Sunflowers of the genus Helianthus are models for hybridization research and contain three of the best-studied examples of homoploid hybrid speciation. To understand a broader picture of hybridization within the annual sunflowers, we used whole-genome resequencing to conduct a phylogenomic analysis and test for gene flow between lineages. We find that all annual sunflower species tested have evidence of admixture, suggesting hybridization was common during the radiation of the genus. Support for the major species tree decreases with increasing recombination rate, consistent with hybridization and introgression contributing to discordant topologies. Admixture graphs found hybridization to be associated with the origins of the three putative hybrid species (Helianthus anomalus, Helianthus deserticola, and Helianthus paradoxus). However, the hybridization events are more ancient than suggested by previous work. Furthermore, H. anomalus and H. deserticola appear to have arisen from a single hybridization event involving an unexpected donor, rather than through multiple independent events as previously proposed. This means our results are consistent with, but not definitive proof of, two ancient independent homoploid hybrid speciation events in the genus. Using a broader data set that covers the whole Helianthus genus, including perennial species, we find that signals of introgression span the genus and beyond, suggesting highly divergent introgression and/or the sorting of ancient haplotypes. Thus, Helianthus can be viewed as a syngameon in which largely reproductively isolated species are linked together by occasional or frequent gene flow.
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Affiliation(s)
| | - Kaichi Huang
- Department of Botany and Beaty Biodiversity Center, University of British Columbia, Vancouver, BC, Canada
| | - Marco Todesco
- Department of Botany and Beaty Biodiversity Center, University of British Columbia, Vancouver, BC, Canada
| | - Loren H Rieseberg
- Department of Botany and Beaty Biodiversity Center, University of British Columbia, Vancouver, BC, Canada
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32
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Zhang W, Tan C, Hu H, Pan R, Xiao Y, Ouyang K, Zhou G, Jia Y, Zhang X, Hill CB, Wang P, Chapman B, Han Y, Xu L, Xu Y, Angessa T, Luo H, Westcott S, Sharma D, Nevo E, Barrero RA, Bellgard MI, He T, Tian X, Li C. Genome architecture and diverged selection shaping pattern of genomic differentiation in wild barley. PLANT BIOTECHNOLOGY JOURNAL 2023; 21:46-62. [PMID: 36054248 PMCID: PMC9829399 DOI: 10.1111/pbi.13917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/09/2022] [Accepted: 08/19/2022] [Indexed: 06/15/2023]
Abstract
Divergent selection of populations in contrasting environments leads to functional genomic divergence. However, the genomic architecture underlying heterogeneous genomic differentiation remains poorly understood. Here, we de novo assembled two high-quality wild barley (Hordeum spontaneum K. Koch) genomes and examined genomic differentiation and gene expression patterns under abiotic stress in two populations. These two populations had a shared ancestry and originated in close geographic proximity but experienced different selective pressures due to their contrasting micro-environments. We identified structural variants that may have played significant roles in affecting genes potentially associated with well-differentiated phenotypes such as flowering time and drought response between two wild barley genomes. Among them, a 29-bp insertion into the promoter region formed a cis-regulatory element in the HvWRKY45 gene, which may contribute to enhanced tolerance to drought. A single SNP mutation in the promoter region may influence HvCO5 expression and be putatively linked to local flowering time adaptation. We also revealed significant genomic differentiation between the two populations with ongoing gene flow. Our results indicate that SNPs and small SVs link to genetic differentiation at the gene level through local adaptation and are maintained through divergent selection. In contrast, large chromosome inversions may have shaped the heterogeneous pattern of genomic differentiation along the chromosomes by suppressing chromosome recombination and gene flow. Our research offers novel insights into the genomic basis underlying local adaptation and provides valuable resources for the genetic improvement of cultivated barley.
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Affiliation(s)
- Wenying Zhang
- Hubei Collaborative Innovation Centre for Grain IndustryYangtze UniversityJingzhouChina
| | - Cong Tan
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Haifei Hu
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Rui Pan
- Hubei Collaborative Innovation Centre for Grain IndustryYangtze UniversityJingzhouChina
| | - Yuhui Xiao
- Grandomics Biotechnology Co., LtdWuhanChina
| | - Kai Ouyang
- Grandomics Biotechnology Co., LtdWuhanChina
| | - Gaofeng Zhou
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Yong Jia
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Xiao‐Qi Zhang
- College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Camilla Beate Hill
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Penghao Wang
- College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Brett Chapman
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Yong Han
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
- Department of Primary Industries and Regional DevelopmentSouth PerthWestern AustraliaAustralia
| | - Le Xu
- Hubei Collaborative Innovation Centre for Grain IndustryYangtze UniversityJingzhouChina
| | - Yanhao Xu
- Hubei Collaborative Innovation Centre for Grain IndustryYangtze UniversityJingzhouChina
| | - Tefera Angessa
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Hao Luo
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Sharon Westcott
- Department of Primary Industries and Regional DevelopmentSouth PerthWestern AustraliaAustralia
| | - Darshan Sharma
- Department of Primary Industries and Regional DevelopmentSouth PerthWestern AustraliaAustralia
| | - Eviatar Nevo
- Institute of EvolutionUniversity of HaifaHaifaIsrael
| | - Roberto A. Barrero
- eResearch OfficeQueensland University of TechnologyBrisbaneQueenslandAustralia
| | - Matthew I. Bellgard
- eResearch OfficeQueensland University of TechnologyBrisbaneQueenslandAustralia
| | - Tianhua He
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
- College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
| | - Xiaohai Tian
- Hubei Collaborative Innovation Centre for Grain IndustryYangtze UniversityJingzhouChina
| | - Chengdao Li
- Western Crop Genetics Alliance, Future Food Institute, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
- College of Science, Health, Engineering and EducationMurdoch UniversityMurdochWestern AustraliaAustralia
- Department of Primary Industries and Regional DevelopmentSouth PerthWestern AustraliaAustralia
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33
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Harringmeyer OS, Hoekstra HE. Chromosomal inversion polymorphisms shape the genomic landscape of deer mice. Nat Ecol Evol 2022; 6:1965-1979. [PMID: 36253543 PMCID: PMC9715431 DOI: 10.1038/s41559-022-01890-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 08/17/2022] [Indexed: 12/15/2022]
Abstract
Chromosomal inversions are an important form of structural variation that can affect recombination, chromosome structure and fitness. However, because inversions can be challenging to detect, the prevalence and hence the significance of inversions segregating within species remains largely unknown, especially in natural populations of mammals. Here, by combining population-genomic and long-read sequencing analyses in a single, widespread species of deer mouse (Peromyscus maniculatus), we identified 21 polymorphic inversions that are large (1.5-43.8 Mb) and cause near-complete suppression of recombination when heterozygous (0-0.03 cM Mb-1). We found that inversion breakpoints frequently occur in centromeric and telomeric regions and are often flanked by long inverted repeats (0.5-50 kb), suggesting that they probably arose via ectopic recombination. By genotyping inversions in populations across the species' range, we found that the inversions are often widespread and do not harbour deleterious mutational loads, and many are likely to be maintained as polymorphisms by divergent selection. Comparisons of forest and prairie ecotypes of deer mice revealed 13 inversions that contribute to differentiation between populations, of which five exhibit significant associations with traits implicated in local adaptation. Taken together, these results show that inversion polymorphisms have a significant impact on recombination, genome structure and genetic diversity in deer mice and likely facilitate local adaptation across the widespread range of this species.
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Affiliation(s)
- Olivia S Harringmeyer
- Department of Organismic & Evolutionary Biology, Department of Molecular & Cellular Biology, Museum of Comparative Zoology and Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
| | - Hopi E Hoekstra
- Department of Organismic & Evolutionary Biology, Department of Molecular & Cellular Biology, Museum of Comparative Zoology and Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
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34
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Christie K, Fraser LS, Lowry DB. The strength of reproductive isolating barriers in seed plants: Insights from studies quantifying premating and postmating reproductive barriers over the past 15 years. Evolution 2022; 76:2228-2243. [PMID: 35838076 PMCID: PMC9796645 DOI: 10.1111/evo.14565] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 06/23/2022] [Accepted: 06/30/2022] [Indexed: 01/22/2023]
Abstract
Speciation is driven by the evolution of reproductive isolating barriers that reduce, and ultimately prevent, substantial gene flow between lineages. Despite its central role in evolutionary biology, the process can be difficult to study because it proceeds differently among groups and may occur over long timescales. Due to this complexity, we typically rely on generalizations of empirical data to describe and understand the process. Previous reviews of reproductive isolation (RI) in flowering plants have suggested that prezygotic or extrinsic barriers generally have a stronger effect on reducing gene flow compared to postzygotic or intrinsic barriers. Past conclusions have rested on relatively few empirical estimates of RI; however, RI data have become increasingly abundant over the past 15 years. We analyzed data from recent studies quantifying multiple pre- and postmating barriers in plants and compared the strengths of isolating barriers across 89 taxa pairs using standardized RI metrics. Individual prezygotic barriers were on average stronger than individual postzygotic barriers, and the total strength of prezygotic RI was approximately twice that of postzygotic RI. These findings corroborate that ecological divergence and extrinsic factors, as opposed to solely the accumulation of genetic incompatibilities, are important to speciation and the maintenance of species boundaries in plants. Despite an emphasis in the literature on asymmetric postmating and postzygotic RI, we found that prezygotic barriers acted equally asymmetrically. Overall, substantial variability in the strengths of 12 isolating barriers highlights the great diversity of mechanisms that contribute to plant diversification.
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Affiliation(s)
- Kyle Christie
- Department of Plant BiologyMichigan State UniversityEast LansingMichigan48824,Department of Biological SciencesNorthern Arizona UniversityFlagstaffArizona86011
| | - Linnea S. Fraser
- Department of Plant BiologyMichigan State UniversityEast LansingMichigan48824
| | - David B. Lowry
- Department of Plant BiologyMichigan State UniversityEast LansingMichigan48824
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35
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Shi Y, Homola JJ, Euclide PT, Isermann DA, Caroffino DC, McPhee MV, Larson WA. High‐density genomic data reveal fine‐scale population structure and pronounced islands of adaptive divergence in lake whitefish (
Coregonus clupeaformis
) from Lake Michigan. Evol Appl 2022; 15:1776-1791. [DOI: 10.1111/eva.13475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 08/12/2022] [Accepted: 08/14/2022] [Indexed: 11/28/2022] Open
Affiliation(s)
- Yue Shi
- College of Fisheries and Ocean Sciences University of Alaska Fairbanks Juneau AK USA
- Wisconsin Cooperative Fishery Research Unit College of Natural Resources, University of Wisconsin‐Stevens Point Stevens Point WI USA
| | - Jared J. Homola
- U.S. Geological Survey, Wisconsin Cooperative Fishery Research Unit College of Natural Resources, University of Wisconsin‐Stevens Point Stevens Point WI USA
| | - Peter T. Euclide
- Wisconsin Cooperative Fishery Research Unit College of Natural Resources, University of Wisconsin‐Stevens Point Stevens Point WI USA
| | - Daniel A. Isermann
- U.S. Geological Survey, Wisconsin Cooperative Fishery Research Unit College of Natural Resources, University of Wisconsin‐Stevens Point Stevens Point WI USA
| | - David C. Caroffino
- Michigan Department of Natural Resources, Charlevoix Research Station Charlevoix MI USA
| | - Megan V. McPhee
- College of Fisheries and Ocean Sciences University of Alaska Fairbanks Juneau AK USA
| | - Wesley A. Larson
- U.S. Geological Survey, Wisconsin Cooperative Fishery Research Unit College of Natural Resources, University of Wisconsin‐Stevens Point Stevens Point WI USA
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center, Auke Bay Laboratories Juneau AK USA
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36
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Cortés AJ, López-Hernández F, Blair MW. Genome–Environment Associations, an Innovative Tool for Studying Heritable Evolutionary Adaptation in Orphan Crops and Wild Relatives. Front Genet 2022; 13:910386. [PMID: 35991553 PMCID: PMC9389289 DOI: 10.3389/fgene.2022.910386] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 05/30/2022] [Indexed: 11/23/2022] Open
Abstract
Leveraging innovative tools to speed up prebreeding and discovery of genotypic sources of adaptation from landraces, crop wild relatives, and orphan crops is a key prerequisite to accelerate genetic gain of abiotic stress tolerance in annual crops such as legumes and cereals, many of which are still orphan species despite advances in major row crops. Here, we review a novel, interdisciplinary approach to combine ecological climate data with evolutionary genomics under the paradigm of a new field of study: genome–environment associations (GEAs). We first exemplify how GEA utilizes in situ georeferencing from genotypically characterized, gene bank accessions to pinpoint genomic signatures of natural selection. We later discuss the necessity to update the current GEA models to predict both regional- and local- or micro-habitat–based adaptation with mechanistic ecophysiological climate indices and cutting-edge GWAS-type genetic association models. Furthermore, to account for polygenic evolutionary adaptation, we encourage the community to start gathering genomic estimated adaptive values (GEAVs) for genomic prediction (GP) and multi-dimensional machine learning (ML) models. The latter two should ideally be weighted by de novo GWAS-based GEA estimates and optimized for a scalable marker subset. We end the review by envisioning avenues to make adaptation inferences more robust through the merging of high-resolution data sources, such as environmental remote sensing and summary statistics of the genomic site frequency spectrum, with the epigenetic molecular functionality responsible for plastic inheritance in the wild. Ultimately, we believe that coupling evolutionary adaptive predictions with innovations in ecological genomics such as GEA will help capture hidden genetic adaptations to abiotic stresses based on crop germplasm resources to assist responses to climate change. “I shall endeavor to find out how nature’s forces act upon one another, and in what manner the geographic environment exerts its influence on animals and plants. In short, I must find out about the harmony in nature” Alexander von Humboldt—Letter to Karl Freiesleben, June 1799.
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Affiliation(s)
- Andrés J. Cortés
- Corporacion Colombiana de Investigacion Agropecuaria AGROSAVIA, C.I. La Selva, Rionegro, Colombia
- *Correspondence: Andrés J. Cortés, ; Matthew W. Blair,
| | - Felipe López-Hernández
- Corporacion Colombiana de Investigacion Agropecuaria AGROSAVIA, C.I. La Selva, Rionegro, Colombia
| | - Matthew W. Blair
- Department of Agricultural & Environmental Sciences, Tennessee State University, Nashville, TN, United States
- *Correspondence: Andrés J. Cortés, ; Matthew W. Blair,
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37
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Westram AM, Faria R, Johannesson K, Butlin R, Barton N. Inversions and parallel evolution. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210203. [PMID: 35694747 PMCID: PMC9189493 DOI: 10.1098/rstb.2021.0203] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Local adaptation leads to differences between populations within a species. In many systems, similar environmental contrasts occur repeatedly, sometimes driving parallel phenotypic evolution. Understanding the genomic basis of local adaptation and parallel evolution is a major goal of evolutionary genomics. It is now known that by preventing the break-up of favourable combinations of alleles across multiple loci, genetic architectures that reduce recombination, like chromosomal inversions, can make an important contribution to local adaptation. However, little is known about whether inversions also contribute disproportionately to parallel evolution. Our aim here is to highlight this knowledge gap, to showcase existing studies, and to illustrate the differences between genomic architectures with and without inversions using simple models. We predict that by generating stronger effective selection, inversions can sometimes speed up the parallel adaptive process or enable parallel adaptation where it would be impossible otherwise, but this is highly dependent on the spatial setting. We highlight that further empirical work is needed, in particular to cover a broader taxonomic range and to understand the relative importance of inversions compared to genomic regions without inversions. This article is part of the theme issue ‘Genomic architecture of supergenes: causes and evolutionary consequences’.
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Affiliation(s)
- Anja M Westram
- ISTA (Institute of Science and Technology Austria), Klosterneuburg, Austria.,Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Rui Faria
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO, Laboratório Associado, Universidade do Porto, Vairão, Portugal.,BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal.,Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Sheffield, UK
| | | | - Roger Butlin
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Sheffield, UK.,Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Nick Barton
- ISTA (Institute of Science and Technology Austria), Klosterneuburg, Austria
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38
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Schaal SM, Haller BC, Lotterhos KE. Inversion invasions: when the genetic basis of local adaptation is concentrated within inversions in the face of gene flow. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210200. [PMID: 35694752 PMCID: PMC9189506 DOI: 10.1098/rstb.2021.0200] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Across many species where inversions have been implicated in local adaptation, genomes often evolve to contain multiple, large inversions that arise early in divergence. Why this occurs has yet to be resolved. To address this gap, we built forward-time simulations in which inversions have flexible characteristics and can invade a metapopulation undergoing spatially divergent selection for a highly polygenic trait. In our simulations, inversions typically arose early in divergence, captured standing genetic variation upon mutation, and then accumulated many small-effect loci over time. Under special conditions, inversions could also arise late in adaptation and capture locally adapted alleles. Polygenic inversions behaved similarly to a single supergene of large effect and were detectable by genome scans. Our results show that characteristics of adaptive inversions found in empirical studies (e.g. multiple large, old inversions that are FST outliers, sometimes overlapping with other inversions) are consistent with a highly polygenic architecture, and inversions do not need to contain any large-effect genes to play an important role in local adaptation. By combining a population and quantitative genetic framework, our results give a deeper understanding of the specific conditions needed for inversions to be involved in adaptation when the genetic architecture is polygenic. This article is part of the theme issue 'Genomic architecture of supergenes: causes and evolutionary consequences'.
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Affiliation(s)
- Sara M Schaal
- Department of Marine and Environmental Sciences, Northeastern University, Nahant, MA, USA
| | - Benjamin C Haller
- Department of Computational Biology, Cornell University, Ithaca, NY, USA
| | - Katie E Lotterhos
- Department of Marine and Environmental Sciences, Northeastern University, Nahant, MA, USA
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39
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Campbell MA, Joslin SEK, Goodbla AM, Willmes M, Hobbs JA, Lewis LS, Finger AJ. Polygenic discrimination of migratory phenotypes in an estuarine forage fish. G3 GENES|GENOMES|GENETICS 2022; 12:6595021. [PMID: 35640553 PMCID: PMC9339312 DOI: 10.1093/g3journal/jkac133] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/14/2022] [Indexed: 11/24/2022]
Abstract
Migration is a complex phenotypic trait with some species containing migratory and nonmigratory individuals. Such life history variation may be attributed in part to plasticity, epigenetics, or genetics. Although considered semianadromous, recent studies using otolith geochemistry have revealed life history variation within the critically endangered Delta Smelt. Broadly categorizable as migratory or freshwater residents, we examined Restriction site Associated DNA sequencing data to test for a relationship between genetic variation and migratory behaviors. As previously shown, we found no evidence for neutral population genetic structure within Delta Smelt; however, we found significant evidence for associations between genetic variants and life history phenotypes. Furthermore, discriminant analysis of principal components, hierarchical clustering, and machine learning resulted in accurate assignment of fish into the freshwater resident or migratory classes based on their genotypes. These results suggest the presence of adaptive genetic variants relating to life history variation within a panmictic population. Mechanisms that may lead to this observation are genotype dependent habitat choice and spatially variable selection, both of which could operate each generation and are not exclusive. Given that the population of cultured Delta Smelt are being used as a refugial population for conservation, as a supply for wild population supplementation, and currently represent the majority of all living individuals of this species, we recommend that the hatchery management strategy consider the frequencies of life history-associated alleles and how to maintain this important aspect of Delta Smelt biological variation while under captive propagation.
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Affiliation(s)
- Matthew A Campbell
- Genomic Variation Laboratory, Department of Animal Science, University of California, Davis , Davis, CA 95616, USA
| | - Shannon E K Joslin
- Genomic Variation Laboratory, Department of Animal Science, University of California, Davis , Davis, CA 95616, USA
| | - Alisha M Goodbla
- Genomic Variation Laboratory, Department of Animal Science, University of California, Davis , Davis, CA 95616, USA
| | - Malte Willmes
- Institute of Marine Sciences, UC Santa Cruz , Santa Cruz, CA 95064, USA
- National Marine Fisheries Service, Southwest Fisheries Science Center , Santa Cruz, CA 95064, USA
| | - James A Hobbs
- Otolith Geochemistry and Fish Ecology Lab, Department of Wildlife, Fish and Conservation Biology, University of California, Davis , Davis, CA 95616, USA
| | - Levi S Lewis
- Otolith Geochemistry and Fish Ecology Lab, Department of Wildlife, Fish and Conservation Biology, University of California, Davis , Davis, CA 95616, USA
| | - Amanda J Finger
- Genomic Variation Laboratory, Department of Animal Science, University of California, Davis , Davis, CA 95616, USA
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40
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Hager ER, Harringmeyer OS, Wooldridge TB, Theingi S, Gable JT, McFadden S, Neugeboren B, Turner KM, Jensen JD, Hoekstra HE. A chromosomal inversion contributes to divergence in multiple traits between deer mouse ecotypes. Science 2022; 377:399-405. [PMID: 35862520 DOI: 10.1126/science.abg0718] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
How locally adapted ecotypes are established and maintained within a species is a long-standing question in evolutionary biology. Using forest and prairie ecotypes of deer mice (Peromyscus maniculatus), we characterized the genetic basis of variation in two defining traits-tail length and coat color-and discovered a 41-megabase chromosomal inversion linked to both. The inversion frequency is 90% in the dark, long-tailed forest ecotype; decreases across a habitat transition; and is absent from the light, short-tailed prairie ecotype. We implicate divergent selection in maintaining the inversion at frequencies observed in the wild, despite high levels of gene flow, and explore fitness benefits that arise from suppressed recombination within the inversion. We uncover a key role for a large, previously uncharacterized inversion in the evolution and maintenance of classic mammalian ecotypes.
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Affiliation(s)
- Emily R Hager
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Olivia S Harringmeyer
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - T Brock Wooldridge
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Shunn Theingi
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Jacob T Gable
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Sade McFadden
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Beverly Neugeboren
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Kyle M Turner
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
| | - Jeffrey D Jensen
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Hopi E Hoekstra
- Department of Molecular and Cellular Biology, Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, and Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
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41
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Huang K, Ostevik KL, Elphinstone C, Todesco M, Bercovich N, Owens GL, Rieseberg LH. Mutation load in sunflower inversions is negatively correlated with inversion heterozygosity. Mol Biol Evol 2022; 39:6583099. [PMID: 35535689 PMCID: PMC9127631 DOI: 10.1093/molbev/msac101] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recombination is critical both for accelerating adaptation and purging deleterious mutations. Chromosomal inversions can act as recombination modifiers that suppress local recombination in heterozygotes and thus, under some conditions, are predicted to accumulate such mutations. In this study, we investigated patterns of recombination, transposable element abundance and coding sequence evolution across the genomes of 1,445 individuals from three sunflower species, as well as within nine inversions segregating within species. We also analyzed the effects of inversion genotypes on 87 phenotypic traits to test for overdominance. We found significant negative correlations of long terminal repeat retrotransposon abundance and deleterious mutations with recombination rates across the genome in all three species. However, we failed to detect an increase in these features in the inversions, except for a modest increase in the proportion of stop codon mutations in several very large or rare inversions. Consistent with this finding, there was little evidence of overdominance of inversions in phenotypes that may relate to fitness. On the other hand, significantly greater load was observed for inversions in populations polymorphic for a given inversion compared to populations monomorphic for one of the arrangements, suggesting that the local state of inversion polymorphism affects deleterious load. These seemingly contradictory results can be explained by the low frequency of inversion heterozygotes in wild sunflower populations, apparently due to divergent selection and associated geographic structure. Inversions contributing to local adaptation represent ideal recombination modifiers, acting to facilitate adaptive divergence with gene flow, while largely escaping the accumulation of deleterious mutations.
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Affiliation(s)
- Kaichi Huang
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Kate L Ostevik
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada.,Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, USA
| | - Cassandra Elphinstone
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Marco Todesco
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Natalia Bercovich
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Gregory L Owens
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada.,Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Loren H Rieseberg
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
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42
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Thorstensen MJ, Euclide PT, Jeffrey JD, Shi Y, Treberg JR, Watkinson DA, Enders EC, Larson WA, Kobayashi Y, Jeffries KM. A chromosomal inversion may facilitate adaptation despite periodic gene flow in a freshwater fish. Ecol Evol 2022; 12:e8898. [PMID: 35571758 PMCID: PMC9077824 DOI: 10.1002/ece3.8898] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/18/2022] [Accepted: 04/19/2022] [Indexed: 11/11/2022] Open
Affiliation(s)
- Matt J. Thorstensen
- Department of Biological Sciences University of Manitoba Winnipeg Manitoba Canada
| | - Peter T. Euclide
- Wisconsin Cooperative Fishery Research Unit College of Natural Resources U.S. Geological Survey University of Wisconsin‐Stevens Point Stevens Point Wisconsin USA
| | - Jennifer D. Jeffrey
- Department of Biological Sciences University of Manitoba Winnipeg Manitoba Canada
- Department of Biology Richardson College University of Winnipeg Winnipeg Manitoba Canada
| | - Yue Shi
- Wisconsin Cooperative Fishery Research Unit College of Natural Resources U.S. Geological Survey University of Wisconsin‐Stevens Point Stevens Point Wisconsin USA
- College of Fisheries and Ocean Sciences University of Alaska Fairbanks Juneau Alaska USA
| | - Jason R. Treberg
- Department of Biological Sciences University of Manitoba Winnipeg Manitoba Canada
| | | | - Eva C. Enders
- Freshwater Institute, Fisheries and Oceans Canada Winnipeg Manitoba Canada
| | - Wesley A. Larson
- Wisconsin Cooperative Fishery Research Unit College of Natural Resources U.S. Geological Survey University of Wisconsin‐Stevens Point Stevens Point Wisconsin USA
- National Oceanographic and Atmospheric Administration National Marine Fisheries Service Alaska Fisheries Science Center Auke Bay Laboratories Juneau Alaska USA
| | - Yasuhiro Kobayashi
- Department of Biological Sciences Fort Hays State University Hays Kansas USA
- Department of Biology The College of St. Scholastica Duluth Minnesota USA
| | - Ken M. Jeffries
- Department of Biological Sciences University of Manitoba Winnipeg Manitoba Canada
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43
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Kolis KM, Berg CS, Nelson TC, Fishman L. Population genomic consequences of life-history and mating system adaptation to a geothermal soil mosaic in yellow monkeyflowers. Evolution 2022; 76:765-781. [PMID: 35266558 DOI: 10.1111/evo.14469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 01/13/2022] [Accepted: 01/26/2022] [Indexed: 01/21/2023]
Abstract
Local selection can promote phenotypic divergence despite gene flow across habitat mosaics, but adaptation itself may generate substantial barriers to genetic exchange. In plants, life-history, phenology, and mating system divergence have been proposed to promote genetic differentiation in sympatry. In this study, we investigate phenotypic and genetic variation in Mimulus guttatus (yellow monkeyflowers) across a geothermal soil mosaic in Yellowstone National Park (YNP). Plants from thermal annual and nonthermal perennial habitats were heritably differentiated for life-history and mating system traits, consistent with local adaptation to the ephemeral thermal-soil growing season. However, genome-wide genetic variation primarily clustered plants by geographic region, with little variation sorting by habitat. The one exception was an extreme thermal population also isolated by a 200 m geographical gap of no intermediate habitat. Individual inbreeding coefficients (FIS ) were higher (and predicted by trait variation) in annual plants and annual pairs showed greater isolation by distance at local (<1 km) scales. Finally, YNP adaptation does not reuse a widespread inversion that underlies M. guttatus life-history ecotypes range-wide, suggesting a novel genetic mechanism. Overall, this work suggests that life-history and mating system adaptation strong enough to shape individual mating patterns does not necessarily generate incipient speciation without geographical barriers.
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Affiliation(s)
- Kory M Kolis
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812.,Current Address: O'Connor Center for the Rocky Mountain West, University of Montana, Missoula, MT, 59812
| | - Colette S Berg
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812
| | - Thomas C Nelson
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812.,Current Address: Embark Veterinary, Inc., Boston, Massachusetts, 02210
| | - Lila Fishman
- Division of Biological Sciences, University of Montana, Missoula, Montana, 59812
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44
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Nowling RJ, Fallas-Moya F, Sadovnik A, Emrich S, Aleck M, Leskiewicz D, Peters JG. Fast, low-memory detection and localization of large, polymorphic inversions from SNPs. PeerJ 2022; 10:e12831. [PMID: 35116204 PMCID: PMC8784018 DOI: 10.7717/peerj.12831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 01/04/2022] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Large (>1 Mb), polymorphic inversions have substantial impacts on population structure and maintenance of genotypes. These large inversions can be detected from single nucleotide polymorphism (SNP) data using unsupervised learning techniques like PCA. Construction and analysis of a feature matrix from millions of SNPs requires large amount of memory and limits the sizes of data sets that can be analyzed. METHODS We propose using feature hashing construct a feature matrix from a VCF file of SNPs for reducing memory usage. The matrix is constructed in a streaming fashion such that the entire VCF file is never loaded into memory at one time. RESULTS When evaluated on Anopheles mosquito and Drosophila fly data sets, our approach reduced memory usage by 97% with minimal reductions in accuracy for inversion detection and localization tasks. CONCLUSION With these changes, inversions in larger data sets can be analyzed easily and efficiently on common laptop and desktop computers. Our method is publicly available through our open-source inversion analysis software, Asaph.
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Affiliation(s)
- Ronald J. Nowling
- Electrical Engineering and Computer Science, Milwaukee School of Engineering, Milwaukee, Wisconsin, United States of America
| | - Fabian Fallas-Moya
- Electrical Engineering and Computer Science, University of Tennessee-Knoxville, Knoxville, Tennessee, United States
| | - Amir Sadovnik
- Electrical Engineering and Computer Science, University of Tennessee-Knoxville, Knoxville, Tennessee, United States
| | - Scott Emrich
- Electrical Engineering and Computer Science, University of Tennessee-Knoxville, Knoxville, Tennessee, United States
| | - Matthew Aleck
- Electrical Engineering and Computer Science, Milwaukee School of Engineering, Milwaukee, Wisconsin, United States of America
| | - Daniel Leskiewicz
- Electrical Engineering and Computer Science, Milwaukee School of Engineering, Milwaukee, Wisconsin, United States of America
| | - John G. Peters
- Electrical Engineering and Computer Science, Milwaukee School of Engineering, Milwaukee, Wisconsin, United States of America
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45
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Evolutionary genetics: Inversions — Do not quail but go big! Curr Biol 2022; 32:R76-R78. [DOI: 10.1016/j.cub.2021.12.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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46
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Rieseberg L, Warschefsky E, O'Boyle B, Taberlet P, Ortiz-Barrientos D, Kane NC, Sibbett B. Editorial 2022. Mol Ecol 2021; 31:1-30. [PMID: 34957606 DOI: 10.1111/mec.16328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 12/10/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Loren Rieseberg
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | - Pierre Taberlet
- Laboratoire d'Ecologie Alpine, CNRS UMR 5553, Université Univ. Grenoble Alpes, Grenoble Cedex 9, France
| | - Daniel Ortiz-Barrientos
- School of Biological Sciences, The University of Queenland, St. Lucia, Queensland, Australia
| | - Nolan C Kane
- University of Colorado at Boulder, Boulder, Colorado, USA
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47
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Shi Y, Bouska KL, McKinney GJ, Dokai W, Bartels A, McPhee MV, Larson WA. Gene flow influences the genomic architecture of local adaptation in six riverine fish species. Mol Ecol 2021; 32:1549-1566. [PMID: 34878685 DOI: 10.1111/mec.16317] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 11/15/2021] [Accepted: 12/01/2021] [Indexed: 11/30/2022]
Abstract
Understanding how gene flow influences adaptive divergence is important for predicting adaptive responses. Theoretical studies suggest that when gene flow is high, clustering of adaptive genes in fewer genomic regions would protect adaptive alleles from recombination and thus be selected for, but few studies have tested it with empirical data. Here, we used restriction site-associated sequencing to generate genomic data for six fish species with contrasting life histories from six reaches of the Upper Mississippi River System, USA. We used four differentiation-based outlier tests and three genotype-environment association analyses to define neutral single nucleotide polymorphisms (SNPs) and outlier SNPs that were putatively under selection. We then examined the distribution of outlier SNPs along the genome and investigated whether these SNPs were found in genomic islands of differentiation and inversions. We found that gene flow varied among species, and outlier SNPs were clustered more tightly in species with higher gene flow. The two species with the highest overall FST (0.0303-0.0720) and therefore lowest gene flow showed little evidence of clusters of outlier SNPs, with outlier SNPs in these species spreading uniformly across the genome. In contrast, nearly all outlier SNPs in the species with the lowest FST (0.0003) were found in a single large putative inversion. Two other species with intermediate gene flow (FST ~ 0.0025-0.0050) also showed clustered genomic architectures, with most islands of differentiation clustered on a few chromosomes. Our results provide important empirical evidence to support the hypothesis that increasingly clustered architecture of local adaptation is associated with high gene flow.
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Affiliation(s)
- Yue Shi
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, USA.,Wisconsin Cooperative Fishery Research Unit, College of Natural Resources, University of Wisconsin-Stevens Point, Stevens Point, Wisconsin, USA
| | - Kristen L Bouska
- U.S. Geological Survey, Upper Midwest Environmental Sciences Center, La Crosse, Wisconsin, USA
| | - Garrett J McKinney
- NRC Research Associateship Program, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, Washington, USA
| | - William Dokai
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, USA.,Wisconsin Cooperative Fishery Research Unit, College of Natural Resources, University of Wisconsin-Stevens Point, Stevens Point, Wisconsin, USA
| | - Andrew Bartels
- Long Term Resource Monitoring Program, Wisconsin Department of Natural Resources, La Crosse, Wisconsin, USA
| | - Megan V McPhee
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, USA
| | - Wesley A Larson
- National Oceanographic and Atmospheric Administration, Auke Bay Laboratories, National Marine Fisheries Service, Alaska Fisheries Science Center, Juneau, Alaska, USA.,U.S. Geological Survey, Wisconsin Cooperative Fishery Research Unit, College of Natural Resources, University of Wisconsin-Stevens Point, Stevens Point, Wisconsin, USA
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48
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Guzmán NV, Kemppainen P, Monti D, Castillo ERD, Rodriguero MS, Sánchez-Restrepo AF, Cigliano MM, Confalonieri VA. Stable inversion clines in a grasshopper species group despite complex geographical history. Mol Ecol 2021; 31:1196-1215. [PMID: 34862997 DOI: 10.1111/mec.16305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 11/24/2021] [Accepted: 11/29/2021] [Indexed: 11/27/2022]
Abstract
Chromosomal inversions are known to play roles in adaptation and differentiation in many species. They involve clusters of correlated genes (i.e., loci in linkage disequilibrium, LD) possibly associated with environmental variables. The grasshopper "species complex" Trimerotropis pallidipennis comprises several genetic lineages distributed from North to South America in arid and semi-arid high-altitude environments. The southernmost lineage, Trimerotropis sp., segregates for four to seven putative inversions that display clinal variation, possibly through adaptation to temperate environments. We analysed chromosomal, mitochondrial and genome-wide single nucleotide polymorphism data in 19 Trimerotropis sp. populations mainly distributed along two altitudinal gradients (MS and Ju). Populations across Argentina comprise two main chromosomally and genetically differentiated lineages: one distributed across the southernmost border of the "Andes Centrales," adding evidence for a differentiation hotspot in this area; and the other widely distributed in Argentina. Within the latter, network analytical approaches to LD found three clusters of correlated loci (LD-clusters), with inversion karyotypes explaining >79% of the genetic variation. Outlier loci associated with environmental variables mapped to two of these LD-clusters. Furthermore, despite the complex geographical history indicated by population genetic analyses, the clines in inversion karyotypes have remained stable for more than 20 generations, implicating their role in adaptation and differentiation within this lineage. We hypothesize that these clines could be the consequence of a coupling between extrinsic postzygotic barriers and spatially varying selection along environmental gradients resulting in a hybrid zone. These results provide a framework for future investigations about candidate genes implicated in rapid adaptation to new environments.
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Affiliation(s)
- Noelia V Guzmán
- Departamento de Ecología, Genética y Evolución, FCEyN, Universidad de Buenos Aires (UBA), IEGEBA (Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET)/UBA), Ciudad Universitaria, Buenos Aires, Argentina
| | - Petri Kemppainen
- Ecological Genetics Research Unit, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Daniela Monti
- Departamento de Ecología, Genética y Evolución, FCEyN, Universidad de Buenos Aires (UBA), IEGEBA (Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET)/UBA), Ciudad Universitaria, Buenos Aires, Argentina
| | - Elio R D Castillo
- Laboratorio de Genética Evolutiva "Dr. Claudio J. Bidau", FCEQyN, Universidad Nacional de Misiones (UNaM), Instituto de Biología Subtropical (IBS) (CONICET/UNaM), LQH, Posadas, Misiones, Argentina
| | - Marcela S Rodriguero
- Departamento de Ecología, Genética y Evolución, FCEyN, Universidad de Buenos Aires (UBA), IEGEBA (Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET)/UBA), Ciudad Universitaria, Buenos Aires, Argentina
| | - Andrés F Sánchez-Restrepo
- Departamento de Ecología, Genética y Evolución, FCEyN, Universidad de Buenos Aires (UBA), IEGEBA (Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET)/UBA), Ciudad Universitaria, Buenos Aires, Argentina.,Fundación para el Estudio de Especies Invasivas (FuEDEI), Hurlingham, Buenos Aires, Argentina
| | - Maria Marta Cigliano
- Museo de La Plata, Centro de Estudios Parasitológicos y de Vectores (CEPAVE- CONICET/UNLP), Universidad Nacional de la Plata, Buenos Aires, Argentina
| | - Viviana A Confalonieri
- Departamento de Ecología, Genética y Evolución, FCEyN, Universidad de Buenos Aires (UBA), IEGEBA (Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET)/UBA), Ciudad Universitaria, Buenos Aires, Argentina
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49
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Spies I, Drinan DP, Petrou EL, Spurr R, Tarpey C, Hartinger T, Larson W, Hauser L. Evidence for selection and spatially distinct patterns found in a putative zona pellucida gene in Pacific cod, and implications for management. Ecol Evol 2021; 11:16661-16679. [PMID: 34938464 PMCID: PMC8668774 DOI: 10.1002/ece3.8284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 10/08/2021] [Indexed: 11/11/2022] Open
Abstract
Genetic differentiation has been observed in marine species even when no obvious barriers to gene flow exist, and understanding such differentiation is essential for effective fisheries management. Highly differentiated outlier loci can provide information on how genetic variation might not only contribute to local adaptation but may also be affected by historical demographic events. A locus which aligned to a predicted zona pellucida sperm-binding protein 3 gene (ZP3) in Atlantic cod (Gadus morhua) was previously identified as the highest outlier based on F ST in a RADseq study of Pacific cod (Gadus macrocephalus) across the West Coast of North America. However, because of the limited length of the RAD sequence and restricted geographic area of sampling, no conclusion on the functional significance of the observed variation was possible. In other marine species, ZP3 is involved in reproductive isolation, local adaptation, and has neofunctionalized as an antifreeze gene, and so it may provide important insights in functional population structure of Pacific cod. Here, we sequenced a 544-bp region of ZP3 in 230 Pacific cod collected from throughout their geographic range. We observed striking patterns of spatial structuring of ZP3 haplotypes, with a sharp break near Kodiak, Alaska, USA where populations within ~200 km of each other are nearly fixed for different haplotypes, contrasting a pattern of isolation by distance at other genetic markers in this region (F ST = 0.003). Phylogenetic analysis of ZP3 haplotypes revealed that the more southern haplotypes appear to be ancestral, with the northern haplotype evolving more recently, potentially in response to a novel selective pressure as Pacific cod recolonized northern latitudes after glaciation. The sharp break in haplotype frequencies suggests strong selective pressures are operating on small spatial scales and illustrates that selection can create high divergence even in marine species with ample opportunities for gene flow.
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Affiliation(s)
- Ingrid Spies
- Resource Ecology and Fisheries Management DivisionAlaska Fisheries Science CenterSeattleWashingtonUSA
| | - Daniel P. Drinan
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Eleni L. Petrou
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Rory Spurr
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Carolyn Tarpey
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Theodore Hartinger
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
| | - Wes Larson
- Ted Stevens Marine Research InstituteAlaska Fisheries Science Center/Auke Bay LaboratoryJuneauAlaskaUSA
| | - Lorenz Hauser
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
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50
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Hale MC, Campbell MA, McKinney GJ. A candidate chromosome inversion in Arctic charr (Salvelinus alpinus) identified by population genetic analysis techniques. G3-GENES GENOMES GENETICS 2021; 11:6329827. [PMID: 34568922 PMCID: PMC8473973 DOI: 10.1093/g3journal/jkab267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 07/23/2021] [Indexed: 11/13/2022]
Abstract
The "genomics era" has allowed questions to be asked about genome organization and genome architecture of non-model species at a rate not previously seen. Analyses of these genome-wide datasets have documented many examples of novel structural variants (SVs) such as chromosomal inversions, copy number variants, and chromosomal translocations, many of which have been linked to adaptation. The salmonids are a taxonomic group with abundant genome-wide datasets due to their importance in aquaculture and fisheries. However, the number of documented SVs in salmonids is surprisingly low and is most likely due to removing loci in high linkage disequilibrium when analyzing structure and gene flow. Here we re-analyze RAD-seq data from several populations of Arctic charr (Salvelinus alpinus) and document a novel ∼1.2 MB SV at the distal end of LG12. This variant contains 15 protein-coding genes connected to a wide-range of functions including cell adhesion and signal transduction. Interestingly, we studied the frequency of this polymorphism in four disjointed populations of charr-one each from Nunavut, Newfoundland, Eastern Russia, and Scotland-and found evidence of the variant only in Nunavut, Canada, suggesting the polymorphism is novel and recently evolved.
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Affiliation(s)
- Matthew C Hale
- Department of Biology, Texas Christian University, Fort Worth, TX 76129, USA
| | - Matthew A Campbell
- Department of Animal Science, University of California Davis, Davis, CA 95616, USA.,University of Alaska Museum, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Garrett J McKinney
- National Research Council Research Associateship Program, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA 98112, USA
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