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Boudinot P, Novas S, Jouneau L, Mondot S, Lefranc MP, Grimholt U, Magadán S. Evolution of T cell receptor beta loci in salmonids. Front Immunol 2023; 14:1238321. [PMID: 37649482 PMCID: PMC10464911 DOI: 10.3389/fimmu.2023.1238321] [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: 06/11/2023] [Accepted: 07/17/2023] [Indexed: 09/01/2023] Open
Abstract
T-cell mediated immunity relies on a vast array of antigen specific T cell receptors (TR). Characterizing the structure of TR loci is essential to study the diversity and composition of T cell responses in vertebrate species. The lack of good-quality genome assemblies, and the difficulty to perform a reliably mapping of multiple highly similar TR sequences, have hindered the study of these loci in non-model organisms. High-quality genome assemblies are now available for the two main genera of Salmonids, Salmo and Oncorhynchus. We present here a full description and annotation of the TRB loci located on chromosomes 19 and 25 of rainbow trout (Oncorhynchus mykiss). To get insight about variations of the structure and composition of TRB locus across salmonids, we compared rainbow trout TRB loci with other salmonid species and confirmed that the basic structure of salmonid TRB locus is a double set of two TRBV-D-J-C loci in opposite orientation on two different chromosomes. Our data shed light on the evolution of TRB loci in Salmonids after their whole genome duplication (WGD). We established a coherent nomenclature of salmonid TRB loci based on comprehensive annotation. Our work provides a fundamental basis for monitoring salmonid T cell responses by TRB repertoire sequencing.
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Affiliation(s)
- Pierre Boudinot
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France
| | - Samuel Novas
- Immunology Laboratory, Research Center for Nanomaterials and Biomedicine (CINBIO), Universidade de Vigo, Vigo, Spain
| | - Luc Jouneau
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France
| | - Stanislas Mondot
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Marie-Paule Lefranc
- IMGT, The International ImMunoGeneTics Information System® (IMGT), Laboratoire d´ImmunoGénétique Moléculaire (LIGM), Institut de Génétique Humaine (IGH), Centre National de la Recherche Scientifique (CNRS), University of Montpellier, Montpellier, France
| | - Unni Grimholt
- Fish Health Research Section, Norwegian Veterinary Institute, Oslo, Norway
| | - Susana Magadán
- Immunology Laboratory, Research Center for Nanomaterials and Biomedicine (CINBIO), Universidade de Vigo, Vigo, Spain
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2
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Rondeau EB, Christensen KA, Johnson HA, Sakhrani D, Biagi CA, Wetklo M, Despins CA, Leggatt RA, Minkley DR, Withler RE, Beacham TD, Koop BF, Devlin RH. Insights from a chum salmon (Oncorhynchus keta) genome assembly regarding whole-genome duplication and nucleotide variation influencing gene function. G3 (BETHESDA, MD.) 2023; 13:jkad127. [PMID: 37293843 PMCID: PMC10411575 DOI: 10.1093/g3journal/jkad127] [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: 04/25/2023] [Revised: 05/30/2023] [Accepted: 06/04/2023] [Indexed: 06/10/2023]
Abstract
Chum salmon are ecologically important to Pacific Ocean ecosystems and commercially important to fisheries. To improve the genetic resources available for this species, we sequenced and assembled the genome of a male chum salmon using Oxford Nanopore read technology and the Flye genome assembly software (contig N50: ∼2 Mbp, complete BUSCOs: ∼98.1%). We also resequenced the genomes of 59 chum salmon from hatchery sources to better characterize the genome assembly and the diversity of nucleotide variants impacting phenotype variation. With genomic sequences from a doubled haploid individual, we were able to identify regions of the genome assembly that have been collapsed due to high sequence similarity between homeologous (duplicated) chromosomes. The homeologous chromosomes are relics of an ancient salmonid-specific genome duplication. These regions were enriched with genes whose functions are related to the immune system and responses to toxins. From analyzing nucleotide variant annotations of the resequenced genomes, we were also able to identify genes that have increased levels of variants thought to moderately impact gene function. Genes related to the immune system and the detection of chemical stimuli (olfaction) had increased levels of these variants based on a gene ontology enrichment analysis. The tandem organization of many of the enriched genes raises the question of why they have this organization.
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Affiliation(s)
- Eric B Rondeau
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8W 2Y2, Canada
- Fisheries and Oceans Canada, Pacific Biological Station, 3190 Hammond Bay Road, Nanaimo, BC V9T 6N7, Canada
| | - Kris A Christensen
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8W 2Y2, Canada
| | - Hollie A Johnson
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8W 2Y2, Canada
| | - Dionne Sakhrani
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada
| | - Carlo A Biagi
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada
| | - Mike Wetklo
- Fisheries and Oceans Canada, Pacific Biological Station, 3190 Hammond Bay Road, Nanaimo, BC V9T 6N7, Canada
| | - Cody A Despins
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8W 2Y2, Canada
| | - Rosalind A Leggatt
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada
| | - David R Minkley
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8W 2Y2, Canada
| | - Ruth E Withler
- Fisheries and Oceans Canada, Pacific Biological Station, 3190 Hammond Bay Road, Nanaimo, BC V9T 6N7, Canada
| | - Terry D Beacham
- Fisheries and Oceans Canada, Pacific Biological Station, 3190 Hammond Bay Road, Nanaimo, BC V9T 6N7, Canada
| | - Ben F Koop
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8W 2Y2, Canada
| | - Robert H Devlin
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada
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3
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Rougemont Q, Xuereb A, Dallaire X, Moore JS, Normandeau E, Perreault-Payette A, Bougas B, Rondeau EB, Withler RE, Van Doornik DM, Crane PA, Naish KA, Garza JC, Beacham TD, Koop BF, Bernatchez L. Long-distance migration is a major factor driving local adaptation at continental scale in Coho salmon. Mol Ecol 2023; 32:542-559. [PMID: 35000273 DOI: 10.1111/mec.16339] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 11/19/2021] [Accepted: 12/23/2021] [Indexed: 01/25/2023]
Abstract
Inferring the genomic basis of local adaptation is a long-standing goal of evolutionary biology. Beyond its fundamental evolutionary implications, such knowledge can guide conservation decisions for populations of conservation and management concern. Here, we investigated the genomic basis of local adaptation in the Coho salmon (Oncorhynchus kisutch) across its entire North American range. We hypothesized that extensive spatial variation in environmental conditions and the species' homing behaviour may promote the establishment of local adaptation. We genotyped 7829 individuals representing 217 sampling locations at more than 100,000 high-quality RADseq loci to investigate how recombination might affect the detection of loci putatively under selection and took advantage of the precise description of the demographic history of the species from our previous work to draw accurate population genomic inferences about local adaptation. The results indicated that genetic differentiation scans and genetic-environment association analyses were both significantly affected by variation in recombination rate as low recombination regions displayed an increased number of outliers. By taking these confounding factors into consideration, we revealed that migration distance was the primary selective factor driving local adaptation and partial parallel divergence among distant populations. Moreover, we identified several candidate single nucleotide polymorphisms associated with long-distance migration and altitude including a gene known to be involved in adaptation to altitude in other species. The evolutionary implications of our findings are discussed along with conservation applications.
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Affiliation(s)
- Quentin Rougemont
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada.,CEFE, Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier, Montpellier, France
| | - Amanda Xuereb
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Xavier Dallaire
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Jean-Sébastien Moore
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Eric Normandeau
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Alysse Perreault-Payette
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Bérénice Bougas
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Eric B Rondeau
- Department of Fisheries and Ocean, Pacific Biological Station, Nanaimo, British Columbia, Canada.,Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Ruth E Withler
- Department of Fisheries and Ocean, Pacific Biological Station, Nanaimo, British Columbia, Canada
| | - Donald M Van Doornik
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northwest Fisheries Science Center, Manchester Research Station, Port Orchard, Washington, USA
| | - Penelope A Crane
- Conservation Genetics Laboratory, U.S. Fish and Wildlife Service, Anchorage, Alaska, USA
| | - Kerry A Naish
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, USA
| | - John Carlos Garza
- Department of Ocean Sciences and Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California, USA
| | - Terry D Beacham
- Department of Fisheries and Ocean, Pacific Biological Station, Nanaimo, British Columbia, Canada
| | - Ben F Koop
- Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Louis Bernatchez
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
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4
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Cui Y, Fan B, Xu X, Sheng S, Xu Y, Wang X. A High-Density Genetic Map Enables Genome Synteny and QTL Mapping of Vegetative Growth and Leaf Traits in Gardenia. Front Genet 2022; 12:802738. [PMID: 35132310 PMCID: PMC8817757 DOI: 10.3389/fgene.2021.802738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022] Open
Abstract
The gardenia is a traditional medicinal horticultural plant in China, but its molecular genetic research has been largely hysteretic. Here, we constructed an F1 population with 200 true hybrid individuals. Using the genotyping-by-sequencing method, a high-density sex-average genetic map was generated that contained 4,249 SNPs with a total length of 1956.28 cM and an average genetic distance of 0.46 cM. We developed 17 SNP-based Kompetitive Allele-Specific PCR markers and found that 15 SNPs were successfully genotyped, of which 13 single-nucleotide polymorphism genotypings of 96 F1 individuals showed genotypes consistent with GBS-mined genotypes. A genomic collinearity analysis between gardenia and the Rubiaceae species Coffea arabica, Coffea canephora and Ophiorrhiza pumila showed the relativity strong conservation of LG11 with NC_039,919.1, HG974438.1 and Bliw01000011.1, respectively. Lastly, a quantitative trait loci analysis at three phenotyping time points (2019, 2020, and 2021) yielded 18 QTLs for growth-related traits and 31 QTLs for leaf-related traits, of which qBSBN7-1, qCD8 and qLNP2-1 could be repeatably detected. Five QTL regions (qCD8 and qSBD8, qBSBN7 and qSI7, qCD4-1 and qLLLS4, qLNP10 and qSLWS10-2, qSBD10 and qLLLS10) with potential pleiotropic effects were also observed. This study provides novel insight into molecular genetic research and could be helpful for further gene cloning and marker-assisted selection for early growth and development traits in the gardenia.
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Affiliation(s)
- Yang Cui
- Research Center for Traditional Chinese Medicine Resources and Ethnic Minority Medicine, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Baolian Fan
- Research Center for Traditional Chinese Medicine Resources and Ethnic Minority Medicine, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Xu Xu
- Research Center for Traditional Chinese Medicine Resources and Ethnic Minority Medicine, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Shasha Sheng
- Research Center for Traditional Chinese Medicine Resources and Ethnic Minority Medicine, Jiangxi University of Chinese Medicine, Nanchang, China
| | - Yuhui Xu
- Adsen Biotechnology Co., Ltd., Urumchi, China
| | - Xiaoyun Wang
- Research Center for Traditional Chinese Medicine Resources and Ethnic Minority Medicine, Jiangxi University of Chinese Medicine, Nanchang, China
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5
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6
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Smith SR, Normandeau E, Djambazian H, Nawarathna PM, Berube P, Muir AM, Ragoussis J, Penney CM, Scribner KT, Luikart G, Wilson CC, Bernatchez L. A chromosome-anchored genome assembly for Lake Trout (Salvelinus namaycush). Mol Ecol Resour 2021; 22:679-694. [PMID: 34351050 PMCID: PMC9291852 DOI: 10.1111/1755-0998.13483] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 07/25/2021] [Accepted: 07/28/2021] [Indexed: 01/23/2023]
Abstract
Here, we present an annotated, chromosome‐anchored, genome assembly for Lake Trout (Salvelinus namaycush) – a highly diverse salmonid species of notable conservation concern and an excellent model for research on adaptation and speciation. We leveraged Pacific Biosciences long‐read sequencing, paired‐end Illumina sequencing, proximity ligation (Hi‐C) sequencing, and a previously published linkage map to produce a highly contiguous assembly composed of 7378 contigs (contig N50 = 1.8 Mb) assigned to 4120 scaffolds (scaffold N50 = 44.975 Mb). Long read sequencing data were generated using DNA from a female double haploid individual. 84.7% of the genome was assigned to 42 chromosome‐sized scaffolds and 93.2% of Benchmarking Universal Single Copy Orthologues were recovered, putting this assembly on par with the best currently available salmonid genomes. Estimates of genome size based on k‐mer frequency analysis were highly similar to the total size of the finished genome, suggesting that the entirety of the genome was recovered. A mitochondrial genome assembly was also produced. Self‐versus‐self synteny analysis allowed us to identify homeologs resulting from the salmonid specific autotetraploid event (Ss4R) as well as regions exhibiting delayed rediploidization. Alignment with three other salmonid genomes and the Northern Pike (Esox lucius) genome also allowed us to identify homologous chromosomes in related taxa. We also generated multiple resources useful for future genomic research on Lake Trout, including a repeat library and a sex‐averaged recombination map. A novel RNA sequencing data set for liver tissue was also generated in order to produce a publicly available set of annotations for 49,668 genes and pseudogenes. Potential applications of these resources to population genetics and the conservation of native populations are discussed.
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Affiliation(s)
- Seth R Smith
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA.,Ecology, Evolution, and Behavior Program, Michigan State University, East Lansing, MI, USA
| | - Eric Normandeau
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Quebec, QC, Canada
| | - Haig Djambazian
- McGill Genome Centre, Department of Human Genetics, Montreal, QC, Canada
| | - Pubudu M Nawarathna
- Department of Human Genetics, Canadian Centre for Computational Genomics (C3G, McGill University, Montréal, QC, Canada
| | - Pierre Berube
- McGill Genome Centre, Department of Human Genetics, Montreal, QC, Canada
| | | | - Jiannis Ragoussis
- McGill Genome Centre, Department of Human Genetics, Montreal, QC, Canada
| | - Chantelle M Penney
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada
| | - Kim T Scribner
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA.,Ecology, Evolution, and Behavior Program, Michigan State University, East Lansing, MI, USA.,Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA
| | - Gordon Luikart
- Fish and Wildlife Genomics Group, University of Montana, Missoula, MT, USA.,Flathead Lake Biological Station, Division of Biological Sciences, University of Montana, Polson, MT, USA
| | - Chris C Wilson
- Aquatic Research and Monitoring Section, Ontario Ministry of Natural Resources and Forestry, Peterborough, ON, Canada
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Quebec, QC, Canada
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7
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Comparative Genomic Analyses and a Novel Linkage Map for Cisco ( Coregonus artedi) Provide Insights into Chromosomal Evolution and Rediploidization Across Salmonids. G3-GENES GENOMES GENETICS 2020; 10:2863-2878. [PMID: 32611547 PMCID: PMC7407451 DOI: 10.1534/g3.120.401497] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Whole-genome duplication (WGD) is hypothesized to be an important evolutionary mechanism that can facilitate adaptation and speciation. Genomes that exist in states of both diploidy and residual tetraploidy are of particular interest, as mechanisms that maintain the ploidy mosaic after WGD may provide important insights into evolutionary processes. The Salmonidae family exhibits residual tetraploidy, and this, combined with the evolutionary diversity formed after an ancestral autotetraploidization event, makes this group a useful study system. In this study, we generate a novel linkage map for cisco (Coregonus artedi), an economically and culturally important fish in North America and a member of the subfamily Coregoninae, which previously lacked a high-density haploid linkage map. We also conduct comparative genomic analyses to refine our understanding of chromosomal fusion/fission history across salmonids. To facilitate this comparative approach, we use the naming strategy of protokaryotype identifiers (PKs) to associate duplicated chromosomes to their putative ancestral state. The female linkage map for cisco contains 20,292 loci, 3,225 of which are likely within residually tetraploid regions. Comparative genomic analyses revealed that patterns of residual tetrasomy are generally conserved across species, although interspecific variation persists. To determine the broad-scale retention of residual tetrasomy across the salmonids, we analyze sequence similarity of currently available genomes and find evidence of residual tetrasomy in seven of the eight chromosomes that have been previously hypothesized to show this pattern. This interspecific variation in extent of rediploidization may have important implications for understanding salmonid evolutionary histories and informing future conservation efforts.
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8
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Campbell MA, Buser TJ, Alfaro ME, López JA. Addressing incomplete lineage sorting and paralogy in the inference of uncertain salmonid phylogenetic relationships. PeerJ 2020; 8:e9389. [PMID: 32685284 PMCID: PMC7337038 DOI: 10.7717/peerj.9389] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 05/28/2020] [Indexed: 12/14/2022] Open
Abstract
Recent and continued progress in the scale and sophistication of phylogenetic research has yielded substantial advances in knowledge of the tree of life; however, segments of that tree remain unresolved and continue to produce contradicting or unstable results. These poorly resolved relationships may be the product of methodological shortcomings or of an evolutionary history that did not generate the signal traits needed for its eventual reconstruction. Relationships within the euteleost fish family Salmonidae have proven challenging to resolve in molecular phylogenetics studies in part due to ancestral autopolyploidy contributing to conflicting gene trees. We examine a sequence capture dataset from salmonids and use alternative strategies to accommodate the effects of gene tree conflict based on aspects of salmonid genome history and the multispecies coalescent. We investigate in detail three uncertain relationships: (1) subfamily branching, (2) monophyly of Coregonus and (3) placement of Parahucho. Coregoninae and Thymallinae are resolved as sister taxa, although conflicting topologies are found across analytical strategies. We find inconsistent and generally low support for the monophyly of Coregonus, including in results of analyses with the most extensive dataset and complex model. The most consistent placement of Parahucho is as sister lineage of Salmo.
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Affiliation(s)
- Matthew A. Campbell
- University of Alaska Museum, University of Alaska—Fairbanks, Fairbanks, AK, USA
| | - Thaddaeus J. Buser
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, USA
| | - Michael E. Alfaro
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, USA
| | - J. Andrés López
- University of Alaska Museum, University of Alaska—Fairbanks, Fairbanks, AK, USA
- College of Fisheries and Ocean Sciences, University of Alaska—Fairbanks, Fairbanks, AK, USA
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9
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Mapping of Adaptive Traits Enabled by a High-Density Linkage Map for Lake Trout. G3-GENES GENOMES GENETICS 2020; 10:1929-1947. [PMID: 32284313 PMCID: PMC7263693 DOI: 10.1534/g3.120.401184] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Understanding the genomic basis of adaptative intraspecific phenotypic variation is a central goal in conservation genetics and evolutionary biology. Lake trout (Salvelinus namaycush) are an excellent species for addressing the genetic basis for adaptive variation because they express a striking degree of ecophenotypic variation across their range; however, necessary genomic resources are lacking. Here we utilize recently-developed analytical methods and sequencing technologies to (1) construct a high-density linkage and centromere map for lake trout, (2) identify loci underlying variation in traits that differentiate lake trout ecophenotypes and populations, (3) determine the location of the lake trout sex determination locus, and (4) identify chromosomal homologies between lake trout and other salmonids of varying divergence. The resulting linkage map contains 15,740 single nucleotide polymorphisms (SNPs) mapped to 42 linkage groups, likely representing the 42 lake trout chromosomes. Female and male linkage group lengths ranged from 43.07 to 134.64 centimorgans, and 1.97 to 92.87 centimorgans, respectively. We improved the map by determining coordinates for 41 of 42 centromeres, resulting in a map with 8 metacentric chromosomes and 34 acrocentric or telocentric chromosomes. We use the map to localize the sex determination locus and multiple quantitative trait loci (QTL) associated with intraspecific phenotypic divergence including traits related to growth and body condition, patterns of skin pigmentation, and two composite geomorphometric variables quantifying body shape. Two QTL for the presence of vermiculations and spots mapped with high certainty to an arm of linkage group Sna3, growth related traits mapped to two QTL on linkage groups Sna1 and Sna12, and putative body shape QTL were detected on six separate linkage groups. The sex determination locus was mapped to Sna4 with high confidence. Synteny analysis revealed that lake trout and congener Arctic char (Salvelinus alpinus) are likely differentiated by three or four chromosomal fissions, possibly one chromosomal fusion, and 6 or more large inversions. Combining centromere mapping information with putative inversion coordinates revealed that the majority of detected inversions differentiating lake trout from other salmonids are pericentric and located on acrocentric and telocentric linkage groups. Our results suggest that speciation and adaptive divergence within the genus Salvelinus may have been associated with multiple pericentric inversions occurring primarily on acrocentric and telocentric chromosomes. The linkage map presented here will be a critical resource for advancing conservation oriented genomic research on lake trout and exploring chromosomal evolution within and between salmonid species.
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10
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Pearse DE, Barson NJ, Nome T, Gao G, Campbell MA, Abadía-Cardoso A, Anderson EC, Rundio DE, Williams TH, Naish KA, Moen T, Liu S, Kent M, Moser M, Minkley DR, Rondeau EB, Brieuc MSO, Sandve SR, Miller MR, Cedillo L, Baruch K, Hernandez AG, Ben-Zvi G, Shem-Tov D, Barad O, Kuzishchin K, Garza JC, Lindley ST, Koop BF, Thorgaard GH, Palti Y, Lien S. Sex-dependent dominance maintains migration supergene in rainbow trout. Nat Ecol Evol 2019; 3:1731-1742. [DOI: 10.1038/s41559-019-1044-6] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 10/18/2019] [Indexed: 11/09/2022]
Abstract
AbstractMales and females often differ in their fitness optima for shared traits that have a shared genetic basis, leading to sexual conflict. Morphologically differentiated sex chromosomes can resolve this conflict and protect sexually antagonistic variation, but they accumulate deleterious mutations. However, how sexual conflict is resolved in species that lack differentiated sex chromosomes is largely unknown. Here we present a chromosome-anchored genome assembly for rainbow trout (Oncorhynchus mykiss) and characterize a 55-Mb double-inversion supergene that mediates sex-specific migratory tendency through sex-dependent dominance reversal, an alternative mechanism for resolving sexual conflict. The double inversion contains key photosensory, circadian rhythm, adiposity and sex-related genes and displays a latitudinal frequency cline, indicating environmentally dependent selection. Our results show sex-dependent dominance reversal across a large autosomal supergene, a mechanism for sexual conflict resolution capable of protecting sexually antagonistic variation while avoiding the homozygous lethality and deleterious mutations associated with typical heteromorphic sex chromosomes.
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11
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Discovery of a Novel MHC Class I Lineage in Teleost Fish which Shows Unprecedented Levels of Ectodomain Deterioration while Possessing an Impressive Cytoplasmic Tail Motif. Cells 2019; 8:cells8091056. [PMID: 31505831 PMCID: PMC6769792 DOI: 10.3390/cells8091056] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/02/2019] [Accepted: 09/04/2019] [Indexed: 12/25/2022] Open
Abstract
A unique new nonclassical MHC class I lineage was found in Teleostei (teleosts, modern bony fish, e.g., zebrafish) and Holostei (a group of primitive bony fish, e.g., spotted gar), which was designated “H” (from “hexa”) for being the sixth lineage discovered in teleosts. A high level of divergence of the teleost sequences explains why the lineage was not recognized previously. The spotted gar H molecule possesses the three MHC class I consensus extracellular domains α1, α2, and α3. However, throughout teleost H molecules, the α3 domain was lost and the α1 domains showed features of deterioration. In fishes of the two closely related teleost orders Characiformes (e.g., Mexican tetra) and Siluriformes (e.g., channel catfish), the H ectodomain deterioration proceeded furthest, with H molecules of some fishes apparently having lost the entire α1 or α2 domain plus additional stretches within the remaining other (α1 or α2) domain. Despite these dramatic ectodomain changes, teleost H sequences possess rather large, unique, well-conserved tyrosine-containing cytoplasmic tail motifs, which suggests an important role in intracellular signaling. To our knowledge, this is the first description of a group of MHC class I molecules in which, judging from the sequence conservation pattern, the cytoplasmic tail is expected to have a more important conserved function than the ectodomain.
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12
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Campbell MA, Hale MC, McKinney GJ, Nichols KM, Pearse DE. Long-Term Conservation of Ohnologs Through Partial Tetrasomy Following Whole-Genome Duplication in Salmonidae. G3 (BETHESDA, MD.) 2019; 9:2017-2028. [PMID: 31010824 PMCID: PMC6553544 DOI: 10.1534/g3.119.400070] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 04/18/2019] [Indexed: 01/01/2023]
Abstract
Whole-genome duplications (WGDs) have occurred repeatedly and broadly throughout the evolutionary history of eukaryotes. However, the effects of WGD on genome function and evolution remain unclear. The salmonid WGD that occurred approximately 88 million years ago presents an excellent opportunity for studying the effects of WGD as ∼10-15% of each salmonid genome still exhibits tetrasomic inheritance. Herein, we utilized the rainbow trout (Oncorhynchus mykiss) genome assembly and brain transcriptome data to examine the fate of gene pairs (ohnologs) following the salmonid whole-genome duplication. We find higher sequence identity between ohnologs located within known tetrasomic regions than between ohnologs found in disomic regions, and that tetrasomically inherited ohnologs showed greater similarity in patterns of gene expression and per ohnolog were lower expressed, than disomically inherited ohnologs. Enrichment testing for Gene Ontology terms identified 49 over-represented terms in tetrasomically inherited ohnologs compared to disomic ohnologs. However, why these ohnologs are retained as tetrasomic is difficult to answer. It could be that we have identified salmonid specific "dangerous duplicates", that is, genes that cannot take on new roles following WGD. Alternatively, there may be adaptive advantages for retaining genes as functional duplicates in tetrasomic regions, as presumably, movement of these genes into disomic regions would affect both their sequence identity and their gene expression patterns.
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Affiliation(s)
- Matthew A Campbell
- Fisheries Ecology Division, Southwest Fisheries Science Center, Santa Cruz, CA 95060
| | - Matthew C Hale
- Department of Biology, Texas Christian University, Fort Worth, TX 76129
| | - Garrett J McKinney
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA 98195, and
| | - Krista M Nichols
- Conservation Biology Division, Northwest Fisheries Science Center, Seattle, WA 98112
| | - Devon E Pearse
- Fisheries Ecology Division, Southwest Fisheries Science Center, Santa Cruz, CA 95060
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13
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Sutherland BJG, Prokkola JM, Audet C, Bernatchez L. Sex-Specific Co-expression Networks and Sex-Biased Gene Expression in the Salmonid Brook Charr Salvelinus fontinalis. G3 (BETHESDA, MD.) 2019; 9:955-968. [PMID: 30692150 PMCID: PMC6404618 DOI: 10.1534/g3.118.200910] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 01/21/2019] [Indexed: 12/31/2022]
Abstract
Networks of co-expressed genes produce complex phenotypes associated with functional novelty. Sex differences in gene expression levels or in the structure of gene co-expression networks can cause sexual dimorphism and may resolve sexually antagonistic selection. Here we used RNA-sequencing in the salmonid Brook Charr Salvelinus fontinalis to characterize sex-specific co-expression networks in the liver of 47 female and 53 male offspring. In both networks, modules were characterized for functional enrichment, hub gene identification, and associations with 15 growth, reproduction, and stress-related phenotypes. Modules were then evaluated for preservation in the opposite sex, and in the congener Arctic Charr Salvelinus alpinus Overall, more transcripts were assigned to a module in the female network than in the male network, which coincided with higher inter-individual gene expression and phenotype variation in the females. Most modules were preserved between sexes and species, including those involved in conserved cellular processes (e.g., translation, immune pathways). However, two sex-specific male modules were identified, and these may contribute to sexual dimorphism. To compare with the network analysis, differentially expressed transcripts were identified between the sexes, revealing a total of 16% of expressed transcripts as sex-biased. For both sexes, there was no overrepresentation of sex-biased genes or sex-specific modules on the putative sex chromosome. Sex-biased transcripts were also not overrepresented in sex-specific modules, and in fact highly male-biased transcripts were enriched in preserved modules. Comparative network analysis and differential expression analyses identified different aspects of sex differences in gene expression, and both provided new insights on the genes underlying sexual dimorphism in the salmonid Brook Charr.
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Affiliation(s)
- Ben J G Sutherland
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6, Canada
| | - Jenni M Prokkola
- Institute of Integrative Biology, University of Liverpool, L69 7ZB Liverpool, UK
| | - Céline Audet
- Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, Rimouski, QC G5L 3A1, Canada
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6, Canada
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14
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Marburger S, Alexandrou MA, Taggart JB, Creer S, Carvalho G, Oliveira C, Taylor MI. Whole genome duplication and transposable element proliferation drive genome expansion in Corydoradinae catfishes. Proc Biol Sci 2019; 285:rspb.2017.2732. [PMID: 29445022 PMCID: PMC5829208 DOI: 10.1098/rspb.2017.2732] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 01/25/2018] [Indexed: 01/12/2023] Open
Abstract
Genome size varies significantly across eukaryotic taxa and the largest changes are typically driven by macro-mutations such as whole genome duplications (WGDs) and proliferation of repetitive elements. These two processes may affect the evolutionary potential of lineages by increasing genetic variation and changing gene expression. Here, we elucidate the evolutionary history and mechanisms underpinning genome size variation in a species-rich group of Neotropical catfishes (Corydoradinae) with extreme variation in genome size—0.6 to 4.4 pg per haploid cell. First, genome size was quantified in 65 species and mapped onto a novel fossil-calibrated phylogeny. Two evolutionary shifts in genome size were identified across the tree—the first between 43 and 49 Ma (95% highest posterior density (HPD) 36.2–68.1 Ma) and the second at approximately 19 Ma (95% HPD 15.3–30.14 Ma). Second, restriction-site-associated DNA (RAD) sequencing was used to identify potential WGD events and quantify transposable element (TE) abundance in different lineages. Evidence of two lineage-scale WGDs was identified across the phylogeny, the first event occurring between 54 and 66 Ma (95% HPD 42.56–99.5 Ma) and the second at 20–30 Ma (95% HPD 15.3–45 Ma) based on haplotype numbers per contig and between 35 and 44 Ma (95% HPD 30.29–64.51 Ma) and 20–30 Ma (95% HPD 15.3–45 Ma) based on SNP read ratios. TE abundance increased considerably in parallel with genome size, with a single TE-family (TC1-IS630-Pogo) showing several increases across the Corydoradinae, with the most recent at 20–30 Ma (95% HPD 15.3–45 Ma) and an older event at 35–44 Ma (95% HPD 30.29–64.51 Ma). We identified signals congruent with two WGD duplication events, as well as an increase in TE abundance across different lineages, making the Corydoradinae an excellent model system to study the effects of WGD and TEs on genome and organismal evolution.
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Affiliation(s)
- Sarah Marburger
- Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences, Bangor University, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK.,School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - Markos A Alexandrou
- Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences, Bangor University, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK.,Wildlands Conservation Science, LLC PO Box 1846, Lompoc, CA 93438, USA
| | - John B Taggart
- Institute of Aquaculture, University of Stirling, Stirling FK9 4LA, UK
| | - Simon Creer
- Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences, Bangor University, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
| | - Gary Carvalho
- Molecular Ecology and Fisheries Genetics Laboratory, School of Biological Sciences, Bangor University, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
| | - Claudio Oliveira
- Departamento de Morfologia, Instituto de Biociências/UNESP, Rua Professor Doutor Antonio Celso Wagner Zanin, s/n°18618-689 Botucatu, São Paulo, Brazil
| | - Martin I Taylor
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
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15
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De-Kayne R, Feulner PGD. A European Whitefish Linkage Map and Its Implications for Understanding Genome-Wide Synteny Between Salmonids Following Whole Genome Duplication. G3 (BETHESDA, MD.) 2018; 8:3745-3755. [PMID: 30297382 PMCID: PMC6288842 DOI: 10.1534/g3.118.200552] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/03/2018] [Indexed: 12/11/2022]
Abstract
Genomic datasets continue to increase in number due to the ease of production for a wider selection of species including non-model organisms. For many of these species, especially those with large or polyploid genomes, highly contiguous and well-annotated genomes are still rare due to the complexity and cost involved in their assembly. As a result, a common starting point for genomic work in non-model species is the production of a linkage map. Dense linkage maps facilitate the analysis of genomic data in a variety of ways, from broad scale observations regarding genome structure e.g., chromosome number and type or sex-related structural differences, to fine scale patterns e.g., recombination rate variation and co-localization of differentiated regions. Here we present both sex-averaged and sex-specific linkage maps for Coregonus sp. "Albock", a member of the European whitefish lineage (C. lavaretus spp. complex), containing 5395 single nucleotide polymorphism (SNP) loci across 40 linkage groups to facilitate future investigation into the genomic basis of whitefish adaptation and speciation. The map was produced using restriction-site associated digestion (RAD) sequencing data from two wild-caught parents and 156 F1 offspring. We discuss the differences between our sex-averaged and sex-specific maps and identify genome-wide synteny between C. sp. "Albock" and Atlantic Salmon (Salmo salar), which have diverged following the salmonid-specific whole genome duplication. Our analysis confirms that many patterns of synteny observed between Atlantic Salmon and Oncorhynchus and Salvelinus species are also shared by members of the Coregoninae subfamily. We also show that regions known for their species-specific rediploidization history can pose challenges for synteny identification since these regions have diverged independently in each salmonid species following the salmonid-specific whole genome duplication. The European whitefish map provided here will enable future studies to understand the distribution of loci of interest, e.g., FST outliers, along the whitefish genome as well as assisting with the de novo assembly of a whitefish reference genome.
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Affiliation(s)
- Rishi De-Kayne
- Department of Fish Ecology and Evolution, Centre of Ecology, Evolution and Biogeochemistry, EAWAG Swiss Federal Institute of Aquatic Science and Technology, Switzerland
- Division of Aquatic Ecology and Evolution, Institute of Ecology and Evolution, University of Bern, Switzerland
| | - Philine G D Feulner
- Department of Fish Ecology and Evolution, Centre of Ecology, Evolution and Biogeochemistry, EAWAG Swiss Federal Institute of Aquatic Science and Technology, Switzerland
- Division of Aquatic Ecology and Evolution, Institute of Ecology and Evolution, University of Bern, Switzerland
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16
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Kodama M, Naish KA, Devlin RH. Influence of a growth hormone transgene on the genetic architecture of growth-related traits: A comparative analysis between transgenic and wild-type coho salmon. Evol Appl 2018; 11:1886-1900. [PMID: 30459836 PMCID: PMC6231474 DOI: 10.1111/eva.12692] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 07/26/2018] [Accepted: 07/28/2018] [Indexed: 12/20/2022] Open
Abstract
Genetic engineering has been increasingly applied to many commercially important plant and animal species, generating phenotypic changes that are not observed in natural populations and creating genetic interactions that have not experienced natural selection. The degree to and way in which such human-induced genetic variation interacts with the rest of the genome is currently largely unknown. Integrating such information into ecological and risk assessment frameworks is crucial to understand the potential effects of genetically modified organisms in natural environments. Here, we performed QTL mapping to investigate the genetic architecture of growth-related traits in nontransgenic (NT) and growth hormone transgenic (T) coho salmon with large changes in growth and related physiology, with the aim of identifying how an inserted transgene might influence the opportunity for selection. These fish shared the same parental genetic background, thus allowing us to determine whether the same or different loci influence these traits within the two groups. The use of over 1,700 loci, derived from restriction site-associated DNA sequencing, revealed that different genomic regions were linked with growth over time between the two groups. Additionally, the effect sizes of detected QTL appear to have been influenced by the transgene. Direct comparison of QTL between the T and NT fish during two size-matched periods identified little overlap in their location. Taken together, the results showed that the transgene altered the genetic basis of growth-related traits in this species. The study has important implications for effective conservation and management of wild populations experiencing introduction of transgenes. Evolutionary changes and their ecological consequences may occur at different rates and in different directions in NT versus T individuals in response to selection. Thus, assessments of phenotypic change, and hence ecological risk, should be determined periodically to evaluate whether initial estimates made with founder strains remain valid.
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Affiliation(s)
- Miyako Kodama
- Fisheries and Oceans CanadaWest VancouverBritish ColumbiaCanada
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattle, Washington
- Present address:
Natural History Museum of DenmarkUniversity of CopenhagenCopenhagenDenmark
- Present address:
Genome Research and Molecular BiomedicineDepartment of BiologyUniversity of CopenhagenCopenhagenDenmark
| | - Kerry A. Naish
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattle, Washington
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17
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Zhang HY, Zhao ZX, Xu J, Xu P, Bai QL, Yang SY, Jiang LK, Chen BH. Population genetic analysis of aquaculture salmonid populations in China using a 57K rainbow trout SNP array. PLoS One 2018; 13:e0202582. [PMID: 30118517 PMCID: PMC6097679 DOI: 10.1371/journal.pone.0202582] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 08/05/2018] [Indexed: 12/21/2022] Open
Abstract
Various salmonid species are cultivated in cold water aquaculture. However, due to limited genomic data resources, specific high-throughput genotyping tools are not available to many of the salmonid species. In this study, a 57K single nucleotide polymorphism (SNP) array for rainbow trout (Oncorhynchus mykiss) was utilized to detect polymorphisms in seven salmonid species, including Hucho taimen, Oncorhynchus masou, Salvelinus fontinalis, Brachymystax lenok, Salvelinus leucomaenis, O. kisutch, and O. mykiss. The number of polymorphic markers per population ranged from 3,844 (O. kisutch) to 53,734 (O. mykiss), indicating that the rainbow trout SNP array was applicable as a universal genotyping tool for other salmonid species. Among the six other salmonid populations from four genera, 28,882 SNPs were shared, whereas 525 SNPs were polymorphic in all four genera. The genetic diversity and population relationships of the seven salmonid species were studied by principal component analysis (PCA). The phylogenetic relationships among populations were analyzed using the maximum likelihood method, which indicated that the shared SNP markers provide reliable genomic information for population genetic analyses in common aquaculture salmonid fishes. Furthermore, this obtained genomic information may be applicable for population genetic evaluation, marker-assisted breeding, and propagative parent selection in fry production.
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Affiliation(s)
- Han-Yuan Zhang
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture, Beijing Key Laboratory of Fishery Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China
| | - Zi-Xia Zhao
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture, Beijing Key Laboratory of Fishery Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China
- * E-mail: (ZXZ); (PX)
| | - Jian Xu
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture, Beijing Key Laboratory of Fishery Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China
| | - Peng Xu
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture, Beijing Key Laboratory of Fishery Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China
- Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- * E-mail: (ZXZ); (PX)
| | - Qing-Li Bai
- Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin, China
| | - Shi-Yong Yang
- College of Animal Science and Technology, Sichuan Agricultural University, Yaan, China
| | - Li-Kun Jiang
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture, Beijing Key Laboratory of Fishery Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China
| | - Bao-Hua Chen
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture, Beijing Key Laboratory of Fishery Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China
- Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
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18
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Willoughby JR, Harder AM, Tennessen JA, Scribner KT, Christie MR. Rapid genetic adaptation to a novel environment despite a genome-wide reduction in genetic diversity. Mol Ecol 2018; 27:4041-4051. [PMID: 29802799 DOI: 10.1111/mec.14726] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/21/2018] [Accepted: 03/22/2018] [Indexed: 12/24/2022]
Affiliation(s)
- Janna R. Willoughby
- Department of Biological Sciences; Purdue University; West Lafayette Indiana
- Department of Forestry and Natural Resources; Purdue University; West Lafayette Indiana
| | - Avril M. Harder
- Department of Biological Sciences; Purdue University; West Lafayette Indiana
| | - Jacob A. Tennessen
- Department of Integrative Biology; Oregon State University; Corvallis Oregon
| | - Kim T. Scribner
- Department of Fisheries and Wildlife; Michigan State University; East Lansing Michigan
- Department of Integrative Biology; Michigan State University; East Lansing Michigan
| | - Mark R. Christie
- Department of Biological Sciences; Purdue University; West Lafayette Indiana
- Department of Forestry and Natural Resources; Purdue University; West Lafayette Indiana
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19
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Kodama M, Hard JJ, Naish KA. Mapping of quantitative trait loci for temporal growth and age at maturity in coho salmon: Evidence for genotype-by-sex interactions. Mar Genomics 2018; 38:33-44. [DOI: 10.1016/j.margen.2017.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 07/01/2017] [Accepted: 07/22/2017] [Indexed: 11/26/2022]
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20
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McKinney GJ, Waples RK, Pascal CE, Seeb LW, Seeb JE. Resolving allele dosage in duplicated loci using genotyping-by-sequencing data: A path forward for population genetic analysis. Mol Ecol Resour 2018; 18:570-579. [DOI: 10.1111/1755-0998.12763] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 01/18/2018] [Accepted: 01/19/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Garrett J. McKinney
- School of Aquatic and Fishery Sciences; University of Washington; Seattle WA USA
| | - Ryan K. Waples
- School of Aquatic and Fishery Sciences; University of Washington; Seattle WA USA
| | - Carita E. Pascal
- School of Aquatic and Fishery Sciences; University of Washington; Seattle WA USA
| | - Lisa W. Seeb
- School of Aquatic and Fishery Sciences; University of Washington; Seattle WA USA
| | - James E. Seeb
- School of Aquatic and Fishery Sciences; University of Washington; Seattle WA USA
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21
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Using Linkage Maps as a Tool To Determine Patterns of Chromosome Synteny in the Genus Salvelinus. G3-GENES GENOMES GENETICS 2017; 7:3821-3830. [PMID: 28963166 PMCID: PMC5677171 DOI: 10.1534/g3.117.300317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Next generation sequencing techniques have revolutionized the collection of genome and transcriptome data from nonmodel organisms. This manuscript details the application of restriction site-associated DNA sequencing (RADseq) to generate a marker-dense genetic map for Brook Trout (Salvelinus fontinalis). The consensus map was constructed from three full-sib families totaling 176 F1 individuals. The map consisted of 42 linkage groups with a total female map size of 2502.5 cM, and a total male map size of 1863.8 cM. Synteny was confirmed with Atlantic Salmon for 38 linkage groups, with Rainbow Trout for 37 linkage groups, Arctic Char for 36 linkage groups, and with a previously published Brook Trout linkage map for 39 linkage groups. Comparative mapping confirmed the presence of 8 metacentric and 34 acrocentric chromosomes in Brook Trout. Six metacentric chromosomes seem to be conserved with Arctic Char suggesting there have been at least two species-specific fusion and fission events within the genus Salvelinus. In addition, the sex marker (sdY; sexually dimorphic on the Y chromosome) was mapped to Brook Trout BC35, which is homologous with Atlantic Salmon Ssa09qa, Rainbow Trout Omy25, and Arctic Char AC04q. Ultimately, this linkage map will be a useful resource for studies on the genome organization of Salvelinus, and facilitates comparisons of the Salvelinus genome with Salmo and Oncorhynchus.
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22
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Sutherland BJG, Rico C, Audet C, Bernatchez L. Sex Chromosome Evolution, Heterochiasmy, and Physiological QTL in the Salmonid Brook Charr Salvelinus fontinalis. G3 (BETHESDA, MD.) 2017; 7:2749-2762. [PMID: 28626004 PMCID: PMC5555479 DOI: 10.1534/g3.117.040915] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 06/13/2017] [Indexed: 02/06/2023]
Abstract
Whole-genome duplication (WGD) can have large impacts on genome evolution, and much remains unknown about these impacts. This includes the mechanisms of coping with a duplicated sex determination system and whether this has an impact on increasing the diversity of sex determination mechanisms. Other impacts include sexual conflict, where alleles having different optimums in each sex can result in sequestration of genes into nonrecombining sex chromosomes. Sex chromosome development itself may involve sex-specific recombination rate (i.e., heterochiasmy), which is also poorly understood. The family Salmonidae is a model system for these phenomena, having undergone autotetraploidization and subsequent rediploidization in most of the genome at the base of the lineage. The salmonid master sex determining gene is known, and many species have nonhomologous sex chromosomes, putatively due to transposition of this gene. In this study, we identify the sex chromosome of Brook Charr Salvelinus fontinalis and compare sex chromosome identities across the lineage (eight species and four genera). Although nonhomology is frequent, homologous sex chromosomes and other consistencies are present in distantly related species, indicating probable convergence on specific sex and neo-sex chromosomes. We also characterize strong heterochiasmy with 2.7-fold more crossovers in maternal than paternal haplotypes with paternal crossovers biased to chromosome ends. When considering only rediploidized chromosomes, the overall heterochiasmy trend remains, although with only 1.9-fold more recombination in the female than the male. Y chromosome crossovers are restricted to a single end of the chromosome, and this chromosome contains a large interspecific inversion, although its status between males and females remains unknown. Finally, we identify quantitative trait loci (QTL) for 21 unique growth, reproductive, and stress-related phenotypes to improve knowledge of the genetic architecture of these traits important to aquaculture and evolution.
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Affiliation(s)
- Ben J G Sutherland
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec G1V 0A6, Canada
| | - Ciro Rico
- School of Marine Studies, Molecular Diagnostics Laboratory, University of the South Pacific, Suva, Fiji
- Department of Wetland Ecology, Estación Biológica de Doñana (EBD-CSIC), 41092 Sevilla, Spain
| | - Céline Audet
- Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, Quebec G5L 3A1, Canada
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec G1V 0A6, Canada
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23
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Limborg MT, Larson WA, Seeb LW, Seeb JE. Screening of duplicated loci reveals hidden divergence patterns in a complex salmonid genome. Mol Ecol 2017; 26:4509-4522. [DOI: 10.1111/mec.14201] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 04/03/2017] [Accepted: 04/10/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Morten T. Limborg
- School of Aquatic and Fishery Sciences University of Washington Seattle WA USA
| | - Wesley A. Larson
- School of Aquatic and Fishery Sciences University of Washington Seattle WA USA
| | - Lisa W. Seeb
- School of Aquatic and Fishery Sciences University of Washington Seattle WA USA
| | - James E. Seeb
- School of Aquatic and Fishery Sciences University of Washington Seattle WA USA
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24
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Waples RK, Seeb JE, Seeb LW. Congruent population structure across paralogous and nonparalogous loci in Salish Sea chum salmon (Oncorhynchus keta). Mol Ecol 2017; 26:4131-4144. [PMID: 28452089 DOI: 10.1111/mec.14163] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 04/01/2017] [Accepted: 04/10/2017] [Indexed: 12/19/2022]
Abstract
Whole-genome duplications are major evolutionary events with a lasting impact on genome structure. Duplication events complicate genetic analyses as paralogous sequences are difficult to distinguish; consequently, paralogs are often excluded from studies. The effects of an ancient whole-genome duplication (approximately 88 MYA) are still evident in salmonids through the persistence of numerous paralogous gene sequences and partial tetrasomic inheritance. We use restriction site-associated DNA sequencing on 10 collections of chum salmon from the Salish Sea in the USA and Canada to investigate genetic diversity and population structure in both tetrasomic and rediploidized regions of the genome. We use a pedigree and high-density linkage map to identify paralogous loci and to investigate genetic variation across the genome. By applying multivariate statistical methods, we show that it is possible to characterize paralogous loci and that they display similar patterns of population structure as the diploidized portion of the genome. We find genetic associations with the adaptively important trait of run-timing in both sets of loci. By including paralogous loci in genome scans, we can observe evolutionary signals in genomic regions that have routinely been excluded from population genetic studies in other polyploid-derived species.
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Affiliation(s)
- R K Waples
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - J E Seeb
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - L W Seeb
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
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25
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A Dense Brown Trout ( Salmo trutta) Linkage Map Reveals Recent Chromosomal Rearrangements in the Salmo Genus and the Impact of Selection on Linked Neutral Diversity. G3-GENES GENOMES GENETICS 2017; 7:1365-1376. [PMID: 28235829 PMCID: PMC5386884 DOI: 10.1534/g3.116.038497] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
High-density linkage maps are valuable tools for conservation and eco-evolutionary issues. In salmonids, a complex rediploidization process consecutive to an ancient whole genome duplication event makes linkage maps of prime importance for investigating the evolutionary history of chromosome rearrangements. Here, we developed a high-density consensus linkage map for the brown trout (Salmo trutta), a socioeconomically important species heavily impacted by human activities. A total of 3977 ddRAD markers were mapped and ordered in 40 linkage groups using sex- and lineage-averaged recombination distances obtained from two family crosses. Performing map comparison between S. trutta and its sister species, S. salar, revealed extensive chromosomal rearrangements. Strikingly, all of the fusion and fission events that occurred after the S. salar/S. trutta speciation happened in the Atlantic salmon branch, whereas the brown trout remained closer to the ancestral chromosome structure. Using the strongly conserved synteny within chromosome arms, we aligned the brown trout linkage map to the Atlantic salmon genome sequence to estimate the local recombination rate in S. trutta at 3721 loci. A significant positive correlation between recombination rate and within-population nucleotide diversity (π) was found, indicating that selection constrains variation at linked neutral sites in brown trout. This new high-density linkage map provides a useful genomic resource for future aquaculture, conservation, and eco-evolutionary studies in brown trout.
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A SNP Based Linkage Map of the Arctic Charr ( Salvelinus alpinus) Genome Provides Insights into the Diploidization Process After Whole Genome Duplication. G3-GENES GENOMES GENETICS 2017; 7:543-556. [PMID: 27986793 PMCID: PMC5295600 DOI: 10.1534/g3.116.038026] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Diploidization, which follows whole genome duplication events, does not occur evenly across the genome. In salmonid fishes, certain pairs of homeologous chromosomes preserve tetraploid loci in higher frequencies toward the telomeres due to residual tetrasomic inheritance. Research suggests this occurs only in homeologous pairs where one chromosome arm has undergone a fusion event. We present a linkage map for Arctic charr (Salvelinus alpinus), a salmonid species with relatively fewer chromosome fusions. Genotype by sequencing identified 19,418 SNPs, and a linkage map consisting of 4508 markers was constructed from a subset of high quality SNPs and microsatellite markers that were used to anchor the new map to previous versions. Both male- and female-specific linkage maps contained the expected number of 39 linkage groups. The chromosome type associated with each linkage group was determined, and 10 stable metacentric chromosomes were identified, along with a chromosome polymorphism involving the sex chromosome AC04. Two instances of a weak form of pseudolinkage were detected in the telomeric regions of homeologous chromosome arms in both female and male linkage maps. Chromosome arm homologies within the Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) genomes were determined. Paralogous sequence variants (PSVs) were identified, and their comparative BLASTn hit locations showed that duplicate markers exist in higher numbers on seven pairs of homeologous arms, previously identified as preserving tetrasomy in salmonid species. Homeologous arm pairs where neither arm has been part of a fusion event in Arctic charr had fewer PSVs, suggesting faster diploidization rates in these regions.
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Development of a 690 K SNP array in catfish and its application for genetic mapping and validation of the reference genome sequence. Sci Rep 2017; 7:40347. [PMID: 28079141 PMCID: PMC5228154 DOI: 10.1038/srep40347] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 12/05/2016] [Indexed: 02/02/2023] Open
Abstract
Single nucleotide polymorphisms (SNPs) are capable of providing the highest level of genome coverage for genomic and genetic analysis because of their abundance and relatively even distribution in the genome. Such a capacity, however, cannot be achieved without an efficient genotyping platform such as SNP arrays. In this work, we developed a high-density SNP array with 690,662 unique SNPs (herein 690 K array) that were relatively evenly distributed across the entire genome, and covered 98.6% of the reference genome sequence. Here we also report linkage mapping using the 690 K array, which allowed mapping of over 250,000 SNPs on the linkage map, the highest marker density among all the constructed linkage maps. These markers were mapped to 29 linkage groups (LGs) with 30,591 unique marker positions. This linkage map anchored 1,602 scaffolds of the reference genome sequence to LGs, accounting for over 97% of the total genome assembly. A total of 1,007 previously unmapped scaffolds were placed to LGs, allowing validation and in few instances correction of the reference genome sequence assembly. This linkage map should serve as a valuable resource for various genetic and genomic analyses, especially for GWAS and QTL mapping for genes associated with economically important traits.
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Wang L, Bai B, Liu P, Huang SQ, Wan ZY, Chua E, Ye B, Yue GH. Construction of high-resolution recombination maps in Asian seabass. BMC Genomics 2017; 18:63. [PMID: 28068919 PMCID: PMC5223582 DOI: 10.1186/s12864-016-3462-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 12/22/2016] [Indexed: 11/17/2022] Open
Abstract
Background A high-density genetic map is essential for de novo genome assembly, fine mapping QTL for important complex traits, comparative genomic studies and understanding the mechanisms of genome evolution. Although a number of genomic resources are available in Asian seabass (Lates calcarifer), a high-density linkage map is still lacking. To facilitate QTL mapping for marker-assisted selection and genome assembly, and to understand the genome-wide recombination rates, we constructed high density linkage maps using three families and genotyping by sequencing. Results A high-density consensus linkage map consisting of 8, 274 markers was constructed based on sex-averaged genetic maps. The genetic maps were then aligned and integrated with the current genome assembly of Asian seabass. More than 90% of the genome contig sequences were anchored onto the consensus genetic map. Evidence of assembly errors in the current genome assembly was identified. A fragment of up to 2.5 Mb belonging to LG14 was assembled into Chr15. The length of family-specific sex-averaged maps ranged from 1348.96 to 1624.65 cM. Female maps were slightly longer than male maps using common markers. Female-to-male ratios were highly variable both across chromosomes within each family and throughout three families for each chromosome. However, the distribution patterns of recombination along chromosomes were similar between sexes across the whole genome. The overall recombination rates were significantly correlated with genome-wide GC content and the correlations were revealed to be stronger in females than in males. Conclusions These high-density genetic maps provide not only essential tools for facilitating de novo genome assembly and comparative genomic studies in teleosts, but also critical resources for fine mapping QTL and genome-wide association mapping for economically important traits in Asian seabass. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3462-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Le Wang
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Bin Bai
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Peng Liu
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore.,Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Shu Qing Huang
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Zi Yi Wan
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Elaine Chua
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Baoqing Ye
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Gen Hua Yue
- Molecular Population Genetics and Breeding Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore. .,Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore. .,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore.
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Sutherland BJG, Gosselin T, Normandeau E, Lamothe M, Isabel N, Audet C, Bernatchez L. Salmonid Chromosome Evolution as Revealed by a Novel Method for Comparing RADseq Linkage Maps. Genome Biol Evol 2016; 8:3600-3617. [PMID: 28173098 PMCID: PMC5381510 DOI: 10.1093/gbe/evw262] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2016] [Indexed: 12/13/2022] Open
Abstract
Whole genome duplication (WGD) can provide material for evolutionary innovation. Family Salmonidae is ideal for studying the effects of WGD as the ancestral salmonid underwent WGD relatively recently, ∼65 Ma, then rediploidized and diversified. Extensive synteny between homologous chromosome arms occurs in extant salmonids, but each species has both conserved and unique chromosome arm fusions and fissions. Assembly of large, outbred eukaryotic genomes can be difficult, but structural rearrangements within such taxa can be investigated using linkage maps. RAD sequencing provides unprecedented ability to generate high-density linkage maps for nonmodel species, but can result in low numbers of homologous markers between species due to phylogenetic distance or differences in library preparation. Here, we generate a high-density linkage map (3,826 markers) for the Salvelinus genera (Brook Charr S. fontinalis), and then identify corresponding chromosome arms among the other available salmonid high-density linkage maps, including six species of Oncorhynchus, and one species for each of Salmo, Coregonus, and the nonduplicated sister group for the salmonids, Northern Pike Esox lucius for identifying post-duplicated homeologs. To facilitate this process, we developed MapComp to identify identical and proximate (i.e. nearby) markers between linkage maps using a reference genome of a related species as an intermediate, increasing the number of comparable markers between linkage maps by 5-fold. This enabled a characterization of the most likely history of retained chromosomal rearrangements post-WGD, and several conserved chromosomal inversions. Analyses of RADseq-based linkage maps from other taxa will also benefit from MapComp, available at: https://github.com/enormandeau/mapcomp/
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Affiliation(s)
- Ben J. G. Sutherland
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Thierry Gosselin
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Eric Normandeau
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Manuel Lamothe
- Centre de Foresterie des Laurentides, Ressources Naturelles Canada, Québec, QC, Canada
| | - Nathalie Isabel
- Centre de Foresterie des Laurentides, Ressources Naturelles Canada, Québec, QC, Canada
| | - Céline Audet
- Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, Rimouski, QC, Canada
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
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Leitwein M, Gagnaire PA, Desmarais E, Guendouz S, Rohmer M, Berrebi P, Guinand B. Genome-wide nucleotide diversity of hatchery-reared Atlantic and Mediterranean strains of brown trout Salmo trutta compared to wild Mediterranean populations. JOURNAL OF FISH BIOLOGY 2016; 89:2717-2734. [PMID: 27666575 DOI: 10.1111/jfb.13131] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 08/01/2016] [Indexed: 06/06/2023]
Abstract
A genome-wide assessment of diversity is provided for wild Mediterranean brown trout Salmo trutta populations from headwater tributaries of the Orb River and from Atlantic and Mediterranean hatchery-reared strains that have been used for stocking. Double-digest restriction-site-associated DNA sequencing (dd-RADseq) was performed and the efficiency of de novo and reference-mapping approaches to obtain individual genotypes was compared. Large numbers of single nucleotide polymorphism (SNP) markers with similar genome-wide distributions were discovered using both approaches (196 639 v. 121 016 SNPs, respectively), with c. 80% of the loci detected de novo being also found with reference mapping, using the Atlantic salmon Salmo salar genome as a reference. Lower mapping density but larger nucleotide diversity (π) was generally observed near extremities of linkage groups, consistent with regions of residual tetrasomic inheritance observed in salmonids. Genome-wide diversity estimates revealed reduced polymorphism in hatchery strains (π = 0·0040 and π = 0·0029 in Atlantic and Mediterranean strains, respectively) compared to wild populations (π = 0·0049), a pattern that was congruent with allelic richness estimated from microsatellite markers. Finally, pronounced heterozygote deficiency was found in hatchery strains (Atlantic FIS = 0·18; Mediterranean FIS = 0·42), indicating that stocking practices may affect the genetic diversity in wild populations. These new genomic resources will provide important tools to define better conservation strategies in S. trutta.
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Affiliation(s)
- M Leitwein
- UMR ISEM, Institut des Sciences de l'Evolution de Montpellier, Université de Montpellier, Place E. Bataillon - cc65, 34095, Montpellier Cedex 5, France
| | - P-A Gagnaire
- UMR ISEM, Institut des Sciences de l'Evolution de Montpellier, Université de Montpellier, Place E. Bataillon - cc65, 34095, Montpellier Cedex 5, France
- Station Biologique Marine, 2 Avenue des Chantiers, 34200, Sète, France
| | - E Desmarais
- UMR ISEM, Institut des Sciences de l'Evolution de Montpellier, Université de Montpellier, Place E. Bataillon - cc65, 34095, Montpellier Cedex 5, France
| | - S Guendouz
- MGX-Montpellier GenomiX, Institut de Génomique Fonctionnelle, 141 rue de Cardonille, 34094, Montpellier Cedex 5, France
| | - M Rohmer
- MGX-Montpellier GenomiX, Institut de Génomique Fonctionnelle, 141 rue de Cardonille, 34094, Montpellier Cedex 5, France
| | - P Berrebi
- UMR ISEM, Institut des Sciences de l'Evolution de Montpellier, Université de Montpellier, Place E. Bataillon - cc65, 34095, Montpellier Cedex 5, France
| | - B Guinand
- UMR ISEM, Institut des Sciences de l'Evolution de Montpellier, Université de Montpellier, Place E. Bataillon - cc65, 34095, Montpellier Cedex 5, France
- Département Biologie-Ecologie, Université de Montpellier, Place Eugène Bataillon, 34095, Montpellier Cedex 5, France
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McKinney GJ, Waples RK, Seeb LW, Seeb JE. Paralogs are revealed by proportion of heterozygotes and deviations in read ratios in genotyping-by-sequencing data from natural populations. Mol Ecol Resour 2016; 17:656-669. [DOI: 10.1111/1755-0998.12613] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 10/06/2016] [Accepted: 10/10/2016] [Indexed: 11/28/2022]
Affiliation(s)
- Garrett J. McKinney
- School of Aquatic and Fishery Sciences; University of Washington; 1122 NE Boat Street, Box 355020 Seattle WA 98195-5020 USA
| | - Ryan K. Waples
- School of Aquatic and Fishery Sciences; University of Washington; 1122 NE Boat Street, Box 355020 Seattle WA 98195-5020 USA
| | - Lisa W. Seeb
- School of Aquatic and Fishery Sciences; University of Washington; 1122 NE Boat Street, Box 355020 Seattle WA 98195-5020 USA
| | - James E. Seeb
- School of Aquatic and Fishery Sciences; University of Washington; 1122 NE Boat Street, Box 355020 Seattle WA 98195-5020 USA
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Benestan LM, Ferchaud A, Hohenlohe PA, Garner BA, Naylor GJP, Baums IB, Schwartz MK, Kelley JL, Luikart G. Conservation genomics of natural and managed populations: building a conceptual and practical framework. Mol Ecol 2016; 25:2967-77. [DOI: 10.1111/mec.13647] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 03/12/2016] [Accepted: 04/06/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Laura Marilyn Benestan
- Departement de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec G1V 0A6 Canada
| | - Anne‐Laure Ferchaud
- Departement de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec G1V 0A6 Canada
| | - Paul A. Hohenlohe
- Institute for Bioinformatics and Evolutionary Studies University of Idaho Moscow ID 83844 USA
| | - Brittany A. Garner
- Flathead Lake Biological Station Fish and Wildlife Genomic Group Division of Biological Science University of Montana Missoula MT 59812 USA
- Wildlife Program Fish and Wildlife Genomic Group College of Forestry and Conservation University of Montana Missoula MT 59812 USA
| | - Gavin J. P. Naylor
- Hollings Marine Lab College of Charleston and Medical University of South Carolina 331 Fort Johnson Rd. Charleston SC 29412 USA
| | - Iliana Brigitta Baums
- Department of Biology Pennsylvania State University 208 Mueller Lab University Park PA 1680 USA
| | - Michael K. Schwartz
- USDA Forest Service National Genomics Center for Wildlife and Fish Conservation 800 E. Beckwith Ave. Missoula MT 59801 USA
| | - Joanna L. Kelley
- School of Biological Sciences Washington State University Pullman WA 99164 USA
| | - Gordon Luikart
- Flathead Lake Biological Station Fish and Wildlife Genomic Group Division of Biological Science University of Montana Missoula MT 59812 USA
- Wildlife Program Fish and Wildlife Genomic Group College of Forestry and Conservation University of Montana Missoula MT 59812 USA
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Limborg MT, Seeb LW, Seeb JE. Sorting duplicated loci disentangles complexities of polyploid genomes masked by genotyping by sequencing. Mol Ecol 2016; 25:2117-29. [PMID: 26939067 DOI: 10.1111/mec.13601] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 02/19/2016] [Accepted: 02/24/2016] [Indexed: 01/04/2023]
Abstract
Many plants and animals of polyploid origin are currently enjoying a genomics explosion enabled by modern sequencing and genotyping technologies. However, routine filtering of duplicated loci in most studies using genotyping by sequencing introduces an unacceptable, but often overlooked, bias when detecting selection. Retained duplicates from ancient whole-genome duplications (WGDs) may be found throughout genomes, whereas retained duplicates from recent WGDs are concentrated at distal ends of some chromosome arms. Additionally, segmental duplicates can be found at distal ends or nearly anywhere in a genome. Evidence shows that these duplications facilitate adaptation through one of two pathways: neo-functionalization or increased gene expression. Filtering duplicates removes distal ends of some chromosomes, and distal ends are especially known to harbour adaptively important genes. Thus, filtering of duplicated loci impoverishes the interpretation of genomic data as signals from contiguous duplicated genes are ignored. We review existing strategies to genotype and map duplicated loci; we focus in detail on an overlooked strategy of using gynogenetic haploids (1N) as a part of new genotyping by sequencing studies. We provide guidelines on how to use this haploid strategy for studies on polyploid-origin vertebrates including how it can be used to screen duplicated loci in natural populations. We conclude by discussing areas of research that will benefit from better inclusion of polyploid loci; we particularly stress the sometimes overlooked fact that basing genomic studies on dense maps provides value added in the form of locating and annotating outlier loci or colocating outliers into islands of divergence.
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Affiliation(s)
- Morten T Limborg
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle, WA, 98195, USA.,National Institute of Aquatic Resources, Technical University of Denmark, Vejlsøvej 39, 8600 Silkeborg, Denmark
| | - Lisa W Seeb
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle, WA, 98195, USA
| | - James E Seeb
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle, WA, 98195, USA
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34
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The Atlantic salmon genome provides insights into rediploidization. Nature 2016; 533:200-5. [PMID: 27088604 PMCID: PMC8127823 DOI: 10.1038/nature17164] [Citation(s) in RCA: 640] [Impact Index Per Article: 80.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 01/26/2016] [Indexed: 01/24/2023]
Abstract
The whole-genome duplication 80 million years ago of the common ancestor of salmonids (salmonid-specific fourth vertebrate whole-genome duplication, Ss4R) provides unique opportunities to learn about the evolutionary fate of a duplicated vertebrate genome in 70 extant lineages. Here we present a high-quality genome assembly for Atlantic salmon (Salmo salar), and show that large genomic reorganizations, coinciding with bursts of transposon-mediated repeat expansions, were crucial for the post-Ss4R rediploidization process. Comparisons of duplicate gene expression patterns across a wide range of tissues with orthologous genes from a pre-Ss4R outgroup unexpectedly demonstrate far more instances of neofunctionalization than subfunctionalization. Surprisingly, we find that genes that were retained as duplicates after the teleost-specific whole-genome duplication 320 million years ago were not more likely to be retained after the Ss4R, and that the duplicate retention was not influenced to a great extent by the nature of the predicted protein interactions of the gene products. Finally, we demonstrate that the Atlantic salmon assembly can serve as a reference sequence for the study of other salmonids for a range of purposes. The genome sequence is presented for the Atlantic salmon (Salmo salar), providing information about a rediploidization following a salmonid-specific whole-genome duplication event that resulted in an autotetraploidization. William Davidson and colleagues report sequencing and assembly of the Atlantic salmon genome, which they demonstrate as a useful reference to also improve the genome assembly of other salmanoids. Their analyses provide insights into duplicate retention patterns across two rounds of whole-genome duplication that have occurred in this lineage.
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Wu H, He X, Gong H, Luo S, Li M, Chen J, Zhang C, Yu T, Huang W, Luo J. Genetic Linkage Map Construction and QTL Analysis of Two Interspecific Reproductive Isolation Traits in Sponge Gourd. FRONTIERS IN PLANT SCIENCE 2016; 7:980. [PMID: 27458467 PMCID: PMC4935800 DOI: 10.3389/fpls.2016.00980] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 06/21/2016] [Indexed: 05/22/2023]
Abstract
The hybrids between Luffa acutangula (L.) Roxb. and L.cylindrica (L.) Roem. have strong heterosis effects. However, some reproductive isolation traits hindered their normal hybridization and fructification, which was mainly caused by the flowering time and hybrid pollen sterility. In order to study the genetic basis of two interspecific reproductive isolation traits, we constructed a genetic linkage map using an F2 population derived from a cross between S1174 [L. acutangula (L.) Roxb.] and 93075 [L. cylindrica (L.) Roem.]. The map spans 1436.12 CentiMorgans (cM), with an average of 8.11 cM among markers, and consists of 177 EST-SSR markers distributed in 14 linkage groups (LG) with an average of 102.58 cM per LG. Meanwhile, we conducted colinearity analysis between the sequences of EST-SSR markers and the genomic sequences of cucumber, melon and watermelon. On the basis of genetic linkage map, we conducted QTL mapping of two reproductive isolation traits in sponge gourd, which were the flowering time and hybrid male sterility. Two putative QTLs associated with flowering time (FT) were both detected on LG 1. The accumulated contribution of these two QTLs explained 38.07% of the total phenotypic variance (PV), and each QTL explained 15.36 and 22.71% of the PV respectively. Four QTLs for pollen fertility (PF) were identified on LG 1 (qPF1.1 and qPF1.2), LG 3 (qPF3) and LG 7 (qPF7), respectively. The percentage of PF explained by these QTLs varied from 2.91 to 16.79%, and all together the four QTLs accounted for 39.98% of the total PV. Our newly developed EST-SSR markers and linkage map are very useful for gene mapping, comparative genomics and molecular marker-assisted breeding. These QTLs for interspecific reproductive isolation will also contribute to the cloning of genes relating to interspecific reproductive isolation and the utilization of interspecific heterosis in sponge gourd in further studies.
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Affiliation(s)
- Haibin Wu
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
- Guangdong Provincial Key Lab for New Technology Research on VegetablesGuangzhou, China
| | - Xiaoli He
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
| | - Hao Gong
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
| | - Shaobo Luo
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
- Guangdong Provincial Key Lab for New Technology Research on VegetablesGuangzhou, China
| | - Mingzhu Li
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
| | - Junqiu Chen
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
| | - Changyuan Zhang
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
| | - Ting Yu
- Agro-biological Gene Research Center, Guangdong Academy of Agricultural SciencesGuangzhou, China
| | - Wangping Huang
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
| | - Jianning Luo
- Vegetable Research Institute, Guangdong Academy of Agricultural ScienceGuangzhou, China
- *Correspondence: Jianning Luo
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Larson WA, McKinney GJ, Limborg MT, Everett MV, Seeb LW, Seeb JE. Identification of Multiple QTL Hotspots in Sockeye Salmon (Oncorhynchus nerka) Using Genotyping-by-Sequencing and a Dense Linkage Map. J Hered 2015; 107:122-33. [PMID: 26712859 DOI: 10.1093/jhered/esv099] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 11/18/2015] [Indexed: 02/01/2023] Open
Abstract
Understanding the genetic architecture of phenotypic traits can provide important information about the mechanisms and genomic regions involved in local adaptation and speciation. Here, we used genotyping-by-sequencing and a combination of previously published and newly generated data to construct sex-specific linkage maps for sockeye salmon (Oncorhynchus nerka). We then used the denser female linkage map to conduct quantitative trait locus (QTL) analysis for 4 phenotypic traits in 3 families. The female linkage map consisted of 6322 loci distributed across 29 linkage groups and was 4082 cM long, and the male map contained 2179 loci found on 28 linkage groups and was 2291 cM long. We found 26 QTL: 6 for thermotolerance, 5 for length, 9 for weight, and 6 for condition factor. QTL were distributed nonrandomly across the genome and were often found in hotspots containing multiple QTL for a variety of phenotypic traits. These hotspots may represent adaptively important regions and are excellent candidates for future research. Comparing our results with studies in other salmonids revealed several regions with overlapping QTL for the same phenotypic trait, indicating these regions may be adaptively important across multiple species. Altogether, our study demonstrates the utility of genomic data for investigating the genetic basis of important phenotypic traits. Additionally, the linkage map created here will enable future research on the genetic basis of phenotypic traits in salmon.
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Affiliation(s)
- Wesley A Larson
- From the School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle WA 98195-5020 (Larson, McKinney, Limborg, LW Seeb, and JE Seeb); Morten T. Limborg is now at the Centre for GeoGenetics, University of Copenhagen, 1350 Copenhagen K, Denmark; Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA, 98112 (Everett).
| | - Garrett J McKinney
- From the School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle WA 98195-5020 (Larson, McKinney, Limborg, LW Seeb, and JE Seeb); Morten T. Limborg is now at the Centre for GeoGenetics, University of Copenhagen, 1350 Copenhagen K, Denmark; Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA, 98112 (Everett)
| | - Morten T Limborg
- From the School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle WA 98195-5020 (Larson, McKinney, Limborg, LW Seeb, and JE Seeb); Morten T. Limborg is now at the Centre for GeoGenetics, University of Copenhagen, 1350 Copenhagen K, Denmark; Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA, 98112 (Everett)
| | - Meredith V Everett
- From the School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle WA 98195-5020 (Larson, McKinney, Limborg, LW Seeb, and JE Seeb); Morten T. Limborg is now at the Centre for GeoGenetics, University of Copenhagen, 1350 Copenhagen K, Denmark; Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA, 98112 (Everett)
| | - Lisa W Seeb
- From the School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle WA 98195-5020 (Larson, McKinney, Limborg, LW Seeb, and JE Seeb); Morten T. Limborg is now at the Centre for GeoGenetics, University of Copenhagen, 1350 Copenhagen K, Denmark; Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA, 98112 (Everett)
| | - James E Seeb
- From the School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle WA 98195-5020 (Larson, McKinney, Limborg, LW Seeb, and JE Seeb); Morten T. Limborg is now at the Centre for GeoGenetics, University of Copenhagen, 1350 Copenhagen K, Denmark; Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA, 98112 (Everett)
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Limborg MT, McKinney GJ, Seeb LW, Seeb JE. Recombination patterns reveal information about centromere location on linkage maps. Mol Ecol Resour 2015; 16:655-61. [PMID: 26561199 DOI: 10.1111/1755-0998.12484] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/29/2015] [Accepted: 11/04/2015] [Indexed: 12/22/2022]
Abstract
Linkage mapping is often used to identify genes associated with phenotypic traits and for aiding genome assemblies. Still, many emerging maps do not locate centromeres - an essential component of the genomic landscape. Here, we demonstrate that for genomes with strong chiasma interference, approximate centromere placement is possible by phasing the same data used to generate linkage maps. Assuming one obligate crossover per chromosome arm, information about centromere location can be revealed by tracking the accumulated recombination frequency along linkage groups, similar to half-tetrad analyses. We validate the method on a linkage map for sockeye salmon (Oncorhynchus nerka) with known centromeric regions. Further tests suggest that the method will work well in other salmonids and other eukaryotes. However, the method performed weakly when applied to a male linkage map (rainbow trout; O. mykiss) characterized by low and unevenly distributed recombination - a general feature of male meiosis in many species. Further, a high frequency of double crossovers along chromosome arms in barley reduced resolution for locating centromeric regions on most linkage groups. Despite these limitations, our method should work well for high-density maps in species with strong recombination interference and will enrich many existing and future mapping resources.
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Affiliation(s)
- Morten T Limborg
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle, WA, 98195, USA.,National Institute of Aquatic Resources, Technical University of Denmark, Vejlsøvej 39, 8600, Silkeborg, Denmark
| | - Garrett J McKinney
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle, WA, 98195, USA
| | - Lisa W Seeb
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle, WA, 98195, USA
| | - James E Seeb
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Box 355020, Seattle, WA, 98195, USA
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McKinney GJ, Seeb LW, Larson WA, Gomez‐Uchida D, Limborg MT, Brieuc MSO, Everett MV, Naish KA, Waples RK, Seeb JE. An integrated linkage map reveals candidate genes underlying adaptive variation in Chinook salmon (
Oncorhynchus tshawytscha
). Mol Ecol Resour 2015; 16:769-83. [DOI: 10.1111/1755-0998.12479] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/08/2015] [Accepted: 10/14/2015] [Indexed: 12/31/2022]
Affiliation(s)
- G. J. McKinney
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - L. W. Seeb
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - W. A. Larson
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - D. Gomez‐Uchida
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - M. T. Limborg
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - M. S. O. Brieuc
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - M. V. Everett
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - K. A. Naish
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - R. K. Waples
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
| | - J. E. Seeb
- School of Aquatic and Fishery Sciences University of Washington Seattle WA 98195‐5020 USA
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Limborg MT, Waples RK, Allendorf FW, Seeb JE. Linkage Mapping Reveals Strong Chiasma Interference in Sockeye Salmon: Implications for Interpreting Genomic Data. G3 (BETHESDA, MD.) 2015; 5:2463-73. [PMID: 26384769 PMCID: PMC4632065 DOI: 10.1534/g3.115.020222] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 09/14/2015] [Indexed: 01/15/2023]
Abstract
Meiotic recombination is fundamental for generating new genetic variation and for securing proper disjunction. Further, recombination plays an essential role during the rediploidization process of polyploid-origin genomes because crossovers between pairs of homeologous chromosomes retain duplicated regions. A better understanding of how recombination affects genome evolution is crucial for interpreting genomic data; unfortunately, current knowledge mainly originates from a few model species. Salmonid fishes provide a valuable system for studying the effects of recombination in nonmodel species. Salmonid females generally produce thousands of embryos, providing large families for conducting inheritance studies. Further, salmonid genomes are currently rediploidizing after a whole genome duplication and can serve as models for studying the role of homeologous crossovers on genome evolution. Here, we present a detailed interrogation of recombination patterns in sockeye salmon (Oncorhynchus nerka). First, we use RAD sequencing of haploid and diploid gynogenetic families to construct a dense linkage map that includes paralogous loci and location of centromeres. We find a nonrandom distribution of paralogs that mainly cluster in extended regions distally located on 11 different chromosomes, consistent with ongoing homeologous recombination in these regions. We also estimate the strength of interference across each chromosome; results reveal strong interference and crossovers are mostly limited to one per arm. Interference was further shown to continue across centromeres, but metacentric chromosomes generally had at least one crossover on each arm. We discuss the relevance of these findings for both mapping and population genomic studies.
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Affiliation(s)
- Morten T Limborg
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington 98195 National Institute of Aquatic Resources, Technical University of Denmark, Vejlsøvej 39, Silkeborg, Denmark
| | - Ryan K Waples
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington 98195
| | - Fred W Allendorf
- Division of Biological Sciences, University of Montana, Missoula, Montana 59812
| | - James E Seeb
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington 98195
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40
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Brieuc MSO, Ono K, Drinan DP, Naish KA. Integration of Random Forest with population-based outlier analyses provides insight on the genomic basis and evolution of run timing in Chinook salmon (Oncorhynchus tshawytscha). Mol Ecol 2015; 24:2729-46. [PMID: 25913096 DOI: 10.1111/mec.13211] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 04/15/2015] [Accepted: 04/21/2015] [Indexed: 01/11/2023]
Abstract
Anadromous Chinook salmon populations vary in the period of river entry at the initiation of adult freshwater migration, facilitating optimal arrival at natal spawning. Run timing is a polygenic trait that shows evidence of rapid parallel evolution in some lineages, signifying a key role for this phenotype in the ecological divergence between populations. Studying the genetic basis of local adaptation in quantitative traits is often impractical in wild populations. Therefore, we used a novel approach, Random Forest, to detect markers linked to run timing across 14 populations from contrasting environments in the Columbia River and Puget Sound, USA. The approach permits detection of loci of small effect on the phenotype. Divergence between populations at these loci was then examined using both principle component analysis and FST outlier analyses, to determine whether shared genetic changes resulted in similar phenotypes across different lineages. Sequencing of 9107 RAD markers in 414 individuals identified 33 predictor loci explaining 79.2% of trait variance. Discriminant analysis of principal components of the predictors revealed both shared and unique evolutionary pathways in the trait across different lineages, characterized by minor allele frequency changes. However, genome mapping of predictor loci also identified positional overlap with two genomic outlier regions, consistent with selection on loci of large effect. Therefore, the results suggest selective sweeps on few loci and minor changes in loci that were detected by this study. Use of a polygenic framework has provided initial insight into how divergence in a trait has occurred in the wild.
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Affiliation(s)
- Marine S O Brieuc
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, 98195-5020, USA
| | - Kotaro Ono
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, 98195-5020, USA
| | - Daniel P Drinan
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, 98195-5020, USA
| | - Kerry A Naish
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, 98195-5020, USA
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41
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Starks HA, Clemento AJ, Garza JC. Discovery and characterization of single nucleotide polymorphisms in coho salmon, Oncorhynchus kisutch. Mol Ecol Resour 2015; 16:277-87. [PMID: 25965351 DOI: 10.1111/1755-0998.12430] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 04/21/2015] [Accepted: 04/23/2015] [Indexed: 11/30/2022]
Abstract
Molecular population genetic analyses have become an integral part of ecological investigation and population monitoring for conservation and management. Microsatellites have been the molecular marker of choice for such applications over the last several decades, but single nucleotide polymorphism (SNP) markers are rapidly expanding beyond model organisms. Coho salmon (Oncorhynchus kisutch) is native to the north Pacific Ocean and its tributaries, where it is the focus of intensive fishery and conservation activities. As it is an anadromous species, coho salmon typically migrate across multiple jurisdictional boundaries, complicating management and requiring shared data collection methods. Here, we describe the discovery and validation of a suite of novel SNPs and associated genotyping assays which can be used in the genetic analyses of this species. These assays include 91 that are polymorphic in the species and one that discriminates it from a sister species, Chinook salmon. We demonstrate the utility of these SNPs for population assignment and phylogeographic analyses, and map them against the draft trout genome. The markers constitute a large majority of all SNP markers described for coho salmon and will enable both population- and pedigree-based analyses across the southern part of the species native range.
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Affiliation(s)
- Hilary A Starks
- Southwest Fisheries Science Center, National Marine Fisheries Service and University of California, Santa Cruz, 110 Shaffer Rd, Santa Cruz, CA, 95060, USA
| | - Anthony J Clemento
- Southwest Fisheries Science Center, National Marine Fisheries Service and University of California, Santa Cruz, 110 Shaffer Rd, Santa Cruz, CA, 95060, USA
| | - John Carlos Garza
- Southwest Fisheries Science Center, National Marine Fisheries Service and University of California, Santa Cruz, 110 Shaffer Rd, Santa Cruz, CA, 95060, USA
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Allendorf FW, Bassham S, Cresko WA, Limborg MT, Seeb LW, Seeb JE. Effects of crossovers between homeologs on inheritance and population genomics in polyploid-derived salmonid fishes. J Hered 2015; 106:217-27. [PMID: 25838153 DOI: 10.1093/jhered/esv015] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Accepted: 02/19/2015] [Indexed: 01/24/2023] Open
Abstract
A whole genome duplication occurred in the ancestor of all salmonid fishes some 50-100 million years ago. Early inheritance studies with allozymes indicated that loci in the salmonid genome are inherited disomically in females. However, some pairs of duplicated loci showed patterns of inheritance in males indicating pairing and recombination between homeologous chromosomes. Nearly 20% of loci in the salmonid genome are duplicated and share the same alleles (isoloci), apparently due to homeologous recombination. Half-tetrad analysis revealed that isoloci tend to be telomeric. These results suggested that residual tetrasomic inheritance of isoloci results from homeologous recombination near chromosome ends and that continued disomic inheritance resulted from homologous pairing of centromeric regions. Many current genetic maps of salmonids are based on single nucleotide polymorphisms and microsatellites that are no longer duplicated. Therefore, long sections of chromosomes on these maps are poorly represented, especially telomeric regions. In addition, preferential multivalent pairing of homeologs from the same species in F1 hybrids results in an excess of nonparental gametes (so-called pseudolinkage). We consider how not including duplicated loci has affected our understanding of population and evolutionary genetics of salmonids, and we discuss how incorporating these loci will benefit our understanding of population genomics.
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Affiliation(s)
- Fred W Allendorf
- From the University of Montana, Division of Biological Sciences, Missoula, MT 59812 (Allendorf); University of Oregon, Institute of Ecology and Evolution, Eugene, OR (Bassham and Cresko); and University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA (Limborg, L. Seeb, and J. Seeb).
| | - Susan Bassham
- From the University of Montana, Division of Biological Sciences, Missoula, MT 59812 (Allendorf); University of Oregon, Institute of Ecology and Evolution, Eugene, OR (Bassham and Cresko); and University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA (Limborg, L. Seeb, and J. Seeb)
| | - William A Cresko
- From the University of Montana, Division of Biological Sciences, Missoula, MT 59812 (Allendorf); University of Oregon, Institute of Ecology and Evolution, Eugene, OR (Bassham and Cresko); and University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA (Limborg, L. Seeb, and J. Seeb)
| | - Morten T Limborg
- From the University of Montana, Division of Biological Sciences, Missoula, MT 59812 (Allendorf); University of Oregon, Institute of Ecology and Evolution, Eugene, OR (Bassham and Cresko); and University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA (Limborg, L. Seeb, and J. Seeb)
| | - Lisa W Seeb
- From the University of Montana, Division of Biological Sciences, Missoula, MT 59812 (Allendorf); University of Oregon, Institute of Ecology and Evolution, Eugene, OR (Bassham and Cresko); and University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA (Limborg, L. Seeb, and J. Seeb)
| | - James E Seeb
- From the University of Montana, Division of Biological Sciences, Missoula, MT 59812 (Allendorf); University of Oregon, Institute of Ecology and Evolution, Eugene, OR (Bassham and Cresko); and University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA (Limborg, L. Seeb, and J. Seeb)
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Waples RK, Seeb LW, Seeb JE. Linkage mapping with paralogs exposes regions of residual tetrasomic inheritance in chum salmon (Oncorhynchus keta). Mol Ecol Resour 2015; 16:17-28. [DOI: 10.1111/1755-0998.12394] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 02/13/2015] [Accepted: 02/20/2015] [Indexed: 11/27/2022]
Affiliation(s)
- R. K. Waples
- School of Aquatic and Fishery Sciences; University of Washington; 1122 NE Boat Street Box 355020 Seattle Washington 98195 USA
| | - L. W. Seeb
- School of Aquatic and Fishery Sciences; University of Washington; 1122 NE Boat Street Box 355020 Seattle Washington 98195 USA
| | - J. E. Seeb
- School of Aquatic and Fishery Sciences; University of Washington; 1122 NE Boat Street Box 355020 Seattle Washington 98195 USA
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