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Oppong-Danquah E, Blümel M, Tasdemir D. Metabolomics and Microbiomics Insights into Differential Surface Fouling of Three Macroalgal Species of Fucus (Fucales, Phaeophyceae) That Co-Exist in the German Baltic Sea. Mar Drugs 2023; 21:595. [PMID: 37999420 PMCID: PMC10672516 DOI: 10.3390/md21110595] [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: 10/20/2023] [Revised: 11/15/2023] [Accepted: 11/15/2023] [Indexed: 11/25/2023] Open
Abstract
The brown algal genus Fucus provides essential ecosystem services crucial for marine environments. Macroalgae (seaweeds) release dissolved organic matter, hence, are under strong settlement pressure from micro- and macrofoulers. Seaweeds are able to control surface epibionts directly by releasing antimicrobial compounds onto their surfaces, and indirectly by recruiting beneficial microorganisms that produce antimicrobial/antifouling metabolites. In the Kiel Fjord, in the German Baltic Sea, three distinct Fucus species coexist: F. vesiculosus, F. serratus, and F. distichus subsp. evanescens. Despite sharing the same habitat, they show varying fouling levels; F. distichus subsp. evanescens is the least fouled, while F. vesiculosus is the most fouled. The present study explored the surface metabolomes and epiphytic microbiota of these three Fucus spp., aiming to uncover the factors that contribute to the differences in the fouling intensity on their surfaces. Towards this aim, algal surface metabolomes were analyzed using comparative untargeted LC-MS/MS-based metabolomics, to identify the marker metabolites influencing surface fouling. Their epiphytic microbial communities were also comparatively characterized using high-throughput amplicon sequencing, to pinpoint the differences in the surface microbiomes of the algae. Our results show that the surface of the least fouling species, F. distichus subsp. evanescens, is enriched with bioactive compounds, such as betaine lipids MGTA, 4-pyridoxic acid, and ulvaline, which are absent from the other species. Additionally, it exhibits a high abundance of the fungal genera Mucor and Alternaria, along with the bacterial genus Yoonia-Loktanella. These taxa are known for producing antimicrobial/antifouling compounds, suggesting their potential role in the observed fouling resistance on the surface of the F. distichus subsp. evanescens compared to F. serratus and F. vesiculosus. These findings provide valuable clues on the differential surface fouling intensity of Fucus spp., and their importance in marine chemical defense and fouling dynamics.
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Affiliation(s)
- Ernest Oppong-Danquah
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstrasse 1–3, 24148 Kiel, Germany; (E.O.-D.); (M.B.)
| | - Martina Blümel
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstrasse 1–3, 24148 Kiel, Germany; (E.O.-D.); (M.B.)
| | - Deniz Tasdemir
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstrasse 1–3, 24148 Kiel, Germany; (E.O.-D.); (M.B.)
- Faculty of Mathematics and Natural Science, Kiel University, Christian-Albrechts-Platz 4, 24118 Kiel, Germany
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2
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Hatchett WJ, Jueterbock AO, Kopp M, Coyer JA, Coelho SM, Hoarau G, Lipinska AP. Evolutionary dynamics of sex-biased gene expression in a young XY system: insights from the brown alga genus Fucus. THE NEW PHYTOLOGIST 2023; 238:422-437. [PMID: 36597732 DOI: 10.1111/nph.18710] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
Sex-biased gene expression is considered to be an underlying cause of sexually dimorphic traits. Although the nature and degree of sex-biased expression have been well documented in several animal and plant systems, far less is known about the evolution of sex-biased genes in more distant eukaryotic groups. Here, we investigate sex-biased gene expression in two brown algal dioecious species, Fucus serratus and Fucus vesiculosus, where male heterogamety (XX/XY) has recently emerged. We find that in contrast to evolutionary distant plant and animal lineages, male-biased genes do not experience high turnover rates, but instead reveal remarkable conservation of bias and expression levels between the two species, suggesting their importance in sexual differentiation. Genes with consistent male bias were enriched in functions related to gamete production, along with sperm competition and include three flagellar proteins under positive selection. We present one of the first reports, outside of the animal kingdom, showing that male-biased genes display accelerated rates of coding sequence evolution compared with female-biased or unbiased genes. Our results imply that evolutionary forces affect male and female sex-biased genes differently on structural and regulatory levels, resulting in unique properties of differentially expressed transcripts during reproductive development in Fucus algae.
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Affiliation(s)
- William J Hatchett
- Faculty of Biosciences and Aquaculture, Nord University, 8026, Bodø, Norway
| | | | - Martina Kopp
- Faculty of Biosciences and Aquaculture, Nord University, 8026, Bodø, Norway
| | - James A Coyer
- Shoals Marine Laboratory, University of New Hampshire, Durham, NH, 03824, USA
| | - Susana M Coelho
- CNRS, Algal Genetics Group, UMR 8227, Integrative Biology of Marine Models, Sorbonne Université, Station Biologique de Roscoff, 29680, Roscoff, France
- Department of Algal Development and Evolution, Max Planck Institute for Biology, 72076, Tuebingen, Germany
| | - Galice Hoarau
- Faculty of Biosciences and Aquaculture, Nord University, 8026, Bodø, Norway
| | - Agnieszka P Lipinska
- CNRS, Algal Genetics Group, UMR 8227, Integrative Biology of Marine Models, Sorbonne Université, Station Biologique de Roscoff, 29680, Roscoff, France
- Department of Algal Development and Evolution, Max Planck Institute for Biology, 72076, Tuebingen, Germany
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3
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Almeida SC, Neiva J, Sousa F, Martins N, Cox CJ, Melo-Ferreira J, Guiry MD, Serrão EA, Pearson GA. A low-latitude species pump: Peripheral isolation, parapatric speciation and mating-system evolution converge in a marine radiation. Mol Ecol 2022; 31:4797-4817. [PMID: 35869812 DOI: 10.1111/mec.16623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 07/06/2022] [Accepted: 07/14/2022] [Indexed: 11/27/2022]
Abstract
Geologically recent radiations can shed light on speciation processes, but incomplete lineage sorting and introgressive gene flow render accurate evolutionary reconstruction and interpretation challenging. Independently evolving metapopulations of low dispersal taxa may provide an additional level of phylogeographic information, given sufficiently broad sampling and genome-wide sequencing. Evolution in the marine brown algal genus Fucus in the south-eastern North Atlantic was shaped by Quaternary climate-driven range shifts. Over this timescale, divergence and speciation occurred against a background of expansion-contraction cycles from multiple refugia, together with mating-system shifts from outcrossing (dioecy) to selfing hermaphroditism. We tested the hypothesis that peripheral isolation of range edge (dioecious) F. vesiculosus led to parapatric speciation and radiation of hermaphrodite lineages. Species tree methods using 876 single-copy nuclear genes and extensive geographic coverage produced conflicting topologies with respect to geographic clades of F. vesiculosus. All methods, however, revealed a new and early diverging hermaphrodite species, Fucus macroguiryi sp. nov. Both the multispecies coalescent and polymorphism-aware models (in contrast to concatenation) support sequential paraphyly in F. vesiculosus resulting from distinct evolutionary processes. Our results support (1) peripheral isolation of the southern F. vesiculosus clade prior to parapatric speciation and radiation of hermaphrodite lineages-a "low-latitude species pump". (2) Directional introgressive gene flow into F. vesiculosus around the present-day secondary contact zone (sympatric-allopatric boundary) between dioecious/hermaphrodite lineages as hermaphrodites expanded northwards, supported by concordance analysis and statistical tests of introgression. (3) Species boundaries in the extensive sympatric range are probably maintained by reproductive system (selfing in hermaphrodites) and reinforcement.
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Affiliation(s)
- Susana C Almeida
- Centre of Marine Sciences, Universidade do Algarve, Faro, Portugal
| | - João Neiva
- Centre of Marine Sciences, Universidade do Algarve, Faro, Portugal
| | - Filipe Sousa
- Centre of Marine Sciences, Universidade do Algarve, Faro, Portugal
- cE3c - Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Neusa Martins
- Centre of Marine Sciences, Universidade do Algarve, Faro, Portugal
| | - Cymon J Cox
- Centre of Marine Sciences, Universidade do Algarve, Faro, Portugal
| | - José Melo-Ferreira
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto, Campus de Vairão, R. Padre Armando Quintas, Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre s/n, Porto, Portugal
- BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, Vairão, Portugal
| | - Michael D Guiry
- AlgaeBase, Ryan Institute, National University of Ireland, Galway, Ireland
| | - Ester A Serrão
- Centre of Marine Sciences, Universidade do Algarve, Faro, Portugal
| | - Gareth A Pearson
- Centre of Marine Sciences, Universidade do Algarve, Faro, Portugal
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Bringloe TT, Zaparenkov D, Starko S, Grant WS, Vieira C, Kawai H, Hanyuda T, Filbee-Dexter K, Klimova A, Klochkova TA, Krause-Jensen D, Olesen B, Verbruggen H. Whole-genome sequencing reveals forgotten lineages and recurrent hybridizations within the kelp genus Alaria (Phaeophyceae). JOURNAL OF PHYCOLOGY 2021; 57:1721-1738. [PMID: 34510441 DOI: 10.1111/jpy.13212] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/20/2021] [Accepted: 09/05/2021] [Indexed: 05/22/2023]
Abstract
The genomic era continues to revolutionize our understanding of the evolution of biodiversity. In phycology, emphasis remains on assembling nuclear and organellar genomes, leaving the full potential of genomic datasets to answer long-standing questions about the evolution of biodiversity largely unexplored. Here, we used whole-genome sequencing (WGS) datasets to survey species diversity in the kelp genus Alaria, compare phylogenetic signals across organellar and nuclear genomes, and specifically test whether phylogenies behave like trees or networks. Genomes were sequenced from across the global distribution of Alaria (including Alaria crassifolia, A. praelonga, A. crispa, A. marginata, and A. esculenta), representing over 550 GB of data and over 2.2 billion paired reads. Genomic datasets retrieved 3,814 and 4,536 single-nucleotide polymorphisms (SNPs) for mitochondrial and chloroplast genomes, respectively, and upwards of 148,542 high-quality nuclear SNPs. WGS revealed an Arctic lineage of Alaria, which we hypothesize represents the synonymized taxon A. grandifolia. The SNP datasets also revealed inconsistent topologies across genomic compartments, and hybridization (i.e., phylogenetic networks) between Pacific A. praelonga, A. crispa, and putative A. grandifolia, and between some lineages of the A. marginata complex. Our analysis demonstrates the potential for WGS data to advance our understanding of evolution and biodiversity beyond amplicon sequencing, and that hybridization is potentially an important mechanism contributing to novel lineages within Alaria. We also emphasize the importance of surveying phylogenetic signals across organellar and nuclear genomes, such that models of mixed ancestry become integrated into our evolutionary and taxonomic understanding.
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Affiliation(s)
- Trevor T Bringloe
- School of BioSciences, University of Melbourne, Parkville Campus, Parkville, Victoria, 3010, Australia
| | - Dani Zaparenkov
- School of BioSciences, University of Melbourne, Parkville Campus, Parkville, Victoria, 3010, Australia
| | - Samuel Starko
- Department of Biology, University of Victoria, Victoria, British Columbia, V8W 2Y2, Canada
| | - William Stewart Grant
- School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, USA
| | - Christophe Vieira
- Kobe University Research Center for Inland Seas, Kobe University, Rokkodai, Nada, Kobe, Japan
| | - Hiroshi Kawai
- Kobe University Research Center for Inland Seas, Kobe University, Rokkodai, Nada, Kobe, Japan
| | - Takeaki Hanyuda
- Kobe University Research Center for Inland Seas, Kobe University, Rokkodai, Nada, Kobe, Japan
| | - Karen Filbee-Dexter
- ArcticNet, Québec Océan, Départment de biologie, Université Laval, Québec, Canada
- Institute of Marine Research, His, Norway
| | - Anna Klimova
- Kamchatka State Technical University, Petropavlovsk-Kamchatsky, 683003, Russia
| | - Tatyana A Klochkova
- Kamchatka State Technical University, Petropavlovsk-Kamchatsky, 683003, Russia
| | - Dorte Krause-Jensen
- Department of Bioscience, Aarhus University, Vejlsøvej 25, Silkeborg, DK-8600, Denmark
- Arctic Research Center, Aarhus University, Ole Worms Allé 1, Arhus C, DK-8000, Denmark
| | - Birgit Olesen
- Department of Biology, Aarhus University, Ole Worms Allé 1, Aarhus C, 8000, Denmark
| | - Heroen Verbruggen
- School of BioSciences, University of Melbourne, Parkville Campus, Parkville, Victoria, 3010, Australia
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5
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McCoy SJ, Krueger‐Hadfield SA, Mieszkowska N. Evolutionary Phycology: Toward a Macroalgal Species Conceptual Framework. JOURNAL OF PHYCOLOGY 2020; 56:1404-1413. [PMID: 32726874 PMCID: PMC7883729 DOI: 10.1111/jpy.13059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Species concepts formalize evolutionary and ecological processes, but often conflict with one another when considering the mechanisms that ultimately lead to species delimitation. Evolutionary biologists are, however, recognizing that the conceptualization of a species is separate and distinct from the delimitation of species. Indeed, if species are generally defined as separately evolving metapopulation lineages, then characteristics, such as reproductive isolation or monophyly, can be used as evidence of lineage separation and no longer conflict with the conceptualization of a species. However, little of this discussion has addressed the formalization of this evolutionary conceptual framework for macroalgal species. This may be due to the complexity and variation found in macroalgal life cycles. While macroalgal mating system variation and patterns of hybridization and introgression have been identified, complex algal life cycles generate unique eco-evolutionary consequences. Moreover, the discovery of frequent macroalgal cryptic speciation has not been accompanied by the study of the evolutionary ecology of those lineages, and, thus, an understanding of the mechanisms underlying such rampant speciation remain elusive. In this perspective, we aim to further the discussion and interest in species concepts and speciation processes in macroalgae. We propose a conceptual framework to enable phycological researchers and students alike to portray these processes in a manner consistent with dialogue at the forefront of evolutionary biology. We define a macroalgal species as an independently evolving metapopulation lineage, whereby we can test for reproductive isolation or the occupation of distinct adaptive zones, among other mechanisms, as secondary lines of supporting evidence.
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Affiliation(s)
- Sophie J. McCoy
- Department of Biological ScienceFlorida State University319 Stadium Dr.TallahasseeFlorida32312USA
| | - Stacy A. Krueger‐Hadfield
- Department of BiologyUniversity of Alabama at Birmingham1300 University BlvdBirminghamAlabama35294USA
| | - Nova Mieszkowska
- Department of Environmental SciencesUniversity of LiverpoolLiverpoolL69 3GPUK
- Marine Biological Association of the United KingdomThe LaboratoryCitadel HillPlymouthDevonPL1 2PBUK
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6
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Murúa P, Edrada-Ebel R, Muñoz L, Soldatou S, Legrave N, Müller DG, Patiño DJ, van West P, Küpper FC, Westermeier R, Ebel R, Peters AF. Morphological, genotypic and metabolomic signatures confirm interfamilial hybridization between the ubiquitous kelps Macrocystis (Arthrothamnaceae) and Lessonia (Lessoniaceae). Sci Rep 2020; 10:8279. [PMID: 32427928 PMCID: PMC7237481 DOI: 10.1038/s41598-020-65137-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 04/28/2020] [Indexed: 01/20/2023] Open
Abstract
Macrocystis pyrifera and Lessonia spicata are economically and ecologically relevant brown seaweeds that recently have been classified as members of two separated families within Laminariales (kelps). Here we describe for the first time the Macrocystis pyrifera x Lessonia spicata hybridization in the wild (Chiloe Island, Southeastern Pacific), where populations of the two parents exist sympatrically. Externally, this hybrid exhibited typical features of its parents M. pyrifera (cylindrical and flexible distal stipes, serrate frond margins and presence of sporophylls) and L. spicata (rigid and flat main stipe and first bifurcation), as well as intermediate features between them (thick unfused haptera in the holdfast). Histological sections revealed the prevalence of mucilage ducts within stipes and fronds (absent in Lessonia) and fully developed unilocular sporangia in the sporophylls. Molecular analyses confirmed the presence of the two parental genotypes for ITS1 nrDNA and the M. pyrifera genotype for two predominantly maternally inherited cytoplasmic markers (COI and rbcLS spacer) in the tissue of the hybrid. A metabolome-wide approach revealed that this hybrid is more chemically reminiscent to M. pyrifera. Nevertheless, several hits were identified as Lessonia exclusive or more remarkably, not present in any of the parent. Meiospores developed into apparently fertile gametophytes, which gave rise to F1 sporophytes that reached several millimeters before suddenly dying. In-vitro reciprocal crossing of Mar Brava gametophytes from both species revealed that although it is rare, interfamilial hybridization between the two species is possible but mostly overcome by pseudogamy of female gametophytes.
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Affiliation(s)
- Pedro Murúa
- Instituto de Acuicultura, Universidad Austral de Chile, Sede Puerto Montt, PO box 1327, Puerto Montt, Chile.
- The Scottish Association for Marine Science, Scottish Marine Institute, Culture Collection for Algae and Protozoa, Oban, Argyll, PA37 1QA, Scotland, United Kingdom.
- Aberdeen Oomycete Group, College of Life Sciences and Medicine, University of Aberdeen, Foresterhill, AB25 2ZD, Aberdeen, United Kingdom.
| | - RuAngelie Edrada-Ebel
- The Natural Products Metabolomics Group, Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, The John Arbuthnott Building, 161 Cathedral Street, Glasgow, G4 0RE, United Kingdom
| | - Liliana Muñoz
- Aberdeen Oomycete Group, College of Life Sciences and Medicine, University of Aberdeen, Foresterhill, AB25 2ZD, Aberdeen, United Kingdom
| | - Sylvia Soldatou
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Meston Building, Meston Walk, Old Aberdeen, AB24 3UE, United Kingdom
| | - Nathalie Legrave
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Meston Building, Meston Walk, Old Aberdeen, AB24 3UE, United Kingdom
| | - Dieter G Müller
- Fachbereich Biologie der Universität Konstanz, D-78457, Konstanz, Germany
| | - David J Patiño
- Instituto de Acuicultura, Universidad Austral de Chile, Sede Puerto Montt, PO box 1327, Puerto Montt, Chile
| | - Pieter van West
- Aberdeen Oomycete Group, College of Life Sciences and Medicine, University of Aberdeen, Foresterhill, AB25 2ZD, Aberdeen, United Kingdom
| | - Frithjof C Küpper
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Meston Building, Meston Walk, Old Aberdeen, AB24 3UE, United Kingdom
- School of Biological Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UU, Scotland, UK
| | - Renato Westermeier
- Instituto de Acuicultura, Universidad Austral de Chile, Sede Puerto Montt, PO box 1327, Puerto Montt, Chile
| | - Rainer Ebel
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Meston Building, Meston Walk, Old Aberdeen, AB24 3UE, United Kingdom
| | - Akira F Peters
- School of Biological Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UU, Scotland, UK
- Bezhin Rosko, 40 rue des pêcheurs, 29250, Santec, Brittany, France
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Hamel JA, Eskeland EE, Lehmann TK, Stover PL. Reproductive Costs for Hybridizing Female Anasa tristis (Hemiptera: Coreidae), but No Evidence of Selection Against Interspecific Mating. JOURNAL OF INSECT SCIENCE (ONLINE) 2018; 18:5080266. [PMID: 30165456 PMCID: PMC6110343 DOI: 10.1093/jisesa/iey080] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Indexed: 06/08/2023]
Abstract
Individuals of different species sometimes mate in nature, and such behavior often carries costs, such as wasted gametes and inviable offspring. One context in which interspecific mating commonly occurs is when closely related species come into secondary contact. Here, we tested whether reproductive isolation is greater in an area of recent secondary contact than in allopatry for two closely related insect species, and we examined whether mating between individuals of these two species constitutes reproductive interference. In Florida, two species of squash bugs (Hemiptera: Coreidae: Anasa tristis DeGeer and Anasa andresii Guérin-Méneville) have been secondarily sympatric for ≥80 generations, and male A. andresii copulate with female A. tristis. Because hybridization is often costly for females, we predicted that secondarily sympatric females would be less likely to mate with heterospecifics than would allopatric females. We found no evidence of recent selection on reproductive isolation: females from both populations were equally likely to mate with heterospecifics, and heterospecific males did not make more mating attempts than conspecifics to achieve copulations. However, female A. tristis paired with heterospecifics produced many fewer eggs and offspring than females paired with conspecifics, and this did not differ according to whether females were from allopatric or sympatric populations. Our findings show that reproductive barriers between these species existed before secondary contact. We suggest that habitat use may limit encounter frequency, and that female choice, multiple mating, and postcopulatory processes may reduce costs for females. Consequently, we suggest that mating systems and ecological factors mediate the effects of reproductive interference.
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Affiliation(s)
- Jennifer A Hamel
- Department of Biology, Elon University, McMichael Science Center, Elon, NC
- Department of Environmental Studies, Elon University, McMichael Science Center, Elon, NC
| | - Emma E Eskeland
- Department of Biology, Elon University, McMichael Science Center, Elon, NC
| | - Tyler K Lehmann
- Department of Environmental Studies, Elon University, McMichael Science Center, Elon, NC
| | - Paige L Stover
- Department of Biology, Elon University, McMichael Science Center, Elon, NC
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Montecinos AE, Guillemin ML, Couceiro L, Peters AF, Stoeckel S, Valero M. Hybridization between two cryptic filamentous brown seaweeds along the shore: analysing pre- and postzygotic barriers in populations of individuals with varying ploidy levels. Mol Ecol 2017; 26:3497-3512. [PMID: 28295812 DOI: 10.1111/mec.14098] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 02/07/2017] [Accepted: 02/07/2017] [Indexed: 01/17/2023]
Abstract
We aimed to study the importance of hybridization between two cryptic species of the genus Ectocarpus, a group of filamentous algae with haploid-diploid life cycles that include the principal genetic model organism for the brown algae. In haploid-diploid species, the genetic structure of the two phases of the life cycle can be analysed separately in natural populations. Such life cycles provide a unique opportunity to estimate the frequency of hybrid genotypes in diploid sporophytes and meiotic recombinant genotypes in haploid gametophytes allowing the effects of reproductive barriers preventing fertilization or preventing meiosis to be untangle. The level of hybridization between E. siliculosus and E. crouaniorum was quantified along the European coast. Clonal cultures (568 diploid, 336 haploid) isolated from field samples were genotyped using cytoplasmic and nuclear markers to estimate the frequency of hybrid genotypes in diploids and recombinant haploids. We identified admixed individuals using microsatellite loci, classical assignment methods and a newly developed Bayesian method (XPloidAssignment), which allows the analysis of populations that exhibit variations in ploidy level. Over all populations, the level of hybridization was estimated at 8.7%. Hybrids were exclusively observed in sympatric populations. More than 98% of hybrids were diploids (40% of which showed signs of aneuploidy) with a high frequency of rare alleles. The near absence of haploid recombinant hybrids demonstrates that the reproductive barriers are mostly postzygotic and suggests that abnormal chromosome segregation during meiosis following hybridization of species with different genome sizes could be a major cause of interspecific incompatibility in this system.
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Affiliation(s)
- Alejandro E Montecinos
- UMI, EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Universités, UPMC, PUC, UACH, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688, Roscoff cedex, France
- Facultad de Ciencias, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Marie-Laure Guillemin
- UMI, EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Universités, UPMC, PUC, UACH, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688, Roscoff cedex, France
- Facultad de Ciencias, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Lucia Couceiro
- UMI, EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Universités, UPMC, PUC, UACH, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688, Roscoff cedex, France
| | - Akira F Peters
- Bezhin Rosko, 40 rue des pêcheurs, 29250, Santec, France
| | - Solenn Stoeckel
- IGEPP, Agrocampus Ouest, INRA, Université de Rennes 1, Rennes, France
| | - Myriam Valero
- UMI, EBEA 3614, Evolutionary Biology and Ecology of Algae, CNRS, Sorbonne Universités, UPMC, PUC, UACH, Station Biologique de Roscoff, CS 90074, Place Georges Teissier, 29688, Roscoff cedex, France
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9
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Ardehed A, Johansson D, Sundqvist L, Schagerström E, Zagrodzka Z, Kovaltchouk NA, Bergström L, Kautsky L, Rafajlovic M, Pereyra RT, Johannesson K. Divergence within and among Seaweed Siblings (Fucus vesiculosus and F. radicans) in the Baltic Sea. PLoS One 2016; 11:e0161266. [PMID: 27525655 PMCID: PMC4985153 DOI: 10.1371/journal.pone.0161266] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 08/02/2016] [Indexed: 11/18/2022] Open
Abstract
Closely related taxa provide significant case studies for understanding evolution of new species but may simultaneously challenge species identification and definition. In the Baltic Sea, two dominant and perennial brown algae share a very recent ancestry. Fucus vesiculosus invaded this recently formed postglacial sea 8000 years ago and shortly thereafter Fucus radicans diverged from this lineage as an endemic species. In the Baltic Sea both species reproduce sexually but also recruit fully fertile new individuals by asexual fragmentation. Earlier studies have shown local differences in morphology and genetics between the two taxa in the northern and western Bothnian Sea, and around the island of Saaremaa in Estonia, but geographic patterns seem in conflict with a single origin of F. radicans. To investigate the relationship between northern and Estonian distributions, we analysed the genetic variation using 9 microsatellite loci in populations from eastern Bothnian Sea, Archipelago Sea and the Gulf of Finland. These populations are located in between earlier studied populations. However, instead of bridging the disparate genetic gap between N-W Bothnian Sea and Estonia, as expected from a simple isolation-by-distance model, the new populations substantially increased overall genetic diversity and showed to be strongly divergent from the two earlier analysed regions, showing signs of additional distinct populations. Contrasting earlier findings of increased asexual recruitment in low salinity in the Bothnian Sea, we found high levels of sexual reproduction in some of the Gulf of Finland populations that inhabit extremely low salinity. The new data generated in this study supports the earlier conclusion of two reproductively isolated but very closely related species. However, the new results also add considerable genetic and morphological complexity within species. This makes species separation at geographic scales more demanding and suggests a need for more comprehensive approaches to further disentangle the intriguing relationship and history of the Baltic Sea fucoids.
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Affiliation(s)
- Angelica Ardehed
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
| | - Daniel Johansson
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
| | - Lisa Sundqvist
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Ellen Schagerström
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Zuzanna Zagrodzka
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
- Department of Marine Sciences at Tjärnö, University of Gothenburg, Strömstad. Sweden
| | | | - Lena Bergström
- Department of Aquatic Resources, Swedish University of Agricultural Sciences, Öregrund, Sweden
| | - Lena Kautsky
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Marina Rafajlovic
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
- Department of Physics, University of Gothenburg, Gothenburg, Sweden
| | - Ricardo T. Pereyra
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
- Department of Marine Sciences at Tjärnö, University of Gothenburg, Strömstad. Sweden
| | - Kerstin Johannesson
- Centre for Marine Evolutionary Biology, University of Gothenburg, Gothenburg, Sweden
- Department of Marine Sciences at Tjärnö, University of Gothenburg, Strömstad. Sweden
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Monteiro CA, Paulino C, Jacinto R, Serrão EA, Pearson GA. Temporal windows of reproductive opportunity reinforce species barriers in a marine broadcast spawning assemblage. Sci Rep 2016; 6:29198. [PMID: 27373816 PMCID: PMC4931575 DOI: 10.1038/srep29198] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 06/07/2016] [Indexed: 12/02/2022] Open
Abstract
Prezygotic isolating mechanisms act to limit hybridization and maintain the genetic identity of closely-related species. While synchronous intraspecific spawning is a common phenomenon amongst marine organisms and plays an important role in reproductive success, asynchronous spawning between potentially hybridizing lineages may also be important in maintaining species boundaries. We tested this hypothesis by comparing reproductive synchrony over daily to hourly timescales in a sympatric assemblage of intertidal fucoid algae containing selfing hermaphroditic (Fucus spiralis and Fucus guiryi) and dioecious (Fucus vesiculosus and Fucus serratus) species. Our results confirm that gametes are released on semi-lunar cycles in all species. However, sister species with different mating systems showed asynchronous spawning at finer circadian timescales, thus providing evidence for a partial reproductive barrier between hermaphroditic and dioecious species. Finally, our data also emphasize the ecological, developmental, and/or physiological constraints that operate to restrict reproduction to narrow temporal windows of opportunity in the intertidal zone and more generally the role of ecological factors in marine speciation.
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Affiliation(s)
- Carla A. Monteiro
- CCMAR, Universidade do Algarve, Campus de Gambelas, 8005–139 Faro, Portugal
| | - Cristina Paulino
- CCMAR, Universidade do Algarve, Campus de Gambelas, 8005–139 Faro, Portugal
| | - Rita Jacinto
- CCMAR, Universidade do Algarve, Campus de Gambelas, 8005–139 Faro, Portugal
| | - Ester A. Serrão
- CCMAR, Universidade do Algarve, Campus de Gambelas, 8005–139 Faro, Portugal
| | - Gareth A. Pearson
- CCMAR, Universidade do Algarve, Campus de Gambelas, 8005–139 Faro, Portugal
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11
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Jueterbock A, Smolina I, Coyer JA, Hoarau G. The fate of the Arctic seaweed Fucus distichus under climate change: an ecological niche modeling approach. Ecol Evol 2016; 6:1712-24. [PMID: 27087933 PMCID: PMC4801954 DOI: 10.1002/ece3.2001] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 01/15/2016] [Accepted: 01/23/2016] [Indexed: 11/25/2022] Open
Abstract
Rising temperatures are predicted to melt all perennial ice cover in the Arctic by the end of this century, thus opening up suitable habitat for temperate and subarctic species. Canopy‐forming seaweeds provide an ideal system to predict the potential impact of climate‐change on rocky‐shore ecosystems, given their direct dependence on temperature and their key role in the ecological system. Our primary objective was to predict the climate‐change induced range‐shift of Fucus distichus, the dominant canopy‐forming macroalga in the Arctic and subarctic rocky intertidal. More specifically, we asked: which Arctic/subarctic and cold‐temperate shores of the northern hemisphere will display the greatest distributional change of F. distichus and how will this affect niche overlap with seaweeds from temperate regions? We used the program MAXENT to develop correlative ecological niche models with dominant range‐limiting factors and 169 occurrence records. Using three climate‐change scenarios, we projected habitat suitability of F. distichus – and its niche overlap with three dominant temperate macroalgae – until year 2200. Maximum sea surface temperature was identified as the most important factor in limiting the fundamental niche of F. distichus. Rising temperatures were predicted to have low impact on the species' southern distribution limits, but to shift its northern distribution limits poleward into the high Arctic. In cold‐temperate to subarctic regions, new areas of niche overlap were predicted between F. distichus and intertidal macroalgae immigrating from the south. While climate‐change threatens intertidal seaweeds in warm‐temperate regions, seaweed meadows will likely flourish in the Arctic intertidal. Although this enriches biodiversity and opens up new seaweed‐harvesting grounds, it will also trigger unpredictable changes in the structure and functioning of the Arctic intertidal ecosystem.
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Affiliation(s)
- Alexander Jueterbock
- Faculty of Biosciences and Aquaculture Nord University Universitetsalleen 11 8049 Bodø Norway
| | - Irina Smolina
- Faculty of Biosciences and Aquaculture Nord University Universitetsalleen 11 8049 Bodø Norway
| | - James A Coyer
- Shoals Marine Laboratory University of New Hampshire Durham New Hampshire 03824 USA
| | - Galice Hoarau
- Faculty of Biosciences and Aquaculture Nord University Universitetsalleen 11 8049 Bodø Norway
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12
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Robuchon M, Valero M, Gey D, Le Gall L. How does molecular-assisted identification affect our estimation of α, β and γ biodiversity? An example from understory red seaweeds (Rhodophyta) of Laminaria kelp forests in Brittany, France. Genetica 2015; 143:207-23. [PMID: 25351554 DOI: 10.1007/s10709-014-9796-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 10/15/2014] [Indexed: 12/18/2022]
Abstract
Using two distinct identification methods, one based on morphological characters only and the other combining morphological and molecular characters (integrative identification method), we investigated the differences in the biodiversity patterns of red seaweed communities associated with kelp forests at various spatial scales: the regional diversity of Brittany, France (γ-diversity), the local diversity at different Breton sites (α-diversity) and the differentiation in species diversity and abundances among those sites (β-diversity). To characterise α and β diversities, we conducted an initial survey in winter 2011 at 20 sites belonging to four different sub-regions, with specimens collected from six quadrats of 0.10 m(2) at each site, three in the tidal zone dominated by Laminaria digitata and three in the zone dominated by Laminaria hyperborea. To further characterise the regional diversity, we carried out another survey combining several sampling methods (quadrats and visual census) in different seasons (winter, spring and summer) and different years (2011 and 2012). In all, we collected 1990 specimens that were assigned to 76 taxa with the identification method based on morphological characters and 139 taxa using the integrative method. For γ and α diversity, the use of molecular characters revealed several cases of cryptic diversity and both increased the number of identified taxa and improved their taxonomic resolution. However, the addition of molecular characters for specimen identification only slightly affected estimates of β-diversity.
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Affiliation(s)
- Marine Robuchon
- Institut de Systématique, Evolution, Biodiversité, UMR 7205 CNRS, EPHE, MNHN, UPMC, Equipe Exploration, Espèces, Evolution, Muséum National d'Histoire Naturelle, Case Postale N° 39, 57 rue Cuvier, 75231, Cedex 05 Paris, France,
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13
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Hoarau G, Coyer JA, Giesbers MCWG, Jueterbock A, Olsen JL. Pre-zygotic isolation in the macroalgal genus Fucus from four contact zones spanning 100-10 000 years: a tale of reinforcement? ROYAL SOCIETY OPEN SCIENCE 2015; 2:140538. [PMID: 26064608 PMCID: PMC4448814 DOI: 10.1098/rsos.140538] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 01/13/2015] [Indexed: 06/04/2023]
Abstract
Hybrid zones provide an ideal natural experiment to study the selective forces driving evolution of reproductive barriers and speciation. If hybrid offspring are less fit than the parental species, pre-zygotic isolating barriers can evolve and strengthen in response to selection against the hybrids (reinforcement). Four contact zones between the intertidal macroalgae Fucus serratus (Fs) and Fucus distichus (Fd), characterized by varying times of sympatry and order of species introduction provide an opportunity to investigate reinforcement. We examined patterns of hybridization and reproductive isolation between Fs and Fd in: (i) northern Norway (consisting of two natural sites, 10 000 years old), (ii) the Kattegat near Denmark (Fd introduced, nineteenth century) and (iii) Iceland (Fs introduced, nineteenth century). Using 10 microsatellites and chloroplast DNA, we showed that hybridization and introgression decreased with increasing duration of sympatry. The two younger contact zones revealed 13 and 24% hybrids and several F 1 individuals, in contrast to the older contact zone with 2-3% hybrids and an absence of F 1s. Cross-fertilization experiments revealed that the reduction in hybridization in the oldest zone is consistent with increased gametic incompatibility.
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Affiliation(s)
- G. Hoarau
- Faculty of Aquaculture and Biosciences, University of Nordland, Bodø 8049, Norway
| | - J. A. Coyer
- Shoals Marine Laboratory, Cornell University, 400 Little Harbor Road, Portsmouth, NH, USA
| | - M. C. W. G. Giesbers
- Marine Benthic Ecology and Evolution Group, Centre for Ecological and Evolutionary Studies, University of Groningen, Nijenborgh 7, Groningen 9747 AG, The Netherlands
| | - A. Jueterbock
- Faculty of Aquaculture and Biosciences, University of Nordland, Bodø 8049, Norway
| | - J. L. Olsen
- Marine Benthic Ecology and Evolution Group, Centre for Ecological and Evolutionary Studies, University of Groningen, Nijenborgh 7, Groningen 9747 AG, The Netherlands
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14
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Symes LB. Community composition affects the shape of mate response functions. Evolution 2014; 68:2005-13. [PMID: 24689891 DOI: 10.1111/evo.12415] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Accepted: 03/19/2014] [Indexed: 11/28/2022]
Abstract
The evolution of mate preferences can be critical for the evolution of reproductive isolation and speciation. Heterospecific interference may carry substantial fitness costs and result in preferences where females are most responsive to the mean conspecific trait with low response to traits that differ from this value. However, when male traits are unbounded by heterospecifics, there may not be selection against females that respond to extreme trait values in the unbounded direction. To test how heterospecifics affected the shape of female response functions, I presented female Oecanthus tree crickets with synthetic calls representing a range of male calls, then measured female phonotaxis to construct response functions. The species with the fastest pulse rates in the community consistently responded to pulse rates faster than those produced by their males, whereas in the intermediate and slowest pulse rate species there was no significant difference between the male trait and the female response. This work suggests that species with the most extreme signal in the community respond to a greater range of signals, potentially resulting in a higher probability of hybridization during secondary contact, and revealing interactions between mate recognition and other aspects of sexual selection.
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Affiliation(s)
- Laurel B Symes
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, 03755.
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15
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Balakirev ES, Krupnova TN, Ayala FJ. DNA variation in the phenotypically-diverse brown alga Saccharina japonica. BMC PLANT BIOLOGY 2012; 12:108. [PMID: 22784095 PMCID: PMC3490969 DOI: 10.1186/1471-2229-12-108] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 06/21/2012] [Indexed: 05/17/2023]
Abstract
BACKGROUND Saccharina japonica (Areschoug) Lane, Mayes, Druehl et Saunders is an economically important and highly morphologically variable brown alga inhabiting the northwest Pacific marine waters. On the basis of nuclear (ITS), plastid (rbcLS) and mitochondrial (COI) DNA sequence data, we have analyzed the genetic composition of typical Saccharina japonica (TYP) and its two common morphological varieties, known as the "longipes" (LON) and "shallow-water" (SHA) forms seeking to clarify their taxonomical status and to evaluate the possibility of cryptic species within S. japonica. RESULTS The data show that the TYP and LON forms are very similar genetically in spite of drastic differences in morphology, life history traits, and ecological preferences. Both, however, are genetically quite different from the SHA form. The two Saccharina lineages are distinguished by 109 fixed single nucleotide differences as well as by seven fixed length polymorphisms (based on a 4,286 bp concatenated dataset that includes three gene regions). The GenBank database reveals a close affinity of the TYP and LON forms to S. japonica and the SHA form to S. cichorioides. The three gene markers used in the present work have different sensitivity for the algal species identification. COI gene was the most discriminant gene marker. However, we have detected instances of interspecific COI recombination reflecting putative historical hybridization events between distantly related algal lineages. The recombinant sequences show highly contrasted level of divergence in the 5'- and 3'- regions of the gene, leading to significantly different tree topologies depending on the gene segment (5'- or 3'-) used for tree reconstruction. Consequently, the 5'-COI "barcoding" region (~ 650 bp) can be misleading for identification purposes, at least in the case of algal species that might have experienced historical hybridization events. CONCLUSION Taking into account the potential roles of phenotypic plasticity in evolution, we conclude that the TYP and LON forms represent examples of algae phenotypic diversification that enables successful adaptation to contrasting shallow- and deep-water marine environments, while the SHA form is very similar to S. cichorioides and should be considered a different species. Practical applications for algal management and conservation are briefly considered.
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Affiliation(s)
- Evgeniy S Balakirev
- Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, Irvine, CA, 92697-2525, USA
- A. V. Zhirmunsky Institute of Marine Biology, Far Eastern Branch of the Russian Academy of Science, Vladivostok, 690059, Russia
| | - Tatiana N Krupnova
- Pacific Research Fisheries Centre (TINRO-Centre), Vladivostok, 690600, Russia
| | - Francisco J Ayala
- Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, Irvine, CA, 92697-2525, USA
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16
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Neiva J, Pearson GA, Valero M, Serrão EA. Fine-scale genetic breaks driven by historical range dynamics and ongoing density-barrier effects in the estuarine seaweed Fucus ceranoides L. BMC Evol Biol 2012; 12:78. [PMID: 22672720 PMCID: PMC3483196 DOI: 10.1186/1471-2148-12-78] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 05/14/2012] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Factors promoting the emergence of sharp phylogeographic breaks include restricted dispersal, habitat discontinuity, physical barriers, disruptive selection, mating incompatibility, genetic surfing and secondary contact. Disentangling the role of each in any particular system can be difficult, especially when species are evenly distributed across transition zones and dispersal barriers are not evident. The estuarine seaweed Fucus ceranoides provides a good example of highly differentiated populations along its most persistent distributional range at the present rear edge of the species distribution, in NW Iberia. Intrinsic dispersal restrictions are obvious in this species, but have not prevented F. ceranoides from vastly expanding its range northwards following the last glaciation, implying that additional factors are responsible for the lack of connectivity between neighbouring southern populations. In this study we analyze 22 consecutive populations of F. ceranoides along NW Iberia to investigate the processes generating and maintaining the observed high levels of regional genetic divergence. RESULTS Variation at seven microsatellite loci and at mtDNA spacer sequences was concordant in revealing that Iberian F. ceranoides is composed of three divergent genetic clusters displaying nearly disjunct geographical distributions. Structure and AFC analyses detected two populations with an admixed nuclear background. Haplotypic diversity was high in the W sector and very low in the N sector. Within each genetic cluster, population structure was also pervasive, although shallower. CONCLUSIONS The deep divergence between sectors coupled with the lack of support for a role of oceanographic barriers in defining the location of breaks suggested 1) that the parapatric genetic sectors result from the regional reassembly of formerly vicariant sub-populations, and 2) that the genetic discontinuities at secondary contact zones (and elsewhere) are maintained despite normal migration rates. We conclude that colonization and immigration, as sources of gene-flow, have very different genetic effects. Migration between established populations is effectively too low to prevent their differentiation by drift or to smooth historical differences inherited from the colonization process. F. ceranoides, but possibly low-dispersal species in general, appear to be unified to a large extent by historical, non-equilibrium processes of extinction and colonization, rather than by contemporary patterns of gene flow.
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Affiliation(s)
- João Neiva
- Centro de Ciências do Mar, Centro de Investigação Marinha e Ambiental - Laboratório Associado, Universidade do Algarve, Gambelas, Faro, 8005-139, Portugal
- Unité Mixte de Recherche 7144, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Station Biologique de Roscoff, Place Georges-Teissier, BP 74, Roscoff Cedex, 29682, France
| | - Gareth A Pearson
- Centro de Ciências do Mar, Centro de Investigação Marinha e Ambiental - Laboratório Associado, Universidade do Algarve, Gambelas, Faro, 8005-139, Portugal
| | - Myriam Valero
- Unité Mixte de Recherche 7144, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Station Biologique de Roscoff, Place Georges-Teissier, BP 74, Roscoff Cedex, 29682, France
| | - Ester A Serrão
- Centro de Ciências do Mar, Centro de Investigação Marinha e Ambiental - Laboratório Associado, Universidade do Algarve, Gambelas, Faro, 8005-139, Portugal
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Buchanan J, Zuccarello GC. DECOUPLING OF SHORT- AND LONG-DISTANCE DISPERSAL PATHWAYS IN THE ENDEMIC NEW ZEALAND SEAWEED CARPOPHYLLUM MASCHALOCARPUM (PHAEOPHYCEAE, FUCALES)(1). JOURNAL OF PHYCOLOGY 2012; 48:518-529. [PMID: 27011067 DOI: 10.1111/j.1529-8817.2012.01167.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The processes that produce and maintain genetic structure in organisms operate at different timescales and on different life-history stages. In marine macroalgae, gene flow occurs through gamete/zygote dispersal and rafting by adult thalli. Population genetic patterns arise from this contemporary gene flow interacting with historical processes. We analyzed spatial patterns of mitochondrial DNA variation to investigate contemporary and historical dispersal patterns in the New Zealand endemic fucalean brown alga Carpophyllum maschalocarpum (Turner) Grev. Populations bounded by habitat discontinuities were often strongly differentiated from adjoining populations over scales of tens of kilometers and intrapopulation diversity was generally low, except for one region of northeast New Zealand (the Bay of Plenty). There was evidence of strong connectivity between the northern and eastern regions of New Zealand's North Island and between the North and South Islands of New Zealand and the Chatham Islands (separated by 650 km of open ocean). Moderate haplotypic diversity was found in Chatham Islands populations, while other southern populations showed low diversity consistent with Last Glacial Maximum (LGM) retreat and subsequent recolonization. We suggest that ocean current patterns and prevailing westerly winds facilitate long-distance dispersal by floating adult thalli, decoupling genetic differentiation of Chatham Island populations from dispersal potential at the gamete/zygote stage. This study highlights the importance of encompassing the entire range of a species when inferring dispersal patterns from genetic differentiation, as realized dispersal distances can be contingent on local or regional oceanographic and historical processes.
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Affiliation(s)
- Joe Buchanan
- School of Biological Sciences, Victoria University of Wellington, P. O. Box 600, Wellington 6140, New Zealand
| | - Giuseppe C Zuccarello
- School of Biological Sciences, Victoria University of Wellington, P. O. Box 600, Wellington 6140, New Zealand
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Secondary spread of invasive species: historic patterns and underlying mechanisms of the continuing invasion of the European rockweed Fucus serratus in eastern North America. Biol Invasions 2011. [DOI: 10.1007/s10530-011-9976-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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19
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Coyer JA, Hoarau G, Costa JF, Hogerdijk B, Serrão EA, Billard E, Valero M, Pearson GA, Olsen JL. Evolution and diversification within the intertidal brown macroalgae Fucus spiralis/F. vesiculosus species complex in the North Atlantic. Mol Phylogenet Evol 2011; 58:283-96. [PMID: 21111835 DOI: 10.1016/j.ympev.2010.11.015] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 11/10/2010] [Accepted: 11/16/2010] [Indexed: 11/22/2022]
Abstract
We examined 733 individuals of Fucusspiralis from 21 locations and 1093 Fucusvesiculosus individuals from 37 locations throughout their northern hemisphere ranges using nuclear and mitochondrial markers. Three genetic entities of F. spiralis were recovered. In northern and sympatric populations, the presence of "F. spiralis Low" in the mid-intertidal and "F. spiralis High" in the high-intertidal was confirmed and both co-occurred with the sister species F. vesiculosus. The third and newly-discovered entity, "F. spiralis South", was present mainly in the southern range, where it did not co-occur with F. vesiculosus. The South entity diverged early in allopatry, then hybridized with F. vesiculosus in sympatry to produce F. spiralis Low. Ongoing parallel evolution of F. spiralis Low and F. spiralis High is most likely due to habitat preference/local selection and maintained by preferentially selfing reproductive strategies. Contemporary populations of F. spiralis throughout the North Atlantic stem from a glacial refugium around Brittany involving F. spiralis High; F. spiralis South was probably unaffected by glacial episodes. Exponential population expansion for F. vesiculosus began during the Cromer and/Holstein interglacial period (300,000-200,000 yrs BP). Following the last glacial maximum (30,000-22,000 yrs BP), a single mtDNA haplotype from a glacial refugium in SW Ireland colonized Scandinavia, the Central Atlantic islands, and the W Atlantic.
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Affiliation(s)
- J A Coyer
- Department of Marine Benthic Ecology and Evolution, Center for Ecological and Evolutionary Studies, University of Groningen, Centre for Life Sciences, AG Groningen, The Netherlands.
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Wahl M, Jormalainen V, Eriksson BK, Coyer JA, Molis M, Schubert H, Dethier M, Karez R, Kruse I, Lenz M, Pearson G, Rohde S, Wikström SA, Olsen JL. Stress ecology in fucus: abiotic, biotic and genetic interactions. ADVANCES IN MARINE BIOLOGY 2011; 59:37-105. [PMID: 21724018 DOI: 10.1016/b978-0-12-385536-7.00002-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Stress regimes defined as the synchronous or sequential action of abiotic and biotic stresses determine the performance and distribution of species. The natural patterns of stress to which species are more or less well adapted have recently started to shift and alter under the influence of global change. This was the motivation to review our knowledge on the stress ecology of a benthic key player, the macroalgal genus Fucus. We first provide a comprehensive review of the genus as an ecological model including what is currently known about the major lineages of Fucus species with respect to hybridization, ecotypic differentiation and speciation; as well as life history, population structure and geographic distribution. We then review our current understanding of both extrinsic (abiotic/biotic) and intrinsic (genetic) stress(es) on Fucus species and how they interact with each other. It is concluded that (i) interactive stress effects appear to be equally distributed over additive, antagonistic and synergistic categories at the level of single experiments, but are predominantly additive when averaged over all studies in a meta-analysis of 41 experiments; (ii) juvenile and adult responses to stress frequently differ and (iii) several species or particular populations of Fucus may be relatively unaffected by climate change as a consequence of pre-adapted ecotypes that collectively express wide physiological tolerences. Future research on Fucus should (i) include additional species, (ii) include marginal populations as models for responses to environmental stress; (iii) assess a wider range of stress combinations, including their temporal fluctuations; (iv) better differentiate between stress sensitivity of juvenile versus adult stages; (v) include a functional genomic component in order to better integrate Fucus' ecological and evolutionary responses to stress regimes and (vi) utilize a multivariate modelling approach in order to develop and understand interaction networks.
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Zaiko A, Lehtiniemi M, Narščius A, Olenin S. Assessment of bioinvasion impacts on a regional scale: a comparative approach. Biol Invasions 2010. [DOI: 10.1007/s10530-010-9928-z] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Neiva J, Pearson GA, Valero M, Serrão EA. Surfing the wave on a borrowed board: range expansion and spread of introgressed organellar genomes in the seaweed Fucus ceranoides L. Mol Ecol 2010; 19:4812-22. [PMID: 20958817 DOI: 10.1111/j.1365-294x.2010.04853.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
For many taxa, introgression represents an important source of genetic variation, but the specific contexts allowing locally introgressed material to spread and largely replace native allelic lineages throughout a species range remain poorly understood. Recent demographic-genetic simulations of spatial expansions show that the stochastic surfing of alien alleles during range expansions may constitute a general mechanism leading to extensive introgression, but empirical evidence remain scarce and difficult to distinguish from selection. In this study, we report a compelling case of such a phenomenon in the estuarine alga Fucus ceranoides. We re-assessed the phylogenetic relationships among F. ceranoides and its marine congeners F. vesiculosus and F. spiralis using nuclear, mitochondrial and chloroplast sequence data, and conducted a mtDNA phylogeographic survey in F. ceranoides. Our phylogenetic analyses revealed a recent and asymmetric introgression of a single F. vesiculosus cytoplasm into F. ceranoides. The phylogeographic scope of introgression was striking, with native and introgressed mtDNA displaying disjunct distributions south and north of the English Channel. A putative Pleistocene climatic refugium was detected in NW Iberia, and the extensive and exclusive spread of the alien cytoplasm throughout Northern Europe was inferred to have occurred concurrently with the species post-glacial, northwards range expansion. This massive spread of a foreign organelle throughout the entire post-glacial recolonization range represents good empirical evidence of an alien cytoplasm surfing the wave of a range expansion and the first description of such a phenomenon in the marine realm.
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Affiliation(s)
- João Neiva
- Centro de Ciências do Mar, Centro de Investigação Marinha e Ambiental-Laboratório Associado, Universidade do Algarve, Gambelas, 8005-139 Faro, Portugal
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Cheang CC, Chu KH, Ang PO. Phylogeography of the marine macroalga Sargassum hemiphyllum (Phaeophyceae, Heterokontophyta) in northwestern Pacific. Mol Ecol 2010; 19:2933-48. [PMID: 20584136 DOI: 10.1111/j.1365-294x.2010.04685.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Sargassum hemiphyllum is commonly found in Japan and Korea, with a variety, var. chinense, that is found distributed in the southern Chinese coast. We previously reported distinct genetic differentiation between the two taxa based on the PCR-RFLP data of plastid RubiscoL-S spacer. The present study aims at elucidating the phylogeographic pattern of S. hemiphyllum based on more markers in the nuclear and extranuclear genomes, with a view to reveal the occurrence of hybridization. The two allopatrically distributed taxa were found to be genetically distinct in nuclear ITS2, plastidial Rubisco (Rbc) and mitochondrial TrnW_I (Trn) spacers. Their divergence was postulated to be attributable to the vicariant event which resulted from the isolation of the Sea of Japan during the late Miocene (6.58-11.25 Mya). Divergence within both S. hemiphyllum and the chinense variety was observed based on Trn spacer, while the divergence in S. hemiphyllum was further confirmed in Rbc spacer. This divergence appears to correspond to the separation of the Japanese populations between the Sea of Japan and the Pacific that occurred around 0.92-2.88 Mya (the early Pleistocene). The presence of an ITS2 clone resembling var. chinense sequences in a Japanese population of S. hemiphyllum (JpNS) raises the possibility of the introgression of var. chinense individuals into S. hemiphyllum population. Compared to that between S. hemiphyllum and the chinense variety, hybridization among the Japanese and Korean populations of S. hemiphyllum is highly probable as all these individuals share a pool of nuclear ITS2 sequences, possibly attributable to incomplete concerted evolution of ITS2.
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Affiliation(s)
- Chi Chiu Cheang
- Simon F. S. Li Marine Science Laboratory, Department of Biology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
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Pearson GA, Hoarau G, Lago-Leston A, Coyer JA, Kube M, Reinhardt R, Henckel K, Serrão ETA, Corre E, Olsen JL. An expressed sequence tag analysis of the intertidal brown seaweeds Fucus serratus (L.) and F. vesiculosus (L.) (Heterokontophyta, Phaeophyceae) in response to abiotic stressors. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2010; 12:195-213. [PMID: 19609612 DOI: 10.1007/s10126-009-9208-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Accepted: 05/06/2009] [Indexed: 05/26/2023]
Abstract
In order to aid gene discovery and uncover genes responding to abiotic stressors in stress-tolerant brown algae of the genus Fucus, expressed sequence tags (ESTs) were studied in two species, Fucus serratus and Fucus vesiculosus. Clustering of over 12,000 ESTs from three libraries for heat shock/recovery and desiccation/rehydration resulted in identification of 2,503, 1,290, and 2,409 unigenes from heat-shocked F. serratus, desiccated F. serratus, and desiccated F. vesiculosus, respectively. Low overall annotation rates (18-31%) were strongly associated with the presence of long 3' untranslated regions in Fucus transcripts, as shown by analyses of predicted protein-coding sequence in annotated and nonannotated tentative consensus sequences. Posttranslational modification genes were overrepresented in the heat shock/recovery library, including many chaperones, the most abundant of which were a family of small heat shock protein transcripts, Hsp90 and Hsp70 members. Transcripts of LI818-like light-harvesting genes implicated in photoprotection were also expressed during heat shock in high light. The expression of several heat-shock-responsive genes was confirmed by quantitative reverse transcription polymerase chain reaction. However, candidate genes were notably absent from both desiccation/rehydration libraries, while the responses of the two species to desiccation were divergent, perhaps reflecting the species-specific physiological differences in stress tolerance previously established. Desiccation-tolerant F. vesiculosus overexpressed at least 17 ribosomal protein genes and two ubiquitin-ribosomal protein fusion genes, suggesting that ribosome function and/or biogenesis are important during cycles of rapid desiccation and rehydration in the intertidal zone and possibly indicate parallels with other poikilohydric organisms such as desiccation-tolerant bryophytes.
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Affiliation(s)
- Gareth A Pearson
- CCMAR, CIMAR-Laboratório Associado, FCMA, Universidade do Algarve, Gambelas, Faro, 8005-139, Portugal.
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Arnold ML, Fogarty ND. Reticulate evolution and marine organisms: the final frontier? Int J Mol Sci 2009; 10:3836-3860. [PMID: 19865522 PMCID: PMC2769149 DOI: 10.3390/ijms10093836] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Accepted: 09/02/2009] [Indexed: 11/20/2022] Open
Abstract
The role that reticulate evolution (i.e., via lateral transfer, viral recombination and/or introgressive hybridization) has played in the origin and adaptation of individual taxa and even entire clades continues to be tested for all domains of life. Though falsified for some groups, the hypothesis of divergence in the face of gene flow is becoming accepted as a major facilitator of evolutionary change for many microorganisms, plants and animals. Yet, the effect of reticulate evolutionary change in certain assemblages has been doubted, either due to an actual dearth of genetic exchange among the lineages belonging to these clades or because of a lack of appropriate data to test alternative hypotheses. Marine organisms represent such an assemblage. In the past half-century, some evolutionary biologists interested in the origin and trajectory of marine organisms, particularly animals, have posited that horizontal transfer, introgression and hybrid speciation have been rare. In this review, we provide examples of such genetic exchange that have come to light largely as a result of analyses of molecular markers. Comparisons among these markers and between these loci and morphological characters have provided numerous examples of marine microorganisms, plants and animals that possess the signature of mosaic genomes.
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Affiliation(s)
- Michael L. Arnold
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Nicole D. Fogarty
- Department of Biological Science, Florida State University, Tallahassee, Florida 32306-4295, USA; E-Mail: (N.D.F.)
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Sperm competition and offspring viability at hybridization in Australian tree frogs, Litoria peronii and L. tyleri. Heredity (Edinb) 2009; 104:141-7. [DOI: 10.1038/hdy.2009.118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Hoarau G, Coyer JA, Olsen JL. PATERNAL LEAKAGE OF MITOCHONDRIAL DNA IN A FUCUS (PHAEOPHYCEAE) HYBRID ZONE(1). JOURNAL OF PHYCOLOGY 2009; 45:621-4. [PMID: 27034038 DOI: 10.1111/j.1529-8817.2009.00679.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Eukaryotic mitochondria are mostly uniparentally (maternally) inherited, although mtDNA heteroplasmy has been reported in all major lineages. Heteroplasmy, the presence of more than one mitochondrial genome in an individual, can arise from recombination, point mutations, or by occasional transmission of the paternal mtDNA (=paternal leakage). Here, we report the first evidence of mtDNA paternal leakage in brown algae. In Denmark, where Fucus serratus L. and Fucus evanescens C. Agardh have hybridized for years, we found eight introgressed individuals that possessed the very distinct haplotypes of each parental species. The finding of heteroplasmy in individuals resulting from several generations of backcrosses suggests that paternal leakage occurred in earlier generations and has persisted through several meiotic bottlenecks.
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Affiliation(s)
- Galice Hoarau
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, University of Groningen, PO Box 14, 9750 AA Haren, the Netherlands
| | - James A Coyer
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, University of Groningen, PO Box 14, 9750 AA Haren, the Netherlands
| | - Jeanine L Olsen
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, University of Groningen, PO Box 14, 9750 AA Haren, the Netherlands
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Niwa K, Iida S, Kato A, Kawai H, Kikuchi N, Kobiyama A, Aruga Y. GENETIC DIVERSITY AND INTROGRESSION IN TWO CULTIVATED SPECIES (PORPHYRA YEZOENSIS AND PORPHYRA TENERA) AND CLOSELY RELATED WILD SPECIES OF PORPHYRA (BANGIALES, RHODOPHYTA)(1). JOURNAL OF PHYCOLOGY 2009; 45:493-502. [PMID: 27033827 DOI: 10.1111/j.1529-8817.2009.00661.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We investigated the genetic variations of the samples that were tentatively identified as two cultivated Porphyra species (Porphyra yezoensis Ueda and Porphyra tenera Kjellm.) from various natural populations in Japan using molecular analyses of plastid and nuclear DNA. From PCR-RFLP analyses using nuclear internal transcribed spacer (ITS) rDNA and plastid RUBISCO spacer regions and phylogenetic analyses using plastid rbcL and nuclear ITS-1 rDNA sequences, our samples from natural populations of P. yezoensis and P. tenera showed remarkably higher genetic variations than found in strains that are currently used for cultivation. In addition, it is inferred that our samples contain four wild Porphyra species, and that three of the four species, containing Porphyra kinositae, are closely related to cultivated Porphyra species. Furthermore, our PCR-RFLP and molecular phylogenetic analyses using both the nuclear and plastid DNA demonstrated the occurrence of plastid introgression from P. yezoensis to P. tenera and suggested the possibility of plastid introgression from cultivated P. yezoensis to wild P. yezoensis. These results imply the importance of collecting and establishing more strains of cultivated Porphyra species and related wild species from natural populations as genetic resources for further improvement of cultivated Porphyra strains.
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Affiliation(s)
- Kyosuke Niwa
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, JapanKobe University Research Center for Inland Seas, Awaji, Hyogo 656-241 and Rokkodai, Kobe, Hyogo, 657-8501, JapanCoastal Branch of Natural History Museum and Institute, Chiba, Katsuura, Chiba, 299-5242, JapanLaboratory of Aquatic Microbiology, School of Marine Sciences, Kitasato University, Sanriku, Ofunato, Iwate, 022-0101, JapanNishikamata 2-4-21, Ota-ku, Tokyo, 144-0051, Japan
| | - Satoko Iida
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, JapanKobe University Research Center for Inland Seas, Awaji, Hyogo 656-241 and Rokkodai, Kobe, Hyogo, 657-8501, JapanCoastal Branch of Natural History Museum and Institute, Chiba, Katsuura, Chiba, 299-5242, JapanLaboratory of Aquatic Microbiology, School of Marine Sciences, Kitasato University, Sanriku, Ofunato, Iwate, 022-0101, JapanNishikamata 2-4-21, Ota-ku, Tokyo, 144-0051, Japan
| | - Aki Kato
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, JapanKobe University Research Center for Inland Seas, Awaji, Hyogo 656-241 and Rokkodai, Kobe, Hyogo, 657-8501, JapanCoastal Branch of Natural History Museum and Institute, Chiba, Katsuura, Chiba, 299-5242, JapanLaboratory of Aquatic Microbiology, School of Marine Sciences, Kitasato University, Sanriku, Ofunato, Iwate, 022-0101, JapanNishikamata 2-4-21, Ota-ku, Tokyo, 144-0051, Japan
| | - Hiroshi Kawai
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, JapanKobe University Research Center for Inland Seas, Awaji, Hyogo 656-241 and Rokkodai, Kobe, Hyogo, 657-8501, JapanCoastal Branch of Natural History Museum and Institute, Chiba, Katsuura, Chiba, 299-5242, JapanLaboratory of Aquatic Microbiology, School of Marine Sciences, Kitasato University, Sanriku, Ofunato, Iwate, 022-0101, JapanNishikamata 2-4-21, Ota-ku, Tokyo, 144-0051, Japan
| | - Norio Kikuchi
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, JapanKobe University Research Center for Inland Seas, Awaji, Hyogo 656-241 and Rokkodai, Kobe, Hyogo, 657-8501, JapanCoastal Branch of Natural History Museum and Institute, Chiba, Katsuura, Chiba, 299-5242, JapanLaboratory of Aquatic Microbiology, School of Marine Sciences, Kitasato University, Sanriku, Ofunato, Iwate, 022-0101, JapanNishikamata 2-4-21, Ota-ku, Tokyo, 144-0051, Japan
| | - Atsushi Kobiyama
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, JapanKobe University Research Center for Inland Seas, Awaji, Hyogo 656-241 and Rokkodai, Kobe, Hyogo, 657-8501, JapanCoastal Branch of Natural History Museum and Institute, Chiba, Katsuura, Chiba, 299-5242, JapanLaboratory of Aquatic Microbiology, School of Marine Sciences, Kitasato University, Sanriku, Ofunato, Iwate, 022-0101, JapanNishikamata 2-4-21, Ota-ku, Tokyo, 144-0051, Japan
| | - Yusho Aruga
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, JapanKobe University Research Center for Inland Seas, Awaji, Hyogo 656-241 and Rokkodai, Kobe, Hyogo, 657-8501, JapanCoastal Branch of Natural History Museum and Institute, Chiba, Katsuura, Chiba, 299-5242, JapanLaboratory of Aquatic Microbiology, School of Marine Sciences, Kitasato University, Sanriku, Ofunato, Iwate, 022-0101, JapanNishikamata 2-4-21, Ota-ku, Tokyo, 144-0051, Japan
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Coyer JA, Hoarau G, Beszteri B, Pearson G, Olsen JL. Expressed sequence tag-derived polymorphic SSR markers for Fucus serratus and amplification in other species of Fucus. Mol Ecol Resour 2008; 9:168-70. [PMID: 21564592 DOI: 10.1111/j.1755-0998.2008.02406.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The seaweed genus Fucus is a dominant component of intertidal shores throughout the North Atlantic and North Pacific and has been the focus of considerable developmental, ecological, and evolutionary research for the past century. Here, we present details of 21 expressed sequence tag-derived simple sequence repeat markers (microsatellites). All 21 were polymorphic for F. serratus, which also display considerable cross-reactivity with the sister species F. distichus (18) and the more distantly related F. vesiculosus (13), and F. spiralis (5).
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Affiliation(s)
- J A Coyer
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, Biological Centre, University of Groningen, Kerklaan 30, PO Box 14, 9750 AA Haren, The Netherlands, Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany, CCMAR-CIMAR, F.C.M.A., University of Algarve, Gambelas, 8005-139 Faro, Portugal
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Coyer JA, Miller KA, Engle JM, Veldsink J, Cabello-Pasini A, Stam WT, Olsen JL. Eelgrass meadows in the California Channel Islands and adjacent coast reveal a mosaic of two species, evidence for introgression and variable clonality. ANNALS OF BOTANY 2008; 101:73-87. [PMID: 18006507 PMCID: PMC2701847 DOI: 10.1093/aob/mcm288] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2007] [Revised: 08/30/2007] [Accepted: 10/01/2007] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS Seagrasses are important facilitator species in shallow, soft-bottom marine environments worldwide and, in many places, are threatened by coastal development and eutrophication. One narrow-leaved species (Zostera marina) and one wide-leaved species, variously designated as Z. marina, Z. pacifica or Z. asiatica, are found off the California Channel Islands and adjacent California-Mexico coast. The aim of the present study was to confirm species identification genetically and to link patterns of genetic diversity, connectivity and hybridization among and within the populations with historical sea levels (Ice Age) or the contemporary environment. METHODS Samples (n = 11-100) were collected from 28 sites off five California Channel Islands and six sites off the adjacent coast of southern California and Baja California, Mexico. DNA polymorphisms of the rDNA-ITS (internal transcribed spacer) cistron (nuclear), the matK intron (chloroplast) and nine microsatellite loci (nuclear) were examined in a population genetic and phylogeographic context. KEY RESULTS All wide-leaved individuals were Z. pacifica, whereas narrow-leaved forms were Z. marina. Microsatellite genotypes were consistent with hybridization between the two species in three populations. The present distribution of Z. pacifica follows a glacial age land mass rather than present oceanographic regimes, but no link was observed between the present distribution of Z. marina and past or present environments. Island populations of Z. marina often were clonal and characterized by low genotypic diversity compared with populations along the Baja California coast. The high level of clonal connectivity around Santa Catalina Island indicated the importance of dispersal and subsequent re-establishment of vegetative fragments. CONCLUSIONS The pristine environmental conditions of offshore islands do not guarantee maximum genetic diversity. Future restoration and transplantation efforts of seagrasses must recognize cryptic species and consider the degree of both genetic and genotypic variation in candidate donor populations.
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Affiliation(s)
- J A Coyer
- Department of Marine Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands.
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Coyer JA, Hoarau G, Stam WT, Olsen JL. Hybridization and introgression in a mixed population of the intertidal seaweeds Fucus evanescens and F. serratus. J Evol Biol 2007; 20:2322-33. [PMID: 17956394 DOI: 10.1111/j.1420-9101.2007.01411.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The introduced Fucus evanescens (hermaphroditic) and the native F. serratus (dioecious) have been in secondary contact along the Danish coast of the Kattegat Sea for 60-100 years and dioecious hybrids have been observed at Blushøj for several years. Hybridization in Fucus is unusual because it appears to always involve a hermaphroditic and a dioecious parental pair. We determined the degree and spatial patterns of introgression for 286 individuals using 10 microsatellite loci and cpDNA. Hybrids accounted for nearly 13% of the population, yet parental species were well differentiated (F(ST) = 0.633). The presence of F. evanescens chloroplasts in 100% of F(1) hybrids revealed asymmetrical hybridization. Fucus evanescens cpDNA was observed in 50% of introgressed and 5.4% of pure F. serratus, but no F. serratus cpDNA was found in F. evanescens. In contrast, nuclear DNA introgression was symmetrical with an equal amount ( approximately 1.5%) of genes introgressed into each parental species. Survivorship and viability data suggest selection against hybrids in the hybrid zone.
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Affiliation(s)
- J A Coyer
- Department of Benthic Ecology and Evolution, Centre for Ecological and Evolutionary Studies, University of Groningen, AA Haren, The Netherlands.
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Ruane LG, Donohue K. Environmental effects on pollen-pistil compatibility between Phlox cuspidata and P. drummondii (Polemoniaceae): implications for hybridization dynamics. AMERICAN JOURNAL OF BOTANY 2007; 94:219-227. [PMID: 21642224 DOI: 10.3732/ajb.94.2.219] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Postpollination mechanisms of reproductive isolation can critically influence the amount of gene flow between hybridizing species. While much evidence exists for genetically based pollen-pistil incompatibility, we show that environmental variation also influences the postpollination performance of heterospecific pollen in the annual Phlox hybrid system. Thus, the environmental segregation of species can influence hybridization dynamics. We found that P. cuspidata was restricted to soils of low Ca concentrations in the field and performed better under experimentally low Ca; P. drummondii was able to inhabit high-Ca soils and sometimes performed better in this environment. To determine whether soil Ca influenced pollen-pistil compatibility in a manner that alters pollen siring success, single-donor pollinations were performed in a completely factorial crossing design between species, maternal Ca environments, and paternal Ca environments. Maternal and paternal environments interacted in their effects on pollen-pistil compatibility for both inter- and intraspecific crosses, such that pollen performance was highest when mothers and fathers were grown in different soil Ca environments. These results suggest that when Phlox species predictably inhabit different environments, environmental heterogeneity can impede the processes of speciation and local adaptation by enhancing the performance of pollen dispersed across species and environments.
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Affiliation(s)
- Lauren G Ruane
- Department of Organismic and Evolutionary Biology, Harvard University Herbaria, 22 Divinity Avenue, Cambridge, Massachusetts 02138 USA
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Coyer JA, Hoarau G, Pearson GA, Serrão EA, Stam WT, Olsen JL. Convergent adaptation to a marginal habitat by homoploid hybrids and polyploid ecads in the seaweed genus Fucus. Biol Lett 2006; 2:405-8. [PMID: 17148415 PMCID: PMC1686178 DOI: 10.1098/rsbl.2006.0489] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Accepted: 04/11/2006] [Indexed: 11/12/2022] Open
Abstract
Hybridization and polyploidy are two major sources of genetic variability that can lead to adaptation in new habitats. Most species of the brown algal genus Fucus are found along wave-swept rocky shores of the Northern Hemisphere, but some species have adapted to brackish and salt marsh habitats. Using five microsatellite loci and mtDNA RFLP, we characterize two populations of morphologically similar, muscoides-like Fucus inhabiting salt marshes in Iceland and Ireland. The Icelandic genotypes were consistent with Fucus vesiculosus x Fucus spiralis F1 hybrids with asymmetrical hybridization, whereas the Irish ones consisted primarily of polyploid F. vesiculosus.
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Affiliation(s)
- James A Coyer
- Department of Marine Biology, CEES, University of Groningen, 9750 AA Haren, The Netherlands.
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Chevolot M, Hoarau G, Rijnsdorp AD, Stam WT, Olsen JL. Phylogeography and population structure of thornback rays (Raja clavata L., Rajidae). Mol Ecol 2006; 15:3693-705. [PMID: 17032267 DOI: 10.1111/j.1365-294x.2006.03043.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The phylogeography of thornback rays (Raja clavata) was assessed from European waters, using five nuclear microsatellite loci and mitochondrial cytochome b sequences. Strong regional differentiation was found between the Mediterranean basin, the Azores and the European continental shelf. Allelic and haplotype diversities were high in Portuguese populations, consistent with the existence of a refugium along the Iberian Peninsula. Unexpectedly, high diversity was also found in the English Channel/North Sea area. The lowest genetic diversity was found in the Black Sea. Populations sampled from the Mediterranean, Adriatic and Black Seas were characterized by a single mitochondrial haplotype. This haplotype was also the most ancestral and widespread outside of the Mediterranean basin except for the Azores. Populations from the Azores were dominated by a second ancestral haplotype which was shared with British populations. Results from multidimensional scaling, amova and nested clade analysis indicate that British waters are a secondary contact zone recolonized from at least two refugia--one around the Iberian Peninsula and one possibly in the Azores. Links to a potential refugium known as the Hurd Deep, between Cornwall and Brittany, are discussed. Finally, a historical demographic analysis indicates that thornback ray populations started to expand between 580,000 and 362,000 years ago, which suggests that the Last Glacial Maximum (20,000 years ago) had mainly affected the distribution of populations rather than population size.
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Affiliation(s)
- Malia Chevolot
- Department of Marine Benthic Ecology and Evolution, Center for Ecological and Evolutionary Sciences, Biological Center, University of Groningen, Postbus 14, 9750 AA Haren, The Netherlands.
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Coyer JA, Hoarau G, Oudot-Le Secq MP, Stam WT, Olsen JL. A mtDNA-based phylogeny of the brown algal genus Fucus (Heterokontophyta; Phaeophyta). Mol Phylogenet Evol 2006; 39:209-22. [PMID: 16495086 DOI: 10.1016/j.ympev.2006.01.019] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2005] [Revised: 12/05/2005] [Accepted: 01/12/2006] [Indexed: 11/16/2022]
Abstract
Species of Fucus are among the dominant seaweeds along Northern Hemisphere shores, but taxonomic designations often are confounded by significant intraspecific morphological variability. We analyzed intra- and inter-specific phylogenetic relationships within the genus (275 individuals representing 16 taxa) using two regions of the mitochondrion: a variable intergenic spacer and a conserved portion of the 23S subunit. Bayesian ML and MP analyses verified a shallow phylogeny with two major lineages (previously reported) and resolved some intra-lineage relationships. Significant species-level paraphyly/polyphyly was observed within lineages 1A and 2. Despite higher species richness in the North Atlantic, a North Pacific origin of the genus is supported by a gradient of decreasing haplotype and nucleotide diversities in F. distichus from the North Pacific to the East Atlantic.
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Affiliation(s)
- James A Coyer
- Department of Marine Biology, Centre for Ecological and Evolutionary Studies, University of Groningen, 9750 AA Haren, The Netherlands.
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Engel CR, Daguin C, Serrão EA. Genetic entities and mating system in hermaphroditic Fucus spiralis and its close dioecious relative F. vesiculosus (Fucaceae, Phaeophyceae). Mol Ecol 2005; 14:2033-46. [PMID: 15910325 DOI: 10.1111/j.1365-294x.2005.02558.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To date, molecular markers have not settled the question of the specific status of the closely related, but phylogenetically unresolved, brown seaweeds, hermaphroditic Fucus spiralis and dioecious Fucus vesiculosus, nor their propensity for natural hybridization. To test the degree of species integrity and to assess effect of the mating system on the population genetic structure, 288 individuals coming from parapatric (discontinuous) and sympatric (contiguous) spatial configurations at two sites were genotyped with five microsatellite loci. Using a Bayesian admixture analysis, our results show that F. spiralis and F. vesiculosus comprise clearly distinct genetic entities (clusters) generally characterized by cosexual and unisexual individuals, respectively. Genetic diversity within each entity suggests that F. spiralis reproduces primarily through selfing while F. vesiculosus is characterized by an endogamous breeding regime. Nevertheless, aberrant sexual phenotypes were observed in each cluster, no diagnostic alleles were revealed and 10% of study individuals were intermediate between the two genetic entities. This pattern can be explained by recent divergence of two taxa with retention of ancestral polymorphism or asymmetrical, introgressive hybridization. However, given (i) coincident monomorphism at three loci in spiralis clusters and (ii) that significantly more intermediates were observed in sympatric stations than in parapatric stations, we argue that interspecific gene flow has occurred after divergence of the two taxa. Finally, we show that whether recently separated or recently introgressive, the divergent breeding systems probably contribute to species integrity in these two taxa.
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Affiliation(s)
- C R Engel
- CCMAR-Centre of Marine Sciences, FCMA, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
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Voisin M, Engel CR, Viard F. Differential shuffling of native genetic diversity across introduced regions in a brown alga: aquaculture vs. maritime traffic effects. Proc Natl Acad Sci U S A 2005; 102:5432-7. [PMID: 15802466 PMCID: PMC556235 DOI: 10.1073/pnas.0501754102] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2004] [Indexed: 11/18/2022] Open
Abstract
Worldwide marine invaders, such as the brown alga Undaria pinnatifida, offer challenging models for unraveling the apparent paradox of sustainable settlement of exotic species over a large spectrum of environments. Two intergenic noncoding mitochondrial loci were found to be highly informative at the within-species level. Twenty-five haplotypes were found over the whole dataset (333 base pairs, 524 individuals, and 24 populations). The native range showed striking population genetic structure stemming from low diversity within and high differentiation among populations, a pattern not observed in the introduced range of this seaweed. Contrary to classical expectations of founding effects associated with accidental introduction of exotic species, most of the introduced populations showed high genetic diversity. At the regional scale, genetic diversity and sequence divergence showed contrasting patterns in the two main areas of introduction (Europe and Australasia), suggesting different processes of introduction in the two regions. Gene genealogy analyses point to aquaculture as a major vector of introduction and spread in Europe but implicate maritime traffic in promoting recurrent migration events from the native range to Australasia. The multiplicity of processes and genetic signatures associated with the successful invasion confirms that multiple facets of global change, e.g., aquaculture practices, alteration of habitats, and increased traffic, act in synergy at the worldwide level, facilitating successful pandemic introductions.
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Affiliation(s)
- Marie Voisin
- Equipe Evolution et Génétique des Populations Marines, Unité Mixte de Recherche, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie 7144, Station Biologique de Roscoff, Place Georges-Teissier, BP 74, 29682 Roscoff Cedex, France
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Coyer JA, Hoarau G, Stam WT, Olsen JL. Geographically specific heteroplasmy of mitochondrial DNA in the seaweed, Fucus serratus (Heterokontophyta: Phaeophyceae, Fucales). Mol Ecol 2004; 13:1323-6. [PMID: 15078467 DOI: 10.1111/j.1365-294x.2004.02128.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The presence of more than one type of mitochondrial DNA within the same organism (mtDNA heteroplasmy) has been reported in vertebrates, invertebrates, basidiomycetes and some angiosperms, but never in marine (macro)algae. We examined sequence differences in a 135-base pair (bp) region of the nad11 gene in mitochondria of the intertidal rockweed, Fucus serratus, using single-strand conformation polymorphism (SSCP). Each of 70 and 22 individuals from Blushøj (Denmark) and Oskarshamn (Sweden), respectively, displayed haplotypes 2, 3, and 4 (= mtDNA heteroplasmy), whereas only haplotype 2 was found in each of 24 individuals from locations in Spain, France, Ireland, Iceland and Norway. As Blushøj and Oskarshamn were among the last areas to emerge from ice cover during the Last Glacial Maximum (18000-20000 years BP), the geographically specific heteroplasmy may represent a founder effect and therefore, a valuable marker for understanding the role of post-Ice Age recolonization. Geographically specific heteroplasmy also has important implications in phylogeographical studies based on mtDNA sequences.
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Affiliation(s)
- J A Coyer
- Department of Marine Biology, Centre for Ecological and Evolutionary Studies, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands.
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Coyer JA, Peters AF, Stam WT, Olsen JL. Post-ice age recolonization and differentiation of Fucus serratus L. (Phaeophyceae; Fucaceae) populations in Northern Europe. Mol Ecol 2003; 12:1817-29. [PMID: 12803634 DOI: 10.1046/j.1365-294x.2003.01850.x] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The seaweed Fucus serratus is hypothesized to have evolved in the North Atlantic and present populations are thought to reflect recolonization from a southern refugium since the last glacial maximum 18 000-20 000 years bp. We examined genetic structure across several spatial scales by analysing seven microsatellite loci in populations collected from 21 localities throughout the species' range. Spatial auto-correlation analysis of seven microsatellite loci revealed no evidence for spatial clustering of alleles on a scale of 100 m despite limited gamete dispersal in F. serratus of approximately 2 m from parental individuals. Pairwise theta analysis suggested that the minimal panmictic unit for F. serratus was between 0.5 and 2 km. Isolation by distance was significant along some contiguous coastlines. Population differentiation was strong within the Skagerrak-Kattegat-Baltic Seas (SKB) (global theta= 0.17) despite a short history of approximately 7500 years. A neighbour-joining tree based on Reynold's distances computed from the microsatellite data revealed a central assemblage of populations on the Brittany Peninsula surrounded by four well-supported clusters consisting of the SKB, the North Sea (Ireland, Helgoland), and two populations from the northern Spanish coast. Samples from Iceland and Nova Scotia were most closely aligned with northwest Sweden and Brittany, respectively. When sample sizes were standardized (N = 41), allelic diversity was twofold higher for Brittany populations than for populations to the north and threefold higher than southern populations. The Brittany region may be a refugium or a recolonized area, whereas the Spanish populations most likely reflect present-day edge populations that have undergone repeated bottlenecks as a consequence of thermally induced cycles of recolonization and extinction.
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Affiliation(s)
- J A Coyer
- Department of Marine Biology, Centre for Ecological and Evolutionary Studies, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands.
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