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Šarhanová P, Majeský Ľ, Sochor M. A novel strategy to study apomixis, automixis, and autogamy in plants. PLANT REPRODUCTION 2024:10.1007/s00497-024-00499-6. [PMID: 38431531 DOI: 10.1007/s00497-024-00499-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 02/02/2024] [Indexed: 03/05/2024]
Abstract
KEY MESSAGE The combination of a flow cytometric seed screen and genotyping of each single seed offers a cost-effective approach to detecting complex reproductive pathways in flowering plants. Reproduction may be seen as one of the driving forces of evolution. Flow cytometric seed screen and genotyping of parents and progeny are commonly employed techniques to discern various modes of reproduction in flowering plants. Nevertheless, both methods possess limitations constraining their individual capacity to investigate reproductive modes thoroughly. We implemented both methods in a novel manner to analyse reproduction pathways using a carefully selected material of parental individuals and their seed progeny. The significant advantage of this approach lies in its ability to apply both methods to a single seed. The introduced methodology provides valuable insights into discerning the levels of apomixis, sexuality, and selfing in complex Rubus taxa. The results may be explained by the occurrence of automixis in Rubus, which warrants further investigation. The approach showcased its effectiveness in a different apomictic system, specifically in Taraxacum. Our study presents a comprehensive methodological approach for determining the mode of reproduction where flow cytometry loses its potential. It provides a reliable and cost-effective method with significant potential in biosystematics, population genetics, and crop breeding.
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Affiliation(s)
- Petra Šarhanová
- Department of Botany and Zoology, Masaryk University, Kotlářská 267/2, 611 37, Brno, Czech Republic.
| | - Ľuboš Majeský
- Faculty of Science, Department of Botany, Palacký University in Olomouc, Šlechtitelů 27, 783 71, Olomouc-Holice, Czech Republic
| | - Michal Sochor
- Centre of the Region Haná for Biotechnological and Agricultural Research, Crop Research Institute, Šlechtitelů 29, 78371, Olomouc, Czech Republic
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2
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Tarkhnishvili D, Yanchukov A, Böhne A. Editorial: Advantages, limitations, and evolutionary constraints of asexual reproduction: An empirical approach. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1184306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
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3
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Forni G, Mikheyev AS, Luchetti A, Mantovani B. Gene transcriptional profiles in gonads of Bacillus taxa (Phasmida) with different cytological mechanisms of automictic parthenogenesis. ZOOLOGICAL LETTERS 2022; 8:14. [PMID: 36435814 PMCID: PMC9701443 DOI: 10.1186/s40851-022-00197-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
The evolution of automixis - i.e., meiotic parthenogenesis - requires several features, including ploidy restoration after meiosis and maintenance of fertility. Characterizing the relative contribution of novel versus pre-existing genes and the similarities in their expression and sequence evolution is fundamental to understand the evolution of reproductive novelties. Here we identify gonads-biased genes in two Bacillus automictic stick-insects and compare their expression profile and sequence evolution with a bisexual congeneric species. The two parthenogens restore ploidy through different cytological mechanisms: in Bacillus atticus, nuclei derived from the first meiotic division fuse to restore a diploid egg nucleus, while in Bacillus rossius, diploidization occurs in some cells of the haploid blastula through anaphase restitution. Parthenogens' gonads transcriptional program is found to be largely assembled from genes that were already present before the establishment of automixis. The three species transcriptional profiles largely reflect their phyletic relationships, yet we identify a shared core of genes with gonad-biased patterns of expression in parthenogens which are either male gonads-biased in the sexual species or are not differentially expressed there. At the sequence level, just a handful of gonads-biased genes were inferred to have undergone instances of positive selection exclusively in the parthenogen species. This work is the first to explore the molecular underpinnings of automixis in a comparative framework: it delineates how reproductive novelties can be sustained by genes whose origin precedes the establishment of the novelty itself and shows that different meiotic mechanisms of reproduction can be associated with a shared molecular ground plan.
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Affiliation(s)
- Giobbe Forni
- Dip. Scienze Biologiche, Geologiche e Ambientali (BiGeA), University of Bologna, 40126, Bologna, Italy
- Dip. Scienze Agrarie e Ambientali, University of Milano, Milano, Italy
| | - Alexander S Mikheyev
- Australian National University, ACT, Canberra, 2600, Australia
- Okinawa Institute of Science and Technology, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan
| | - Andrea Luchetti
- Dip. Scienze Biologiche, Geologiche e Ambientali (BiGeA), University of Bologna, 40126, Bologna, Italy.
| | - Barbara Mantovani
- Dip. Scienze Biologiche, Geologiche e Ambientali (BiGeA), University of Bologna, 40126, Bologna, Italy
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4
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Archetti M. Evidence from automixis with inverted meiosis for the maintenance of sex by loss of complementation. J Evol Biol 2021; 35:40-50. [PMID: 34927297 DOI: 10.1111/jeb.13975] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 11/30/2022]
Abstract
The adaptive value of sexual reproduction is still debated. A short-term disadvantage of asexual reproduction is loss of heterozygosity, which leads to the unmasking of recessive deleterious mutations. The cost of this loss of complementation is predicted to be higher than the twofold cost of meiosis for most types of asexual reproduction. Automixis with terminal fusion of sister nuclei is especially vulnerable to the effect of loss of complementation. It is found, however, in some taxa including oribatid mites, the most prominent group of ancient asexuals. Here, I show that automixis with terminal fusion is stable if it is associated with inverted meiosis and that this appears to be the case in nature, notably in oribatid mites. The existence of automixis with terminal fusion, and its co-occurrence with inverted meiosis, therefore, is consistent with the hypothesis that loss of complementation is important in the evolution of sexual reproduction.
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Affiliation(s)
- Marco Archetti
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA
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Kuhn A, Aron S, Hardy OJ. Detection of Cryptic Sex in Automictic Populations: Theoretical Expectations and a Case Study in Cataglyphis Desert Ants. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.741959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Reproductive strategies are diverse and a whole continuum of mixed systems lies between strict sexuality and strict clonality (apomixis), including automixis, a parthenogenetic mode of reproduction involving a meiosis and increasing homozygosity over generations. These various systems impact the genetic structure of populations, which can therefore be used to infer reproductive strategies in natural populations. Here, we first develop a mathematical model, validated by simulations, to predict heterozygosity and inbreeding in mixed sexual-automictic populations. It highlights the predominant role of the rate of heterozygosity loss experienced during automixis (γ), which is locus dependent. When γ is low, mixed populations behave like purely sexual ones until sex becomes rare. In contrast, when γ is high, the erosion of genetic diversity is tightly correlated to the rate of sex, so that the individual inbreeding coefficient can inform on the ratio of sexual/asexual reproduction. In the second part of this study, we used our model to test the presence of cryptic sex in a hybridogenetic Cataglyphis ant where new queens are produced parthenogenetically, leaving males with an apparent null fitness while they are essential to colony development as sperm is required to produce workers. Occasional sexual production of queens could resolve this paradox by providing males some fertile progeny. To determine whether this occurs in natural populations, we simulated genotypic datasets in a population under various regimes of sexual vs. asexual reproduction for queen production and compared the distribution of inbreeding, expected heterozygosity and inter-individual relatedness coefficients with those observed in a natural population of Cataglyphis mauritanica using microsatellites. Our simulations show that the distribution of inter-individual relatedness coefficients was particularly informative to assess the relative rate of sexual/asexual reproduction, and our dataset was compatible with pure parthenogenesis but also with up to 2% sexual reproduction. Our approach, implemented in an R script, should be useful to assess reproductive strategies in other biological models.
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6
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Papaioannou IA, Dutreux F, Peltier FA, Maekawa H, Delhomme N, Bardhan A, Friedrich A, Schacherer J, Knop M. Sex without crossing over in the yeast Saccharomycodes ludwigii. Genome Biol 2021; 22:303. [PMID: 34732243 PMCID: PMC8567612 DOI: 10.1186/s13059-021-02521-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 10/20/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Intermixing of genomes through meiotic reassortment and recombination of homologous chromosomes is a unifying theme of sexual reproduction in eukaryotic organisms and is considered crucial for their adaptive evolution. Previous studies of the budding yeast species Saccharomycodes ludwigii suggested that meiotic crossing over might be absent from its sexual life cycle, which is predominated by fertilization within the meiotic tetrad. RESULTS We demonstrate that recombination is extremely suppressed during meiosis in Sd. ludwigii. DNA double-strand break formation by the conserved transesterase Spo11, processing and repair involving interhomolog interactions are required for normal meiosis but do not lead to crossing over. Although the species has retained an intact meiotic gene repertoire, genetic and population analyses suggest the exceptionally rare occurrence of meiotic crossovers in its genome. A strong AT bias of spontaneous mutations and the absence of recombination are likely responsible for its unusually low genomic GC level. CONCLUSIONS Sd. ludwigii has followed a unique evolutionary trajectory that possibly derives fitness benefits from the combination of frequent mating between products of the same meiotic event with the extreme suppression of meiotic recombination. This life style ensures preservation of heterozygosity throughout its genome and may enable the species to adapt to its environment and survive with only minimal levels of rare meiotic recombination. We propose Sd. ludwigii as an excellent natural forum for the study of genome evolution and recombination rates.
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Affiliation(s)
| | - Fabien Dutreux
- Université de Strasbourg, CNRS, GMGM UMR 7156, Strasbourg, France
| | - France A. Peltier
- Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
| | - Hiromi Maekawa
- Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
- Current affiliation: Faculty of Agriculture, Kyushu University, Fukuoka, Japan
| | - Nicolas Delhomme
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Amit Bardhan
- Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
| | - Anne Friedrich
- Université de Strasbourg, CNRS, GMGM UMR 7156, Strasbourg, France
| | - Joseph Schacherer
- Université de Strasbourg, CNRS, GMGM UMR 7156, Strasbourg, France
- Institut Universitaire de France (IUF), Paris, France
| | - Michael Knop
- Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
- German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany
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7
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Hojsgaard D, Schartl M. Skipping sex: A nonrecombinant genomic assemblage of complementary reproductive modules. Bioessays 2020; 43:e2000111. [PMID: 33169369 DOI: 10.1002/bies.202000111] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 09/26/2020] [Accepted: 09/29/2020] [Indexed: 02/03/2023]
Abstract
The unusual occurrence and developmental diversity of asexual eukaryotes remain a puzzle. De novo formation of a functioning asexual genome requires a unique assembly of sets of genes or gene states to disrupt cellular mechanisms of meiosis and gametogenesis, and to affect discrete components of sexuality and produce clonal or hemiclonal offspring. We highlight two usually overlooked but essential conditions to understand the molecular nature of clonal organisms, that is, a nonrecombinant genomic assemblage retaining modifiers of the sexual program, and a complementation between altered reproductive components. These subtle conditions are the basis for physiologically viable and genetically balanced transitions between generations. Genomic and developmental evidence from asexual animals and plants indicates the lack of complementation of molecular changes in the sexual reproductive program is likely the main cause of asexuals' rarity, and can provide an explanatory frame for the developmental diversity and lability of developmental patterns in some asexuals as well as for the discordant time to extinction estimations.
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Affiliation(s)
- Diego Hojsgaard
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Albrecht-von-Haller Institute for Plant Sciences, University of Goettingen, Goettingen, Germany
| | - Manfred Schartl
- Department of Developmental Biochemistry, Biocenter, University of Wuerzburg, Wuerzburg, Germany.,The Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, USA
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Carpentier F, Rodríguez de la Vega RC, Branco S, Snirc A, Coelho MA, Hood ME, Giraud T. Convergent recombination cessation between mating-type genes and centromeres in selfing anther-smut fungi. Genome Res 2019; 29:944-953. [PMID: 31043437 PMCID: PMC6581054 DOI: 10.1101/gr.242578.118] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 04/29/2019] [Indexed: 12/28/2022]
Abstract
The degree of selfing has major impacts on adaptability and is often controlled by molecular mechanisms determining mating compatibility. Changes in compatibility systems are therefore important evolutionary events, but their underlying genomic mechanisms are often poorly understood. Fungi display frequent shifts in compatibility systems, and their small genomes facilitate elucidation of the mechanisms involved. In particular, linkage between the pre- and postmating compatibility loci has evolved repeatedly, increasing the odds of gamete compatibility under selfing. Here, we studied the mating-type chromosomes of two anther-smut fungi with unlinked mating-type loci despite a self-fertilization mating system. Segregation analyses and comparisons of high-quality genome assemblies revealed that these two species displayed linkage between mating-type loci and their respective centromeres. This arrangement renders the same improved odds of gamete compatibility as direct linkage of the two mating-type loci under the automictic mating (intratetrad selfing) of anther-smut fungi. Recombination cessation was found associated with a large inversion in only one of the four linkage events. The lack of trans-specific polymorphism at genes located in nonrecombining regions and linkage date estimates indicated that the events of recombination cessation occurred independently in the two sister species. Our study shows that natural selection can repeatedly lead to similar genomic patterns and phenotypes, and that different evolutionary paths can lead to distinct yet equally beneficial responses to selection. Our study further highlights that automixis and gene linkage to centromeres have important genetic and evolutionary consequences, while being poorly recognized despite being present in a broad range of taxa.
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Affiliation(s)
- Fantin Carpentier
- Ecologie Systématique Evolution, Bâtiment 360, Univ. Paris-Sud, AgroParisTech, CNRS, Université Paris-Saclay, 91400 Orsay, France
| | - Ricardo C Rodríguez de la Vega
- Ecologie Systématique Evolution, Bâtiment 360, Univ. Paris-Sud, AgroParisTech, CNRS, Université Paris-Saclay, 91400 Orsay, France
| | - Sara Branco
- Ecologie Systématique Evolution, Bâtiment 360, Univ. Paris-Sud, AgroParisTech, CNRS, Université Paris-Saclay, 91400 Orsay, France
| | - Alodie Snirc
- Ecologie Systématique Evolution, Bâtiment 360, Univ. Paris-Sud, AgroParisTech, CNRS, Université Paris-Saclay, 91400 Orsay, France
| | - Marco A Coelho
- UCIBIO-REQUIMTE, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Michael E Hood
- Department of Biology, Amherst College, Amherst, Massachusetts 01002, USA
| | - Tatiana Giraud
- Ecologie Systématique Evolution, Bâtiment 360, Univ. Paris-Sud, AgroParisTech, CNRS, Université Paris-Saclay, 91400 Orsay, France
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9
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Affiliation(s)
| | - David Porter
- Department of Botany, University of Georgia, Athens, Georgia 30602
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10
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Haag CR, Theodosiou L, Zahab R, Lenormand T. Low recombination rates in sexual species and sex-asex transitions. Philos Trans R Soc Lond B Biol Sci 2017; 372:20160461. [PMID: 29109224 PMCID: PMC5698623 DOI: 10.1098/rstb.2016.0461] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/2017] [Indexed: 12/11/2022] Open
Abstract
In most sexual, diploid eukaryotes, at least one crossover occurs between each pair of homologous chromosomes during meiosis, presumably in order to ensure proper segregation. Well-known exceptions to this rule are species in which one sex does not recombine and specific chromosomes lacking crossover. We review other possible exceptions, including species with chromosome maps of less than 50 cM in one or both sexes. We discuss the idea that low recombination rates may favour sex-asex transitions, or, alternatively may be a consequence of it. We then show that a yet undescribed species of brine shrimp Artemia from Kazakhstan (A sp. Kazakhstan), the closest known relative of the asexual Artemia parthenogenetica, has one of the shortest genetic linkage maps known. Based on a family of 42 individuals and 589 RAD markers, we find that many linkage groups are considerably shorter than 50 cM, suggesting either no obligate crossover or crossovers concentrated at terminal positions with little effect on recombination. We contrast these findings with the published map of the more distantly related sexual congener, A. franciscana, and conclude that the study of recombination in non-model systems is important to understand the evolutionary causes and consequences of recombination.This article is part of the themed issue 'Evolutionary causes and consequences of recombination rate variation in sexual organisms'.
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Affiliation(s)
- Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS), Université de Montpellier-Université Paul-Valéry Montpellier-École Pratique des Hautes Études, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Loukas Theodosiou
- Research Group for Community Dynamics, Max Planck Institute for Evolutionary Biology, August-Thienemann-Straße 2, 24306 Plön, Germany
| | - Roula Zahab
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS), Université de Montpellier-Université Paul-Valéry Montpellier-École Pratique des Hautes Études, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Thomas Lenormand
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS), Université de Montpellier-Université Paul-Valéry Montpellier-École Pratique des Hautes Études, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
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11
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Lenormand T, Engelstädter J, Johnston SE, Wijnker E, Haag CR. Evolutionary mysteries in meiosis. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2016.0001. [PMID: 27619705 DOI: 10.1098/rstb.2016.0001] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2016] [Indexed: 01/25/2023] Open
Abstract
Meiosis is a key event of sexual life cycles in eukaryotes. Its mechanistic details have been uncovered in several model organisms, and most of its essential features have received various and often contradictory evolutionary interpretations. In this perspective, we present an overview of these often 'weird' features. We discuss the origin of meiosis (origin of ploidy reduction and recombination, two-step meiosis), its secondary modifications (in polyploids or asexuals, inverted meiosis), its importance in punctuating life cycles (meiotic arrests, epigenetic resetting, meiotic asymmetry, meiotic fairness) and features associated with recombination (disjunction constraints, heterochiasmy, crossover interference and hotspots). We present the various evolutionary scenarios and selective pressures that have been proposed to account for these features, and we highlight that their evolutionary significance often remains largely mysterious. Resolving these mysteries will likely provide decisive steps towards understanding why sex and recombination are found in the majority of eukaryotes.This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'.
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Affiliation(s)
- Thomas Lenormand
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS), Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Jan Engelstädter
- School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Susan E Johnston
- Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK
| | - Erik Wijnker
- Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS), Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), 1919 Route de Mende, 34293 Montpellier Cedex 5, France
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12
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Svendsen N, Reisser CMO, Dukić M, Thuillier V, Ségard A, Liautard-Haag C, Fasel D, Hürlimann E, Lenormand T, Galimov Y, Haag CR. Uncovering Cryptic Asexuality in Daphnia magna by RAD Sequencing. Genetics 2015; 201:1143-55. [PMID: 26341660 PMCID: PMC4649641 DOI: 10.1534/genetics.115.179879] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/29/2015] [Indexed: 02/06/2023] Open
Abstract
The breeding systems of many organisms are cryptic and difficult to investigate with observational data, yet they have profound effects on a species' ecology, evolution, and genome organization. Genomic approaches offer a novel, indirect way to investigate breeding systems, specifically by studying the transmission of genetic information from parents to offspring. Here we exemplify this method through an assessment of self-fertilization vs. automictic parthenogenesis in Daphnia magna. Self-fertilization reduces heterozygosity by 50% compared to the parents, but under automixis, whereby two haploid products from a single meiosis fuse, the expected heterozygosity reduction depends on whether the two meiotic products are separated during meiosis I or II (i.e., central vs. terminal fusion). Reviewing the existing literature and incorporating recombination interference, we derive an interchromosomal and an intrachromosomal prediction of how to distinguish various forms of automixis from self-fertilization using offspring heterozygosity data. We then test these predictions using RAD-sequencing data on presumed automictic diapause offspring of so-called nonmale producing strains and compare them with "self-fertilized" offspring produced by within-clone mating. The results unequivocally show that these offspring were produced by automixis, mostly, but not exclusively, through terminal fusion. However, the results also show that this conclusion was only possible owing to genome-wide heterozygosity data, with phenotypic data as well as data from microsatellite markers yielding inconclusive or even misleading results. Our study thus demonstrates how to use the power of genomic approaches for elucidating breeding systems, and it provides the first demonstration of automictic parthenogenesis in Daphnia.
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Affiliation(s)
- Nils Svendsen
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France
| | - Celine M O Reisser
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Marinela Dukić
- Zoology Institute, Evolutionary Biology, University of Basel, 4051 Basel, Switzerland
| | - Virginie Thuillier
- Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Adeline Ségard
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France
| | | | - Dominique Fasel
- Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Evelin Hürlimann
- Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
| | - Thomas Lenormand
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France
| | - Yan Galimov
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Christoph R Haag
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)-Unité Mixte de Recherche 5175, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier-Université Paul-Valéry Montpellier-Ecole Pratique des Hautes Etudes (EPHE), campus CNRS, 19, 34293 Montpellier Cedex 5, France Ecology and Evolution, University of Fribourg, 1700 Fribourg, Switzerland
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13
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Hood ME, Scott M, Hwang M. Breaking linkage between mating compatibility factors: Tetrapolarity in Microbotryum. Evolution 2015; 69:2561-72. [PMID: 26339889 DOI: 10.1111/evo.12765] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 08/02/2015] [Indexed: 12/31/2022]
Abstract
Linkage of genes determining separate self-incompatibility mechanisms is a general expectation of sexual eukaryotes that helps to resolve conflicts between reproductive assurance and recombination. However, in some organisms, multiple loci are required to be heterozygous in offspring while segregating independently in meiosis. This condition, termed "tetrapolarity" in basidiomycete fungi, originated in the ancestor to that phylum, and there have been multiple reports of subsequent transitions to "bipolarity" (i.e., linkage of separate mating factors). In the genus Microbotryum, we present the first report of the breaking of linkage between two haploid self-incompatibility factors and derivation of a tetrapolar breeding system. This breaking of linkage is associated with major alteration of genome structure, with the compatibility factors residing on separate mating-type chromosome pairs, reduced in size but retaining the structural dimorphism characteristic for regions of recombination suppression. The challenge to reproductive assurance from unlinked compatibility factors may be overcome by the automictic mating system in Microbotryum (i.e., mating among products of the same meiosis). As a curious outcome, this linkage transition and its effects upon outcrossing compatibility rates may reinforce automixis as a mating system. These observations contribute to understanding mating systems and linkage as fundamental principles of sexual life cycles, with potential impacts on conventional wisdom regarding mating-type evolution.
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Affiliation(s)
- Michael E Hood
- Department of Biology, Amherst College, Amherst, Massachusetts, 01002.
| | - Molly Scott
- Department of Biology, Amherst College, Amherst, Massachusetts, 01002
| | - Mindy Hwang
- Department of Biology, Amherst College, Amherst, Massachusetts, 01002
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Kawatsu K. Sexual conflict over the maintenance of sex: effects of sexually antagonistic coevolution for reproductive isolation of parthenogenesis. PLoS One 2013; 8:e58141. [PMID: 23469150 PMCID: PMC3585248 DOI: 10.1371/journal.pone.0058141] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 01/31/2013] [Indexed: 11/19/2022] Open
Abstract
Sexual reproduction involves many costs. Therefore, females acquiring a capacity for parthenogenetic (or asexual) reproduction will gain a reproductive advantage over obligately sexual females. In contrast, for males, any trait coercing parthenogens into sexual reproduction (male coercion) increases their fitness and should be under positive selection because parthenogenesis deprives them of their genetic contribution to future generations. Surprisingly, although such sexual conflict is a possible outcome whenever reproductive isolation is incomplete between parthenogens and the sexual ancestors, it has not been given much attention in the studies of the maintenance of sex. Using two mathematical models, I show here that the evolution of male coercion substantially favours the maintenance of sex even though a female barrier against the coercion can evolve. First, the model based on adaptive-dynamics theory demonstrates that the resultant antagonistic coevolution between male coercion and a female barrier fundamentally ends in either the prevalence of sex or the co-occurrence of two reproductive modes. This is because the coevolution between the two traits additionally involves sex-ratio selection, that is, an increase in parthenogenetic reproduction leads to a female-biased population sex ratio, which will enhance reproductive success of more coercive males and directly promotes the evolution of the coercion among males. Therefore, as shown by the individual-based model, the establishment of obligate parthenogenesis in the population requires the simultaneous evolution of strong reproductive isolation between males and parthenogens. These findings should shed light on the interspecific diversity of reproductive modes as well as help to explain the prevalence of sexual reproduction.
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Affiliation(s)
- Kazutaka Kawatsu
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawaoiwake-cho, Sakyo-ku, Kyoto, Japan.
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15
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Abstract
Genomic regions that determine mating compatibility are subject to distinct evolutionary forces that can lead to a cessation of meiotic recombination and the accumulation of structural changes between members of the homologous chromosome pair. The relatively recent discovery of dimorphic mating-type chromosomes in fungi can aid the understanding of sex chromosome evolution that is common to dioecious plants and animals. For the anther-smut fungus, Microbotryum lychnidis-dioicae (= M. violaceum isolated from Silene latifolia), the extent of recombination cessation on the dimorphic mating-type chromosomes has been conflictingly reported. Comparison of restriction digest optical maps for the two mating-type chromosomes shows that divergence extends over 90% of the chromosome lengths, flanked at either end by two pseudoautosomal regions. Evidence to support the expansion of recombination cessation in stages from the mating-type locus toward the pseudoautosomal regions was not found, but evidence of such expansion could be obscured by ongoing processes that affect genome structure. This study encourages the comparison of forces that may drive large-scale recombination suppression in fungi and other eukaryotes characterized by dimorphic chromosome pairs associated with sexual life cycles.
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Reynolds RG, Booth W, Schuett GW, Fitzpatrick BM, Burghardt GM. Successive virgin births of viable male progeny in the checkered gartersnake,Thamnophis marcianus. Biol J Linn Soc Lond 2012. [DOI: 10.1111/j.1095-8312.2012.01954.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- R. Graham Reynolds
- Department of Ecology and Evolutionary Biology; University of Tennessee; 569 Dabney Hall Knoxville TN 37996-1610 USA
| | - Warren Booth
- Department of Entomology; W. M. Keck Center for Behavioral Biology; North Carolina State University; Box 7613 Raleigh NC 27695 USA
| | - Gordon W. Schuett
- Department of Biology; Center for Behavioral Neuroscience; Georgia State University; 33 Gilmer Street, SE, Unit 8 Atlanta GA 30303-3088 USA
| | - Benjamin M. Fitzpatrick
- Department of Ecology and Evolutionary Biology; University of Tennessee; 569 Dabney Hall Knoxville TN 37996-1610 USA
| | - Gordon M. Burghardt
- Department of Ecology and Evolutionary Biology; University of Tennessee; 569 Dabney Hall Knoxville TN 37996-1610 USA
- Department of Psychology; University of Tennessee; 1404 Circle Drive Knoxville TN 37996-0900 USA
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17
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Meirmans S, Meirmans PG, Kirkendall LR. The costs of sex: facing real-world complexities. QUARTERLY REVIEW OF BIOLOGY 2012; 87:19-40. [PMID: 22518931 DOI: 10.1086/663945] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Understanding the maintenance of sexual reproduction constitutes a difficult problem for evolutionary biologists because of the immediate costs that sex seems to incur. Typically, general benefits to sex and recombination are investigated that might outweigh these costs. However, several factors can strongly influence the complex balance between costs and benefits of sex; these include constraints on the evolution of asexuality, ecological differentiation, and certain lif-history traits. We review these factors and their empirical support for the first time in a unified framework and find that they can reduce the costs of sex, circumvent them, or make them inapplicable. These factors can even tip the scales to a net benefit for sex. The reviewed factors affect species and species groups differently, and we conclude consequently that understanding the maintenance of sex could turn out to be more species-specific than commonly assumed. Interestingly, our study suggests that, in some species, no general benefits to sex and recombination might be needed to understand the maintenance of sex, as in our case study of dandelions.
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Affiliation(s)
- Stephanie Meirmans
- Centre for the Study of the Sciences and the Humanities and Department of Biology, University of Bergen 5020 Bergen, Norway.
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18
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Billiard S, López-Villavicencio M, Hood ME, Giraud T. Sex, outcrossing and mating types: unsolved questions in fungi and beyond. J Evol Biol 2012; 25:1020-38. [PMID: 22515640 DOI: 10.1111/j.1420-9101.2012.02495.x] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Variability in the way organisms reproduce raises numerous, and still unsolved, questions in evolutionary biology. In this study, we emphasize that fungi deserve a much greater emphasis in efforts to address these questions because of their multiple advantages as model eukaryotes. A tremendous diversity of reproductive modes and mating systems can be found in fungi, with many evolutionary transitions among closely related species. In addition, fungi show some peculiarities in their mating systems that have received little attention so far, despite the potential for providing insights into important evolutionary questions. In particular, selfing can occur at the haploid stage in addition to the diploid stage in many fungi, which is generally not possible in animals and plants but has a dramatic influence upon the structure of genetic systems. Fungi also present several advantages that make them tractable models for studies in experimental evolution. Here, we briefly review the unsolved questions and extant hypotheses about the evolution and maintenance of asexual vs. sexual reproduction and of selfing vs. outcrossing, focusing on fungal life cycles. We then propose how fungi can be used to address these long-standing questions and advance our understanding of sexual reproduction and mating systems across all eukaryotes.
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Affiliation(s)
- S Billiard
- Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, Villeneuve d'Ascq Cedex, France.
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19
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The many costs of sex. Trends Ecol Evol 2012; 27:172-8. [DOI: 10.1016/j.tree.2011.09.016] [Citation(s) in RCA: 221] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Revised: 09/22/2011] [Accepted: 09/23/2011] [Indexed: 11/24/2022]
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BOOTH WARREN, SCHUETT GORDONW. Molecular genetic evidence for alternative reproductive strategies in North American pitvipers (Serpentes: Viperidae): long-term sperm storage and facultative parthenogenesis. Biol J Linn Soc Lond 2011. [DOI: 10.1111/j.1095-8312.2011.01782.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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Masel J, Lyttle DN. The consequences of rare sexual reproduction by means of selfing in an otherwise clonally reproducing species. Theor Popul Biol 2011; 80:317-22. [PMID: 21888925 DOI: 10.1016/j.tpb.2011.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 08/16/2011] [Accepted: 08/17/2011] [Indexed: 11/29/2022]
Abstract
Clonal reproduction of diploids leads to an increase in heterozygosity over time. A single round of selfing will then create new homozygotic genotypes. Given the same allele frequencies, heritable genetic variation is larger when there are more extreme, i.e. homozygotic genotypes. So after a long clonal expansion, one round of selfing increases heritable genetic variation, but any fully or partially recessive deleterious alleles simultaneously impose a fitness cost. Here we calculate that the cost of selfing in the yeast Saccharomyces is experienced only by a minority of zygotes. This allows a round of selfing to act as an evolutionary capacitor to unlock genetic variation previously found in a cryptic heterozygous form. We calculate the evolutionary consequences rather than the evolutionary causes of sex. We explore a range of parameter values describing sexual frequencies, focusing especially on the parameter values known for wild Saccharomyces. Our results are largely robust to many other parameter value choices, so long as meiosis is rare relative to the strength of selection on heterozygotes. Results may also be limited to organisms with a small number of genes. We therefore expect the same phenomenon in some other species with similar reproductive strategies.
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Affiliation(s)
- Joanna Masel
- Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA.
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22
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Buřič M, Hulák M, Kouba A, Petrusek A, Kozák P. A successful crayfish invader is capable of facultative parthenogenesis: a novel reproductive mode in decapod crustaceans. PLoS One 2011; 6:e20281. [PMID: 21655282 PMCID: PMC3105005 DOI: 10.1371/journal.pone.0020281] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Accepted: 04/27/2011] [Indexed: 11/30/2022] Open
Abstract
Biological invasions are impacting biota worldwide, and explaining why some taxa tend to become invasive is of major scientific interest. North American crayfish species, particularly of the family Cambaridae, are prominent invaders in freshwaters, defying the “tens rule” which states that only a minority of species introduced to new regions become established, and only a minority of those become invasive and pests. So far, success of cambarid invaders has largely been attributed to rapid maturation, high reproductive output, aggressiveness, and tolerance to pollution. We provide experimental evidence that females of one cambarid species particularly widespread in Europe, the spiny-cheek crayfish Orconectes limosus, are capable of facultative parthenogenesis. Such reproductive mode has never before been recognized in decapods, the most diverse crustacean order. As shown by analysis of seven microsatellite loci, crayfish females kept physically separated from males produced genetically homogeneous offspring identical with maternal individuals; this suggests they reproduced by apomixis, unlike those females which mated with males and had a diverse offspring. Further research is needed to clarify what environmental conditions are necessary for a switch to parthenogenesis in O. limosus, and what role it plays in natural crayfish populations. However, if such reproductive plasticity is present in other cambarid crayfish species, it may contribute to the overwhelming invasive success of this group.
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Affiliation(s)
- Miloš Buřič
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses and Research Institute of Fish Culture and Hydrobiology, University of South Bohemia in Èeské Budìjovice, Vodòany, Czech Republic.
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23
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Johnson CH. Effects of selfing on offspring survival and reproduction in a colonial simultaneous hermaphrodite (Bugula stolonifera, Bryozoa). THE BIOLOGICAL BULLETIN 2010; 219:27-37. [PMID: 20813987 DOI: 10.1086/bblv219n1p27] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Understanding the consequences of selfing in simultaneous hermaphrodites requires investigating potential deleterious effects on fitness at all stages of life. In this study, I examined the effects of selfing throughout the life cycle of the marine bryozoan Bugula stolonifera, a colonial simultaneous hermaphrodite. In 2008, larvae from field-collected colonies were cultured through metamorphosis to reproductively mature colonies either in the presence of one other colony, the paired treatment, or alone, the solitary treatment. Results demonstrated that selfing in this species is possible, in that colonies in the solitary treatment produced viable larvae that successfully completed metamorphosis. On average, however, these colonies released significantly fewer larvae, which experienced reduced rates of metamorphic initiation and completion compared to the paired treatment. These experiments were extended in 2009, when metamorphs from colonies reared in the solitary (n = 58) and paired (n = 61) treatments were transferred to the field for growth to reproductive maturity and then brought back to the laboratory for larval collection. Results revealed additional deleterious effects associated with selfing, as no viable larvae were recovered from colonies deriving from the solitary treatment. In contrast, offspring from the paired treatment released 1030 larvae and 99% initiated metamorphosis, 97% of which completed metamorphosis. Overall, selfed larvae not only had significantly decreased chances of survival, but those that did survive did not successfully reproduce.
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Affiliation(s)
- Collin H Johnson
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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24
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BACKELJAU THIERRY, WINTER ANTONJDE, MARTIN RAMON, RODRIGUEZ TERESA, BRUYN LUCDE. Genital and allozyme similarity between Arion urbiae and A. anguloi (Mollusca: Pulmonata). Zool J Linn Soc 2008. [DOI: 10.1111/j.1096-3642.1994.tb01467.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Dick MW. Sexual reproduction: nuclear cycles and life-histories with particular reference to lower eukaryotes. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.1987.tb00296.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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27
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Lampert KP, Lamatsch DK, Fischer P, Epplen JT, Nanda I, Schmid M, Schartl M. Automictic Reproduction in Interspecific Hybrids of Poeciliid Fish. Curr Biol 2007; 17:1948-53. [DOI: 10.1016/j.cub.2007.09.064] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 09/26/2007] [Accepted: 09/27/2007] [Indexed: 10/22/2022]
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28
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Thompson SL, Ritland K. A novel mating system analysis for modes of self-oriented mating applied to diploid and polyploid arctic Easter daisies (Townsendia hookeri). Heredity (Edinb) 2006; 97:119-26. [PMID: 16721390 DOI: 10.1038/sj.hdy.6800844] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We have developed a new model for mating system analysis, which attempts to distinguish among alternative modes of self-oriented mating within populations. This model jointly estimates the rates of outcrossing, selfing, automixis and apomixis, through the use of information in the family structure given by dominant genetic marker data. The method is presented, its statistical properties evaluated, and is applied to three arctic Easter daisy populations, one consisting of diploids, the other two of tetraploids. The tetraploids are predominantly male sterile and reported to be apomictic while the diploids are male fertile. In each Easter daisy population, 10 maternal arrays of six progeny were assayed for amplified fragment length polymorphism markers. Estimates, confirmed with likelihood ratio tests of mating hypotheses, showed apomixis to be predominant in all populations (ca. 70%), but selfing or automixis was moderate (ca. 25%) in tetraploids. It was difficult to distinguish selfing from automixis, and simulations confirm that with even very large sample sizes, the estimates have a very strong negative statistical correlation, for example, they are not independent. No selfing or automixis was apparent in the diploid population, instead, moderate levels of outcrossing were detected (23%). Low but significant levels of outcrossing (2-4%) seemed to occur in the male-sterile tetraploid populations; this may be due to genotyping error of this level. Overall, this study shows apomixis can be partial, and provides evidence for higher levels of inbreeding in polyploids compared to diploids and for significant levels of apomixis in a diploid plant population.
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Affiliation(s)
- S L Thompson
- Department of Botany and Centre for Biodiversity Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
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30
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Abstract
Mating among the immediate products of meiosis (intratetrad mating) is a common feature of many organisms with parthenogenesis or with mating-type determination in the haploid phase. Using a three-locus deterministic model we show that intratetrad mating, unlike other systems of mating, allows sheltering of deleterious recessive alleles even if there is only partial linkage between a mating locus and a load locus. Moreover, modifiers that reduce recombination between the load and mating-type locus will spread to fixation, even when there is no linkage disequilibrium between these loci in the population as a whole. This seeming contradiction to classical expectation is because partial linkage generates linkage disequilibrium among segregating loci within a tetrad, which then acts as the "mating unit."
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Affiliation(s)
- Janis Antonovics
- Department of Biology, University of Virginia, Charlottesville, Virginia 22904, USA.
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31
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Jordaens K, Scheirs J, Verhagen R, Backeljau T. Ecogenetic Comparison of the Selfing Terrestrial Slugs Arion Silvaticus and A. Circumscriptus in Belgium (Mollusca: Pulmonata: Arionidae). Hereditas 2004. [DOI: 10.1111/j.1601-5223.1998.00027.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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32
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Hood ME, Antonovics J. Mating Within the Meiotic Tetrad and the Maintenance of Genomic Heterozygosity. Genetics 2004. [DOI: 10.1093/genetics/166.4.1751] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Mating among the products of a single meiosis (automixis or meiotic parthenogenesis) is found in diverse groups of plant, animal, and fungal taxa. Restoration of the diploid stage is often strictly controlled and brings together products separated at the first meiotic division. Despite apparent similarities to diploid selfing, the theoretical prediction is that heterozygosity should be maintained on all chromosomes when it is linked to the centromeres and thus also segregates at the first meiotic division. Using the fungus Microbotryum, we directly test this prediction by linear tetrad analysis. The patterns of meiotic segregation for chromosome size variation (electrophoretic karyotypes) and PCR products (AFLP procedures) were determined for Microbotryum lineages native to North America and Europe. Our data reveal a surprisingly dynamic genome that is rich in heterozygosity and where size-dimorphic autosomes are common. The genetic variation agrees with the prediction of centromere-linked heterozygosity. This was observed to the greatest extent in the lineage of Microbotryum native to North America where there was consistent first-division segregation and independent assortment of multiple linkage groups. The data also show properties that distinguish the fungal sex chromosomes from the autosomes in both lineages of Microbotryum. We describe a scenario where the mating system of automixis with first-division restitution is the result of feedback mechanisms to control exposure of genetic load.
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Affiliation(s)
- Michael E Hood
- Department of Biology, University of Virginia, Charlottesville, Virginia 22903
| | - Janis Antonovics
- Department of Biology, University of Virginia, Charlottesville, Virginia 22903
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33
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Antonovics J, Abrams JY. INTRATETRAD MATING AND THE EVOLUTION OF LINKAGE RELATIONSHIPS. Evolution 2004. [DOI: 10.1554/02-521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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34
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NORMARK BENJAMINB, JUDSON OLIVIAP, MORAN NANCYA. Genomic signatures of ancient asexual lineages. Biol J Linn Soc Lond 2003. [DOI: 10.1046/j.1095-8312.2003.00182.x] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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35
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Jordaens K, Backeljau T, Ondina P, Reise H, Verhagen R. Allozyme homozygosity and phally polymorphism in the land snail Zonitoides nitidus (Gastropoda, Pulmonata). J Zool (1987) 1998. [DOI: 10.1111/j.1469-7998.1998.tb00137.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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36
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Affiliation(s)
- Alexey S. Kondrashov
- Section of Ecology and Systematics, Cornell University, Ithaca, New York; 14853 e-mail:
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37
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38
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39
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Mogie M. HOMOSPORY AND THE COST OF ASEXUAL REPRODUCTION. Evolution 1990; 44:1707-1710. [PMID: 28564314 DOI: 10.1111/j.1558-5646.1990.tb03858.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/1989] [Accepted: 12/22/1989] [Indexed: 11/28/2022]
Affiliation(s)
- Michael Mogie
- School of Biological Sciences, University of Bath, Claverton Down, Bath BA2 7AY, U.K
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40
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Bilinski CA, Marmiroli N, Miller JJ. Apomixis in Saccharomyces cerevisiae and other eukaryotic micro-organisms. Adv Microb Physiol 1990; 30:23-52. [PMID: 2700540 DOI: 10.1016/s0065-2911(08)60109-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- C A Bilinski
- Research Department, Labatt Brewing Company Limited, London, Ontario, Canada
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41
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