1
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Haag CR. Loss of sex in brown algae. Nat Ecol Evol 2024:10.1038/s41559-024-02497-3. [PMID: 39152326 DOI: 10.1038/s41559-024-02497-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2024]
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2
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Hoshino M, Cossard G, Haas FB, Kane EI, Kogame K, Jomori T, Wakimoto T, Glemin S, Coelho SM. Parallel loss of sexual reproduction in field populations of a brown alga sheds light on the mechanisms underlying the emergence of asexuality. Nat Ecol Evol 2024:10.1038/s41559-024-02490-w. [PMID: 39152327 DOI: 10.1038/s41559-024-02490-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 06/18/2024] [Indexed: 08/19/2024]
Abstract
Sexual reproduction is widespread, but asexual lineages have repeatedly arisen from sexual ancestors across a wide range of eukaryotic taxa. The molecular changes underpinning the switch to asexuality remain elusive, particularly in organisms with haploid sexual systems. Here we explore independent events of loss of sex in the brown alga Scytosiphon, examine the proximate and evolutionary mechanisms involved, and test the importance of sexual conflict on gene expression changes following loss of sex. We find that asexual females ('Amazons') lose ability to produce sex pheromone and, consequently, are incapable of attracting males, whereas they gain rapid parthenogenic development from large, unfertilized eggs. These phenotypic changes are accompanied by convergent changes in gene expression. Decay of female functions, rather than relaxation of sexual antagonism, may be a dominant force at play during the emergence of asexuality in haploid sexual systems. Moreover, we show that haploid purifying selection plays a key role in limiting the accumulation of deleterious alleles in Amazons, and we identify an autosomal locus associated with the Amazon phenotype. The sex chromosome, together with this autosomal locus, may underlie the switch to obligate asexuality in the Amazon populations.
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Affiliation(s)
- Masakazu Hoshino
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
- Research Center for Inland Seas, Kobe University, Rokkodai 1-1, Nadaku, Kobe, Japan
| | - Guillaume Cossard
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Fabian B Haas
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Emma I Kane
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Kazuhiro Kogame
- Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, Japan
| | - Takahiro Jomori
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | | | - Sylvain Glemin
- Laboratoire ECOBIO (Ecosystèmes, biodiversité, évolution), UMR 6553, CNRS, Université de Rennes, Rennes, France
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Susana M Coelho
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany.
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3
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Jay P, Jeffries D, Hartmann FE, Véber A, Giraud T. Why do sex chromosomes progressively lose recombination? Trends Genet 2024; 40:564-579. [PMID: 38677904 DOI: 10.1016/j.tig.2024.03.005] [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: 10/17/2023] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/29/2024]
Abstract
Progressive recombination loss is a common feature of sex chromosomes. Yet, the evolutionary drivers of this phenomenon remain a mystery. For decades, differences in trait optima between sexes (sexual antagonism) have been the favoured hypothesis, but convincing evidence is lacking. Recent years have seen a surge of alternative hypotheses to explain progressive extensions and maintenance of recombination suppression: neutral accumulation of sequence divergence, selection of nonrecombining fragments with fewer deleterious mutations than average, sheltering of recessive deleterious mutations by linkage to heterozygous alleles, early evolution of dosage compensation, and constraints on recombination restoration. Here, we explain these recent hypotheses and dissect their assumptions, mechanisms, and predictions. We also review empirical studies that have brought support to the various hypotheses.
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Affiliation(s)
- Paul Jay
- Center for GeoGenetics, University of Copenhagen, Copenhagen, Denmark; Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France.
| | - Daniel Jeffries
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland
| | - Fanny E Hartmann
- Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France
| | - Amandine Véber
- Université Paris Cité, CNRS, MAP5, F-75006 Paris, France
| | - Tatiana Giraud
- Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France
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4
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Krueger-Hadfield SA. Let's talk about sex: Why reproductive systems matter for understanding algae. JOURNAL OF PHYCOLOGY 2024; 60:581-597. [PMID: 38743848 DOI: 10.1111/jpy.13462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/16/2024]
Abstract
Sex is a crucial process that has molecular, genetic, cellular, organismal, and population-level consequences for eukaryotic evolution. Eukaryotic life cycles are composed of alternating haploid and diploid phases but are constrained by the need to accommodate the phenotypes of these different phases. Critical gaps in our understanding of evolutionary drivers of the diversity in algae life cycles include how selection acts to stabilize and change features of the life cycle. Moreover, most eukaryotes are partially clonal, engaging in both sexual and asexual reproduction. Yet, our understanding of the variation in their reproductive systems is largely based on sexual reproduction in animals or angiosperms. The relative balance of sexual versus asexual reproduction not only controls but also is in turn controlled by standing genetic variability, thereby shaping evolutionary trajectories. Thus, we must quantitatively assess the consequences of the variation in life cycles on reproductive systems. Algae are a polyphyletic group spread across many of the major eukaryotic lineages, providing powerful models by which to resolve this knowledge gap. There is, however, an alarming lack of data about the population genetics of most algae and, therefore, the relative frequency of sexual versus asexual processes. For many algae, the occurrence of sexual reproduction is unknown, observations have been lost in overlooked papers, or data on population genetics do not yet exist. This greatly restricts our ability to forecast the consequences of climate change on algal populations inhabiting terrestrial, aquatic, and marine ecosystems. This perspective summarizes our extant knowledge and provides some future directions to pursue broadly across micro- and macroalgal species.
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5
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Luthringer R, Raphalen M, Guerra C, Colin S, Martinho C, Zheng M, Hoshino M, Badis Y, Lipinska AP, Haas FB, Barrera-Redondo J, Alva V, Coelho SM. Repeated co-option of HMG-box genes for sex determination in brown algae and animals. Science 2024; 383:eadk5466. [PMID: 38513029 DOI: 10.1126/science.adk5466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 01/31/2024] [Indexed: 03/23/2024]
Abstract
In many eukaryotes, genetic sex determination is not governed by XX/XY or ZW/ZZ systems but by a specialized region on the poorly studied U (female) or V (male) sex chromosomes. Previous studies have hinted at the existence of a dominant male-sex factor on the V chromosome in brown algae, a group of multicellular eukaryotes distantly related to animals and plants. The nature of this factor has remained elusive. Here, we demonstrate that an HMG-box gene acts as the male-determining factor in brown algae, mirroring the role HMG-box genes play in sex determination in animals. Over a billion-year evolutionary timeline, these lineages have independently co-opted the HMG box for male determination, representing a paradigm for evolution's ability to recurrently use the same genetic "toolkit" to accomplish similar tasks.
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Affiliation(s)
- Rémy Luthringer
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Morgane Raphalen
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Carla Guerra
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Sébastien Colin
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Claudia Martinho
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Min Zheng
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Masakazu Hoshino
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
- Research Center for Inland Seas, Kobe University, Kobe 658-0022, Japan
| | - Yacine Badis
- Roscoff Biological Station, CNRS-Sorbonne University, Place Georges Teissier, 29680 Roscoff, France
| | - Agnieszka P Lipinska
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Fabian B Haas
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Josué Barrera-Redondo
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Vikram Alva
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
| | - Susana M Coelho
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, 72076 Tübingen, Germany
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Choi SW, Graf L, Choi JW, Jo J, Boo GH, Kawai H, Choi CG, Xiao S, Knoll AH, Andersen RA, Yoon HS. Ordovician origin and subsequent diversification of the brown algae. Curr Biol 2024; 34:740-754.e4. [PMID: 38262417 DOI: 10.1016/j.cub.2023.12.069] [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: 11/06/2023] [Revised: 12/08/2023] [Accepted: 12/20/2023] [Indexed: 01/25/2024]
Abstract
Brown algae are the only group of heterokont protists exhibiting complex multicellularity. Since their origin, brown algae have adapted to various marine habitats, evolving diverse thallus morphologies and gamete types. However, the evolutionary processes behind these transitions remain unclear due to a lack of a robust phylogenetic framework and problems with time estimation. To address these issues, we employed plastid genome data from 138 species, including heterokont algae, red algae, and other red-derived algae. Based on a robust phylogeny and new interpretations of algal fossils, we estimated the geological times for brown algal origin and diversification. The results reveal that brown algae first evolved true multicellularity, with plasmodesmata and reproductive cell differentiation, during the late Ordovician Period (ca. 450 Ma), coinciding with a major diversification of marine fauna (the Great Ordovician Biodiversification Event) and a proliferation of multicellular green algae. Despite its early Paleozoic origin, the diversification of major orders within this brown algal clade accelerated only during the Mesozoic Era, coincident with both Pangea rifting and the diversification of other heterokont algae (e.g., diatoms), coccolithophores, and dinoflagellates, with their red algal-derived plastids. The transition from ancestral isogamy to oogamy was followed by three simultaneous reappearances of isogamy during the Cretaceous Period. These are concordant with a positive character correlation between parthenogenesis and isogamy. Our new brown algal timeline, combined with a knowledge of past environmental conditions, shed new light on brown algal diversification and the intertwined evolution of multicellularity and sexual reproduction.
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Affiliation(s)
- Seok-Wan Choi
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Louis Graf
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea; Institut de Biologie de l'École Normale Supérieure, Université Paris Sciences et Lettres, Paris 75005, France
| | - Ji Won Choi
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jihoon Jo
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea; Honam National Institute of Biological Resources, Mokpo 58762, Republic of Korea
| | - Ga Hun Boo
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hiroshi Kawai
- Kobe University Research Center for Inland Seas, Rokkodai, Nadaku, Kobe 657-8501, Japan
| | - Chang Geun Choi
- Department of Ecological Engineering, College of Environmental and Marine Technology, Pukyong National University, Busan 48513, Republic of Korea
| | - Shuhai Xiao
- Department of Geosciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Andrew H Knoll
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Robert A Andersen
- Friday Harbor Laboratories, University of Washington, Seattle, WA 98250, USA
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea.
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7
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De Clerck O, LoDuca ST. Algal evolution: A touch of brown in a Paleozoic sea of greens and reds. Curr Biol 2024; 34:R150-R152. [PMID: 38412826 DOI: 10.1016/j.cub.2024.01.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
Previous molecular clock studies indicated a Mesozoic origin for the brown algae (Phaeophyceae). New research based on phylogenetic evidence challenges this notion and provides novel insights into the origin and diversification of brown algae, which includes multiple transitions within the group from isogamy to oogamy (and back again!).
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Affiliation(s)
- Olivier De Clerck
- Phycology Research Group and Center for Molecular Phylogenetics and Evolution, Ghent University, Ghent 9000, Belgium.
| | - Steven T LoDuca
- Department of Geography and Geology, Eastern Michigan University, Ypsilanti, MI 48197, USA.
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8
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Bodar PA, Thakur RS, Rajai JV, Bhushan S, Mantri VA. A metabolomic snapshot through NMR revealed differences in phase transition during the induction of reproduction in Ulva ohnoi (Chlorophyta). Mol Omics 2024; 20:86-102. [PMID: 38239131 DOI: 10.1039/d3mo00197k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
The present study deals with the metabolomic status of Ulva cells undergoing phase transition (vegetative, determination and differentiation) when exposed to different abiotic conditions. The objective was to study whether metabolite changes occurring during the phase transition reveal any commonality among differential abiotic conditions. The phase transition was followed through microscopic observations and 1H NMR characterization at 0 h, 24 h, and 48 h after the incubation of the thallus under abiotic conditions, such as different salinities (20-35 psu), temperatures (20-35 °C), photoperiods (18 : 6, 12 : 12, and 6 : 18 D/N), light intensities (220, 350, and 500 μmol photons m-2 s-1), nitrate (0.05-0.2 g L-1) and phosphate (0.05-0.2 g L-1) concentrations. Microscopic analysis revealed the role of all abiotic conditions except variable salinity and phosphate concentration in phase transition. NMR analysis revealed that glucose increased in the determination phase [7.58 to 9.62 normalized intensity (AU)] and differentiation phase (5.85 to 6.41 AU) from 20 °C to 25 °C temperature. Coniferyl aldehyde increased in vegetative (5.79 to 6.83 AU) and differentiation (6.66 to 7.40 AU) phases from 20 °C to 30 °C temperature. The highest average (22.97) was found in photoperiod (average range = 0-122.91) and the highest SD (24.73) in salinity (SD range = 1.86-57.04) in region 9 (creatinine and cysteine) of the differentiation phase. A total of 30 metabolites were identified under the categories of sugars, amino acids, and aromatic compounds. The present study will aid in understanding the mechanisms underlying cell differentiation during reproduction. The result may serve as an important reference point for future studies, besides helping in controlling seedling preparation for commercial farming as well as the management of rapid green tide formation.
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Affiliation(s)
- Payal A Bodar
- Applied Phycology and Biotechnology Division, CSIR- Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Road, Bhavnagar - 364002, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad - 201002, India
| | - Rajendra Singh Thakur
- Analytical and Environmental, Science Division and Centralized Instrument Facility, Bhavnagar 364002, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad - 201002, India
| | - Jasmine V Rajai
- Applied Phycology and Biotechnology Division, CSIR- Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Road, Bhavnagar - 364002, India.
| | - Satej Bhushan
- Applied Phycology and Biotechnology Division, CSIR- Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Road, Bhavnagar - 364002, India.
| | - Vaibhav A Mantri
- Applied Phycology and Biotechnology Division, CSIR- Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Road, Bhavnagar - 364002, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad - 201002, India
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9
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Takeuchi Y, Sato S, Nagasato C, Motomura T, Okuda S, Kasahara M, Takahashi F, Yoshikawa S. Sperm-specific histone H1 in highly condensed sperm nucleus of Sargassum horneri. Sci Rep 2024; 14:3387. [PMID: 38336896 PMCID: PMC10858212 DOI: 10.1038/s41598-024-53729-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 02/04/2024] [Indexed: 02/12/2024] Open
Abstract
Spermatogenesis is one of the most dramatic changes in cell differentiation. Remarkable chromatin condensation of the nucleus is observed in animal, plant, and algal sperm. Sperm nuclear basic proteins (SNBPs), such as protamine and sperm-specific histone, are involved in chromatin condensation of the sperm nucleus. Among brown algae, sperm of the oogamous Fucales algae have a condensed nucleus. However, the existence of sperm-specific SNBPs in Fucales algae was unclear. Here, we identified linker histone (histone H1) proteins in the sperm and analyzed changes in their gene expression pattern during spermatogenesis in Sargassum horneri. A search of transcriptomic data for histone H1 genes in showed six histone H1 genes, which we named ShH1.1a, ShH1b, ShH1.2, ShH1.3, ShH1.4, and ShH1.5. Analysis of SNBPs using SDS-PAGE and LC-MS/MS showed that sperm nuclei contain histone ShH1.2, ShH1.3, and ShH1.4 in addition to core histones. Both ShH1.2 and ShH1.3 genes were expressed in the vegetative thallus and the male and female receptacles (the organs producing antheridium or oogonium). Meanwhile, the ShH1.4 gene was expressed in the male receptacle but not in the vegetative thallus and female receptacles. From these results, ShH1.4 may be a sperm-specific histone H1 of S. horneri.
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Affiliation(s)
- Yu Takeuchi
- Faculty of Marine Science and Technology, Fukui Prefectural University, 1-1 Gakuencho, Obama, Fukui, 917-0003, Japan
| | - Shinya Sato
- Faculty of Marine Science and Technology, Fukui Prefectural University, 1-1 Gakuencho, Obama, Fukui, 917-0003, Japan
| | - Chikako Nagasato
- Field Science Center for Northern Biosphere, Muroran Marine Station, Hokkaido University, Muroran, 051-0013, Japan
| | - Taizo Motomura
- Field Science Center for Northern Biosphere, Muroran Marine Station, Hokkaido University, Muroran, 051-0013, Japan
| | - Shujiro Okuda
- Graduate School of Medical and Dental Science, Niigata University, 1-757 Asahimachi, Chuoku, Niigata, Niigata, 951-8501, Japan
| | - Masahiro Kasahara
- Graduate School of Life Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga, 525-8577, Japan
| | - Fumio Takahashi
- Graduate School of Life Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga, 525-8577, Japan
- Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba, 274-8510, Japan
| | - Shinya Yoshikawa
- Faculty of Marine Science and Technology, Fukui Prefectural University, 1-1 Gakuencho, Obama, Fukui, 917-0003, Japan.
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10
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Krueger-Hadfield SA, Shainker-Connelly SJ, Crowell RM, Vis ML. The eco-evolutionary importance of reproductive system variation in the macroalgae: Freshwater reds as a case study. JOURNAL OF PHYCOLOGY 2024; 60:15-25. [PMID: 37948315 DOI: 10.1111/jpy.13407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 10/15/2023] [Accepted: 10/18/2023] [Indexed: 11/12/2023]
Abstract
The relative frequency of sexual versus asexual reproduction governs the distribution of genetic diversity within and among populations. Most studies on the consequences of reproductive variation focus on the mating system (i.e., selfing vs. outcrossing) of diploid-dominant taxa (e.g., angiosperms), often ignoring asexual reproduction. Although reproductive systems are hypothesized to be correlated with life-cycle types, variation in the relative rates of sexual and asexual reproduction remains poorly characterized across eukaryotes. This is particularly true among the three major lineages of macroalgae (green, brown, and red). The Rhodophyta are particularly interesting, as many taxa have complex haploid-diploid life cycles that influence genetic structure. Though most marine reds have separate sexes, we show that freshwater red macroalgae exhibit patterns of switching between monoicy and dioicy in sister taxa that rival those recently shown in brown macroalgae and in angiosperms. We advocate for the investigation of reproductive system evolution using freshwater reds, as this will expand the life-cycle types for which these data exist, enabling comparative analyses broadly across eukaryotes. Unlike their marine cousins, species in the Batrachospermales have macroscopic gametophytes attached to filamentous, often microscopic sporophytes. While asexual reproduction through monospores may occur in all freshwater reds, the Compsopogonales are thought to be exclusively asexual. Understanding the evolutionary consequences of selfing and asexual reproduction will aid in our understanding of the evolutionary ecology of all algae and of eukaryotic evolution generally.
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Affiliation(s)
| | | | - Roseanna M Crowell
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio, USA
| | - Morgan L Vis
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio, USA
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11
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Gavrilov-Zimin IA. Ancient reproductive modes and criteria of multicellularity. COMPARATIVE CYTOGENETICS 2023; 17:195-238. [PMID: 37953852 PMCID: PMC10636606 DOI: 10.3897/compcytogen.17.109671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 10/05/2023] [Indexed: 11/14/2023]
Abstract
It is demonstrated that the initial method of fertilization in animals (Metazoa), embryophyte plants (Embryophyta), most groups of multicellular oogamous algae, oogamous and pseudoogamous multicellular fungi was internal fertilization (in the broad meaning) in/on the body of a maternal organism. Accordingly, during the bisexual process, the initial method of formation of a daughter multicellular organism in animals was viviparity, and in embryophyte plants and most groups of oogamous multicellular algae - the germination of a zygote in/on the body of maternal organism. The reproductive criteria of multicellularity are proposed and discussed. In this regard, the multicellularity is considered to subdivide terminologically into three variants: 1) protonemal, the most simple, characteristic of multicellular prokaryotes, most groups of multicellular algae and gametophytes of some higher plants; 2) siphonoseptal, found among multicellular fungi, some groups of green and yellow-green algae; 3) embryogenic, most complicated, known in all animals (Metazoa), all sporophytes and some gametophytes of higher plants (Embryophyta), charophyte green algae Charophyceae s.s., oogamous species of green and brown algae, some genera of red algae. In addition to the well-known division of reproduction methods into sexual and asexual, it is proposed to divide the reproduction of multicellular organisms into monocytic (the emergence of a new organism from one cell sexually or asexually) and polycytic (fragmentation, longitudinal / transverse division or budding based on many cells of the body of the mother organism), since these two ways have different evolutionary and ontogenetic origins.
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Affiliation(s)
- Ilya A. Gavrilov-Zimin
- Zoological Institute, Russian Academy of Sciences, Universitetskaya nab. 1, St. Petersburg, 199034, RussiaZoological Institute, Russian Academy of SciencesSt. PetersburgRussia
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12
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Krasovec M, Hoshino M, Zheng M, Lipinska AP, Coelho SM. Low Spontaneous Mutation Rate in Complex Multicellular Eukaryotes with a Haploid-Diploid Life Cycle. Mol Biol Evol 2023; 40:msad105. [PMID: 37140022 PMCID: PMC10254074 DOI: 10.1093/molbev/msad105] [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: 03/09/2023] [Revised: 04/22/2023] [Accepted: 05/01/2023] [Indexed: 05/05/2023] Open
Abstract
The spontaneous mutation rate µ is a crucial parameter to understand evolution and biodiversity. Mutation rates are highly variable across species, suggesting that µ is susceptible to selection and drift and that species life cycle and life history may impact its evolution. In particular, asexual reproduction and haploid selection are expected to affect the mutation rate, but very little empirical data are available to test this expectation. Here, we sequence 30 genomes of a parent-offspring pedigree in the model brown alga Ectocarpus sp.7, and 137 genomes of an interspecific cross of the closely related brown alga Scytosiphon to have access to the spontaneous mutation rate of representative organisms of a complex multicellular eukaryotic lineage outside animals and plants, and to evaluate the potential impact of life cycle on the mutation rate. Brown algae alternate between a haploid and a diploid stage, both multicellular and free living, and utilize both sexual and asexual reproduction. They are, therefore, excellent models to empirically test expectations of the effect of asexual reproduction and haploid selection on mutation rate evolution. We estimate that Ectocarpus has a base substitution rate of µbs = 4.07 × 10-10 per site per generation, whereas the Scytosiphon interspecific cross had µbs = 1.22 × 10-9. Overall, our estimations suggest that these brown algae, despite being multicellular complex eukaryotes, have unusually low mutation rates. In Ectocarpus, effective population size (Ne) could not entirely explain the low µbs. We propose that the haploid-diploid life cycle, combined with extensive asexual reproduction, may be additional key drivers of the mutation rate in these organisms.
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Affiliation(s)
- Marc Krasovec
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, Banyuls-sur-Mer, France
| | - Masakazu Hoshino
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Min Zheng
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Agnieszka P Lipinska
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Susana M Coelho
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
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13
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Henshaw JM, Bittlingmaier M, Schärer L. Hermaphroditic origins of anisogamy. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220283. [PMID: 36934747 PMCID: PMC10024982 DOI: 10.1098/rstb.2022.0283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/23/2022] [Indexed: 03/21/2023] Open
Abstract
Anisogamy-the size dimorphism of gametes-is the defining difference between the male and female sexual strategies. Game-theoretic thinking led to the first convincing explanation for the evolutionary origins of anisogamy in the 1970s. Since then, formal game-theoretic models have continued to refine our understanding of when and why anisogamy should evolve. Such models typically presume that the earliest anisogamous organisms had separate sexes. However, in most taxa, there is no empirical evidence to support this assumption. Here, we present a model of the coevolution of gamete size and sex allocation, which allows for anisogamy to emerge alongside either hermaphroditism or separate sexes. We show that hermaphroditic anisogamy can evolve directly from isogamous ancestors when the average size of spawning groups is small and fertilization is relatively efficient. Sex allocation under hermaphroditism becomes increasingly female-biased as group size decreases and the degree of anisogamy increases. When spawning groups are very small, our model also predicts the existence of complex isogamous organisms in which individuals allocate resources equally to two large gamete types. We discuss common, but potentially unwarranted, assumptions in the literature that could be relaxed in future models. This article is part of the theme issue 'Half a century of evolutionary games: a synthesis of theory, application and future directions'.
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Affiliation(s)
- Jonathan M. Henshaw
- Institute of Biology I, University of Freiburg, Hauptstraße 1, D-79104 Freiburg, Germany
| | - Markus Bittlingmaier
- Institute of Biology I, University of Freiburg, Hauptstraße 1, D-79104 Freiburg, Germany
- Theoretical and Experimental Ecology Station, CNRS, 2 route du CNRS, 09200 Moulis, France
| | - Lukas Schärer
- Zoological Institute, Department of Environmental Sciences, University of Basel, Basel CH-4051, Switzerland
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14
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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: 3] [Impact Index Per Article: 3.0] [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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15
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Beuder S, Braybrook SA. Brown algal cell walls and development. Semin Cell Dev Biol 2023; 134:103-111. [PMID: 35396168 DOI: 10.1016/j.semcdb.2022.03.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/17/2022] [Accepted: 03/04/2022] [Indexed: 10/18/2022]
Abstract
Brown algae are complex multicellular eukaryotes whose cells possess a cell wall, which is an important structure that regulates cell size and shape. Alginate and fucose-containing sulfated polysaccharides (FCSPs) are two carbohydrate types that have major roles in influencing the mechanical properties of the cell wall (i.e. increasing or decreasing wall stiffness), which in turn regulate cell expansion, division, adhesion, and other processes; however, how brown algal cell wall structure regulates its mechanical properties, and how this relationship influences cellular growth and organismal development, is not well-understood. This chapter is focused on reviewing what we currently know about how the roles of alginates and FCSPs in brown algal developmental processes, as well as how they influence the structural and mechanical properties of cell walls. Additionally, we discuss how brown algal mutants may be leveraged to learn more about the underlying mechanisms that regulate cell wall structure, mechanics, and developmental processes, and finally we propose questions to guide future research with the use of emerging technologies.
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Affiliation(s)
- Steven Beuder
- Department of Molecular, Cell, and Developmental Biology, UCLA, 610 Charles E Young Drive, Los Angeles, CA 90095, USA; California NanoSystems Institute, UCLA, 570 Westwood Plaza Building 114, Los Angeles, CA 90095, USA
| | - Siobhan A Braybrook
- Department of Molecular, Cell, and Developmental Biology, UCLA, 610 Charles E Young Drive, Los Angeles, CA 90095, USA; California NanoSystems Institute, UCLA, 570 Westwood Plaza Building 114, Los Angeles, CA 90095, USA; Molecular Biology Institute, UCLA, 611 Charles E. Young Drive, Los Angeles, CA 90095, USA.
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16
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Bogaert KA, Zakka EE, Coelho SM, De Clerck O. Polarization of brown algal zygotes. Semin Cell Dev Biol 2023; 134:90-102. [PMID: 35317961 DOI: 10.1016/j.semcdb.2022.03.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/01/2022] [Accepted: 03/03/2022] [Indexed: 11/29/2022]
Abstract
Brown algae are a group of multicellular, heterokont algae that have convergently evolved developmental complexity that rivals that of embryophytes, animals or fungi. Early in development, brown algal zygotes establish a basal and an apical pole, which will become respectively the basal system (holdfast) and the apical system (thallus) of the adult alga. Brown algae are interesting models for understanding the establishment of cell polarity in a broad evolutionary context, because they exhibit a large diversity of life cycles, reproductive strategies and, importantly, their zygotes are produced in large quantities free of parental tissue, with symmetry breaking and asymmetric division taking place in a highly synchronous manner. This review describes the current knowledge about the establishment of the apical-basal axis in the model brown seaweeds Ectocarpus, Dictyota, Fucus and Saccharina, highlighting the advantages and specific interests of each system. Ectocarpus is a genetic model system that allows access to the molecular basis of early development and life-cycle control over apical-basal polarity. The oogamous brown alga Fucus, together with emerging comparative models Dictyota and Saccharina, emphasize the diversity of strategies of symmetry breaking in determining a cell polarity vector in brown algae. A comparison with symmetry-breaking mechanisms in land plants, animals and fungi, reveals that the one-step zygote polarisation of Fucus compares well to Saccharomyces budding and Arabidopsis stomata development, while the two-phased symmetry breaking in the Dictyota zygote compares to Schizosaccharomyces fission, the Caenorhabditis anterior-posterior zygote polarisation and Arabidopsis prolate pollen polarisation. The apical-basal patterning in Saccharina zygotes on the other hand, may be seen as analogous to that of land plants. Overall, brown algae have the potential to bring exciting new information on how a single cell gives rise to an entire complex body plan.
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Affiliation(s)
- Kenny A Bogaert
- Phycology Research Group, Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium.
| | - Eliane E Zakka
- Phycology Research Group, Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium
| | - Susana M Coelho
- Department of Algal Development and Evolution, Max Planck Institute for Biology, Tübingen, Germany
| | - Olivier De Clerck
- Phycology Research Group, Department of Biology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent, Belgium
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17
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Casper AMA, Rebolledo N, Lane AK, Jude L, Eddy SL. "It's completely erasure": A Qualitative Exploration of Experiences of Transgender, Nonbinary, Gender Nonconforming, and Questioning Students in Biology Courses. CBE LIFE SCIENCES EDUCATION 2022; 21:ar69. [PMID: 36112619 PMCID: PMC9727607 DOI: 10.1187/cbe.21-12-0343] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Biology is the study of the diversity of life, which includes diversity in sex, gender, and sexual, romantic, and related orientations. However, a small body of literature suggests that undergraduate biology courses focus on only a narrow representation of this diversity (binary sexes, heterosexual orientations, etc.). In this study, we interviewed students with queer genders to understand the messages about sex, gender, and orientation they encountered in biology and the impact of these messages on them. We found five overarching themes in these interviews. Students described two narratives about sex, gender, and orientation in their biology classes that made biology implicitly exclusionary. These narratives harmed students by impacting their sense of belonging, career preparation, and interest in biology content. However, students employed a range of resilience strategies to resist these harms. Finally, students described the currently unrealized potential for biology and biology courses to validate queer identities by representing the diversity in sex and orientation in biology. We provide teaching suggestions derived from student interviews for making biology more queer-inclusive.
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Affiliation(s)
- A. M. Aramati Casper
- Department of Biology, Department of Civil and Environmental Engineering & Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523-1372
| | - Nico Rebolledo
- Department of Biological Sciences, Florida International University, Miami, FL 33199
| | - A. Kelly Lane
- Biology Teaching and Learning, Minneapolis, MN 55455
| | | | - Sarah L. Eddy
- Department of Biological Sciences, Florida International University, Miami, FL 33199
- *Address correspondence to: Sarah L. Eddy ()
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18
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Minelli A. Two-way exchanges between animal and plant biology, with focus on evo-devo. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.1057355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
By definition, biology is the science of all living beings. However, horizons restricted to either plants or animals have characterized the development of life sciences well beyond the emergence of unified perspectives applying to all forms of life, such as the cell theory or the theory of evolution. Separation between botanical and zoological traditions is not destined to go extinct easily, or shortly. Disciplinary isolation is emphasized by institutional contexts such as scientific societies and their congresses, specialist journals, disciplines recognized as teaching subjects and legitimate and fundable research fields. By shaping the personal agendas of individual scientists, this has a strong impact on the development of biology. In some fields, botanical and zoological contributions have long being effectively intertwined, but in many others plant and animal biology have failed to progress beyond a marginal dialogue. Characteristically, the so-called “general biology” and the philosophy of biology are still zoocentric (and often vertebrato- or even anthropocentric). In this article, I discuss legitimacy and fruitfulness of some old lexical and conceptual exchanges between the two traditions (cell, tissue, and embryo). Finally, moving to recent developments, I compare the contributions of plant vs. animal biology to the establishment of evolutionary developmental biology. We cannot expect that stronger integration between the different strands of life sciences will soon emerge by self-organization, but highlighting this persisting imbalance between plant and animal biology will arguably foster progress.
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Goecke F, Gómez Garreta A, Martín-Martín R, Rull Lluch J, Skjermo J, Ergon Å. Nuclear DNA Content Variation in Different Life Cycle Stages of Sugar Kelp, Saccharina latissima. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2022; 24:706-721. [PMID: 35882688 PMCID: PMC9385784 DOI: 10.1007/s10126-022-10137-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Ploidy variants can be utilized to increase yield, introduce sterility, and modify specific traits with an economic impact. Despite economic importance of Saccharina species, their nuclear DNA content in different cell types and life stages remain unclear. The present research was initiated to determine the nuclear DNA content and intraindividual variation at different life cycle stages of the Laminarialean kelp Saccharina latissima. Nuclear DNA content in embryonic and mature sporophytes, released and unreleased zoospores, female, and male gametophytes from Sør-Trøndelag county in Norway were estimated by image analysis using the DNA-localizing fluorochrome DAPI and chicken's red blood cells as a standard. DNA content of a total of 6905 DAPI-stained nuclei was estimated. This is the first study of nuclear DNA content which covered the life cycle of kelp. The lowest level of DNA content (1C) was observed in zoospores with an average of 0.76 pg. Male and female single spore gametophyte cultures presented higher average DNA content, more than double that of zoospores, suggesting the presence of polyteny. Female gametophyte nuclei were slightly larger and more variable in size than those of male gametophytes. The DNA content observed in embryonic sporophytes and in meristoderm cells from older sporophytes (1.51 pg) was 2C as expected and in the range of previously published studies of sporophytes of S. latissima. Mature sporophytes showed intra-plant variation with DNA content values ranging from 2-16C. The main difference was between meristoderm cells (mostly 2C) and cortical and medullary cells (2-16C).
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Affiliation(s)
- Franz Goecke
- Department of Plant Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway.
| | - Amelia Gómez Garreta
- Laboratori de Botànica, Facultat de Farmàcia I Ciències de L'Alimentació, Institut de Recerca de La Biodiversitat (IRBio) & Centre de Documentació de Biodiversitat Vegetal (CeDocBiV), Universitat de Barcelona, Barcelona, Spain
| | - Rafael Martín-Martín
- Laboratori de Botànica, Facultat de Farmàcia I Ciències de L'Alimentació, Institut de Recerca de La Biodiversitat (IRBio) & Centre de Documentació de Biodiversitat Vegetal (CeDocBiV), Universitat de Barcelona, Barcelona, Spain
| | - Jordi Rull Lluch
- Laboratori de Botànica, Facultat de Farmàcia I Ciències de L'Alimentació, Institut de Recerca de La Biodiversitat (IRBio) & Centre de Documentació de Biodiversitat Vegetal (CeDocBiV), Universitat de Barcelona, Barcelona, Spain
| | - Jorunn Skjermo
- Department of Fisheries and New Biomarine Industries, SINTEF Ocean, Trondheim, Norway
| | - Åshild Ergon
- Department of Plant Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
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20
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Cossard GG, Godfroy O, Nehr Z, Cruaud C, Cock JM, Lipinska AP, Coelho SM. Selection drives convergent gene expression changes during transitions to co-sexuality in haploid sexual systems. Nat Ecol Evol 2022; 6:579-589. [PMID: 35314785 PMCID: PMC9085613 DOI: 10.1038/s41559-022-01692-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 02/07/2022] [Indexed: 11/25/2022]
Abstract
Co-sexuality has evolved repeatedly from unisexual (dioicous) ancestors across a wide range of taxa. However, the molecular changes underpinning this important transition remain unknown, particularly in organisms with haploid sexual systems such as bryophytes, red algae and brown algae. Here we explore four independent events of emergence of co-sexuality from unisexual ancestors in brown algal clades to examine the nature, evolution and degree of convergence of gene expression changes that accompany the breakdown of dioicy. The amounts of male versus female phenotypic differences in dioicous species were not correlated with the extent of sex-biased gene expression, in stark contrast to what is observed in animals. Although sex-biased genes exhibited a high turnover rate during brown alga diversification, some of their predicted functions were conserved across species. Transitions to co-sexuality consistently involved adaptive gene expression shifts and rapid sequence evolution, particularly for male-biased genes. Gene expression in co-sexual species was more similar to that in females rather than males of related dioicous species, suggesting that co-sexuality may have arisen from ancestral females. Finally, extensive convergent gene expression changes, driven by selection, were associated with the transition to co-sexuality. Together, our observations provide insights on how co-sexual systems arise from ancestral, haploid UV sexual systems.
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Affiliation(s)
- Guillaume G Cossard
- Sorbonne Université, UPMC Univ Paris 06, CNRS, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS, Roscoff, France
- Max Plank Institute for Biology Tübingen, Tübingen, Germany
| | - Olivier Godfroy
- Sorbonne Université, UPMC Univ Paris 06, CNRS, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS, Roscoff, France
| | - Zofia Nehr
- Sorbonne Université, UPMC Univ Paris 06, CNRS, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS, Roscoff, France
| | - Corinne Cruaud
- Genoscope, Institut de Biologie François Jacob, CEA, Université Paris-Saclay, Evry, France
| | - J Mark Cock
- Sorbonne Université, UPMC Univ Paris 06, CNRS, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS, Roscoff, France
| | - Agnieszka P Lipinska
- Sorbonne Université, UPMC Univ Paris 06, CNRS, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS, Roscoff, France
- Max Plank Institute for Biology Tübingen, Tübingen, Germany
| | - Susana M Coelho
- Sorbonne Université, UPMC Univ Paris 06, CNRS, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS, Roscoff, France.
- Max Plank Institute for Biology Tübingen, Tübingen, Germany.
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21
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Constable GWA, Kokko H. Parthenogenesis and the Evolution of Anisogamy. Cells 2021; 10:2467. [PMID: 34572116 PMCID: PMC8467976 DOI: 10.3390/cells10092467] [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: 05/25/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 01/10/2023] Open
Abstract
Recently, it was pointed out that classic models for the evolution of anisogamy do not take into account the possibility of parthenogenetic reproduction, even though sex is facultative in many relevant taxa (e.g., algae) that harbour both anisogamous and isogamous species. Here, we complement this recent analysis with an approach where we assume that the relationship between progeny size and its survival may differ between parthenogenetically and sexually produced progeny, favouring either the former or the latter. We show that previous findings that parthenogenesis can stabilise isogamy relative to the obligate sex case, extend to our scenarios. We additionally investigate two different ways for one mating type to take over the entire population. First, parthenogenesis can lead to biased sex ratios that are sufficiently extreme that one type can displace the other, leading to de facto asexuality for the remaining type that now lacks partners to fuse with. This process involves positive feedback: microgametes, being numerous, lack opportunities for syngamy, and should they proliferate parthenogenetically, the next generation makes this asexual route even more prominent for microgametes. Second, we consider mutations to strict asexuality in producers of micro- or macrogametes, and show that the prospects of asexual invasion depend strongly on the mating type in which the mutation arises. Perhaps most interestingly, we also find scenarios in which parthenogens have an intrinsic survival advantage yet facultatively sexual isogamous populations are robust to the invasion of asexuals, despite us assuming no genetic benefits of recombination. Here, equal contribution from both mating types to zygotes that are sufficiently well provisioned can outweigh the additional costs associated with syngamy.
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Affiliation(s)
| | - Hanna Kokko
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, CH-8057 Zurich, Switzerland
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