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Hörandl E. Apomixis and the paradox of sex in plants. ANNALS OF BOTANY 2024; 134:1-18. [PMID: 38497809 PMCID: PMC11161571 DOI: 10.1093/aob/mcae044] [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: 12/11/2023] [Accepted: 03/15/2024] [Indexed: 03/19/2024]
Abstract
BACKGROUND The predominance of sex in eukaryotes, despite the high costs of meiosis and mating, remains an evolutionary enigma. Many theories have been proposed, none of them being conclusive on its own, and they are, in part, not well applicable to land plants. Sexual reproduction is obligate in embryophytes for the great majority of species. SCOPE This review compares the main forms of sexual and asexual reproduction in ferns and angiosperms, based on the generation cycling of sporophyte and gametophyte (leaving vegetative propagation aside). The benefits of sexual reproduction for maintenance of genomic integrity in comparison to asexuality are discussed in the light of developmental, evolutionary, genetic and phylogenetic studies. CONCLUSIONS Asexual reproduction represents modifications of the sexual pathway, with various forms of facultative sexuality. For sexual land plants, meiosis provides direct DNA repair mechanisms for oxidative damage in reproductive tissues. The ploidy alternations of meiosis-syngamy cycles and prolonged multicellular stages in the haploid phase in the gametophytes provide a high efficiency of purifying selection against recessive deleterious mutations. Asexual lineages might buffer effects of such mutations via polyploidy and can purge the mutational load via facultative sexuality. The role of organelle-nuclear genome compatibility for maintenance of genome integrity is not well understood. In plants in general, the costs of mating are low because of predominant hermaphroditism. Phylogenetic patterns in the archaeplastid clade suggest that high frequencies of sexuality in land plants are concomitant with a stepwise increase of intrinsic and extrinsic stress factors. Furthermore, expansion of genome size in land plants would increase the potential mutational load. Sexual reproduction appears to be essential for keeping long-term genomic integrity, and only rare combinations of extrinsic and intrinsic factors allow for shifts to asexuality.
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Affiliation(s)
- Elvira Hörandl
- Department of Systematics, Biodiversity and Evolution of Plants (with herbarium), University of Göttingen, Göttingen, Germany
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2
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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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Kimball A, Funkhouser-Jones L, Huang W, Xu R, Witola WH, Sibley LD. Mendelian segregation and high recombination rates facilitate genetic analyses in Cryptosporidium parvum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.02.578536. [PMID: 38352509 PMCID: PMC10862819 DOI: 10.1101/2024.02.02.578536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Very little is known about the process of meiosis in the apicomplexan parasite Cryptosporidium despite the essentiality of sex in its life cycle. Most cell lines only support asexual growth of Cryptosporidium parvum (C. parvum), but stem cell derived intestinal epithelial cells grown under air-liquid interface (ALI) conditions support the sexual cycle. To examine chromosomal dynamics during meiosis in C. parvum, we generated two transgenic lines of parasites that were fluorescently tagged with mCherry or GFP on chromosomes 1 or 5, respectively. Infection of ALI cultures or Ifngr1-/- mice with mCherry and GFP parasites produced "yellow" oocysts generated by cross-fertilization. Outcrossed oocysts from the F1 generation were purified and used to infect HCT-8 cultures, and phenotypes of the progeny were observed by microscopy. All possible phenotypes predicted by independent segregation were represented equally (~25%) in the population, indicating that C. parvum chromosomes exhibit a Mendelian inheritance pattern. Unexpectedly, the most common pattern observed from the outgrowth of single oocysts included all possible parental and recombinant phenotypes derived from a single meiotic event, suggesting a high rate of crossover. To estimate the frequency of crossover, additional loci on chromosomes 1 and 5 were tagged and used to monitor intrachromosomal crosses in Ifngr1-/- mice. Both chromosomes showed a high frequency of crossover compared to other apicomplexans with map distances (i.e., 1% recombination) of 3-12 kb. Overall, a high recombination rate may explain many unique characteristics observed in Cryptosporidium spp. such as high rates of speciation, wide variation in host range, and rapid evolution of host-specific virulence factors.
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Affiliation(s)
- Abigail Kimball
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Lisa Funkhouser-Jones
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Wanyi Huang
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Rui Xu
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - William H. Witola
- Department of Pathobiology, University of Illinois Urbana-Champaign College of Veterinary Medicine, Urbana, IL 61802, USA
| | - L. David Sibley
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Steins L, Guerreiro MA, Duhamel M, Liu F, Wang QM, Boekhout T, Begerow D. Comparative genomics of smut fungi suggest the ability of meiosis and mating in asexual species of the genus Pseudozyma (Ustilaginales). BMC Genomics 2023; 24:321. [PMID: 37312063 DOI: 10.1186/s12864-023-09387-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 05/18/2023] [Indexed: 06/15/2023] Open
Abstract
BACKGROUND The Ustilaginales comprise hundreds of plant-parasitic fungi with a characteristic life cycle that directly links sexual reproduction and parasitism: One of the two mating-type loci codes for a transcription factor that not only facilitates mating, but also initiates the infection process. However, several species within the Ustilaginales have no described parasitic stage and were historically assigned to the genus Pseudozyma. Molecular studies have shown that the group is polyphyletic, with members being scattered in various lineages of the Ustilaginales. Together with recent findings of conserved fungal effectors in these non-parasitic species, this raises the question if parasitism has been lost recently and in multiple independent events or if there are hitherto undescribed parasitic stages of these fungi. RESULTS In this study, we sequenced genomes of five Pseudozyma species together with six parasitic species from the Ustilaginales to compare their genomic capability to perform two central functions in sexual reproduction: mating and meiosis. While the loss of sexual capability is assumed in certain lineages and asexual species are common in Asco- and Basidiomycota, we were able to successfully annotate potentially functional mating and meiosis genes that are conserved throughout the whole group. CONCLUSION Our data suggest that at least the key functions of a sexual lifestyle are maintained in the analyzed genomes, challenging the current understanding of the so-called asexual species with respect to their evolution and ecological role.
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Affiliation(s)
- Lena Steins
- Evolution of Plants and Fungi, Ruhr-University Bochum, Bochum, Germany
| | - Marco Alexandre Guerreiro
- Evolution of Plants and Fungi, Ruhr-University Bochum, Bochum, Germany
- Environmental Genomics, Germany and Max Planck Institute for Evolutionary Biology, Botanical Institute, Christian-Albrechts University of Kiel, Plön, Germany
| | - Marine Duhamel
- Evolution of Plants and Fungi, Ruhr-University Bochum, Bochum, Germany
- Ecologie Systématique Evolution, IDEEV, CNRS, Université Paris-Saclay, AgroParisTech, Gif-Sur-Yvette, Paris, France
| | - Fei Liu
- School of Life Sciences, Institute of Life Sciences and Green Development, Hebei University, Baoding, 071002, Hebei, China
| | - Qi-Ming Wang
- School of Life Sciences, Institute of Life Sciences and Green Development, Hebei University, Baoding, 071002, Hebei, China
| | - Teun Boekhout
- College of Science, King Saud University, Riyadh, Saudi Arabia
- Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands
| | - Dominik Begerow
- Evolution of Plants and Fungi, Ruhr-University Bochum, Bochum, Germany.
- Organismic Botany and Mycology, University of Hamburg, IPM, Hamburg, Germany.
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5
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da Silva VS, Machado CR. Sex in protists: A new perspective on the reproduction mechanisms of trypanosomatids. Genet Mol Biol 2022; 45:e20220065. [PMID: 36218381 PMCID: PMC9552303 DOI: 10.1590/1678-4685-gmb-2022-0065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 08/07/2022] [Indexed: 11/04/2022] Open
Abstract
The Protist kingdom individuals are the most ancestral representatives of
eukaryotes. They have inhabited Earth since ancient times and are currently
found in the most diverse environments presenting a great heterogeneity of life
forms. The unicellular and multicellular algae, photosynthetic and heterotrophic
organisms, as well as free-living and pathogenic protozoa represents the protist
group. The evolution of sex is directly associated with the origin of eukaryotes
being protists the earliest protagonists of sexual reproduction on earth. In
eukaryotes, the recombination through genetic exchange is a ubiquitous mechanism
that can be stimulated by DNA damage. Scientific evidences support the
hypothesis that reactive oxygen species (ROS) induced DNA damage can promote
sexual recombination in eukaryotes which might have been a decisive factor for
the origin of sex. The fact that some recombination enzymes also participate in
meiotic sex in modern eukaryotes reinforces the idea that sexual reproduction
emerged as consequence of specific mechanisms to cope with mutations and
alterations in genetic material. In this review we will discuss about origin of
sex and different strategies of evolve sexual reproduction in some protists such
that cause human diseases like malaria, toxoplasmosis, sleeping sickness, Chagas
disease, and leishmaniasis.
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Affiliation(s)
- Verônica Santana da Silva
- Universidade Federal de Minas Gerais, Departamento de Genética,
Ecologia e Evolução, Belo Horizonte, MG, Brazil
| | - Carlos Renato Machado
- Universidade Federal de Minas Gerais, Departamento de Bioquímica e
Imunologia, Belo Horizonte, MG, Brazil
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6
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Lara E, Singer D, Geisen S. Discrepancies between prokaryotes and eukaryotes need to be considered in soil DNA-based studies. Environ Microbiol 2022; 24:3829-3839. [PMID: 35437903 PMCID: PMC9790305 DOI: 10.1111/1462-2920.16019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/12/2022] [Accepted: 04/14/2022] [Indexed: 12/30/2022]
Abstract
Metabarcoding approaches are exponentially increasing our understanding of soil biodiversity, with a major focus on the bacterial part of the microbiome. Part of the soil diversity are also eukaryotes that include fungi, algae, protists and Metazoa. Nowadays, soil eukaryotes are targeted with the same approaches developed for bacteria and archaea (prokaryotes). However, fundamental differences exist between domains. After providing a short historical overview of the developments of metabarcoding applied to environmental microbiology, we compile the most important differences between domains that prevent direct method transfers between prokaryotic and eukaryotic soil metabarcoding approaches, currently dominated by short-read sequencing. These include the existence of divergent diversity concepts and the variations in eukaryotic morphology that affect sampling and DNA extraction. Furthermore, eukaryotes experienced much more variable evolutionary rates than prokaryotes, which prevent capturing the entire eukaryotic diversity in a soil with a single amplification protocol fit for short-read sequencing. In the final part we focus on future potentials for optimization of eukaryotic metabarcoding that include superior possibility of functionally characterizing eukaryotes and to extend the current information obtained, such as by adding a real quantitative component. This review should optimize future metabarcoding approaches targeting soil eukaryotes and kickstart this promising research direction.
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Affiliation(s)
- Enrique Lara
- Real Jardín Botánico‐CSIC, Plaza de Murillo 2Madrid28014Spain
| | - David Singer
- UMR CNRS 6112 LPG‐BIAFAngers University, 2 Boulevard LavoisierAngers49045France
| | - Stefan Geisen
- Laboratory of NematologyWageningen UniversityWageningen6700 AAThe Netherlands
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7
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Li XY, Mei J, Ge CT, Liu XL, Gui JF. Sex determination mechanisms and sex control approaches in aquaculture animals. SCIENCE CHINA. LIFE SCIENCES 2022; 65:1091-1122. [PMID: 35583710 DOI: 10.1007/s11427-021-2075-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 01/14/2022] [Indexed: 01/21/2023]
Abstract
Aquaculture is one of the most efficient modes of animal protein production and plays an important role in global food security. Aquaculture animals exhibit extraordinarily diverse sexual phenotypes and underlying mechanisms, providing an ideal system to perform sex determination research, one of the important areas in life science. Moreover, sex is also one of the most valuable traits because sexual dimorphism in growth, size, and other economic characteristics commonly exist in aquaculture animals. Here, we synthesize current knowledge of sex determination mechanisms, sex chromosome evolution, reproduction strategies, and sexual dimorphism, and also review several approaches for sex control in aquaculture animals, including artificial gynogenesis, application of sex-specific or sex chromosome-linked markers, artificial sex reversal, as well as gene editing. We anticipate that better understanding of sex determination mechanisms and innovation of sex control approaches will facilitate sustainable development of aquaculture.
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Affiliation(s)
- Xi-Yin Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, The Innovative Academy of Seed Design, Institute of Hydrobiology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Wuhan, 430072, China
| | - Jie Mei
- College of Fisheries, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Chu-Tian Ge
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, China
| | - Xiao-Li Liu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation of Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510380, China
| | - Jian-Fang Gui
- State Key Laboratory of Freshwater Ecology and Biotechnology, Hubei Hongshan Laboratory, The Innovative Academy of Seed Design, Institute of Hydrobiology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Wuhan, 430072, China.
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8
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Foe VE. Does the Pachytene Checkpoint, a Feature of Meiosis, Filter Out Mistakes in Double-Strand DNA Break Repair and as a side-Effect Strongly Promote Adaptive Speciation? Integr Org Biol 2022; 4:obac008. [PMID: 36827645 PMCID: PMC8998493 DOI: 10.1093/iob/obac008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
This essay aims to explain two biological puzzles: why eukaryotic transcription units are composed of short segments of coding DNA interspersed with long stretches of non-coding (intron) DNA, and the near ubiquity of sexual reproduction. As is well known, alternative splicing of its coding sequences enables one transcription unit to produce multiple variants of each encoded protein. Additionally, padding transcription units with non-coding DNA (often many thousands of base pairs long) provides a readily evolvable way to set how soon in a cell cycle the various mRNAs will begin being expressed and the total amount of mRNA that each transcription unit can make during a cell cycle. This regulation complements control via the transcriptional promoter and facilitates the creation of complex eukaryotic cell types, tissues, and organisms. However, it also makes eukaryotes exceedingly vulnerable to double-strand DNA breaks, which end-joining break repair pathways can repair incorrectly. Transcription units cover such a large fraction of the genome that any mis-repair producing a reorganized chromosome has a high probability of destroying a gene. During meiosis, the synaptonemal complex aligns homologous chromosome pairs and the pachytene checkpoint detects, selectively arrests, and in many organisms actively destroys gamete-producing cells with chromosomes that cannot adequately synapse; this creates a filter favoring transmission to the next generation of chromosomes that retain the parental organization, while selectively culling those with interrupted transcription units. This same meiotic checkpoint, reacting to accidental chromosomal reorganizations inflicted by error-prone break repair, can, as a side effect, provide a mechanism for the formation of new species in sympatry. It has been a long-standing puzzle how something as seemingly maladaptive as hybrid sterility between such new species can arise. I suggest that this paradox is resolved by understanding the adaptive importance of the pachytene checkpoint, as outlined above.
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9
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Pinello JF, Clark TG. HAP2-Mediated Gamete Fusion: Lessons From the World of Unicellular Eukaryotes. Front Cell Dev Biol 2022; 9:807313. [PMID: 35071241 PMCID: PMC8777248 DOI: 10.3389/fcell.2021.807313] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 11/15/2021] [Indexed: 01/29/2023] Open
Abstract
Most, if not all the cellular requirements for fertilization and sexual reproduction arose early in evolution and are retained in extant lineages of single-celled organisms including a number of important model organism species. In recent years, work in two such species, the green alga, Chlamydomonas reinhardtii, and the free-living ciliate, Tetrahymena thermophila, have lent important new insights into the role of HAP2/GCS1 as a catalyst for gamete fusion in organisms ranging from protists to flowering plants and insects. Here we summarize the current state of knowledge around how mating types from these algal and ciliate systems recognize, adhere and fuse to one another, current gaps in our understanding of HAP2-mediated gamete fusion, and opportunities for applying what we know in practical terms, especially for the control of protozoan parasites.
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Affiliation(s)
- Jennifer F. Pinello
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, United States
| | - Theodore G. Clark
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, United States
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10
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Skejo J, Garg SG, Gould SB, Hendriksen M, Tria FDK, Bremer N, Franjević D, Blackstone NW, Martin WF. Evidence for a Syncytial Origin of Eukaryotes from Ancestral State Reconstruction. Genome Biol Evol 2021; 13:evab096. [PMID: 33963405 PMCID: PMC8290118 DOI: 10.1093/gbe/evab096] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/2021] [Indexed: 12/11/2022] Open
Abstract
Modern accounts of eukaryogenesis entail an endosymbiotic encounter between an archaeal host and a proteobacterial endosymbiont, with subsequent evolution giving rise to a unicell possessing a single nucleus and mitochondria. The mononucleate state of the last eukaryotic common ancestor (LECA) is seldom, if ever, questioned, even though cells harboring multiple (syncytia, coenocytes, and polykaryons) are surprisingly common across eukaryotic supergroups. Here, we present a survey of multinucleated forms. Ancestral character state reconstruction for representatives of 106 eukaryotic taxa using 16 different possible roots and supergroup sister relationships, indicate that LECA, in addition to being mitochondriate, sexual, and meiotic, was multinucleate. LECA exhibited closed mitosis, which is the rule for modern syncytial forms, shedding light on the mechanics of its chromosome segregation. A simple mathematical model shows that within LECA's multinucleate cytosol, relationships among mitochondria and nuclei were neither one-to-one, nor one-to-many, but many-to-many, placing mitonuclear interactions and cytonuclear compatibility at the evolutionary base of eukaryotic cell origin. Within a syncytium, individual nuclei and individual mitochondria function as the initial lower-level evolutionary units of selection, as opposed to individual cells, during eukaryogenesis. Nuclei within a syncytium rescue each other's lethal mutations, thereby postponing selection for viable nuclei and cytonuclear compatibility to the generation of spores, buffering transitional bottlenecks at eukaryogenesis. The prokaryote-to-eukaryote transition is traditionally thought to have left no intermediates, yet if eukaryogenesis proceeded via a syncytial common ancestor, intermediate forms have persisted to the present throughout the eukaryotic tree as syncytia but have so far gone unrecognized.
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Affiliation(s)
- Josip Skejo
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- Faculty of Science, Division of Zoology, Department of Biology, University of Zagreb, Evolution Lab, Zagreb, Croatia
| | - Sriram G Garg
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Sven B Gould
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Michael Hendriksen
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Fernando D K Tria
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Nico Bremer
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Damjan Franjević
- Faculty of Science, Division of Zoology, Department of Biology, University of Zagreb, Evolution Lab, Zagreb, Croatia
| | - Neil W Blackstone
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL, USA
| | - William F Martin
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
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11
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Peixoto JF, dos Santos DG, Ribeiro L, de Oliveira VSC, Nunes-da-Fonseca R, Nepomuceno-Silva JL. Establishment of suitable reference genes for studying relative gene expression during the transition from trophozoites to cyst-like stages and first evidences of stress-induced expression of meiotic genes in Trichomonas vaginalis. Parasitology 2021; 148:934-946. [PMID: 33827719 PMCID: PMC11010144 DOI: 10.1017/s0031182021000585] [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: 11/01/2020] [Revised: 03/26/2021] [Accepted: 03/29/2021] [Indexed: 11/07/2022]
Abstract
Trichomonas vaginalis is a parasite of the human urogenital tract and the causative agent of trichomoniasis, a sexually transmitted disease of worldwide importance. This parasite is usually found as a motile flagellated trophozoite. However, when subjected to stressful microenvironmental conditions, T. vaginalis trophozoites can differentiate into peculiar cyst-like stages, which exhibit notable physiological resistance to unfavourable conditions. Although well documented in morphological and proteomic terms, patterns of gene expression changes involved in the cellular differentiation into cyst-like stages are mostly unknown. The real-time reverse transcription polymerase chain reaction (RT-qPCR) is recognized as a sensitive and accurate method for quantification of gene expression, providing fluorescence-based data that are proportional to the amount of a target RNA. However, the reliability of relative expression studies depends on the validation of suitable reference genes, which RNAs exhibit a minimum of variation between tested conditions. Here, we attempt to determine suitable reference genes to be used as controls of invariant expression during cold-induced in vitro differentiation of T. vaginalis trophozoites into cyst-like forms. Furthermore, we reveal that the mRNA from the meiotic recombinase Dmc1 is upregulated during this process, indicating that cryptic sexual events may take place in cyst-like stages of T. vaginalis.
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Affiliation(s)
- Juliana Figueiredo Peixoto
- Laboratório Integrado de Bioquímica Hatisaburo Masuda (LIBHM), Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Universidade Federal do Rio de Janeiro, Macaé/RJ, Brazil
| | - Daniele Graças dos Santos
- Laboratório Integrado de Bioquímica Hatisaburo Masuda (LIBHM), Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Universidade Federal do Rio de Janeiro, Macaé/RJ, Brazil
| | - Lupis Ribeiro
- Laboratório Integrado de Ciências Morfofuncionais (LICM), Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Universidade Federal do Rio de Janeiro, Macaé/RJ, Brazil
| | - Vitor Silva Cândido de Oliveira
- Laboratório Integrado de Bioquímica Hatisaburo Masuda (LIBHM), Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Universidade Federal do Rio de Janeiro, Macaé/RJ, Brazil
| | - Rodrigo Nunes-da-Fonseca
- Laboratório Integrado de Ciências Morfofuncionais (LICM), Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Universidade Federal do Rio de Janeiro, Macaé/RJ, Brazil
| | - José Luciano Nepomuceno-Silva
- Laboratório Integrado de Bioquímica Hatisaburo Masuda (LIBHM), Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Universidade Federal do Rio de Janeiro, Macaé/RJ, Brazil
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12
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A functional bacteria-derived restriction modification system in the mitochondrion of a heterotrophic protist. PLoS Biol 2021; 19:e3001126. [PMID: 33891594 PMCID: PMC8099122 DOI: 10.1371/journal.pbio.3001126] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 05/05/2021] [Accepted: 03/23/2021] [Indexed: 01/04/2023] Open
Abstract
The overarching trend in mitochondrial genome evolution is functional streamlining coupled with gene loss. Therefore, gene acquisition by mitochondria is considered to be exceedingly rare. Selfish elements in the form of self-splicing introns occur in many organellar genomes, but the wider diversity of selfish elements, and how they persist in the DNA of organelles, has not been explored. In the mitochondrial genome of a marine heterotrophic katablepharid protist, we identify a functional type II restriction modification (RM) system originating from a horizontal gene transfer (HGT) event involving bacteria related to flavobacteria. This RM system consists of an HpaII-like endonuclease and a cognate cytosine methyltransferase (CM). We demonstrate that these proteins are functional by heterologous expression in both bacterial and eukaryotic cells. These results suggest that a mitochondrion-encoded RM system can function as a toxin-antitoxin selfish element, and that such elements could be co-opted by eukaryotic genomes to drive biased organellar inheritance.
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13
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Maroc L, Fairhead C. Lessons from the Nakaseomyces: mating-type switching, DSB repair and evolution of Ho. Curr Genet 2021; 67:685-693. [PMID: 33830322 DOI: 10.1007/s00294-021-01182-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/22/2021] [Accepted: 03/24/2021] [Indexed: 12/19/2022]
Abstract
This short paper aims to review what our recent studies in the Nakaseomyces yeasts, principally Candida glabrata, reveal about the evolution of the mating-type switching system and its components, as well as about the repair of chromosomal double-strand breaks in this clade. In the model yeast Saccharomyces cerevisiae, the study of mating-type switching has, over the years, led to major discoveries in how cells process chromosomal breaks. Indeed, in this species, switching, which allows every haploid cell to produce cells of opposite mating types that can mate together, is initiated by the Ho endonuclease, linking sexual reproduction to a programmed chromosomal cut. More recently, the availability of other yeasts' genomes from type strains and from populations, and the ability to manipulate and edit the genomes of most yeasts in the laboratory, has enabled scientists to explore mating-type switching in new species, thus enriching our evolutionary perspective on this phenomenon. In this review, we will show how the study of mating-type switching in C. glabrata and Nakaseomyces delphensis has allowed us to reveal possible additional roles for Ho, and also to discover major differences in DSB repair at central and subtelomeric sexual loci. In addition, we report how the study of repair of chromosomal breaks induced by CRISPR-Cas9 reveals that efficient and faithful NHEJ is a major repair pathway in C. glabrata.
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Affiliation(s)
- Laetitia Maroc
- GQE-Le Moulon, Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Ferme du Moulon, 91190, Gif-sur-Yvette, France
| | - Cécile Fairhead
- GQE-Le Moulon, Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Ferme du Moulon, 91190, Gif-sur-Yvette, France.
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Berdieva MA, Pozdnyakov IA, Kalinina VO, Skarlato SO. Putative Meiotic Toolkit in the Dinoflagellate Prorocentrum cordatum: Additional Evidence for Sexual Process from Transcriptome. J Eukaryot Microbiol 2021; 68:e12845. [PMID: 33624379 DOI: 10.1111/jeu.12845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 01/25/2021] [Accepted: 02/13/2021] [Indexed: 01/16/2023]
Abstract
Prorocentrum cordatum (Ostenfeld) Dodge-is a planktonic armored dinoflagellate that is a bloom-forming, potentially toxic cosmopolitan species. The transition from vegetative reproduction to the sexual process has been recently shown for this organism. Here, we present the results of transcriptomic data analysis that uncovered one syngamy-associated and 16 meiosis-associated proteins in P. cordatum. We also detected an amino acid sequence homologous to bacterial MutS2 protein. The MutS2 presence and origin in dinoflagellates are discussed for the first time.
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Affiliation(s)
- Mariia A Berdieva
- Institute of Cytology of the Russian Academy of Science, Tikhoretsky Avenue 4, St. Petersburg, 194064, Russia
| | - Ilya A Pozdnyakov
- Institute of Cytology of the Russian Academy of Science, Tikhoretsky Avenue 4, St. Petersburg, 194064, Russia
| | - Vera O Kalinina
- Institute of Cytology of the Russian Academy of Science, Tikhoretsky Avenue 4, St. Petersburg, 194064, Russia
| | - Sergei O Skarlato
- Institute of Cytology of the Russian Academy of Science, Tikhoretsky Avenue 4, St. Petersburg, 194064, Russia
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15
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Öztoprak H, Walden S, Heger T, Bonkowski M, Dumack K. What Drives the Diversity of the Most Abundant Terrestrial Cercozoan Family (Rhogostomidae, Cercozoa, Rhizaria)? Microorganisms 2020; 8:E1123. [PMID: 32722603 PMCID: PMC7463998 DOI: 10.3390/microorganisms8081123] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/22/2020] [Accepted: 07/23/2020] [Indexed: 12/25/2022] Open
Abstract
Environmental sequencing surveys of soils and freshwaters revealed high abundance and diversity of the Rhogostomidae, a group of omnivorous thecate amoebae. This is puzzling since only a few Rhogostomidae species have yet been described and only a handful of reports mention them in field surveys. We investigated the putative cryptic diversity of the Rhogostomidae by a critical re-evaluation of published environmental sequencing data and in-depth ecological and morphological trait analyses. The Rhogostomidae exhibit an amazing diversity of genetically distinct clades that occur in a variety of different environments. We further broadly sampled for Rhogostomidae species; based on these isolates, we describe eleven new species and highlight important morphological traits for species delimitation. The most important environmental drivers that shape the Rhogostomidae community were soil moisture, soil pH, and total plant biomass. The length/width ratio of the theca was a morphological trait related to the colonized habitats, but not the shape and size of the aperture that is often linked to moisture adaption in testate and thecate amoebae.
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Affiliation(s)
- Hüsna Öztoprak
- Institute of Zoology, Terrestrial Ecology, University of Cologne, Zülpicher Str. 47b, 50674 Köln, Germany; (H.Ö.); (S.W.); (M.B.)
| | - Susanne Walden
- Institute of Zoology, Terrestrial Ecology, University of Cologne, Zülpicher Str. 47b, 50674 Köln, Germany; (H.Ö.); (S.W.); (M.B.)
| | - Thierry Heger
- Soil Science and Environment Group, CHANGINS, University of Applied Sciences and Arts Western Switzerland, Route de Duillier 50, 1260 Nyon, Switzerland;
| | - Michael Bonkowski
- Institute of Zoology, Terrestrial Ecology, University of Cologne, Zülpicher Str. 47b, 50674 Köln, Germany; (H.Ö.); (S.W.); (M.B.)
| | - Kenneth Dumack
- Institute of Zoology, Terrestrial Ecology, University of Cologne, Zülpicher Str. 47b, 50674 Köln, Germany; (H.Ö.); (S.W.); (M.B.)
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16
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Lara E, Dumack K, García-Martín JM, Kudryavtsev A, Kosakyan A. Amoeboid protist systematics: A report on the "Systematics of amoeboid protists" symposium at the VIIIth ECOP/ISOP meeting in Rome, 2019. Eur J Protistol 2020; 76:125727. [PMID: 32755801 DOI: 10.1016/j.ejop.2020.125727] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 05/22/2020] [Accepted: 06/25/2020] [Indexed: 01/21/2023]
Abstract
Amoeboid protists are extremely abundant and diverse in natural systems where they often play outstanding ecological roles. They can be found in almost all major eukaryotic divisions, and genomic approaches are bringing major changes in our perception of their deep evolutionary relationships. At fine taxonomic levels, the generalization of barcoding is revealing a considerable and unsuspected specific diversity that can be appreciated with careful morphometric analyses based on light and electron microscopic observations. We provide examples on the difficulties and advances in amoeboid protists systematics in a selection of groups that were presented at the VIIIth ECOP/ISOP meeting in Rome, 2019. We conclude that, in all studied groups, important taxonomical rearrangements will certainly take place in the next few years, and systematics must be adapted to incorporate these changes. Notably, nomenclature should be flexible enough to integrate many new high level taxa, and a unified policy must be adopted to species description and to the establishment of types.
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Affiliation(s)
- Enrique Lara
- Real Jardín Botánico de Madrid, CSIC, Plaza de Murillo 2, 28014 Madrid, Spain.
| | - Kenneth Dumack
- Terrestrial Ecology, Institute of Zoology, University of Cologne, Zülpicher Str. 47b, 50674 Köln, Germany
| | | | - Alexander Kudryavtsev
- Laboratory of Cellular and Molecular Protistology, Zoological Institute of the Russian Academy of Sciences, Universitetskaya nab. 1, 199034 Saint-Petersburg, Russia; Department of Invertebrate Zoology, Faculty of Biology, Saint-Petersburg State University, Universitetskaya nab. 7/9, 199034 Saint-Petersburg, Russia
| | - Anush Kosakyan
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic
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Hofstatter PG, Ribeiro GM, Porfírio‐Sousa AL, Lahr DJG. The Sexual Ancestor of all Eukaryotes: A Defense of the “Meiosis Toolkit”. Bioessays 2020; 42:e2000037. [DOI: 10.1002/bies.202000037] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 05/08/2020] [Indexed: 12/16/2022]
Affiliation(s)
- Paulo G. Hofstatter
- Universidade de São Paulo Instituto de Biociencias, Rua do Matão, travessa 14, A101. São Paulo, CEP.: 05508‐090, Brazil
| | - Giulia M. Ribeiro
- Universidade de São Paulo Instituto de Biociencias, Rua do Matão, travessa 14, A101. São Paulo, CEP.: 05508‐090, Brazil
| | - Alfredo L. Porfírio‐Sousa
- Universidade de São Paulo Instituto de Biociencias, Rua do Matão, travessa 14, A101. São Paulo, CEP.: 05508‐090, Brazil
| | - Daniel J. G. Lahr
- Universidade de São Paulo Instituto de Biociencias, Rua do Matão, travessa 14, A101. São Paulo, CEP.: 05508‐090, Brazil
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Sex in Symbiodiniaceae dinoflagellates: genomic evidence for independent loss of the canonical synaptonemal complex. Sci Rep 2020; 10:9792. [PMID: 32555361 PMCID: PMC7299967 DOI: 10.1038/s41598-020-66429-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 05/19/2020] [Indexed: 01/07/2023] Open
Abstract
Dinoflagellates of the Symbiodiniaceae family encompass diverse symbionts that are critical to corals and other species living in coral reefs. It is well known that sexual reproduction enhances adaptive evolution in changing environments. Although genes related to meiotic functions were reported in Symbiodiniaceae, cytological evidence of meiosis and fertilisation are however yet to be observed in these taxa. Using transcriptome and genome data from 21 Symbiodiniaceae isolates, we studied genes that encode proteins associated with distinct stages of meiosis and syngamy. We report the absence of genes that encode main components of the synaptonemal complex (SC), a protein structure that mediates homologous chromosomal pairing and class I crossovers. This result suggests an independent loss of canonical SCs in the alveolates, that also includes the SC-lacking ciliates. We hypothesise that this loss was due in part to permanently condensed chromosomes and repeat-rich sequences in Symbiodiniaceae (and other dinoflagellates) which favoured the SC-independent class II crossover pathway. Our results reveal novel insights into evolution of the meiotic molecular machinery in the ecologically important Symbiodiniaceae and in other eukaryotes.
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Zybina TG, Zybina EV. Role of cell cycling and polyploidy in placental trophoblast of different mammalian species. Reprod Domest Anim 2020; 55:895-904. [DOI: 10.1111/rda.13732] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 05/07/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Tatiana G. Zybina
- Laboratory of Cell Morphology Institute of Cytology RAS St.‐Petersburg Russia
| | - Eugenia V. Zybina
- Laboratory of Cell Morphology Institute of Cytology RAS St.‐Petersburg Russia
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"Mitotic Slippage" and Extranuclear DNA in Cancer Chemoresistance: A Focus on Telomeres. Int J Mol Sci 2020; 21:ijms21082779. [PMID: 32316332 PMCID: PMC7215480 DOI: 10.3390/ijms21082779] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/13/2020] [Accepted: 04/14/2020] [Indexed: 02/07/2023] Open
Abstract
Mitotic slippage (MS), the incomplete mitosis that results in a doubled genome in interphase, is a typical response of TP53-mutant tumors resistant to genotoxic therapy. These polyploidized cells display premature senescence and sort the damaged DNA into the cytoplasm. In this study, we explored MS in the MDA-MB-231 cell line treated with doxorubicin (DOX). We found selective release into the cytoplasm of telomere fragments enriched in telomerase reverse transcriptase (hTERT), telomere capping protein TRF2, and DNA double-strand breaks marked by γH2AX, in association with ubiquitin-binding protein SQSTM1/p62. This occurs along with the alternative lengthening of telomeres (ALT) and DNA repair by homologous recombination (HR) in the nuclear promyelocytic leukemia (PML) bodies. The cells in repeated MS cycles activate meiotic genes and display holocentric chromosomes characteristic for inverted meiosis (IM). These giant cells acquire an amoeboid phenotype and finally bud the depolyploidized progeny, restarting the mitotic cycling. We suggest the reversible conversion of the telomerase-driven telomere maintenance into ALT coupled with IM at the sub-telomere breakage sites introduced by meiotic nuclease SPO11. All three MS mechanisms converging at telomeres recapitulate the amoeba-like agamic life-cycle, decreasing the mutagenic load and enabling the recovery of recombined, reduced progeny for return into the mitotic cycle.
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The genome of the sea anemone Actinia equina (L.): Meiotic toolkit genes and the question of sexual reproduction. Mar Genomics 2020; 53:100753. [PMID: 32057717 DOI: 10.1016/j.margen.2020.100753] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 02/05/2020] [Accepted: 02/05/2020] [Indexed: 12/15/2022]
Abstract
The beadlet anemone Actinia equina (L.) (Cnidaria: Anthozoa: Actiniaria: Actiniidae) is one of the most familiar organisms of the North European intertidal zone. Once considered a single, morphologically variable species across northern Europe, it is now recognised as one member of a variable species complex. Previous studies of distribution, aggression, allozymes and mitochondrial DNA suggest that the diversity in form and colour within A. equina may hide still unrecognised species diversity. To empower further study of A. equina population genetics and systematics, we sequenced (PacBio Sequel) the genome of a single A. equina individual to produce a high-quality genome assembly (contig N50 = 492,607 bp, 1485 contigs, number of protein coding genes = 47,671, 97% BUSCO completeness). There is debate as to whether A. equina reproduces solely asexually, since no reliable, consistent evidence of sexual reproduction has been found. To gain further insight, we examined the genome for evidence of a 'meiotic toolkit' - genes believed to be found consistently in sexually reproducing organisms - and demonstrate that the A. equina genome appears not to have this full complement. Additionally, Smudgeplot analysis, coupled with high haplotype diversity, indicates this genome assembly to be of ambiguous ploidy, suggesting that A. equina may not be diploid. The suggested polyploid nature of this species coupled with the deficiency in meiotic toolkit genes, indicates that further field and laboratory studies of this species is warranted to understand how this species reproduces and what role ploidy may play in speciation within this speciose genus.
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22
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Maciver SK. Ancestral Eukaryotes Reproduced Asexually, Facilitated by Polyploidy: A Hypothesis. Bioessays 2019; 41:e1900152. [DOI: 10.1002/bies.201900152] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/10/2019] [Indexed: 12/29/2022]
Affiliation(s)
- Sutherland K. Maciver
- Centre for Discovery Brain Sciences, Edinburgh Medical SchoolBiomedical SciencesUniversity of Edinburgh Hugh Robson Building, George Square Edinburgh EH8 9XD Scotland UK
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23
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Genetic and genomic evolution of sexual reproduction: echoes from LECA to the fungal kingdom. Curr Opin Genet Dev 2019; 58-59:70-75. [PMID: 31473482 DOI: 10.1016/j.gde.2019.07.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/28/2019] [Accepted: 07/16/2019] [Indexed: 12/30/2022]
Abstract
Sexual reproduction is vastly diverse and yet highly conserved across the eukaryotic domain. This ubiquity suggests that the last eukaryotic common ancestor (LECA) was sexual. It is hypothesized that several critical processes in sexual reproduction, including cell fusion and meiosis, were acquired during the evolution from the first eukaryotic common ancestor (FECA) to the sexual LECA. However, it is challenging to delineate the exact origin and evolution of sexual reproduction given that both FECA and LECA are extinct. Studies of diverse eukaryotes have helped to shed light on this sexual evolutionary trajectory, revealing that a primordial sexual ploidy cycle likely involved endoreplication followed by concerted chromosome loss and that cell-cell fusion, meiosis, and sex determination later arose to shape modern sexual reproduction. Despite the general conservation of sexual reproduction processes throughout eukaryotes, modern sexual cycles are immensely diverse and complex. This diversity and complexity has become readily apparent in the fungal kingdom with the recent rapid expansion of whole-genome sequencing. This abundance of data, the variety of genetic tools available to manipulate and characterize fungi, and the thorough characterization of many fungal sexual cycles make the fungal kingdom an excellent forum, in which to study the conservation and diversification of sexual reproduction.
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Abstract
Fungi reproduce via both heterothallic outcrossing and homothallic selfing modes, and transitions between the two are common throughout the tree of life. A new study reports that the transition from heterothallism to homothallism is common and has repeatedly punctuated the evolutionary trajectory across a major lineage of the fungal kingdom.
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Affiliation(s)
- Sheng Sun
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Xiaorong Lin
- Department of Microbiology, University of Georgia, Athens, GA 30605, USA
| | - Marco A Coelho
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
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