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He Y, Bader MY, Li D, Stark LR, Li X, Liu X, Yuan Q, Guo S, Fang Z, Wang Z. Relationships among sporophytic and gametophytic traits of 27 subtropical montane moss species. American J of Botany 2023; 110:e16253. [PMID: 37938812 DOI: 10.1002/ajb2.16253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 10/15/2023] [Accepted: 10/16/2023] [Indexed: 11/10/2023]
Abstract
PREMISE Moss sporophytes differ strongly in size and biomass partitioning, potentially reflecting reproductive and dispersal strategies. Understanding how sporophyte traits are coordinated is essential for understanding moss functioning and evolution. This study aimed to answer: (1) how the size and proportions of the sporophyte differ between moss species with and without a prominent central strand in the seta, (2) how anatomical and morphological traits of the seta are related, and (3) how sporophytic biomass relates to gametophytic biomass and nutrient concentrations. METHODS We studied the relationships between seta anatomical and morphological traits, the biomass of seta, capsule, and gametophyte, and carbon, nitrogen, and phosphorus concentrations of 27 subtropical montane moss species. RESULTS (1) Moss species with a prominent central strand in the seta had larger setae and heavier capsules than those without a prominent strand. (2) With increasing seta length, setae became thicker and more rounded for both groups, while in species with a prominent central strand, the ratio of transport-cell area to epidermal area decreased. (3) In both groups, mosses with greater gametophytic biomass tended to have heavier sporophytes, but nitrogen and phosphorus concentrations in the gametophyte were unrelated to sporophytic traits. CONCLUSIONS Our study highlights that the central strand in the seta may have an important functional role and affect the allometry of moss sporophytes. The coordinated variations in sporophyte morphological and anatomical traits follow basic biomechanical principles of cylinder-like structures, and these traits relate only weakly to the gametophytic nutrient concentrations. Research on moss sporophyte functional traits and their relationships to gametophytes is still in its infancy but could provide important insights into their adaptative strategies.
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Affiliation(s)
- Yunyu He
- Shanghai Normal University, Shanghai, 200234, China
| | - Maaike Y Bader
- Ecological Plant Geography, Faculty of Geography, University of Marburg, Marburg, 35032, Germany
| | - Dandan Li
- Shanghai Normal University, Shanghai, 200234, China
| | - Lloyd R Stark
- School of Life Sciences, University of Nevada, Las Vegas, NV, 89154-4004, USA
| | - Xiaoming Li
- China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Xin Liu
- China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Qizhang Yuan
- Shanghai Normal University, Shanghai, 200234, China
| | | | - Zhiqiang Fang
- Sichuan Provincial Academy of Natural Resources Sciences, Chengdu, 610041, China
| | - Zhe Wang
- Shanghai Normal University, Shanghai, 200234, China
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2
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Pannell JR. Sex, sexes, sex roles, and gender in land plants. Am J Bot 2023. [PMID: 37272207 DOI: 10.1002/ajb2.16195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
"When we view gender as an accomplishment, an achieved property of situated conduct, our attention shifts from matters internal to the individual and focuses on interactional and, ultimately, institutional arenas. In one sense, of course, it is individuals who 'do' gender. But it is a situated doing, carried out in the virtual or real presence of others who are presumed to be oriented to its production. Rather than as a property of individuals, we conceive of gender as of an emergent feature of social situations: both as an outcome of and a rationale for various social arrangements and as a means of legitimating one of the most fundamental divisions of society." This article is protected by copyright. All rights reserved.
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Affiliation(s)
- John R Pannell
- Department of Ecology and Evolution, University of Lausanne, Lausanne, 1015, Switzerland
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3
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Pittermann J, Baer A, Campany C, Jansen S, Holmlund H, Schuettpelz E, Mehltreter K, Watkins JE. A reduced role for water transport during the Cenozoic evolution of epiphytic Eupolypod ferns. New Phytol 2023; 237:1745-1758. [PMID: 36484140 DOI: 10.1111/nph.18667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
The Cretaceous-Cenozoic expansion of tropical forests created canopy space that was subsequently occupied by diverse epiphytic communities including Eupolypod ferns. Eupolypods proliferated in this more stressful niche, where lower competition enabled the adaptive radiation of thousands of species. Here, we examine whether xylem traits helped shape the Cenozoic radiation of Eupolypod ferns. We characterized the petiole xylem anatomy of 39 species belonging to the Eupolypod I and Eupolypod II clades occupying the epiphytic, hemiepiphytic, and terrestrial niche, and we assessed vulnerability to embolism in a subset of species. The transition to the canopy was associated with reduced xylem content and smaller tracheid diameters, but no differences were found in species vulnerability to embolism and pit membrane thickness. Phylogenetic analyses support selection for traits associated with reduced water transport in Eupolypod 1 species. We posit that in Eupolypod epiphytes, selection favored water retention via thicker leaves and lower stomatal density over higher rates of water transport. Consequently, lower leaf water loss was coupled with smaller quantities of xylem and narrower tracheid diameters. Traits associated with water conservation were evident in terrestrial Eupolypod 1 ferns and may have predisposed this clade toward radiation in the canopy.
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Affiliation(s)
- Jarmila Pittermann
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, 95060, USA
| | - Alex Baer
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, 95060, USA
| | - Courtney Campany
- Department of Biology, Shepherd University, Shepherdstown, WV, 25443, USA
| | - Steven Jansen
- Institute for Systematic Botany and Ecology, University of Ulm, Ulm, 89081, Germany
| | - Helen Holmlund
- Natural Science Division, Pepperdine University, Malibu, CA, 90263, USA
| | - Eric Schuettpelz
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20560, USA
| | - Klaus Mehltreter
- Red de Ecologia Funcíonal, Instituto de Ecología A.C, Xalapa, Veracruz, 91073, Mexico
| | - James E Watkins
- Department of Biology, Colgate University, Hamilton, NY, 13346, USA
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4
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Patwary ZP, Zhao M, Wang T, Paul NA, Cummins SF. A Proteomic Analysis for the Red Seaweed Asparagopsis taxiformis. Biology (Basel) 2023; 12. [PMID: 36829446 DOI: 10.3390/biology12020167] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/08/2023] [Accepted: 01/10/2023] [Indexed: 01/22/2023]
Abstract
The red seaweed Asparagopsis taxiformis is a promising ruminant feed additive with anti-methanogenic properties that could contribute to global climate change solutions. Genomics has provided a strong foundation for in-depth molecular investigations, including proteomics. Here, we investigated the proteome of A. taxiformis (Lineage 6) in both sporophyte and gametophyte stages, using soluble and insoluble extraction methods. We identified 741 unique non-redundant proteins using a genome-derived database and 2007 using a transcriptome-derived database, which included numerous proteins predicted to be of fungal origin. We further investigated the genome-derived proteins to focus on seaweed-specific proteins. Ontology analysis indicated a relatively large proportion of ion-binding proteins (i.e., iron, zinc, manganese, potassium and copper), which may play a role in seaweed heavy metal tolerance. In addition, we identified 58 stress-related proteins (e.g., heat shock and vanadium-dependent haloperoxidases) and 44 photosynthesis-related proteins (e.g., phycobilisomes, photosystem I, photosystem II and ATPase), which were in general more abundantly identified from female gametophytes. Forty proteins were predicted to be secreted, including ten rhodophyte collagen-alpha-like proteins (RCAPs), which displayed overall high gene expression levels. These findings provide a comprehensive overview of expressed proteins in A. taxiformis, highlighting the potential for targeted protein extraction and functional characterisation for future biodiscovery.
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Matos TM, Cruz R, Peralta DF, Melo-de-Pinna GFDA, dos Santos DYAC. Cuticle structure and chemical composition of waxes in Phaeoceros laevis (L.) Prosk (Notothyladaceae, Anthocerotophyta). Front Plant Sci 2022; 13:785812. [PMID: 36340379 PMCID: PMC9634757 DOI: 10.3389/fpls.2022.785812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 09/26/2022] [Indexed: 06/16/2023]
Abstract
The development of a hydrophobic cuticle covering the epidermis was a crucial evolutionary novelty ensuring the establishment of land plants. However, there is little information about its structure and chemical composition, as well as its functional implications in avascular lineages such as Anthocerotophyta. The main goal of the present study was to compare the gametophyte and sporophyte cuticles of Phaeoceros laevis. Semithin sections were analyzed through light microscopy (LM), cuticle structure was evaluated by transmission electron microscopy (TEM) and epicuticular wax morphology was analyzed by scanning electron microscopy (SEM). Total waxes were analyzed by CG/MS, and the components were identified based on the mass spectra. A thin lipophilic layer was detected on the sporophyte surface, structured as a stratified cuticular layer, similar to the well-known structure described for vascular plants. On the other hand, the gametophyte cuticle was observed only with TEM as a thin osmiophilic layer. SEM analyses showed a film-type wax on the surface of both life phases. The wax layer was eight-fold thicker on the sporophyte (0.8 µg cm-2) than on gametophyte (0.1 µg cm-2). Possible mechanical and/or drought protection are discussed. Fatty acids, primary alcohols, and steroids were identified in both life phases, while the kauren-16-ene diterpene (3%) was detected only on the sporophyte. Although no alkanes were detected in P. laevis, our findings unveil great similarity of the sporophyte cuticle of this hornwort species with the general data described for vascular plants, reinforcing the conservative condition of this character and supporting the previous idea that the biosynthetic machinery involved in the synthesis of wax compounds is conserved since the ancestor of land plants.
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Affiliation(s)
- Tamara Machado Matos
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Rafael Cruz
- School of Biological Sciences, Institute of Molecular Plant Sciences, University of Edinburgh, Edinburgh, United Kingdom
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Sorojsrisom ES, Haller BC, Ambrose BA, Eaton DAR. Selection on the gametophyte: Modeling alternation of generations in plants. Appl Plant Sci 2022; 10:e11472. [PMID: 35495198 PMCID: PMC9039789 DOI: 10.1002/aps3.11472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 03/14/2022] [Indexed: 05/12/2023]
Abstract
PREMISE The degree of gametophyte dependence on the sporophyte life stage is a major feature that differentiates the life cycles of land plants, yet the evolutionary consequences of this difference remain poorly understood. Most evolutionary models assume organisms are either haploid or diploid for their entire lifespan, which is not appropriate for simulating plant life cycles. Here, we introduce shadie (Simulating Haploid-Diploid Evolution), a new, simple Python program for implementing simulations with biphasic life cycles and analyzing their results, using SLiM 3 as a simulation back end. METHODS We implemented evolutionary simulations under three realistic plant life cycle models supported in shadie, using either standardized or biologically realistic parameter settings to test how variation in plant life cycles and sexual systems affects patterns of genome diversity. RESULTS The dynamics of single beneficial mutation fixation did not vary dramatically between different models, but the patterns of spatial variation did differ, demonstrating that different life histories and model parameters affect both genetic diversity and linkage disequilibrium. The rate of linkage disequilibrium decay away from selected sites varied depending on model parameters such as cloning and selfing rates, through their impact on effective population sizes. DISCUSSION Evolutionary simulations are an exciting, underutilized approach in evolutionary research and education. shadie can aid plant researchers in developing null hypotheses, examining theory, and designing empirical studies, in order to investigate the role of the gametophyte life stage, and the effects of variation in plant life cycles, on plant genome evolution.
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Affiliation(s)
- Elissa S. Sorojsrisom
- Department of Ecology, Evolution, and Environmental BiologyColumbia University1200 Amsterdam Ave., Schermerhorn Ext.New York10027USA
- New York Botanical Garden2900 Southern Blvd.BronxNew York10458USA
| | - Benjamin C. Haller
- Department of Computational BiologyCornell University, IthacaNew York14853USA
| | | | - Deren A. R. Eaton
- Department of Ecology, Evolution, and Environmental BiologyColumbia University1200 Amsterdam Ave., Schermerhorn Ext.New York10027USA
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7
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Yang X, Wang X, Yao J, Duan D. Genome-Wide Mapping of Cytosine Methylation Revealed Dynamic DNA Methylation Patterns Associated with Sporophyte Development of Saccharina japonica. Int J Mol Sci 2021; 22:9877. [PMID: 34576045 PMCID: PMC8472486 DOI: 10.3390/ijms22189877] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/27/2021] [Accepted: 09/08/2021] [Indexed: 02/04/2023] Open
Abstract
Cytosine methylation plays vital roles in regulating gene expression and plant development. However, the function of DNA methylation in the development of macroalgae remains unclear. Through the genome-wide bisulfite sequencing of cytosine methylation in holdfast, stipe and blade, we obtained the complete 5-mC methylation landscape of Saccharina japonica sporophyte. Our results revealed that the total DNA methylation level of sporophyte was less than 0.9%, and the content of CHH contexts was dominant. Moreover, the distribution of CHH methylation within the genes exhibited exon-enriched characteristics. Profiling of DNA methylation in three parts revealed the diverse methylation pattern of sporophyte development. These pivotal DMRs were involved in cell motility, cell cycle and cell wall/membrane biogenesis. In comparison with stipe and blade, hypermethylation of mannuronate C5-epimerase in holdfast decreased the transcript abundance, which affected the synthesis of alginate, the key component of cell walls. Additionally, 5-mC modification participated in the regulation of blade and holdfast development by the glutamate content respectively via glutamine synthetase and amidophosphoribosyl transferase, which may act as the epigenetic regulation signal. Overall, our study revealed the global methylation characteristics of the well-defined holdfast, stipe and blade, and provided evidence for epigenetic regulation of sporophyte development in brown macroalgae.
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Affiliation(s)
- Xiaoqi Yang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (X.Y.); (X.W.); (J.Y.)
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiuliang Wang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (X.Y.); (X.W.); (J.Y.)
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266071, China
| | - Jianting Yao
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (X.Y.); (X.W.); (J.Y.)
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266071, China
| | - Delin Duan
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (X.Y.); (X.W.); (J.Y.)
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266071, China
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8
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Yao H, Scornet D, Jam M, Hervé C, Potin P, Oliveira Correia L, Coelho SM, Cock JM. Biochemical characteristics of a diffusible factor that induces gametophyte to sporophyte switching in the brown alga Ectocarpus. J Phycol 2021; 57:742-753. [PMID: 33432598 DOI: 10.1111/jpy.13126] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 11/16/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
The haploid-diploid life cycle of the filamentous brown alga Ectocarpus involves alternation between two independent and morphologically distinct multicellular generations, the sporophyte and the gametophyte. Deployment of the sporophyte developmental program requires two TALE homeodomain transcription factors OUROBOROS and SAMSARA. In addition, the sporophyte generation has been shown to secrete a diffusible factor that can induce uni-spores to switch from the gametophyte to the sporophyte developmental program. Here, we determine optimal conditions for production, storage, and detection of this diffusible factor and show that it is a heat-resistant, high molecular weight molecule. Based on a combined approach involving proteomic analysis of sporophyte-conditioned medium and the use of biochemical tools to characterize arabinogalactan proteins, we present evidence that sporophyte-conditioned medium contains AGP epitopes and suggest that the diffusible factor may belong to this family of glycoproteins.
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Affiliation(s)
- Haiqin Yao
- Algal Genetics Group, UMR 8227, CNRS, Sorbonne Université, UPMC University Paris 06, Paris, France
- Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff, France
| | - Delphine Scornet
- Algal Genetics Group, UMR 8227, CNRS, Sorbonne Université, UPMC University Paris 06, Paris, France
- Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff, France
| | - Murielle Jam
- Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff, France
- Marine Glycobiology, UMR 8227, CNRS, Sorbonne Université, UPMC University Paris 06, Paris, France
| | - Cécile Hervé
- Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff, France
- Marine Glycobiology, UMR 8227, CNRS, Sorbonne Université, UPMC University Paris 06, Paris, France
| | - Philippe Potin
- Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff, France
- Algal Biology and Environmental Interactions, UMR 8227, CNRS, Sorbonne Université, UPMC University Paris 06, Paris, France
| | - Lydie Oliveira Correia
- PAPPSO, INRA, AgroParisTech, Micalis Institute, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Susana M Coelho
- Algal Genetics Group, UMR 8227, CNRS, Sorbonne Université, UPMC University Paris 06, Paris, France
- Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff, France
| | - J Mark Cock
- Algal Genetics Group, UMR 8227, CNRS, Sorbonne Université, UPMC University Paris 06, Paris, France
- Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff, France
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Takechi K, Nagase H, Furuya T, Hattori K, Sato Y, Miyajima K, Higuchi T, Matsuda R, Takio S, Tsukaya H, Takano H. Two atypical ANGUSTIFOLIA without a plant-specific C-terminus regulate gametophore and sporophyte shapes in the moss Physcomitrium (Physcomitrella) patens. Plant J 2021; 105:1390-1399. [PMID: 33280196 DOI: 10.1111/tpj.15121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 11/06/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
ANGUSTIFOLIA (AN) is a plant-specific subfamily of the CtBP/BARS/AN family, characterized by a plant-specific C-terminal domain of approximately 200 amino acids. Previously, we revealed that double knockout (DKO) lines of Physcomitrium (Physcomitrella) patens ANGUSTIFOLIA genes (PpAN1-1 and PpAN1-2) show defects in gametophore height and the lengths of the seta and foot region of sporophytes, by reduced cell elongation. In addition to two canonical ANs, the genome of P. patens has two atypical ANs without a coding region for a plant-specific C-terminus (PpAN2-1 and PpAN2-2); these were investigated in this study. Similar to PpAN1s, both promoters of the PpAN2 genes were highly active in the stems of haploid gametophores and in the middle-to-basal region of young diploid sporophytes that develop into the seta and foot. Analyses of PpAN2-1/2-2 DKO and PpAN quadruple knockout (QKO) lines implied that these four AN genes have partially redundant functions to regulate cell elongation in their expression regions. Transgenic strains harboring P. patens α-tubulin fused to green fluorescent protein, which were generated from a QKO line, showed that the orientation of the microtubules in the gametophore tips in the PpAN QKO lines was unchanged from the wild-type and PpAN1-1/1-2 DKO plants. In addition to both PpAN2-1 and PpAN2-2, short Arabidopsis AN without the C-terminus of 200 amino acids could rescue the Arabidopsis thaliana an-1 phenotypes, implying AN activity is dependent on the N-terminal regions.
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Affiliation(s)
- Katsuaki Takechi
- Faculty of Advanced Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Hiroaki Nagase
- Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Tomoyuki Furuya
- Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
| | - Koro Hattori
- Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan
| | - Yoshikatsu Sato
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, 464-8601, Japan
| | - Kensuke Miyajima
- Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Tomofumi Higuchi
- Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Ryuya Matsuda
- Center for Water Cycle, Marine Environment and Disaster Management, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Susumu Takio
- Faculty of Advanced Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
- Center for Water Cycle, Marine Environment and Disaster Management, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Hirokazu Tsukaya
- Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan
| | - Hiroyoshi Takano
- Faculty of Advanced Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
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Stephan OOH. Implications of ionizing radiation on pollen performance in comparison with diverse models of polar cell growth. Plant Cell Environ 2021; 44:665-691. [PMID: 33124689 DOI: 10.1111/pce.13929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 06/11/2023]
Abstract
Research concerning the effects of ionizing radiation (IR) on plant systems is essential for numerous aspects of human society, as for instance, in terms of agriculture and plant breeding, but additionally for elucidating consequences of radioactive contamination of the ecosphere. This comprehensive survey analyses effects of x- and γ-irradiation on male gametophytes comprising primarily in vitro but also in vivo data of diverse plant species. The IR-dose range for pollen performance was compiled and 50% inhibition doses (ID50 ) for germination and tube growth were comparatively related to physiological characteristics of the microgametophyte. Factors influencing IR-susceptibility of mature pollen and polarized tube growth were evaluated, such as dose-rate, environmental conditions, or species-related variations. In addition, all available reports suggesting bio-positive IR-effects particularly on pollen performance were examined. Most importantly, for the first time influences of IR specifically on diverse phylogenetic models of polar cell growth were comparatively analysed, and thus demonstrated that the gametophytic system of pollen is extremely resistant to IR, more than plant sporophytes and especially much more than comparable animal cells. Beyond that, this study develops hypotheses regarding a molecular basis for the extreme IR-resistance of the plant microgametophyte and highlights its unique rank among organismal systems.
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Affiliation(s)
- Octavian O H Stephan
- Department of Biology, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
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11
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Schoenrock KM, McHugh TA, Krueger-Hadfield SA. Revisiting the 'bank of microscopic forms' in macroalgal-dominated ecosystems. J Phycol 2021; 57:14-29. [PMID: 33135166 DOI: 10.1111/jpy.13092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 10/23/2020] [Indexed: 06/11/2023]
Abstract
Theoretical ecological models, such as succession and facilitation, were defined in terrestrial habitats, and subsequently applied to marine and freshwater habitats in intertidal and then subtidal realms. One such model is the soil seed bank, defined as all viable seeds (or fruits) found near the soil surface that facilitate community restoration/recovery. "Banks of microscopic forms" have been hypothesized in aquatic habitats and recent work from aquaculture has highlighted dormancy in algal life cycle stages. To reinvigorate the discussions about these algal banks, we discuss differences in life cycles, dispersal, and summarize research on banks of macroalgal stages in aquatic ecosystems that may be easier to explore with modern advances in molecular technology. With focus on seminal work in global kelp forest ecosystems, we present a pilot study in northern California as proof of concept that Nereocystis luetkeana and Alaria marginata stages can be detected within kelp forests in the biofilm of rocks and bedrock using targeted primers long after zoospore release. Considering the increased interest in algae as an economic resource, [blue] carbon sink, and as ecosystem engineers, the potential for "banking" macroalgal forms could be a mechanism of resilience and recovery in aquatic populations that have complex life cycles and environmental cues for reproduction. Molecular barcoding is becoming an important tool for identifying banks of macroalgal forms in marine communities. Understanding banks of macroalgal stages, especially in deforested habitats with intense disturbance and grazer pressure, will allow researchers and marine resource managers to facilitate this natural process in recovery of the aquatic system.
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Affiliation(s)
- Kathryn M Schoenrock
- Department of Zoology, Ryan Institute, National University of Ireland, Galway, University Rd., Galway, H91 TK33, Ireland
| | - Tristin Anoush McHugh
- Long Marine Laboratory, Reef Check Foundation, 115 McAllister Road, Santa Cruz, California, 95060, USA
| | - Stacy A Krueger-Hadfield
- Department of Biology, University of Alabama at Birmingham, Campbell Hall, Room 464, Birmingham, Alabama, 35294, USA
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12
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Pandey S, Moradi AB, Dovzhenko O, Touraev A, Palme K, Welsch R. Molecular Control of Sporophyte-Gametophyte Ontogeny and Transition in Plants. Front Plant Sci 2021; 12:789789. [PMID: 35095963 PMCID: PMC8793881 DOI: 10.3389/fpls.2021.789789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 12/23/2021] [Indexed: 05/02/2023]
Abstract
Alternation of generations between a sporophytic and gametophytic developmental stage is a feature common to all land plants. This review will discuss the evolutionary origins of these two developmental programs from unicellular eukaryotic progenitors establishing the ability to switch between haploid and diploid states. We will compare the various genetic factors that regulate this switch and highlight the mechanisms which are involved in maintaining the separation of sporophytic and gametophytic developmental programs. While haploid and diploid stages were morphologically similar at early evolutionary stages, largely different gametophyte and sporophyte developments prevail in land plants and finally allowed the development of pollen as the male gametes with specialized structures providing desiccation tolerance and allowing long-distance dispersal. Moreover, plant gametes can be reprogrammed to execute the sporophytic development prior to the formation of the diploid stage achieved with the fusion of gametes and thus initially maintain the haploid stage. Upon diploidization, doubled haploids can be generated which accelerate modern plant breeding as homozygous plants are obtained within one generation. Thus, knowledge of the major signaling pathways governing this dual ontogeny in land plants is not only required for basic research but also for biotechnological applications to develop novel breeding methods accelerating trait development.
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Affiliation(s)
- Saurabh Pandey
- Faculty of Biology, Institute of Biology II, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Amir Bahram Moradi
- Faculty of Biology, Institute of Biology II, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Oleksandr Dovzhenko
- Faculty of Biology, Institute of Biology II, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- ScreenSYS GmbH, Freiburg, Germany
| | - Alisher Touraev
- National Center for Knowledge and Innovation in Agriculture, Ministry of Agriculture of the Republic of Uzbekistan, Tashkent, Uzbekistan
| | - Klaus Palme
- Faculty of Biology, Institute of Biology II, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- ScreenSYS GmbH, Freiburg, Germany
- BIOSS Center for Biological Signaling Studies, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Ralf Welsch
- Faculty of Biology, Institute of Biology II, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- *Correspondence: Ralf Welsch,
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13
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Paľová M, Ručová D, Goga M, Kolarčik V. Spatial and Temporal Patterns of Endopolyploidy in Mosses. Genes (Basel) 2020; 12:E27. [PMID: 33375487 PMCID: PMC7824635 DOI: 10.3390/genes12010027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 12/14/2022] Open
Abstract
Somatic polyploidy or endopolyploidy is common in the plant kingdom; it ensures growth and allows adaptation to the environment. It is present in the majority of plant groups, including mosses. Endopolyploidy had only been previously studied in about 65 moss species, which represents less than 1% of known mosses. We analyzed 11 selected moss species to determine the spatial and temporal distribution of endopolyploidy using flow cytometry to identify patterns in ploidy levels among gametophytes and sporophytes. All of the studied mosses possessed cells with various ploidy levels in gametophytes, and four of six species investigated in sporophytic stage had endopolyploid sporophytes. The proportion of endopolyploid cells varied among organs, parts of gametophytes and sporophytes, and ontogenetic stages. Higher ploidy levels were seen in basal parts of gametophytes and sporophytes than in apical parts. Slight changes in ploidy levels were observed during ontogenesis in cultivated mosses; the youngest (apical) parts of thalli tend to have lower levels of endopolyploidy. Differences between parts of cauloid and phylloids of Plagiomnium ellipticum and Polytrichum formosum were also documented; proximal parts had higher levels of endopolyploidy than distal parts. Endopolyploidy is spatially and temporally differentiated in the gametophytes of endopolyploid mosses and follows a pattern similar to that seen in angiosperms.
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Affiliation(s)
| | | | | | - Vladislav Kolarčik
- Institute of Biology and Ecology, Faculty of Science, P. J. Šafárik University, Mánesova 23, SK-041 54 Košice, Slovakia; (M.P.); (D.R.); (M.G.)
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14
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Hashida Y, Takechi K, Abiru T, Yabe N, Nagase H, Hattori K, Takio S, Sato Y, Hasebe M, Tsukaya H, Takano H. Two ANGUSTIFOLIA genes regulate gametophore and sporophyte development in Physcomitrella patens. Plant J 2020; 101:1318-1330. [PMID: 31674691 DOI: 10.1111/tpj.14592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 08/06/2019] [Accepted: 10/17/2019] [Indexed: 05/08/2023]
Abstract
In Arabidopsis thaliana the ANGUSTIFOLIA (AN) gene regulates the width of leaves by controlling the diffuse growth of leaf cells in the medio-lateral direction. In the genome of the moss Physcomitrella patens, we found two normal ANs (PpAN1-1 and 1-2). Both PpAN1 genes complemented the A. thaliana an-1 mutant phenotypes. An analysis of spatiotemporal promoter activity of each PpAN1 gene, using transgenic lines that contained each PpAN1-promoter- uidA (GUS) gene, showed that both promoters are mainly active in the stems of haploid gametophores and in the middle to basal region of the young sporophyte that develops into the seta and foot. Analyses of the knockout lines for PpAN1-1 and PpAN1-2 genes suggested that these genes have partially redundant functions and regulate gametophore height by controlling diffuse cell growth in gametophore stems. In addition, the seta and foot were shorter and thicker in diploid sporophytes, suggesting that cell elongation was reduced in the longitudinal direction, whereas no defects were detected in tip-growing protonemata. These results indicate that both PpAN1 genes in P. patens function in diffuse growth of the haploid and diploid generations but not in tip growth. To visualize microtubule distribution in gametophore cells of P. patens, transformed lines expressing P. patens α-tubulin fused to sGFP were generated. Contrary to expectations, the orientation of microtubules in the tips of gametophores in the PpAN1-1/1-2 double-knockout lines was unchanged. The relationships among diffuse cell growth, cortical microtubules and AN proteins are discussed.
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Affiliation(s)
- Yoshikazu Hashida
- Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Katsuaki Takechi
- Faculty of Advanced Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Tomomi Abiru
- Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Noriyuki Yabe
- Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Hiroaki Nagase
- Graduate School of Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Koro Hattori
- Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan
| | - Susumu Takio
- Faculty of Advanced Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
- Center for Water Cycle, Marine Environment and Disaster Management, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
| | - Yoshikatsu Sato
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, 464-8601, Japan
| | - Mitsuyasu Hasebe
- National Institute for Basic Biology and SOKENDAI (Graduate School for Advanced Studies), Okazaki, 444-8585, Japan
| | - Hirokazu Tsukaya
- Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan
| | - Hiroyoshi Takano
- Faculty of Advanced Science and Technology, Kumamoto University, Kurokami, Kumamoto, 860-8555, Japan
- Institute of Pulsed Power Science, Kumamoto University, Kumamoto, 860-8555, Japan
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15
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Harrison MC, Mallon EB, Twell D, Hammond RL. Deleterious Mutation Accumulation in Arabidopsis thaliana Pollen Genes: A Role for a Recent Relaxation of Selection. Genome Biol Evol 2020; 11:1939-1951. [PMID: 31209485 PMCID: PMC6640295 DOI: 10.1093/gbe/evz127] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2019] [Indexed: 12/19/2022] Open
Abstract
In many studies, sex-related genes have been found to evolve rapidly. We therefore expect plant pollen genes to evolve faster than sporophytic genes. In addition, pollen genes are expressed as haploids which can itself facilitate rapid evolution because recessive advantageous and deleterious alleles are not masked by dominant alleles. However, this mechanism is less straightforward to apply in the model plant species Arabidopsis thaliana. For 1 Myr, A. thaliana has been self-compatible, a life history switch that has caused: a reduction in pollen competition, increased homozygosity, and a dilution of masking in diploid expressed, sporophytic genes. In this study, we have investigated the relative strength of selection on pollen genes compared with sporophytic genes in A. thaliana. We present two major findings: 1) before becoming self-compatible, positive selection was stronger on pollen genes than sporophytic genes for A. thaliana and 2) current polymorphism data indicate that selection is weaker on pollen genes compared with sporophytic genes. This weaker selection on pollen genes can in part be explained by their higher tissue specificity, which in outbreeding plants can be outweighed by the effects of haploid expression and pollen competition. These results indicate that since A. thaliana has become self-compatible, selection on pollen genes has become more relaxed. This has led to higher polymorphism levels and a higher build-up of deleterious mutations in pollen genes compared with sporophytic genes.
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16
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Horinouchi Y, Yamaguchi M, Chibana H, Togashi T. Nuclear behavior and roles indicate that Codiolum phase is a sporophyte in Monostroma angicava (Ulotrichales, Ulvophyceae). J Phycol 2019; 55:534-542. [PMID: 30715731 DOI: 10.1111/jpy.12841] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 01/18/2019] [Indexed: 06/09/2023]
Abstract
The life-cycle system of Ulotrichales, a major order of Ulvophyceae, remains controversial because it is unclear whether the Codiolum phase, a characteristic unicellular diploid generation in ulotrichalean algae, is a zygote or a sporophyte. This controversy inhibits the understanding of the diversified life cycles in Ulvophyceae. To distinguish between zygotes and sporophytes, we have to examine not only whether diploid generations function as sporophytes, but also whether mitosis occurs before meiosis in diploid generations. However, the nuclear behavior in the Codiolum phases is largely unknown, probably because no suitable methods are available. Using fluorescent microscopy with ethidium bromide and transmission electron microscopy of cell-wall-dissected specimens, we report the nuclear behavior in the Codiolum phases of an ulotrichalean alga with a representative life cycle, Monostroma angicava. Each vegetative Codiolum phase had a single polyploid nucleus due to endoreduplication, a type of mitosis without nuclear division. During zoosporogenesis, the nucleus had a structure that would be a meiosis-specific complex. We quantitatively showed that Codiolum phases grew extremely large and produced numerous zoospores. Our results suggest that an event comparable to mitosis occurs before meiosis in the Codiolum phase of M. angicava. This nuclear behavior and the functions (growth and zoospore production abilities) correspond to those of sporophytes. Therefore, the life-cycle system of M. angicava is a heteromorphic haplo-diplontic cycle. This system appears to be widely adopted among other ulotrichalean algae.
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Affiliation(s)
- Yusuke Horinouchi
- Marine Biosystems Research Center, Chiba University, Kamogawa, 299-5502, Japan
| | - Masashi Yamaguchi
- Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Hiroji Chibana
- Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Tatsuya Togashi
- Marine Biosystems Research Center, Chiba University, Kamogawa, 299-5502, Japan
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17
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Ruiz-Ruano FJ, Navarro-Domínguez B, Camacho JPM, Garrido-Ramos MA. Characterization of the satellitome in lower vascular plants: the case of the endangered fern Vandenboschia speciosa. Ann Bot 2019; 123:587-599. [PMID: 30357311 PMCID: PMC6417484 DOI: 10.1093/aob/mcy192] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 10/04/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND AIMS Vandenboschia speciosa is a highly vulnerable fern species, with a large genome (10.5 Gb). Haploid gametophytes and diploid sporophytes are perennial, can reproduce vegetatively, and certain populations are composed only of independent gametophytes. These features make this fern a good model: (1) for high-throughput analysis of satellite DNA (satDNA) to investigate possible evolutionary trends in satDNA sequence features; (2) to determine the relative contribution of satDNA and other repetitive DNAs to its large genome; and (3) to analyse whether the reproduction mode or phase alternation between long-lasting haploid and diploid stages influences satDNA abundance or divergence. METHODS We analysed the repetitive fraction of the genome of this species in three different populations (one comprised only of independent gametophytes) using Illumina sequencing and bioinformatic analysis with RepeatExplorer and satMiner. KEY RESULTS The satellitome of V. speciosa is composed of 11 satDNA families, most of them showing a short repeat length and being A + T rich. Some satDNAs had complex repeats composed of sub-repeats, showing high similarity to shorter satDNAs. Three families had particular structural features and highly conserved motifs. SatDNA only amounts to approx. 0.4 % of its genome. Likewise, microsatellites do not represent more than 2 %, but transposable elements (TEs) represent approx. 50 % of the sporophytic genomes. We found high resemblance in satDNA abundance and divergence between both gametophyte and sporophyte samples from the same population and between populations. CONCLUSIONS (1) Longer (and older) satellites in V. speciosa have a higher A + T content and evolve from shorter ones and, in some cases, microsatellites were a source of new satDNAs; (2) the satellitome does not explain the huge genome size in this species while TEs are the major repetitive component of the V. speciosa genome and mostly contribute to its large genome; and (3) reproduction mode or phase alternation between gametophytes and sporophytes does not entail accumulation or divergence of satellites.
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Affiliation(s)
- F J Ruiz-Ruano
- Departamento de Genética, Facultad de Ciencias, Universidad de Granada, Granada, Spain
| | - B Navarro-Domínguez
- Departamento de Genética, Facultad de Ciencias, Universidad de Granada, Granada, Spain
| | - J P M Camacho
- Departamento de Genética, Facultad de Ciencias, Universidad de Granada, Granada, Spain
| | - M A Garrido-Ramos
- Departamento de Genética, Facultad de Ciencias, Universidad de Granada, Granada, Spain
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18
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Perroud PF, Meyberg R, Rensing SA. Physcomitrella patens Reute mCherry as a tool for efficient crossing within and between ecotypes. Plant Biol (Stuttg) 2019; 21 Suppl 1:143-149. [PMID: 29772086 DOI: 10.1111/plb.12840] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/09/2018] [Indexed: 05/21/2023]
Abstract
Physcomitrella patens is a monoecious moss that is predominantly selfing in the wild. Laboratory crossing techniques have been established and crosses between the sequenced Gransden ecotype and the genetically divergent Villersexel ecotype were used for genetic mapping. The recently introduced ecotype Reute has a high fertility rate and is genetically more closely related to the Gransden ecotype than the Villersexel ecotype. Reute sexual reproduction phenology is similar to Gransden, which should allow successful crossing. Using the Reute ecotype and an existing Gransden mutant as a test case, we applied a normalised crossing approach to demonstrate crossing potential between these ecotypes. Also, using a standard transformation approach, we generated Reute fluorescent strains expressing mCherry that allow an easy detection of crossed offspring (sporophyte). We show that Reute can be successfully crossed with a self-infertile DR5:DsRed2 mutant generated in the Gransden background. Using newly established Reute fluorescent strains, we show that they can efficiently fertilise Reute as well as Gransden wild type. The resulting progeny display Mendelian 1:1 segregation of the fluorescent marker(s), demonstrating the suitability of such strains for genetic crossing. Overall our results demonstrate that Reute is highly suitable for genetic crossing. The Reute mCherry strain can be used as a suitable background for offspring selection after crossing.
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Affiliation(s)
- P-F Perroud
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg, Germany
| | - R Meyberg
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg, Germany
| | - S A Rensing
- Plant Cell Biology, Faculty of Biology, University of Marburg, Marburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
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19
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Sigel EM, Schuettpelz E, Pryer KM, Der JP. Overlapping Patterns of Gene Expression Between Gametophyte and Sporophyte Phases in the Fern Polypodium amorphum (Polypodiales). Front Plant Sci 2018; 9:1450. [PMID: 30356815 PMCID: PMC6190754 DOI: 10.3389/fpls.2018.01450] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 09/12/2018] [Indexed: 05/16/2023]
Abstract
Ferns are unique among land plants in having sporophyte and gametophyte phases that are both free living and fully independent. Here, we examine patterns of sporophytic and gametophytic gene expression in the fern Polypodium amorphum, a member of the homosporous polypod lineage that comprises 80% of extant fern diversity, to assess how expression of a common genome is partitioned between two morphologically, ecologically, and nutritionally independent phases. Using RNA-sequencing, we generated transcriptome profiles for three replicates of paired samples of sporophyte leaf tissue and whole gametophytes to identify genes with significant differences in expression between the two phases. We found a nearly 90% overlap in the identity and expression levels of the genes expressed in both sporophytes and gametophytes, with less than 3% of genes uniquely expressed in either phase. We compare our results to those from similar studies to establish how phase-specific gene expression varies among major land plant lineages. Notably, despite having greater similarity in the identity of gene families shared between P. amorphum and angiosperms, P. amorphum has phase-specific gene expression profiles that are more like bryophytes and lycophytes than seed plants. Our findings suggest that shared patterns of phase-specific gene expression among seed-free plants likely reflect having relatively large, photosynthetic gametophytes (compared to the gametophytes of seed plants that are highly reduced). Phylogenetic analyses were used to further investigate the evolution of phase-specific expression for the phototropin, terpene synthase, and MADS-box gene families.
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Affiliation(s)
- Erin M. Sigel
- Department of Biology, University of Louisiana at Lafayette, Lafayette, LA, United States
| | - Eric Schuettpelz
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, United States
| | | | - Joshua P. Der
- Department of Biological Science, California State University Fullerton, Fullerton, CA, United States
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20
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Eppley SM, Rosenstiel TN, Chmielewski MW, Woll SC, Shaw ZM, Shortlidge EE. Rapid population sex-ratio changes in the moss Ceratodon purpureus. Am J Bot 2018; 105:1232-1238. [PMID: 30035817 DOI: 10.1002/ajb2.1128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 05/02/2018] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Sex-ratio variation occurs widely in dioecious plants, but the mechanisms of population sex-ratio bias are poorly understood. In bryophytes, sex ratios are often female biased, and little information is available about how and when bias forms. METHODS To test whether population sex-ratio variation can emerge during the gametophytic phase and is not purely a product of spore sex ratios, we created artificial populations of the moss Ceratodon purpureus, with male- and female-biased sex ratios, and placed half under a stress treatment. We hypothesized that male-majority populations would become female-biased and that stress would increase this transition. After 18 mo, when sporophytes were initially forming, we used sex-specific molecular markers to determine population sex ratios. KEY RESULTS Female-majority populations did not differ significantly from their original bias, whereas male-majority populations became significantly more female biased. The plants had only just produced their first spores, so these sex-ratio changes occurred during the gametophytic generation, as a result of sex-specific growth or survival. Sporophytes occurred only in populations with female-biased final sex ratios, which suggests that females in male-majority populations may have invested energy in ramets rather than in sporophyte production. The stress treatment was mild and had no effect on sex ratio. CONCLUSIONS Our results suggest that female bias can be generated during the gametophytic generation, before plants reach sexual maturity. These results, combined with those of previous work, suggest that both the gametophytic and the sporophytic stages drive population sex ratios in C. purpureus, thus indicating that multiple mechanisms operate to create biased population sex ratios.
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Affiliation(s)
- Sarah M Eppley
- Department of Biology, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
| | - Todd N Rosenstiel
- Department of Biology, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
| | - Matthew W Chmielewski
- Department of Biology, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
| | - S Cody Woll
- Department of Biology, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
| | - Zoë M Shaw
- Department of Biology, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
| | - Erin E Shortlidge
- Department of Biology, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
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21
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Thelander M, Landberg K, Sundberg E. Auxin-mediated developmental control in the moss Physcomitrella patens. J Exp Bot 2018; 69:277-290. [PMID: 28992074 DOI: 10.1093/jxb/erx255] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 06/27/2017] [Indexed: 05/08/2023]
Abstract
The signalling molecule auxin regulates many fundamental aspects of growth and development in plants. We review and discuss what is known about auxin-regulated development in mosses, with special emphasis on the model species Physcomitrella patens. It is well established that mosses and other early diverging plants produce and respond to auxin. By sequencing the P. patens genome, it became clear that it encodes many core proteins important for auxin homeostasis, perception, and signalling, which have also been identified in flowering plants. This suggests that the auxin molecular network was present in the last common ancestor of flowering plants and mosses. Despite fundamental differences in their life cycles, key processes such as organ initiation and outgrowth, branching, tropic responses, as well as cell differentiation, division, and expansion appear to be regulated by auxin in the two lineages. This knowledge paves the way for studies aimed at a better understanding of the origin and evolution of auxin function and how auxin may have contributed to the evolution of land plants.
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Affiliation(s)
- Mattias Thelander
- Department of Plant Biology, Swedish University of Agricultural Sciences, The Linnean Centre for Plant Biology in Uppsala, Sweden
| | - Katarina Landberg
- Department of Plant Biology, Swedish University of Agricultural Sciences, The Linnean Centre for Plant Biology in Uppsala, Sweden
| | - Eva Sundberg
- Department of Plant Biology, Swedish University of Agricultural Sciences, The Linnean Centre for Plant Biology in Uppsala, Sweden
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22
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Hiss M, Meyberg R, Westermann J, Haas FB, Schneider L, Schallenberg-Rüdinger M, Ullrich KK, Rensing SA. Sexual reproduction, sporophyte development and molecular variation in the model moss Physcomitrella patens: introducing the ecotype Reute. Plant J 2017; 90:606-620. [PMID: 28161906 DOI: 10.1111/tpj.13501] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 01/20/2017] [Accepted: 01/24/2017] [Indexed: 05/21/2023]
Abstract
Rich ecotype collections are used for several plant models to unravel the molecular causes of phenotypic differences, and to investigate the effects of environmental adaption and acclimation. For the model moss Physcomitrella patens collections of accessions are available, and have been used for phylogenetic and taxonomic studies, for example, but few have been investigated further for phenotypic differences. Here, we focus on the Reute accession and provide expression profiling and comparative developmental data for several stages of sporophyte development, as well as information on genetic variation via genomic sequencing. We analysed cross-technology and cross-laboratory data to define a confident set of 15 mature sporophyte-specific genes. We find that the standard laboratory strain Gransden produces fewer sporophytes than Reute or Villersexel, although gametangia develop with the same time course and do not show evident morphological differences. Reute exhibits less genetic variation relative to Gransden than Villersexel, yet we found variation between Gransden and Reute in the expression profiles of several genes, as well as variation hot spots and genes that appear to evolve under positive Darwinian selection. We analyzed expression differences between the ecotypes for selected candidate genes in the GRAS transcription factor family, the chalcone synthase family and in genes involved in cell wall modification that are potentially related to phenotypic differences. We confirm that Reute is a P. patens ecotype, and suggest its use for reverse-genetics studies that involve progression through the life cycle and multiple generations.
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Affiliation(s)
- Manuel Hiss
- Plant Cell Biology, Faculty of Biology, University of Marburg, Karl-von-Frisch-Str. 8, 35043, Marburg, Germany
| | - Rabea Meyberg
- Plant Cell Biology, Faculty of Biology, University of Marburg, Karl-von-Frisch-Str. 8, 35043, Marburg, Germany
| | - Jens Westermann
- Plant Cell Biology, Faculty of Biology, University of Marburg, Karl-von-Frisch-Str. 8, 35043, Marburg, Germany
| | - Fabian B Haas
- Plant Cell Biology, Faculty of Biology, University of Marburg, Karl-von-Frisch-Str. 8, 35043, Marburg, Germany
| | - Lucas Schneider
- Plant Cell Biology, Faculty of Biology, University of Marburg, Karl-von-Frisch-Str. 8, 35043, Marburg, Germany
| | | | - Kristian K Ullrich
- Plant Cell Biology, Faculty of Biology, University of Marburg, Karl-von-Frisch-Str. 8, 35043, Marburg, Germany
| | - Stefan A Rensing
- Plant Cell Biology, Faculty of Biology, University of Marburg, Karl-von-Frisch-Str. 8, 35043, Marburg, Germany
- BIOSS Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
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Busta L, Budke JM, Jetter R. The moss Funaria hygrometrica has cuticular wax similar to vascular plants, with distinct composition on leafy gametophyte, calyptra and sporophyte capsule surfaces. Ann Bot 2016; 118:511-22. [PMID: 27489161 PMCID: PMC4998987 DOI: 10.1093/aob/mcw131] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Revised: 03/29/2016] [Accepted: 05/16/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND AND AIMS Aerial surfaces of land plants are covered with a waxy cuticle to protect against water loss. The amount and composition of cuticular waxes on moss surfaces had rarely been investigated. Accordingly, the degree of similarity between moss and vascular plant waxes, and between maternal and offspring moss structure waxes is unknown. To resolve these issues, this study aimed at providing a comprehensive analysis of the waxes on the leafy gametophyte, gametophyte calyptra and sporophyte capsule of the moss Funaria hygrometrica METHODS Waxes were extracted from the surfaces of leafy gametophytes, gametophyte calyptrae and sporophyte capsules, separated by gas chromatography, identified qualitatively with mass spectrometry, and quantified with flame ionization detection. Diagnostic mass spectral peaks were used to determine the isomer composition of wax esters. KEY RESULTS The surfaces of the leafy gametophyte, calyptra and sporophyte capsule of F. hygrometrica were covered with 0·94, 2·0 and 0·44 μg cm(-2) wax, respectively. While each wax mixture was composed of mainly fatty acid alkyl esters, the waxes from maternal and offspring structures had unique compositional markers. β-Hydroxy fatty acid alkyl esters were limited to the leafy gametophyte and calyptra, while alkanes, aldehydes and diol esters were restricted to the sporophyte capsule. Ubiquitous fatty acids, alcohols, fatty acid alkyl esters, aldehydes and alkanes were all found on at least one surface. CONCLUSIONS This is the first study to determine wax coverage (μg cm(-2)) on a moss surface, enabling direct comparisons with vascular plants, which were shown to have an equal amount or more wax than F. hygrometrica Wax ester biosynthesis is of particular importance in this species, and the ester-forming enzyme(s) in different parts of the moss may have different substrate preferences. Furthermore, the alkane-forming wax biosynthesis pathway, found widely in vascular plants, is active in the sporophyte capsule, but not in the leafy gametophyte or calyptra. Overall, wax composition and coverage on F. hygrometrica were similar to those reported for some vascular plant species, suggesting that the underlying biosynthetic processes in plants of both lineages were inherited from a common ancestor.
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Affiliation(s)
- Lucas Busta
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1, Canada
| | - Jessica M Budke
- Department of Plant Biology, University of California - Davis, One Shields Ave., Davis, CA 95616, USA
| | - Reinhard Jetter
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1, Canada Department of Botany, University of British Columbia, 6270 University Boulevard, Vancouver, BC, V6T 1Z4, Canada
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Rose JP, Kriebel R, Sytsma KJ. Shape analysis of moss (Bryophyta) sporophytes: Insights into land plant evolution. Am J Bot 2016; 103:652-62. [PMID: 26944353 DOI: 10.3732/ajb.1500394] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 01/08/2016] [Indexed: 05/05/2023]
Abstract
PREMISE OF THE STUDY The alternation of generations life cycle represents a key feature of land-plant evolution and has resulted in a diverse array of sporophyte forms and modifications in all groups of land plants. We test the hypothesis that evolution of sporangium (capsule) shape of the mosses-the second most diverse land-plant lineage-has been driven by differing physiological demands of life in diverse habitats. This study provides an important conceptual framework for analyzing the evolution of a single, homologous character in a continuous framework across a deep expanse of time, across all branches of the tree of life. METHODS We reconstruct ancestral sporangium shape and ancestral habitat on the largest phylogeny of mosses to date, and use phylogenetic generalized least squares regression to test the association between habitat and sporangium shape. In addition, we examine the association between shifts in sporangium shape and species diversification. RESULTS We demonstrate that sporangium shape is convergent, under natural selection, and associated with habitat type, and that many shifts in speciation rate are associated with shifts in sporangium shape. CONCLUSIONS Our results suggest that natural selection in different microhabitats results in the diversity of sporangium shape found in mosses, and that many increasing shifts in speciation rate result in changes in sporangium shape across their 480 million year history. Our framework provides a way to examine if diversification shifts in other land plants are also associated with massive changes in sporophyte form, among other morphological traits.
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Affiliation(s)
- Jeffrey P Rose
- Department of Botany, University of Wisconsin-Madison, 430 Lincoln Drive, Madison, Wisconsin 53706.
| | - Ricardo Kriebel
- Department of Botany, University of Wisconsin-Madison, 430 Lincoln Drive, Madison, Wisconsin 53706
| | - Kenneth J Sytsma
- Department of Botany, University of Wisconsin-Madison, 430 Lincoln Drive, Madison, Wisconsin 53706
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Lora J, Hormaza JI, Herrero M. The Diversity of the Pollen Tube Pathway in Plants: Toward an Increasing Control by the Sporophyte. Front Plant Sci 2016; 7:107. [PMID: 26904071 PMCID: PMC4746263 DOI: 10.3389/fpls.2016.00107] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 01/20/2016] [Indexed: 05/06/2023]
Abstract
Plants, unlike animals, alternate multicellular diploid, and haploid generations in their life cycle. While this is widespread all along the plant kingdom, the size and autonomy of the diploid sporophyte and the haploid gametophyte generations vary along evolution. Vascular plants show an evolutionary trend toward a reduction of the gametophyte, reflected both in size and lifespan, together with an increasing dependence from the sporophyte. This has resulted in an overlooking of the importance of the gametophytic phase in the evolution of higher plants. This reliance on the sporophyte is most notorious along the pollen tube journey, where the male gametophytes have to travel a long way inside the sporophyte to reach the female gametophyte. Along evolution, there is a change in the scenery of the pollen tube pathway that favors pollen competition and selection. This trend, toward apparently making complicated what could be simple, appears to be related to an increasing control of the sporophyte over the gametophyte with implications for understanding plant evolution.
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Affiliation(s)
- Jorge Lora
- Department of Subtropical Fruit Crops, Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora – University of Málaga – Consejo Superior de Investigaciones CientíficasMálaga, Spain
| | - José I. Hormaza
- Department of Subtropical Fruit Crops, Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora – University of Málaga – Consejo Superior de Investigaciones CientíficasMálaga, Spain
| | - María Herrero
- Department of Pomology, Estación Experimental Aula Dei, Consejo Superior de Investigaciones CientíficasZaragoza, Spain
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Couceiro L, Le Gac M, Hunsperger HM, Mauger S, Destombe C, Cock JM, Ahmed S, Coelho SM, Valero M, Peters AF. Evolution and maintenance of haploid-diploid life cycles in natural populations: The case of the marine brown alga Ectocarpus. Evolution 2015; 69:1808-22. [PMID: 26096000 DOI: 10.1111/evo.12702] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 05/13/2015] [Accepted: 05/26/2015] [Indexed: 11/26/2022]
Abstract
The evolutionary stability of haploid-diploid life cycles is still controversial. Mathematical models indicate that niche differences between ploidy phases may be a necessary condition for the evolution and maintenance of these life cycles. Nevertheless, experimental support for this prediction remains elusive. In the present work, we explored this hypothesis in natural populations of the brown alga Ectocarpus. Consistent with the life cycle described in culture, Ectocarpus crouaniorum in NW France and E. siliculosus in SW Italy exhibited an alternation between haploid gametophytes and diploid sporophytes. Our field data invalidated, however, the long-standing view of an isomorphic alternation of generations. Gametophytes and sporophytes displayed marked differences in size and, conforming to theoretical predictions, occupied different spatiotemporal niches. Gametophytes were found almost exclusively on the alga Scytosiphon lomentaria during spring whereas sporophytes were present year-round on abiotic substrata. Paradoxically, E. siliculosus in NW France exhibited similar habitat usage despite the absence of alternation of ploidy phases. Diploid sporophytes grew both epilithically and epiphytically, and this mainly asexual population gained the same ecological advantage postulated for haploid-diploid populations. Consequently, an ecological interpretation of the niche differences between haploid and diploid individuals does not seem to satisfactorily explain the evolution of the Ectocarpus life cycle.
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Affiliation(s)
- Lucía Couceiro
- CNRS, Sorbonne Universités, UPMC, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, PUCCh, UACH, CS 90074, Place G, Tessier, 29688, Roscoff, France.
| | - Mickael Le Gac
- CNRS, Sorbonne Universités, UPMC, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, PUCCh, UACH, CS 90074, Place G, Tessier, 29688, Roscoff, France
- Current Address: Ifremer, DYNECO PELAGOS, 29280, Plouzané, France
| | - Heather M Hunsperger
- CNRS, Sorbonne Universités, UPMC, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, PUCCh, UACH, CS 90074, Place G, Tessier, 29688, Roscoff, France
- Current Address: Department of Biology, University of Washington, Seattle, Washington, 98195
| | - Stéphane Mauger
- CNRS, Sorbonne Universités, UPMC, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, PUCCh, UACH, CS 90074, Place G, Tessier, 29688, Roscoff, France
| | - Christophe Destombe
- CNRS, Sorbonne Universités, UPMC, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, PUCCh, UACH, CS 90074, Place G, Tessier, 29688, Roscoff, France
| | - J Mark Cock
- CNRS, Sorbonne Universités, UPMC, UMR 7139, Algal Genetics, Station Biologique de Roscoff, Place G, Tessier, 29688, Roscoff, France
| | - Sophia Ahmed
- CNRS, Sorbonne Universités, UPMC, UMR 7139, Algal Genetics, Station Biologique de Roscoff, Place G, Tessier, 29688, Roscoff, France
- Current Address: Department for Plant Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Susana M Coelho
- CNRS, Sorbonne Universités, UPMC, UMR 7139, Algal Genetics, Station Biologique de Roscoff, Place G, Tessier, 29688, Roscoff, France
| | - Myriam Valero
- CNRS, Sorbonne Universités, UPMC, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, PUCCh, UACH, CS 90074, Place G, Tessier, 29688, Roscoff, France
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Szövényi P, Frangedakis E, Ricca M, Quandt D, Wicke S, Langdale JA. Establishment of Anthoceros agrestis as a model species for studying the biology of hornworts. BMC Plant Biol 2015; 15:98. [PMID: 25886741 PMCID: PMC4393856 DOI: 10.1186/s12870-015-0481-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 03/24/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND Plants colonized terrestrial environments approximately 480 million years ago and have contributed significantly to the diversification of life on Earth. Phylogenetic analyses position a subset of charophyte algae as the sister group to land plants, and distinguish two land plant groups that diverged around 450 million years ago - the bryophytes and the vascular plants. Relationships between liverworts, mosses hornworts and vascular plants have proven difficult to resolve, and as such it is not clear which bryophyte lineage is the sister group to all other land plants and which is the sister to vascular plants. The lack of comparative molecular studies in representatives of all three lineages exacerbates this uncertainty. Such comparisons can be made between mosses and liverworts because representative model organisms are well established in these two bryophyte lineages. To date, however, a model hornwort species has not been available. RESULTS Here we report the establishment of Anthoceros agrestis as a model hornwort species for laboratory experiments. Axenic culture conditions for maintenance and vegetative propagation have been determined, and treatments for the induction of sexual reproduction and sporophyte development have been established. In addition, protocols have been developed for the extraction of DNA and RNA that is of a quality suitable for molecular analyses. Analysis of haploid-derived genome sequence data of two A. agrestis isolates revealed single nucleotide polymorphisms at multiple loci, and thus these two strains are suitable starting material for classical genetic and mapping experiments. CONCLUSIONS Methods and resources have been developed to enable A. agrestis to be used as a model species for developmental, molecular, genomic, and genetic studies. This advance provides an unprecedented opportunity to investigate the biology of hornworts.
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Affiliation(s)
- Péter Szövényi
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
- Institute of Systematic Botany, University of Zurich, Zurich, Switzerland.
- Swiss Institute of Bioinformatics, Quartier Sorge-Batiment Genopode, Lausanne, Switzerland.
- MTA-ELTE-MTM Ecology Research Group, ELTE, Biological Institute, Budapest, Hungary.
| | - Eftychios Frangedakis
- Department of Plant Sciences, University of Oxford, South Parks Rd, Oxford, UK.
- Current Address: Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113 0033, Japan.
| | - Mariana Ricca
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
- Swiss Institute of Bioinformatics, Quartier Sorge-Batiment Genopode, Lausanne, Switzerland.
| | - Dietmar Quandt
- Nees-Institut für Biodiversität der Pflanzen, University of Bonn, Meckenheimer Allee 170, D - 53115, Bonn, Germany.
| | - Susann Wicke
- Nees-Institut für Biodiversität der Pflanzen, University of Bonn, Meckenheimer Allee 170, D - 53115, Bonn, Germany.
- Institute for Evolution and Biodiversity, University of Muenster, Huefferstr. 1, 48149, Muenster, Germany.
| | - Jane A Langdale
- Department of Plant Sciences, University of Oxford, South Parks Rd, Oxford, UK.
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McCuaig B, Dufour SC, Raguso RA, Bhatt AP, Marino P. Structural changes in plastids of developing Splachnum ampullaceum sporophytes and relationship to odour production. Plant Biol (Stuttg) 2015; 17:466-473. [PMID: 25213550 PMCID: PMC4346412 DOI: 10.1111/plb.12256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 09/04/2014] [Indexed: 06/03/2023]
Abstract
Many mosses of the family Splachnaceae are entomophilous and rely on flies for spore dispersal. Splachnum ampullaceum produces a yellow- or pink-coloured hypophysis that releases volatile compounds, attracting flies to the mature moss. The biosynthetic sources of the visual and aromatic cues within the hypophysis have not been identified, and may be either symbiotic cyanobacteria or chromoplasts that break down lipids into volatile compounds. Here, we used transmission electron microscopy and gas chromatography-mass spectrometry (GC-MS) to investigate the sources of these attractants, focusing on different tissues and stages of maturation. Microscopy revealed an abundance of plastids within the hypophysis, while no symbiotic bacteria were observed. During plant maturation, plastids differentiated from amyloplasts with large starch granules to photosynthetic chloroplasts and finally to chromoplasts with lipid accumulations. We used GC-MS to identify over 50 volatile organic compounds from mature sporophytes including short-chain oxygenated compounds, unsaturated irregular terpenoids, fatty acid-derived 6- and 8-carbon alcohols and ketones, and the aromatic compounds acetophenone and p-cresol. The hypophysis showed localised production of pungent volatiles, mainly short-chain fermentation compounds and p-cresol. Some of these volatiles have been shown to be produced from lipid oxidase degradation of linolenic acid within chromoplasts. However, other compounds (such as cyclohexanecarboxylic acid esters) may have a microbial origin. Further investigation is necessary to identify the origin of fly attractants in these mosses.
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Affiliation(s)
- B McCuaig
- Department of Biology, Memorial University of Newfoundland, St John's, NL, Canada
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Abstract
UNLABELLED • PREMISE OF THE STUDY Zygotes of Coleochaete are provisioned by the maternal thallus before undergoing 3-5 rounds of division to produce 8-32 zoospores. An understanding of the selective forces favoring postzygotic divisions would be relevant not only to the interpretation of Coleochaete life history but also to the origin of a multicellular diploid phase in embryophytes.• METHODS Simple optimization models are developed of the number of zygotes per maternal thallus and number of zoospores per zygote.• KEY RESULTS Zygotic mitosis is favored once zygotic size exceeds a threshold, but natural selection usually promotes investment in additional zygotes before zygotes reach this threshold. Factors that favor production of fewer, larger zygotes include multiple paternity, low fecundity, and accessory costs of zygote production. Such factors can result in zygotes exceeding the size at which zygotic mitosis becomes profitable.• CONCLUSIONS Coleochaete may possess large zygotes that undergo multiple fission because of accessory costs associated with matrotrophy, including costs of cortical cells and unfertilized oogonia. The unpredictability of fertilization on land is proposed to have increased accessory costs from unfertilized ova and, as a consequence, to have favored the production of larger zygotes that underwent postzygotic division to produce diploid sporophytes.
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Affiliation(s)
- David Haig
- Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, Massachusetts 02138 USA
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Jung CH, O'Brien M, Singh MB, Bhalla PL. Epigenetic landscape of germline specific genes in the sporophyte cells of Arabidopsis thaliana. Front Plant Sci 2015; 6:328. [PMID: 26029228 PMCID: PMC4429549 DOI: 10.3389/fpls.2015.00328] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 04/27/2015] [Indexed: 05/15/2023]
Abstract
In plants, the germline lineages arise in later stages of life cycle as opposed to animals where both male and female germlines are set aside early in development. This developmental divergence is associated with germline specific or preferential expression of a subset of genes that are normally repressed for the rest of plant life cycle. The gene regulatory mechanisms involved in such long-term suppression and short-term activation in plant germline remain vague. Thus, we explored the nature of epigenetic marks that are likely associated with long-term gene repression in the non-germline cells. We accessed available Arabidopsis genome-wide DNA methylation and histone modification data and queried it for epigenetic marks associated with germline genes: genes preferentially expressed in sperm cells, egg cells, synergid cells, central cells, antipodal cells or embryo sac or genes that are with enriched expression in two or more of female germline tissues. The vast majority of germline genes are associated with repression-related epigenetic histone modifications in one or more non-germline tissues, among which H3K9me2 and H3K27me3 are the most widespread repression-related marks. Interestingly, we show here that the repressive epigenetic mechanisms differ between male and female germline genes. We also highlight the diverse states of epigenetic marks in different non-germline tissues. Some germline genes also have activation-related marks in non-germline tissues, and the proportion of such genes is higher for female germline genes. Germline genes include 30 transposable element (TE) loci, to which a large number of 24-nt long small interfering RNAs were mapped, suggesting that these small RNAs take a role in suppressing them in non-germline tissues. The data presented here suggest that the majority of Arabidopsis gamete-preferentially/-enriched genes bear repressive epigenetic modifications or regulated by small RNAs.
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Affiliation(s)
- Chol Hee Jung
- Plant Molecular Biology and Biotechnology Laboratory, Melbourne School of Land and Environment, The University of MelbourneParkville, VIC, Australia
- VLSCI Life Sciences Computation Centre, The University of MelbourneParkville, VIC, Australia
| | - Martin O'Brien
- Plant Molecular Biology and Biotechnology Laboratory, Melbourne School of Land and Environment, The University of MelbourneParkville, VIC, Australia
| | - Mohan B. Singh
- Plant Molecular Biology and Biotechnology Laboratory, Melbourne School of Land and Environment, The University of MelbourneParkville, VIC, Australia
| | - Prem L. Bhalla
- Plant Molecular Biology and Biotechnology Laboratory, Melbourne School of Land and Environment, The University of MelbourneParkville, VIC, Australia
- *Correspondence: Prem L. Bhalla, Melbourne School of Land and Environment, The University of Melbourne, Building 142, Royal Parade, Parkville, VIC 3010, Australia
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Frank MH, Scanlon MJ. Transcriptomic evidence for the evolution of shoot meristem function in sporophyte-dominant land plants through concerted selection of ancestral gametophytic and sporophytic genetic programs. Mol Biol Evol 2014; 32:355-67. [PMID: 25371433 DOI: 10.1093/molbev/msu303] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Alternation of generations, in which the haploid and diploid stages of the life cycle are each represented by multicellular forms that differ in their morphology, is a defining feature of the land plants (embryophytes). Anciently derived lineages of embryophytes grow predominately in the haploid gametophytic generation from apical cells that give rise to the photosynthetic body of the plant. More recently evolved plant lineages have multicellular shoot apical meristems (SAMs), and photosynthetic shoot development is restricted to the sporophyte generation. The molecular genetic basis for this evolutionary shift from gametophyte-dominant to sporophyte-dominant life cycles remains a major question in the study of land plant evolution. We used laser microdissection and next generation RNA sequencing to address whether angiosperm meristem patterning genes expressed in the sporophytic SAM of Zea mays are expressed in the gametophytic apical cells, or in the determinate sporophytes, of the model bryophytes Marchantia polymorpha and Physcomitrella patens. A wealth of upregulated genes involved in stem cell maintenance and organogenesis are identified in the maize SAM and in both the gametophytic apical cell and sporophyte of moss, but not in Marchantia. Significantly, meiosis-specific genetic programs are expressed in bryophyte sporophytes, long before the onset of sporogenesis. Our data suggest that this upregulated accumulation of meiotic gene transcripts suppresses indeterminate cell fate in the Physcomitrella sporophyte, and overrides the observed accumulation of meristem patterning genes. A model for the evolution of indeterminate growth in the sporophytic generation through the concerted selection of ancestral meristem gene programs from gametophyte-dominant lineages is proposed.
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Eeckhout S, Leroux O, Willats WGT, Popper ZA, Viane RLL. Comparative glycan profiling of Ceratopteris richardii 'C-Fern' gametophytes and sporophytes links cell-wall composition to functional specialization. Ann Bot 2014; 114:1295-307. [PMID: 24699895 PMCID: PMC4195545 DOI: 10.1093/aob/mcu039] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 02/14/2014] [Indexed: 05/05/2023]
Abstract
BACKGROUND AND AIMS Innovations in vegetative and reproductive characters were key factors in the evolutionary history of land plants and most of these transformations, including dramatic changes in life cycle structure and strategy, necessarily involved cell-wall modifications. To provide more insight into the role of cell walls in effecting changes in plant structure and function, and in particular their role in the generation of vascularization, an antibody-based approach was implemented to compare the presence and distribution of cell-wall glycan epitopes between (free-living) gametophytes and sporophytes of Ceratopteris richardii 'C-Fern', a widely used model system for ferns. METHODS Microarrays of sequential diamino-cyclohexane-tetraacetic acid (CDTA) and NaOH extractions of gametophytes, spores and different organs of 'C-Fern' sporophytes were probed with glycan-directed monoclonal antibodies. The same probes were employed to investigate the tissue- and cell-specific distribution of glycan epitopes. KEY RESULTS While monoclonal antibodies against pectic homogalacturonan, mannan and xyloglucan widely labelled gametophytic and sporophytic tissues, xylans were only detected in secondary cell walls of the sporophyte. The LM5 pectic galactan epitope was restricted to sporophytic phloem tissue. Rhizoids and root hairs showed similarities in arabinogalactan protein (AGP) and xyloglucan epitope distribution patterns. CONCLUSIONS The differences and similarities in glycan cell-wall composition between 'C-Fern' gametophytes and sporophytes indicate that the molecular design of cell walls reflects functional specialization rather than genetic origin. Glycan epitopes that were not detected in gametophytes were associated with cell walls of specialized tissues in the sporophyte.
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Affiliation(s)
- Sharon Eeckhout
- Research Group Pteridology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium
| | - Olivier Leroux
- Research Group Pteridology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium Botany and Plant Science and The Ryan Institute for Environmental, Marine and Energy Research, School of Natural Sciences, National University of Ireland Galway, University Road, Galway, Ireland
| | - William G T Willats
- Department of Plant Biology and Biochemistry, Faculty of Life Sciences, University of Copenhagen, Buelowsvej 17-1870 Frederiksberg, Denmark
| | - Zoë A Popper
- Botany and Plant Science and The Ryan Institute for Environmental, Marine and Energy Research, School of Natural Sciences, National University of Ireland Galway, University Road, Galway, Ireland
| | - Ronald L L Viane
- Research Group Pteridology, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium
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O’Donoghue MT, Chater C, Wallace S, Gray JE, Beerling DJ, Fleming AJ. Genome-wide transcriptomic analysis of the sporophyte of the moss Physcomitrella patens. J Exp Bot 2013; 64:3567-81. [PMID: 23888066 PMCID: PMC3745722 DOI: 10.1093/jxb/ert190] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Bryophytes, the most basal of the extant land plants, diverged at least 450 million years ago. A major feature of these plants is the biphasic alternation of generations between a dominant haploid gametophyte and a minor diploid sporophyte phase. These dramatic differences in form and function occur in a constant genetic background, raising the question of whether the switch from gametophyte-to-sporophyte development reflects major changes in the spectrum of genes being expressed or alternatively whether only limited changes in gene expression occur and the differences in plant form are due to differences in how the gene products are put together. This study performed replicated microarray analyses of RNA from several thousand dissected and developmentally staged sporophytes of the moss Physcomitrella patens, allowing analysis of the transcriptomes of the sporophyte and early gametophyte, as well as the early stages of moss sporophyte development. The data indicate that more significant changes in transcript profile occur during the switch from gametophyte to sporophyte than recently reported, with over 12% of the entire transcriptome of P. patens being altered during this major developmental transition. Analysis of the types of genes contributing to these differences supports the view of the early sporophyte being energetically and nutritionally dependent on the gametophyte, provides a profile of homologues to genes involved in angiosperm stomatal development and physiology which suggests a deeply conserved mechanism of stomatal control, and identifies a novel series of transcription factors associated with moss sporophyte development.
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Affiliation(s)
| | - Caspar Chater
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - Simon Wallace
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Julie E. Gray
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | - David J. Beerling
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Andrew J. Fleming
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
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Huan L, He L, Zhang B, Niu J, Lin A, Wang G. AFLP and SCAR markers associated with the sex in Gracilaria lemaneiformis (Rhodophyta). J Phycol 2013; 49:728-732. [PMID: 27007205 DOI: 10.1111/jpy.12082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 03/02/2013] [Indexed: 06/05/2023]
Abstract
Gracilaria lemaneiformis (Bory de Saint-Vincent) Greville, an important marine alga, has great economic and nutritional value. However, during the nonreproductive period, it is difficult to distinguish the sporophyte, male gametophyte, and female gametophyte from each other by appearance. Amplified fragment length polymorphism (AFLP) is a multilocus marker technique, which was used in this study to identify markers associated with G. lemaneiformis sex type. By applying 80 primer combinations in the screening process, three fragments were found that were specific to male or female forms of the alga. A 173 bp band and an 89 bp band were found in the sporophyte and the male gametophyte by using primer E-AGG/M-CGT. E-ACC/M-CGG was used to amplify a 118 bp specific fragment in the sporophyte and the female gametophyte. Sequence characterized amplified region (SCAR) primers were designed and showed the expected bands at the corresponding stages. This suggested that the SCAR markers that had been developed were successful. The joint use of the three primer pairs allowed us to characterize sex and the G. lemaneiformis developmental phase in the nondescript stages. Rapid gender testing is expected to improve cross-breeding experiments and other genetic research in this economically important seaweed.
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Affiliation(s)
- Li Huan
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
- College of Earth Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Linwen He
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Baoyu Zhang
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Jianfeng Niu
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Apeng Lin
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Guangce Wang
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
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Pires ND, Yi K, Breuninger H, Catarino B, Menand B, Dolan L. Recruitment and remodeling of an ancient gene regulatory network during land plant evolution. Proc Natl Acad Sci U S A 2013; 110:9571-6. [PMID: 23690618 DOI: 10.1073/pnas.1305457110] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The evolution of multicellular organisms was made possible by the evolution of underlying gene regulatory networks. In animals, the core of gene regulatory networks consists of kernels, stable subnetworks of transcription factors that are highly conserved in distantly related species. However, in plants it is not clear when and how kernels evolved. We show here that RSL (ROOT HAIR DEFECTIVE SIX-LIKE) transcription factors form an ancient land plant kernel controlling caulonema differentiation in the moss Physcomitrella patens and root hair development in the flowering plant Arabidopsis thaliana. Phylogenetic analyses suggest that RSL proteins evolved in aquatic charophyte algae or in early land plants, and have been conserved throughout land plant radiation. Genetic and transcriptional analyses in loss of function A. thaliana and P. patens mutants suggest that the transcriptional interactions in the RSL kernel were remodeled and became more hierarchical during the evolution of vascular plants. We predict that other gene regulatory networks that control development in derived groups of plants may have originated in the earliest land plants or in their ancestors, the Charophycean algae.
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Coelho SM, Godfroy O, Arun A, Le Corguillé G, Peters AF, Cock JM. Genetic regulation of life cycle transitions in the brown alga Ectocarpus. Plant Signal Behav 2011; 6:1858-60. [PMID: 22067105 PMCID: PMC3329369 DOI: 10.4161/psb.6.11.17737] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The life cycle of an organism is one of its most elemental features, underpinning a broad range of phenomena including developmental processes, reproductive fitness, mode of dispersal and adaptation to the local environment. Life cycle modification may have played an important role during the evolution of several eukaryotic groups, including the terrestrial plants. Brown algae are potentially interesting models to study life cycle evolution because this group exhibits a broad range of different life cycles. Currently, life cycle studies are focused on the emerging brown algal model Ectocarpus. Two life cycle mutants have been described in this species, both of which cause the sporophyte generation to exhibit gametophyte characteristics. The ouroboros mutation is particularly interesting because it induces complete conversion of the sporophyte generation into a functional, gamete-producing gametophyte, a class of mutation that has not been described so far in other systems. Analysis of Ectocarpus life cycle mutants is providing insights into several life-cycle-related processes including parthenogenesis, symmetric/asymmetric initial cell divisions and sex determination.
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Affiliation(s)
- Susana M. Coelho
- CNRS, Station Biologique de Roscoff; Roscoff, France
- Université Pierre et Marie Curie; Paris France
| | - Olivier Godfroy
- CNRS, Station Biologique de Roscoff; Roscoff, France
- Université Pierre et Marie Curie; Paris France
| | - Alok Arun
- CNRS, Station Biologique de Roscoff; Roscoff, France
- Université Pierre et Marie Curie; Paris France
| | - Gildas Le Corguillé
- Service Informatique et Génomique, Station Biologique de Roscoff; Roscoff, France
| | | | - J. Mark Cock
- CNRS, Station Biologique de Roscoff; Roscoff, France
- Université Pierre et Marie Curie; Paris France
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Wubs ERJ, de Groot GA, During HJ, Vogel JC, Grundmann M, Bremer P, Schneider H. Mixed mating system in the fern Asplenium scolopendrium: implications for colonization potential. Ann Bot 2010; 106:583-90. [PMID: 20682575 PMCID: PMC2944980 DOI: 10.1093/aob/mcq157] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
BACKGROUND AND AIMS Human-mediated environmental change is increasing selection pressure for the capacity in plants to colonize new areas. Habitat fragmentation combined with climate change, in general, forces species to colonize areas over longer distances. Mating systems and genetic load are important determinants of the establishment and long-term survival of new populations. Here, the mating system of Asplenium scolopendrium, a diploid homosporous fern species, is examined in relation to colonization processes. METHODS A common environment experiment was conducted with 13 pairs of sporophytes, each from a different site. Together they constitute at least nine distinct genotypes, representing an estimated approx. 95 % of the non-private intraspecific genetic variation in Europe. Sporophyte production was recorded for gametophytes derived from each parent sporophyte. Gametophytes were grown in vitro in three different ways: (I) in isolation, (II) with a gametophyte from a different sporophyte within the same site or (III) with a partner from a different site. KEY RESULTS Sporophyte production was highest in among-site crosses (III), intermediate in within-site crosses (II) and was lowest in isolated gametophytes (I), strongly indicating inbreeding depression. However, intragametophytic selfing was observed in most of the genotypes tested (eight out of nine). CONCLUSIONS The results imply a mixed mating system in A. scolopendrium, with outcrossing when possible and occasional selfing when needed. Occasional intragametophytic selfing facilitates the successful colonization of new sites from a single spore. The resulting sporophyte, which will be completely homozygous, will shed large amounts of spores over time. Each year this creates a bed of gametophytes in the vicinity of the parent. Any unrelated spore which arrives is then selectively favoured to reproduce and contribute its genes to the new population. Thus, while selfing facilitates initial colonization success, inbreeding depression promotes genetically diverse populations through outcrossing. The results provide further evidence against the overly simple dichotomous distinction of fern species as either selfing or outcrossing.
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Affiliation(s)
- E. R. Jasper Wubs
- Ecology and Biodiversity group, Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - G. Arjen de Groot
- Ecology and Biodiversity group, Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
- For correspondence. E-mail
| | - Heinjo J. During
- Ecology and Biodiversity group, Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Johannes C. Vogel
- Department of Botany, Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Michael Grundmann
- Department of Botany, Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Piet Bremer
- Nature Conservation and Plant Ecology group, Wageningen University, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands
| | - Harald Schneider
- Department of Botany, Natural History Museum, Cromwell Road, London SW7 5BD, UK
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Abstract
Elevated irradiance has a profound effect on the successful dispersal and establishment of kelp zoospores, affecting their physiology and viability. The research to date, however, has been on zoospores localized near the benthos, with little attention on the importance of vertical transportation and subsequent exposure to increased irradiance. Therefore, we wanted to investigate the effects of exposure to high irradiance on the reproductive planktonic life-history stages of kelps Macrocystis pyrifera (L.) C. Agardh and Pterygophora californica Rupr. Zoospores of both species were exposed to different irradiances (75, 275, 575, 1,025 μmol photons · m(-2) · s(-1) ) over varying durations (1, 2, 4, 8, 12 h) and subsequently monitored for settlement competency, gametophyte development, and reproductive viability. Settlement success for M. pyrifera was uniform throughout all irradiance × time treatments, while settlement for P. californica decreased with increasing exposure time but not irradiance, although settlement was generally reduced at the highest irradiance level. Following zoospore settlement, germ tube development was visible in the gametophytes of both species within 1 week, although a significant decline of germ tube density in P. californica was observed with increasing irradiance. Similarly, a decrease in germ tube development with increasing exposure was observed across all irradiance levels for M. pyrifera, but irradiance itself was not significant. Further development into embryonic sporophytes was remarkably similar to gametophyte development, suggesting that the effect of exposure of kelp zoospores to high irradiance on subsequent sporophyte production is mediated through gametophyte development as well as zoospore survival.
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Affiliation(s)
- Damien K Cie
- Department of Biology, San Diego State University, 5500 Campanile Drive, San Diego, California 92182, USA
| | - Matthew S Edwards
- Department of Biology, San Diego State University, 5500 Campanile Drive, San Diego, California 92182, USA
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Choi HG, Kim YS, Lee SJ, Nam KW. Growth and reproductive patterns of Undaria pinnatifida sporophytes in a cultivation farm in Busan, Korea. J Appl Phycol 2007; 19:131-138. [PMID: 19396348 PMCID: PMC2668580 DOI: 10.1007/s10811-006-9119-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Accepted: 06/30/2006] [Indexed: 05/27/2023]
Abstract
Monthly growth and reproduction of Undaria pinnatifida sporophytes were examined over a period of 5 months in a cultivation farm in Korea. A total of 11 characters of Undaria were measured to determine a reliable morphological character representing its growth and reproduction. Plant weight of Undaria sporophytes increased steadily over the experimental period, but it increased in four different ways. Undaria pinnatifida increased body weight by growth in length and width (October-early December), and by growth in width with the thickening of blade and stipe when sporophytes began to be fertile (December-January). In the middle of January, growth in length and width had almost stopped with the maturation of Undaria sporophytes. Finally, the weight of Undaria increased again by growth in width at the end of February. Present results indicate that Undaria sporophytes increase body weight by growth in length and width at different times, and the relationship between reproduction and vegetative growth is exclusive. Plant weight was positively correlated and fitted well with stipe width and blade width. The blade of Undaria was very thin (ca. 254 mum) and breakable by wave action, but its stipe was strong and relatively thick (ca. 8.7 mm). Furthermore, the fertility of U. pinnatifida was fitted better with stipe width than blade width. Thus, we suggest that the stipe width is the most feasible character with which to estimate the growth and reproduction of U. pinnatifida sporophytes in the cultivation farm.
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Affiliation(s)
- Han Gil Choi
- Faculty of Biological Science and Research Institute for Basic Science, Wonkwang University, Iksan, Jeonbuk 570-749 South Korea
| | - Young Sik Kim
- School of Marine Life Science, Kunsan National University, Kusan, Jeonbuk 573-701 South Korea
| | - Soon Jeong Lee
- Department of Marine Biology, Pukyong National University, Busan, 608-737 South Korea
| | - Ki Wan Nam
- Department of Marine Biology, Pukyong National University, Busan, 608-737 South Korea
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Stark LR, Oliver MJ, Mishler BD, McLetchie DN. Generational differences in response to desiccation stress in the desert moss Tortula inermis. Ann Bot 2007; 99:53-60. [PMID: 17098752 PMCID: PMC2802979 DOI: 10.1093/aob/mcl238] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2006] [Revised: 08/30/2006] [Accepted: 09/19/2006] [Indexed: 05/08/2023]
Abstract
BACKGROUND AND AIMS Active growth in post-embryonic sporophytes of desert mosses is restricted to the cooler, wetter months. However, most desert mosses have perennial gametophytes. It is hypothesized that these life history patterns are due, in part, to a reduced desiccation tolerance for sporophytes relative to gametophytes. METHODS Gametophytes with attached post-embryonic sporophytes of Tortula inermis (early seta elongation phenophase) were exposed to two levels of desiccation stress, one rapid-dry cycle and two rapid-dry cycles, then moistened and allowed to recover, resume development, and/or regenerate for 35 d in a growth chamber. KEY RESULTS Gametophytes tolerated the desiccation treatments well, with 93 % survival through regenerated shoot buds and/or protonemata. At the high stress treatment, a significantly higher frequency of burned leaves and browned shoots occurred. Sporophytes were far more sensitive to desiccation stress, with only 23 % surviving after the low desiccation stress treatment, and 3 % surviving after the high desiccation stress treatment. While the timing of protonemal production and sporophytic phenophases was relatively unaffected by desiccation stress, shoots exposed to one rapid-dry cycle produced shoots more rapidly than shoots exposed to two rapid-dry cycles. CONCLUSIONS It is concluded that sporophytes of Tortula inermis are more sensitive to rapid drying than are maternal gametophytes, and that sporophyte abortion in response to desiccation results from either reduced desiccation tolerance of sporophytes relative to gametophytes, or from a termination of the sporophyte on the part of the gametophyte in response to stress.
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Affiliation(s)
- Lloyd R Stark
- School of Life Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, NV 89154-4004, USA.
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McLETCHIE DNICHOLAS, STARK LLOYDR. Sporophyte and gametophyte generations differ in their thermotolerance response in the moss Microbryum. Ann Bot 2006; 97:505-11. [PMID: 16478767 PMCID: PMC2803666 DOI: 10.1093/aob/mcl011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND AIMS Actively growing post-embryonic sporophytes of desert mosses are restricted to the cooler, wetter months. However, most desert mosses have perennial gametophytes. It is hypothesized that these life history patterns are due in part to a reduced thermotolerance for sporophytes relative to gametophytes. METHODS Gametophytes with attached embryonic sporophytes of Microbryum starckeanum were exposed whilst desiccated to thermal episodes of 35 degrees C (1 hr), 55 degrees C (1 hr), 75 degrees C (1 hr) and 75 degrees C (3 hr), then moistened and allowed to recover for 35 d in a growth chamber. KEY RESULTS All of the gametophytes survived the thermal exposures and produced protonemata, with the majority also producing shoot buds. Symptoms of gametophytic stress (leaf burning and discoloration of entire shoots) were present in lower frequencies in the 55 degrees C exposure. Sporophyte resumption of growth and maturation to meiosis were significantly negatively affected by thermal treatment. Not a single sporophyte exposed to the two higher thermal treatments (75 degrees C for 1 h and 75 degrees C for 3 h) survived to meiosis, and those sporophytes exposed to 75 degrees C that survived to the post-embryonic phenophase took significantly longer to reach this phase. Furthermore, among the thermal treatments where some capsules reached maturity (35 degrees C and 55 degrees C), maternal shoots that produced a meiotic capsule took longer to regenerate through protonemata than maternal shoots aborting their sporophyte, suggestive of a resource trade-off between generations. CONCLUSIONS Either (1) the inherent sporophyte thermotolerance is quite low even in this desert moss, and/or (2) a gametophytic thermal stress response controls sporophyte viability.
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Affiliation(s)
- D. NICHOLAS McLETCHIE
- Department of Biology, 101 Morgan Building, University of Kentucky, Lexington, KY 40506-0225, USA and Department of Biological Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, NV 89154-4004, USA
| | - LLOYD R. STARK
- Department of Biology, 101 Morgan Building, University of Kentucky, Lexington, KY 40506-0225, USA and Department of Biological Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, NV 89154-4004, USA
- For correspondence. E-mail
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Shaw AJ. Antagonistic pleiotropy and the evolution of alternate generations. New Phytol 2001; 152:365-368. [PMID: 33862985 DOI: 10.1046/j.0028-646x.2001.00286.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- A Jonathan Shaw
- Department of Biology, Duke University, Durham, NC 27708, USA(tel +1 919 6607 344; fax +1 010 6607 293;email )
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