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Mizuta Y, Sakakibara D, Nagahara S, Kaneshiro I, Nagae TT, Kurihara D, Higashiyama T. Deep imaging reveals dynamics and signaling in one-to-one pollen tube guidance. EMBO Rep 2024; 25:2529-2549. [PMID: 38773320 PMCID: PMC11169409 DOI: 10.1038/s44319-024-00151-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 04/09/2024] [Accepted: 04/18/2024] [Indexed: 05/23/2024] Open
Abstract
In the pistil of flowering plants, each ovule usually associates with a single pollen tube for fertilization. This one-to-one pollen tube guidance, which contributes to polyspermy blocking and efficient seed production, is largely different from animal chemotaxis of many sperms to one egg. However, the functional mechanisms underlying the directional cues and polytubey blocks in the depths of the pistil remain unknown. Here, we develop a two-photon live imaging method to directly observe pollen tube guidance in the pistil of Arabidopsis thaliana, clarifying signaling and cellular behaviors in the one-to-one guidance. Ovules are suggested to emit multiple signals for pollen tubes, including an integument-dependent directional signal that reaches the inner surface of the septum and adhesion signals for emerged pollen tubes on the septum. Not only FERONIA in the septum but ovular gametophytic FERONIA and LORELEI, as well as FERONIA- and LORELEI-independent repulsion signal, are involved in polytubey blocks on the ovular funiculus. However, these funicular blocks are not strictly maintained in the first 45 min, explaining previous reports of polyspermy in flowering plants.
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Affiliation(s)
- Yoko Mizuta
- Institute for Advanced Research (IAR), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.
| | - Daigo Sakakibara
- Division of Biological Sciences, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan
| | - Shiori Nagahara
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Ikuma Kaneshiro
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
- Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan
- Research Center for Computational Science, Institute for Molecular Science, National Institutes of Natural Sciences, 38 Nishigo-Naka, Myodaiji, Okazaki, 444-8585, Japan
| | - Takuya T Nagae
- Division of Biological Sciences, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan
| | - Daisuke Kurihara
- Institute for Advanced Research (IAR), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Tetsuya Higashiyama
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
- Division of Biological Sciences, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bukyo-ku, Tokyo, 113-0033, Japan
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Binmöller L, Volkert C, Kiefer C, Zühl L, Slawinska MW, Loreth A, Nauerth BH, Ibberson D, Martinez R, Mandakova TM, Zipper R, Schmidt A. Differential expression and evolutionary diversification of RNA helicases in Boechera sexual and apomictic reproduction. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2451-2469. [PMID: 38263359 DOI: 10.1093/jxb/erae026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 01/22/2024] [Indexed: 01/25/2024]
Abstract
In higher plants, sexual reproduction is characterized by meiosis of the first cells of the germlines, and double fertilization of the egg and central cell after gametogenesis. In contrast, in apomicts of the genus Boechera, meiosis is omitted or altered and only the central cell requires fertilization, while the embryo forms parthenogenetically from the egg cell. To deepen the understanding of the transcriptional basis underlying these differences, we applied RNA-seq to compare expression in reproductive tissues of different Boechera accessions. This confirmed previous evidence of an enrichment of RNA helicases in plant germlines. Furthermore, few RNA helicases were differentially expressed in female reproductive ovule tissues harboring mature gametophytes from apomictic and sexual accessions. For some of these genes, we further found evidence for a complex recent evolutionary history. This included a homolog of Arabidopsis thaliana FASCIATED STEM4 (FAS4). In contrast to AtFAS4, which is a single-copy gene, FAS4 is represented by three homologs in Boechera, suggesting a potential for subfunctionalization to modulate reproductive development. To gain first insights into functional roles of FAS4, we studied Arabidopsis lines carrying mutant alleles. This identified the crucial importance of AtFAS4 for reproduction, as we observed developmental defects and arrest during male and female gametogenesis.
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Affiliation(s)
- Laura Binmöller
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
| | - Christopher Volkert
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
| | - Christiane Kiefer
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
| | - Luise Zühl
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
| | - Magdalena W Slawinska
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
| | - Anna Loreth
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
| | - Berit H Nauerth
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
| | - David Ibberson
- Deep Sequencing Core Facility, CellNetworks Excellence Cluster, Heidelberg University, Im Neuenheimer Feld 267, D-69120 Heidelberg, Germany
| | - Rafael Martinez
- Centre for Organismal Studies Heidelberg, Department of Developmental Biology, Heidelberg University, Im Neuenheimer Feld 230, D-69120, Heidelberg, Germany
| | - Terezie M Mandakova
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Reinhard Zipper
- Institute of Biology, Plant Evolutionary Biology, University of Hohenheim, Garbenstrasse 30, D-70599 Stuttgart, Germany
| | - Anja Schmidt
- Centre for Organismal Studies Heidelberg, Department of Biodiversity and Plant Systematics, Heidelberg University, Im Neuenheimer Feld 345, D-69120 Heidelberg, Germany
- Institute of Biology, Plant Evolutionary Biology, University of Hohenheim, Garbenstrasse 30, D-70599 Stuttgart, Germany
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3
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Reifová R, Ament-Velásquez SL, Bourgeois Y, Coughlan J, Kulmuni J, Lipinska AP, Okude G, Stevison L, Yoshida K, Kitano J. Mechanisms of Intrinsic Postzygotic Isolation: From Traditional Genic and Chromosomal Views to Genomic and Epigenetic Perspectives. Cold Spring Harb Perspect Biol 2023; 15:a041607. [PMID: 37696577 PMCID: PMC10547394 DOI: 10.1101/cshperspect.a041607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
Intrinsic postzygotic isolation typically appears as reduced viability or fertility of interspecific hybrids caused by genetic incompatibilities between diverged parental genomes. Dobzhansky-Muller interactions among individual genes, and chromosomal rearrangements causing problems with chromosome synapsis and recombination in meiosis, have both long been considered as major mechanisms behind intrinsic postzygotic isolation. Recent research has, however, suggested that the genetic basis of intrinsic postzygotic isolation can be more complex and involves, for example, overall divergence of the DNA sequence or epigenetic changes. Here, we review the mechanisms of intrinsic postzygotic isolation from genic, chromosomal, genomic, and epigenetic perspectives across diverse taxa. We provide empirical evidence for these mechanisms, discuss their importance in the speciation process, and highlight questions that remain unanswered.
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Affiliation(s)
- Radka Reifová
- Department of Zoology, Faculty of Science, Charles University, 128 00 Prague, Czech Republic
| | | | - Yann Bourgeois
- DIADE, University of Montpellier, CIRAD, IRD, 34090 Montpellier, France
| | - Jenn Coughlan
- Department of Ecology & Evolutionary Biology, Yale University, New Haven, Connecticut 06520, USA
| | - Jonna Kulmuni
- Institute for Biodiversity and Ecosystem Dynamics, Department of Evolutionary and Population Biology, University of Amsterdam, 1012 Amsterdam, The Netherlands
- Organismal & Evolutionary Biology Research Programme, University of Helsinki, 00100 Helsinki, Finland
| | - Agnieszka P Lipinska
- Department of Algal Development and Evolution, Max Planck Institute for Biology, 72076 Tuebingen, Germany
- CNRS, UMR 8227, Integrative Biology of Marine Models, Sorbonne Université, Station Biologique de Roscoff, 29680 Roscoff, France
| | - Genta Okude
- Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Laurie Stevison
- Department of Biological Sciences, Auburn University, Auburn, Alabama 36849, USA
| | - Kohta Yoshida
- Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Jun Kitano
- Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
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Mao Y, Nakel T, Erbasol Serbes I, Joshi S, Tekleyohans DG, Baum T, Groß-Hardt R. ECS1 and ECS2 suppress polyspermy and the formation of haploid plants by promoting double fertilization. eLife 2023; 12:e85832. [PMID: 37489742 PMCID: PMC10421590 DOI: 10.7554/elife.85832] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 07/24/2023] [Indexed: 07/26/2023] Open
Abstract
The current pace of crop plant optimization is insufficient to meet future demands and there is an urgent need for novel breeding strategies. It was previously shown that plants tolerate the generation of triparental polyspermy-derived plants and that polyspermy can bypass hybridization barriers. Polyspermy thus has the potential to harness previously incompatible climate-adapted wild varieties for plant breeding. However, factors that influence polyspermy frequencies were not previously known. The endopeptidases ECS1 and ECS2 have been reported to prevent the attraction of supernumerary pollen tubes by cleaving the pollen tube attractant LURE1. Here, we show that these genes have an earlier function that is manifested by incomplete double fertilization in plants defective for both genes. In addition to supernumerary pollen tube attraction, ecs1 ecs2 mutants exhibit a delay in synergid disintegration, are susceptible to heterofertilization, and segregate haploid plants that lack a paternal genome contribution. Our results thus uncover ECS1 and ECS2 as the first female factors triggering the induction of maternal haploids. Capitalizing on a high-throughput polyspermy assay, we in addition show that the double mutant exhibits an increase in polyspermy frequencies. As both haploid induction and polyspermy are valuable breeding aims, our results open new avenues for accelerated generation of climate-adapted cultivars.
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Affiliation(s)
- Yanbo Mao
- University of Bremen, Centre for Biomolecular InteractionsBremenGermany
| | - Thomas Nakel
- University of Bremen, Centre for Biomolecular InteractionsBremenGermany
| | | | - Saurabh Joshi
- University of Bremen, Centre for Biomolecular InteractionsBremenGermany
| | | | - Thomas Baum
- University of Bremen, Centre for Biomolecular InteractionsBremenGermany
| | - Rita Groß-Hardt
- University of Bremen, Centre for Biomolecular InteractionsBremenGermany
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5
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He H, Shiragaki K, Tezuka T. Understanding and overcoming hybrid lethality in seed and seedling stages as barriers to hybridization and gene flow. FRONTIERS IN PLANT SCIENCE 2023; 14:1219417. [PMID: 37476165 PMCID: PMC10354522 DOI: 10.3389/fpls.2023.1219417] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 06/20/2023] [Indexed: 07/22/2023]
Abstract
Hybrid lethality is a type of reproductive isolation barrier observed in two developmental stages, hybrid embryos (hybrid seeds) and hybrid seedlings. Hybrid lethality has been reported in many plant species and limits distant hybridization breeding including interspecific and intergeneric hybridization, which increases genetic diversity and contributes to produce new germplasm for agricultural purposes. Recent studies have provided molecular and genetic evidence suggesting that underlying causes of hybrid lethality involve epistatic interaction of one or more loci, as hypothesized by the Bateson-Dobzhansky-Muller model, and effective ploidy or endosperm balance number. In this review, we focus on the similarities and differences between hybrid seed lethality and hybrid seedling lethality, as well as methods of recovering seed/seedling activity to circumvent hybrid lethality. Current knowledge summarized in our article will provides new insights into the mechanisms of hybrid lethality and effective methods for circumventing hybrid lethality.
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Affiliation(s)
- Hai He
- School of Agriculture, Sun Yat-sen University, Shenzhen, China
| | - Kumpei Shiragaki
- Laboratory of Plant Breeding and Genetics, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Takahiro Tezuka
- Laboratory of Breeding and Genetics, Graduate School of Agriculture, Osaka Metropolitan University, Sakai, Osaka, Japan
- Education and Research Field, School of Agriculture, Osaka Metropolitan University, Sakai, Osaka, Japan
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6
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Sugi N, Maruyama D. Exploring Novel Polytubey Reproduction Pathways Utilizing Cumulative Genetic Tools. PLANT & CELL PHYSIOLOGY 2023; 64:454-460. [PMID: 36943745 DOI: 10.1093/pcp/pcad021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/11/2023] [Accepted: 03/19/2023] [Indexed: 05/17/2023]
Abstract
In the anthers and ovaries of flowers, pollen grains and embryo sacs are produced with uniform cell compositions. This stable gametogenesis enables elaborate interactions between male and female gametophytes after pollination, forming the highly successful sexual reproduction system in flowering plants. As most ovules are fertilized with a single pollen tube, the resulting genome set in the embryo and endosperm is determined in a single pattern by independent fertilization of the egg cell and central cell by two sperm cells. However, if ovules receive four sperm cells from two pollen tubes, the expected options for genome sets in the developing seeds would more than double. In wild-type Arabidopsis thaliana plants, around 5% of ovules receive two pollen tubes. Recent studies have elucidated the abnormal fertilization in supernumerary pollen tubes and sperm cells related to polytubey, polyspermy, heterofertilization and fertilization recovery. Analyses of model plants have begun to uncover the mechanisms underlying this new pollen tube biology. Here, we review unusual fertilization phenomena and propose several breeding applications for flowering plants. These arguments contribute to the remodeling of plant reproduction, a challenging concept that alters typical plant fertilization by utilizing the current genetic toolbox.
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Affiliation(s)
- Naoya Sugi
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho, Totsuka-ku, Yokohama, Kanagawa, 244-0813 Japan
| | - Daisuke Maruyama
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho, Totsuka-ku, Yokohama, Kanagawa, 244-0813 Japan
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7
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Susaki D, Izumi R, Oi T, Takeuchi H, Shin JM, Sugi N, Kinoshita T, Higashiyama T, Kawashima T, Maruyama D. F-actin regulates the polarized secretion of pollen tube attractants in Arabidopsis synergid cells. THE PLANT CELL 2023; 35:1222-1240. [PMID: 36562145 PMCID: PMC10052382 DOI: 10.1093/plcell/koac371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
Pollen tube attraction is a key event of sexual reproduction in flowering plants. In the ovule, two synergid cells neighboring the egg cell control pollen tube arrival via the active secretion of attractant peptides such as AtLURE1 and XIUQIU from the filiform apparatus (FA) facing toward the micropyle. Distinctive cell polarity together with longitudinal F-actin and microtubules are hallmarks of the synergid cell in various species, though the functions of these cellular structures are unclear. In this study, we used genetic and pharmacological approaches to indicate the roles of cytoskeletal components in FA formation and pollen tube guidance in Arabidopsis thaliana. Genetic inhibition of microtubule formation reduced invaginations of the plasma membrane but did not abolish micropylar AtLURE1.2 accumulation. By contrast, the expression of a dominant-negative form of ACTIN8 induced disorganization of the FA and loss of polar AtLURE1.2 distribution toward the FA. Interestingly, after pollen tube reception, F-actin became unclear for a few hours in the persistent synergid cell, which may be involved in pausing and resuming pollen tube attraction during early polytubey block. Our data suggest that F-actin plays a central role in maintaining cell polarity and in mediating male-female communication in the synergid cell.
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Affiliation(s)
- Daichi Susaki
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho 641-12, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan
| | - Rie Izumi
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho 641-12, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan
| | - Takao Oi
- Graduate school of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Hidenori Takeuchi
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
- Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Ji Min Shin
- Department of Plant and Soil Sciences, University of Kentucky, 321 Plant Science Building, Lexington, Kentucky 40546, USA
| | - Naoya Sugi
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho 641-12, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho 641-12, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan
| | - Tetsuya Higashiyama
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tomokazu Kawashima
- Department of Plant and Soil Sciences, University of Kentucky, 321 Plant Science Building, Lexington, Kentucky 40546, USA
| | - Daisuke Maruyama
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho 641-12, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan
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Šemberová K, Svitok M, Marhold K, Suda J, Schmickl RE. Morphological and environmental differentiation as prezygotic reproductive barriers between parapatric and allopatric Campanula rotundifolia agg. cytotypes. ANNALS OF BOTANY 2023; 131:71-86. [PMID: 34559179 PMCID: PMC9904352 DOI: 10.1093/aob/mcab123] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 09/21/2021] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS Reproductive isolation and local establishment are necessary for plant speciation. Polyploidy, the possession of more than two complete chromosome sets, creates a strong postzygotic reproductive barrier between diploid and tetraploid cytotypes. However, this barrier weakens between polyploids (e.g. tetraploids and hexaploids). Reproductive isolation may be enhanced by cytotype morphological and environmental differentiation. Moreover, morphological adaptations to local conditions contribute to plant establishment. However, the relative contributions of ploidy level and the environment to morphology have generally been neglected. Thus, the extent of morphological variation driven by ploidy level and the environment was modelled for diploid, tetraploid and hexaploid cytotypes of Campanula rotundifolia agg. Cytotype distribution was updated, and morphological and environmental differentiation was tested in the presence and absence of natural contact zones. METHODS Cytotype distribution was assessed from 231 localities in Central Europe, including 48 localities with known chromosome counts, using flow cytometry. Differentiation in environmental niche and morphology was tested for cytotype pairs using discriminant analyses. A structural equation model was used to explore the synergies between cytotype, environment and morphology. KEY RESULTS Tremendous discrepancies were revealed between the reported and detected cytotype distribution. Neither mixed-ploidy populations nor interploidy hybrids were detected in the contact zones. Diploids had the broadest environmental niche, while hexaploids had the smallest and specialized niche. Hexaploids and spatially isolated cytotype pairs differed morphologically, including allopatric tetraploids. While leaf and shoot morphology were influenced by environmental conditions and polyploidy, flower morphology depended exclusively on the cytotype. CONCLUSIONS Reproductive isolation mechanisms vary between cytotypes. While diploids and polyploids are isolated postzygotically, the environmental niche shift is essential between higher polyploids. The impact of polyploidy and the environment on plant morphology implies the adaptive potential of polyploids, while the exclusive relationship between flower morphology and cytotype highlights the role of polyploidy in reproductive isolation.
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Affiliation(s)
| | - Marek Svitok
- Faculty of Ecology and Environmental Sciences, Technical University in Zvolen, T. G. Masaryka, Zvolen, Slovakia
- Faculty of Science, Department of Ecosystem Biology, University of South Bohemia, Branišovská, České Budějovice, Czech Republic
| | - Karol Marhold
- Faculty of Science, Department of Botany, Charles University, Benátská, Prague, Czech Republic
- Institute of Botany, Plant Science and Biodiversity Centre, Slovak Academy of Sciences, Dúbravská cesta, Bratislava, Slovakia
| | | | - Roswitha E Schmickl
- Faculty of Science, Department of Botany, Charles University, Benátská, Prague, Czech Republic
- Czech Academy of Sciences, Institute of Botany, Department of Evolutionary Plant Biology, Zámek, Průhonice, Czech Republic
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9
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Cheung AY, Duan Q, Li C, James Liu MC, Wu HM. Pollen-pistil interactions: It takes two to tangle but a molecular cast of many to deliver. CURRENT OPINION IN PLANT BIOLOGY 2022; 69:102279. [PMID: 36029655 DOI: 10.1016/j.pbi.2022.102279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 06/15/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Explosive advances have been made in the molecular understanding of pollen-pistil interactions that underlie reproductive success in flowering plants in the past three decades. Among the most notable is the discovery of pollen tube attractants [1∗,2∗]. The roles these molecules play in facilitating conspecific precedence thus promoting interspecific genetic isolation are also emerging [3-5]. Male-female interactions during the prezygotic phase and contributions from the male and female gametophytes have been comprehensively reviewed recently. Here, we focus on key advances in understanding the mechanistic underpinnings of how these interactions overcome barriers at various pollen-pistil interfaces along the pollen tube growth pathway to facilitate fertilization by desirable mates.
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Affiliation(s)
- Alice Y Cheung
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, USA; Molecular and Cell Biology Program, University of Massachusetts, Amherst, MA 01003, USA; Plant Biology Graduate Program, University of Massachusetts, Amherst, MA 01003, USA.
| | - Qiaohong Duan
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, Shandong, China; College of Horticultural Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, China
| | - Chao Li
- School of Life Sciences, East China Normal University, Shanghai, China
| | - Ming-Che James Liu
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, USA
| | - Hen-Ming Wu
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, USA; Molecular and Cell Biology Program, University of Massachusetts, Amherst, MA 01003, USA
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10
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Köhler C, Dziasek K, Del Toro-De León G. Postzygotic reproductive isolation established in the endosperm: mechanisms, drivers and relevance. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200118. [PMID: 33866810 DOI: 10.1098/rstb.2020.0118] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The endosperm is a developmental innovation of angiosperms that supports embryo growth and germination. Aside from this essential reproductive function, the endosperm fuels angiosperm evolution by rapidly establishing reproductive barriers between incipient species. Specifically, the endosperm prevents hybridization of newly formed polyploids with their non-polyploid progenitors, a phenomenon termed the triploid block. Furthermore, recently diverged diploid species are frequently reproductively isolated by endosperm-based hybridization barriers. Current genetic approaches have revealed a prominent role for epigenetic processes establishing these barriers. In particular, imprinted genes, which are expressed in a parent-of-origin-specific manner, underpin the interploidy barrier in the model species Arabidopsis. We will discuss the mechanisms establishing hybridization barriers in the endosperm, the driving forces for these barriers and their impact for angiosperm evolution. This article is part of the theme issue 'How does epigenetics influence the course of evolution?'
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Affiliation(s)
- Claudia Köhler
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Katarzyna Dziasek
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Gerardo Del Toro-De León
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
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11
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Nagahara S, Takeuchi H, Higashiyama T. Polyspermy Block in the Central Cell During Double Fertilization of Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2021; 11:588700. [PMID: 33510743 PMCID: PMC7835324 DOI: 10.3389/fpls.2020.588700] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 12/10/2020] [Indexed: 06/01/2023]
Abstract
During double fertilization in angiosperms, two male gametes (sperm cells), are released from a pollen tube into the receptive region between two female gametes; the egg cell and the central cell of the ovule. The sperm cells fertilize the egg cell and the central cell in a one-to-one manner to yield a zygote and an endosperm, respectively. The one-to-one distribution of the sperm cells to the two female gametes is strictly regulated, possibly via communication among the four gametes. Polyspermy block is the mechanism by which fertilized female gametes prevent fertilization by a secondary sperm cell, and has been suggested to operate in the egg cell rather than the central cell. However, whether the central cell also has the ability to avoid polyspermy during double fertilization remains unclear. Here, we assessed the one-to-one fertilization mechanism of the central cell by laser irradiation of the female gametes and live cell imaging of the fertilization process in Arabidopsis thaliana. We successfully disrupted an egg cell within the ovules by irradiation using a femtosecond pulse laser. In the egg-disrupted ovules, the central cell predominantly showed single fertilization by one sperm cell, suggesting that neither the egg cell nor its fusion with one sperm cell is necessary for one-to-one fertilization (i.e., monospermy) of the central cell. In addition, using tetraspore mutants possessing multiple sperm cell pairs in one pollen, we demonstrated that normal double fertilization was observed even when excess sperm cells were released into the receptive region between the female gametes. In ovules accepting four sperm cells, the egg cell never fused with more than one sperm cell, whereas half of the central cells fused with more than one sperm cell (i.e., polyspermy) even 1 h later. Our results suggest that the central cell can block polyspermy during double fertilization, although the central cell is more permissive to polyspermy than the egg cell. The potential contribution of polyspermy block by the central cell is discussed in terms of how it is involved in the one-to-one distribution of the sperm cells to two distinct female gametes.
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Affiliation(s)
- Shiori Nagahara
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Hidenori Takeuchi
- Institute of Transformative Bio-Molecules, Nagoya University, Nagoya, Japan
- Institute for Advanced Research, Nagoya University, Nagoya, Japan
| | - Tetsuya Higashiyama
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
- Institute of Transformative Bio-Molecules, Nagoya University, Nagoya, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
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Li HJ, Yang WC. Central Cell in Flowering Plants: Specification, Signaling, and Evolution. FRONTIERS IN PLANT SCIENCE 2020; 11:590307. [PMID: 33193544 PMCID: PMC7609669 DOI: 10.3389/fpls.2020.590307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 09/28/2020] [Indexed: 05/05/2023]
Abstract
During the reproduction of animals and lower plants, one sperm cell usually outcompetes the rivals to fertilize a single egg cell. But in flowering plants, two sperm cells fertilize the two adjacent dimorphic female gametes, the egg and central cell, respectively, to initiate the embryo and endosperm within a seed. The endosperm nourishes the embryo development and is also the major source of nutrition in cereals for humankind. Central cell as one of the key innovations of flowering plants is the biggest cell in the multicellular haploid female gametophyte (embryo sac). The embryo sac differentiates from the meiotic products through successive events of nuclear divisions, cellularization, and cell specification. Nowadays, accumulating lines of evidence are raveling multiple roles of the central cell rather than only the endosperm precursor. In this review, we summarize the current understanding on its cell fate specification, intercellular communication, and evolution. We also highlight some key unsolved questions for the further studies in this field.
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Affiliation(s)
- Hong-Ju Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Wei-Cai Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
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13
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Zeng RZ, Zhu J, Xu SY, Du GH, Guo HR, Chen J, Zhang ZS, Xie L. Unreduced Male Gamete Formation in Cymbidium and Its Use for Developing Sexual Polyploid Cultivars. FRONTIERS IN PLANT SCIENCE 2020; 11:558. [PMID: 32499802 PMCID: PMC7243674 DOI: 10.3389/fpls.2020.00558] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 04/14/2020] [Indexed: 05/05/2023]
Abstract
Polyploidy plays an important role in crop improvement. Polyploid plants, particularly those produced through unreduced gametes (2n gametes), show increased organ size, improved buffering capacity for deleterious mutations, and enhanced heterozygosity and heterosis. Induced polyploidy has been widely used for improving floriculture crops, however, there are few reported sexual polyploid plants in the floriculture industry. This study evaluated nine cultivars of Cymbidium Swartz and discovered that 2n male gametes occurred in this important orchid. Depending on cultivars, 2n male gamete formation frequencies varied from 0.15 to 4.03%. Interspecific hybrids generally produced more 2n male gametes than traditional cultivars. To generate sexual polyploid plants, seven pairs of crosses were made, which produced five triploid and two tetraploid hybrids. Two triploid hybrids were evaluated for in vitro regeneration and growth characteristics. Compared to the diploid parents, the triploids were more easily regenerated through rhizomes or protocorms, and regenerated plants had improved survival rates after transplanting to the greenhouse. Furthermore, the sexual polyploid plants had more compact growth style, produced fragrant flowers, and demonstrated heterosis in plant growth. Through this study, a reliable protocol for selection of appropriate parents for 2n gamete production, ploidy level evaluation, in vitro culture of polyploid progenies, and development of new polyploid cultivars was established. Our study with Cymbidium suggests that the use of 2n gametes is a viable approach for improving floriculture crops.
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Affiliation(s)
- Rui-Zhen Zeng
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| | - Jiao Zhu
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| | - Shi-Ying Xu
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Guo-Hui Du
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - He-Rong Guo
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| | - Jianjun Chen
- Environmental Horticulture Department, Mid-Florida Research and Education Center, Insititute of Food and Agrocultural Sciences (IFAS), University of Florida, Apopka, FL, United States
| | - Zhi-Sheng Zhang
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| | - Li Xie
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
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Hater F, Nakel T, Groß-Hardt R. Reproductive Multitasking: The Female Gametophyte. ANNUAL REVIEW OF PLANT BIOLOGY 2020; 71:517-546. [PMID: 32442389 DOI: 10.1146/annurev-arplant-081519-035943] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Fertilization of flowering plants requires the organization of complex tasks, many of which become integrated by the female gametophyte (FG). The FG is a few-celled haploid structure that orchestrates division of labor to coordinate successful interaction with the sperm cells and their transport vehicle, the pollen tube. As reproductive outcome is directly coupled to evolutionary success, the underlying mechanisms are under robust molecular control, including integrity check and repair mechanisms. Here, we review progress on understanding the development and function of the FG, starting with the functional megaspore, which represents the haploid founder cell of the FG. We highlight recent achievements that have greatly advanced our understanding of pollen tube attraction strategies and the mechanisms that regulate plant hybridization and gamete fusion. In addition, we discuss novel insights into plant polyploidization strategies that expand current concepts on the evolution of flowering plants.
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Affiliation(s)
- Friederike Hater
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
| | - Thomas Nakel
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
| | - Rita Groß-Hardt
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
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Abstract
Fertilization of an egg cell by more than one sperm cell can produce viable progeny in a flowering plant.
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Affiliation(s)
- Ajeet Chaudhary
- Plant Developmental Genetics, School of Life SciencesTechnical University of MunichFreisingGermany
| | - Rachele Tofanelli
- Plant Developmental Genetics, School of Life SciencesTechnical University of MunichFreisingGermany
| | - Kay Schneitz
- Plant Developmental Genetics, School of Life SciencesTechnical University of MunichFreisingGermany
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