1
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Florez-Rueda AM, Miguel CM, Figueiredo DD. Comparative transcriptomics of seed nourishing tissues: uncovering conserved and divergent pathways in seed plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 119:1134-1157. [PMID: 38709819 DOI: 10.1111/tpj.16786] [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: 10/13/2023] [Revised: 04/04/2024] [Accepted: 04/12/2024] [Indexed: 05/08/2024]
Abstract
The evolutionary and ecological success of spermatophytes is intrinsically linked to the seed habit, which provides a protective environment for the initial development of the new generation. This environment includes an ephemeral nourishing tissue that supports embryo growth. In gymnosperms this tissue originates from the asexual proliferation of the maternal megagametophyte, while in angiosperms it is a product of fertilization, and is called the endosperm. The emergence of these nourishing tissues is of profound evolutionary value, and they are also food staples for most of the world's population. Here, using Orthofinder to infer orthologue genes among newly generated and previously published datasets, we provide a comparative transcriptomic analysis of seed nourishing tissues from species of several angiosperm clades, including those of early diverging lineages, as well as of one gymnosperm. Our results show that, although the structure and composition of seed nourishing tissues has seen significant divergence along evolution, there are signatures that are conserved throughout the phylogeny. Conversely, we identified processes that are specific to species within the clades studied, and thus illustrate their functional divergence. With this, we aimed to provide a foundation for future studies on the evolutionary history of seed nourishing structures, as well as a resource for gene discovery in future functional studies.
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Affiliation(s)
- Ana Marcela Florez-Rueda
- Max Planck Institute of Molecular Plant Physiology, Potsdam Science Park, Am Mühlenberg 1, 14476, Potsdam, Germany
- University of Potsdam, Karl-Liebknechts-Str. 24-25, Haus 26, 14476, Potsdam, Germany
| | - Célia M Miguel
- Faculty of Sciences, Biosystems and Integrative Sciences Institute (BioISI), University of Lisbon, Lisboa, Portugal
| | - Duarte D Figueiredo
- Max Planck Institute of Molecular Plant Physiology, Potsdam Science Park, Am Mühlenberg 1, 14476, Potsdam, Germany
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2
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Khouider S, Gehring M. Parental dialectic: Epigenetic conversations in endosperm. CURRENT OPINION IN PLANT BIOLOGY 2024; 81:102591. [PMID: 38944896 DOI: 10.1016/j.pbi.2024.102591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/21/2024] [Accepted: 06/07/2024] [Indexed: 07/02/2024]
Abstract
Endosperm is a major evolutionary innovation of flowering plants, and its proper development critically impacts seed growth and viability. Epigenetic regulators have a key function in parental control of endosperm development. Notably, epigenetic regulation of parental genome dosage is a major determinant of seed development success, and disruption of this balance can produce inviable seed, as observed in some interploidy and interspecific crosses. These postzygotic reproduction barriers are also a potent driver of speciation. The molecular machinery and regulatory architecture governing endosperm development is proposed to have evolved under parental conflict. In this review, we emphasize parental conflict as a dialectic conflict and discuss recent findings about the epigenetic molecular machinery that mediates parental conflict in the endosperm.
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Affiliation(s)
- Souraya Khouider
- Whitehead Institute for Biomedical Research, Cambridge MA 02142, USA
| | - Mary Gehring
- Whitehead Institute for Biomedical Research, Cambridge MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139, USA.
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3
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Soliman HK, Coughlan JM. United by Conflict: Convergent Signatures of Parental Conflict in Angiosperms and Placental Mammals. J Hered 2024:esae009. [PMID: 38366852 DOI: 10.1093/jhered/esae009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Indexed: 02/18/2024] Open
Abstract
Endosperm in angiosperms and placenta in eutherians are convergent innovations for efficient embryonic nutrient transfer. Despite advantages, this reproductive strategy incurs metabolic costs that maternal parents disproportionately shoulder, leading to potential inter-parental conflict over optimal offspring investment. Genomic imprinting-parent-of-origin-biased gene expression-is fundamental for endosperm and placenta development and has convergently evolved in angiosperms and mammals, in part, to resolve parental conflict. Here, we review the mechanisms of genomic imprinting in these taxa. Despite differences in the timing and spatial extent of imprinting, these taxa exhibit remarkable convergence in the molecular machinery and genes governing imprinting. We then assess the role of parental conflict in shaping evolution within angiosperms and eutherians using four criteria: (1) Do differences in the extent of sibling relatedness cause differences in the inferred strength of parental conflict? (2) Do reciprocal crosses between taxa with different inferred histories of parental conflict exhibit parent-of-origin growth effects? (3) Are these parent-of-origin growth effects caused by dosage-sensitive mechanisms and do these loci exhibit signals of positive selection? (4) Can normal development be restored by genomic perturbations that restore stoichiometric balance in the endosperm/placenta? Although we find evidence for all criteria in angiosperms and eutherians, suggesting that parental conflict may help shape their evolution, many questions remain. Additionally, myriad differences between the two taxa suggest that their respective biologies may shape how/when/where/to what extent parental conflict manifests. Lastly, we discuss outstanding questions, highlighting the power of comparative work in quantifying the role of parental conflict in evolution.
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Affiliation(s)
- Hagar K Soliman
- Department of Ecology & Evolutionary Biology, Yale University, New Haven, CT, 06511, United States
- Department of Biotechnology, Faculty of Science, Cairo University, Giza, 12613, Egypt
| | - Jenn M Coughlan
- Department of Ecology & Evolutionary Biology, Yale University, New Haven, CT, 06511, United States
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4
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Tezuka T, Nagai S, Matsuo C, Okamori T, Iizuka T, Marubashi W. Genetic Cause of Hybrid Lethality Observed in Reciprocal Interspecific Crosses between Nicotiana simulans and N. tabacum. Int J Mol Sci 2024; 25:1226. [PMID: 38279225 PMCID: PMC10817076 DOI: 10.3390/ijms25021226] [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: 12/22/2023] [Revised: 01/17/2024] [Accepted: 01/17/2024] [Indexed: 01/28/2024] Open
Abstract
Hybrid lethality, a type of postzygotic reproductive isolation, is an obstacle to wide hybridization breeding. Here, we report the hybrid lethality that was observed in crosses between the cultivated tobacco, Nicotiana tabacum (section Nicotiana), and the wild tobacco species, Nicotiana simulans (section Suaveolentes). Reciprocal hybrid seedlings were inviable at 28 °C, and the lethality was characterized by browning of the hypocotyl and roots, suggesting that hybrid lethality is due to the interaction of nuclear genomes derived from each parental species, and not to a cytoplasmic effect. Hybrid lethality was temperature-sensitive and suppressed at 36 °C. However, when hybrid seedlings cultured at 36 °C were transferred to 28 °C, all of them showed hybrid lethality. After crossing between an N. tabacum monosomic line missing one copy of the Q chromosome and N. simulans, hybrid seedlings with or without the Q chromosome were inviable and viable, respectively. These results indicated that gene(s) on the Q chromosome are responsible for hybrid lethality and also suggested that N. simulans has the same allele at the Hybrid Lethality A1 (HLA1) locus responsible for hybrid lethality as other species in the section Suaveolentes. Haplotype analysis around the HLA1 locus suggested that there are at least six and two haplotypes containing Hla1-1 and hla1-2 alleles, respectively, in the section Suaveolentes.
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Affiliation(s)
- Takahiro Tezuka
- Graduate School of Agriculture, Osaka Metropolitan University, Sakai 599-8531, Osaka, Japan;
- Education and Research Field, School of Agriculture, Osaka Metropolitan University, Sakai 599-8531, Osaka, Japan
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531, Osaka, Japan;
- School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531, Osaka, Japan
| | - Shota Nagai
- Graduate School of Agriculture, Osaka Metropolitan University, Sakai 599-8531, Osaka, Japan;
| | - Chihiro Matsuo
- School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531, Osaka, Japan
| | - Toshiaki Okamori
- School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531, Osaka, Japan
| | - Takahiro Iizuka
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531, Osaka, Japan;
| | - Wataru Marubashi
- School of Agriculture, Meiji University, Kawasaki 214-8571, Kanagawa, Japan;
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5
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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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6
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Behling WL, Douches DS. The Effect of Self-Compatibility Factors on Interspecific Compatibility in Solanum Section Petota. PLANTS (BASEL, SWITZERLAND) 2023; 12:1709. [PMID: 37111931 PMCID: PMC10144722 DOI: 10.3390/plants12081709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/14/2023] [Accepted: 04/18/2023] [Indexed: 06/19/2023]
Abstract
The relationships of interspecific compatibility and incompatibility in Solanum section Petota are complex. Inquiry into these relationships in tomato and its wild relatives has elucidated the pleiotropic and redundant function of S-RNase and HT which tandemly and independently mediate both interspecific and intraspecific pollen rejection. Our findings presented here are consistent with previous work conducted in Solanum section Lycopersicon showing that S-RNase plays a central role in interspecific pollen rejection. Statistical analyses also demonstrated that HT-B alone is not a significant factor in these pollinations; demonstrating the overlap in gene function between HT-A and HT-B, as HT-A, was present and functional in all genotypes used. We were not able to replicate the general absence of prezygotic stylar barriers observable in S. verrucosum, which has been attributed to the lack of S-RNase, indicating that other non-S-RNase factors play a significant role. We also demonstrated that Sli played no significant role in these interspecific pollinations, directly conflicting with previous research. It is possible that S. chacoense as a pollen donor is better able to bypass stylar barriers in 1EBN species such as S. pinnatisectum. Consequently, S. chacoense may be a valuable resource in accessing these 1EBN species regardless of Sli status.
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7
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Coughlan JM. The role of hybrid seed inviability in angiosperm speciation. AMERICAN JOURNAL OF BOTANY 2023; 110:1-14. [PMID: 36801827 DOI: 10.1002/ajb2.16135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 01/05/2023] [Accepted: 01/05/2023] [Indexed: 05/11/2023]
Abstract
Understanding which reproductive barriers contribute to speciation is essential to understanding the diversity of life on earth. Several contemporary examples of strong hybrid seed inviability (HSI) between recently diverged species suggest that HSI may play a fundamental role in plant speciation. Yet, a broader synthesis of HSI is needed to clarify its role in diversification. Here, I review the incidence and evolution of HSI. Hybrid seed inviability is common and evolves rapidly, suggesting that it may play an important role early in speciation. The developmental mechanisms that underlie HSI involve similar developmental trajectories in endosperm, even between evolutionarily deeply diverged incidents of HSI. In hybrid endosperm, HSI is often accompanied by whole-scale gene misexpression, including misexpression of imprinted genes which have a key role in endosperm development. I explore how an evolutionary perspective can clarify the repeated and rapid evolution of HSI. In particular, I evaluate the evidence for conflict between maternal and paternal interests in resource allocation to offspring (i.e., parental conflict). I highlight that parental conflict theory generates explicit predictions regarding the expected hybrid phenotypes and genes responsible for HSI. While much phenotypic evidence supports a role of parental conflict in the evolution of HSI, an understanding of the underlying molecular mechanisms of this barrier is essential to test parental conflict theory. Lastly, I explore what factors may influence the strength of parental conflict in natural plant populations as an explanation for why rates of HSI may differ between plant groups and the consequences of strong HSI in secondary contact.
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Affiliation(s)
- Jenn M Coughlan
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, 06511, USA
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8
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Xu W, Sato H, Bente H, Santos-González J, Köhler C. Endosperm cellularization failure induces a dehydration-stress response leading to embryo arrest. THE PLANT CELL 2023; 35:874-888. [PMID: 36427255 PMCID: PMC9940880 DOI: 10.1093/plcell/koac337] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 11/22/2022] [Indexed: 06/16/2023]
Abstract
The endosperm is a nutritive tissue supporting embryo growth in flowering plants. Most commonly, the endosperm initially develops as a coenocyte (multinucleate cell) and then cellularizes. This process of cellularization is frequently disrupted in hybrid seeds generated by crosses between different flowering plant species or plants that differ in ploidy, resulting in embryo arrest and seed lethality. The reason for embryo arrest upon cellularization failure remains unclear. In this study, we show that triploid Arabidopsis thaliana embryos surrounded by uncellularized endosperm mount an osmotic stress response that is connected to increased levels of abscisic acid (ABA) and enhanced ABA responses. Impairing ABA biosynthesis and signaling aggravated triploid seed abortion, while increasing endogenous ABA levels as well as the exogenous application of ABA-induced endosperm cellularization and suppressed embryo growth arrest. Taking these results together, we propose that endosperm cellularization is required to establish dehydration tolerance in the developing embryo, ensuring its survival during seed maturation.
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Affiliation(s)
- Wenjia Xu
- Swedish University of Agricultural Sciences & Linnean Center for Plant Biology, Uppsala BioCenter, Almas Allé 5, SE-750 07 Uppsala, Sweden
| | - Hikaru Sato
- Swedish University of Agricultural Sciences & Linnean Center for Plant Biology, Uppsala BioCenter, Almas Allé 5, SE-750 07 Uppsala, Sweden
| | - Heinrich Bente
- Swedish University of Agricultural Sciences & Linnean Center for Plant Biology, Uppsala BioCenter, Almas Allé 5, SE-750 07 Uppsala, Sweden
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Juan Santos-González
- Swedish University of Agricultural Sciences & Linnean Center for Plant Biology, Uppsala BioCenter, Almas Allé 5, SE-750 07 Uppsala, Sweden
| | - Claudia Köhler
- Swedish University of Agricultural Sciences & Linnean Center for Plant Biology, Uppsala BioCenter, Almas Allé 5, SE-750 07 Uppsala, Sweden
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
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9
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Coughlan JM. Indirect Effects of Parental Conflict on Conspecific Offspring Development. Am Nat 2023; 201:154-162. [PMID: 36524928 DOI: 10.1086/721919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractHybrid seed inviability is a common reproductive barrier in angiosperms. Recent work suggests that the rapid evolution of hybrid seed inviability may, in part, be due to conflict between maternal and paternal optima for resource allocation to developing offspring (i.e., parental conflict). However, parental conflict requires that paternally derived resource-acquiring alleles impose a maternal cost. I test this requirement using three closely related species in the Mimulus guttatus species complex that exhibit significant hybrid seed inviability and differ in their inferred histories of parental conflict. I show that the presence of hybrid seeds significantly affects conspecific seed size for almost all crosses, such that conspecific seeds are smaller after developing with hybrids sired by fathers with a stronger history of conflict and are larger after developing with hybrids sired by fathers with a weaker history of conflict. This work demonstrates a potential maternal cost of paternally derived alleles and also has implications for species fitness in secondary contact.
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10
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Abstract
Introducing asexual reproduction through seeds - apomixis - into crop species could revolutionize agriculture by allowing F1 hybrids with enhanced yield and stability to be clonally propagated. Engineering synthetic apomixis has proven feasible in inbred rice through the inactivation of three genes (MiMe), which results in the conversion of meiosis into mitosis in a line ectopically expressing the BABYBOOM1 (BBM1) parthenogenetic trigger in egg cells. However, only 10-30% of the seeds are clonal. Here, we show that synthetic apomixis can be achieved in an F1 hybrid of rice by inducing MiMe mutations and egg cell expression of BBM1 in a single step. We generate hybrid plants that produce more than 95% of clonal seeds across multiple generations. Clonal apomictic plants maintain the phenotype of the F1 hybrid along successive generations. Our results demonstrate that there is no barrier to almost fully penetrant synthetic apomixis in an important crop species, rendering it compatible with use in agriculture.
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11
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Roy AK, Chakraborti M, Radhakrishna A, Dwivedi KK, Srivastava MK, Saxena S, Paul S, Khare A, Malaviya DR, Kaushal P. Alien genome mobilization and fixation utilizing an apomixis mediated genome addition (AMGA) strategy in Pennisetum to improve domestication traits of P. squamulatum. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2022; 135:2555-2575. [PMID: 35726065 DOI: 10.1007/s00122-022-04138-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 05/23/2022] [Indexed: 06/15/2023]
Abstract
An approach to release 'frozen' variability in apomictic species using sexuality of another species, eventually its utilization in crop improvement and de-novo domestication of crop wild relatives is presented. Pennisetum squamulatum, a secondary gene pool species of pearl millet (P. glaucum), harbours many desirable traits. However, it was neither utilized to improve pearl millet fodder traits nor improvement of its own domestication traits was attempted, due to the complexities of genomes and apomictic reproduction. To overcome this, we followed an Apomixis Mediated Genome Addition (AMGA) strategy and utilized the contrasting reproductive capacities (sexuality and apomixis) of both the species to access the otherwise un-available variability embedded in P. squamulatum. Segregating population of interspecific hybrids exhibited significant variability and heterosis for desired morphological, agronomical, and nutritional traits. Elite apomictic and perennial hybrids were evaluated in breeding trials, and eventually a novel grass cultivar was released for commercial cultivation in India. The performance of newly developed cultivar was superior to other adapted perennial grasses of arid and semi-arid rangelands. Through AMGA, the sexuality of one species was successfully utilized to 'release' the 'frozen' variability embedded in another species. Subsequently, the hybrids representing desirable trait combinations were again 'fixed' utilizing the apomixis alleles from the male parent in a back-and-forth apomixis-sexual-apomixis selection cycle. This study also demonstrated the potential of AMGA to improve crop relatives through genomes introgression as well as de novo domestication of new crops from wild species.
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Affiliation(s)
- A K Roy
- ICAR - Indian Grassland and Fodder Research Institute, Jhansi, 284003, India
| | - M Chakraborti
- ICAR - National Rice Research Institute, Cuttack, 753006, India
| | - A Radhakrishna
- ICAR - Indian Grassland and Fodder Research Institute, Jhansi, 284003, India
| | - K K Dwivedi
- ICAR - Indian Grassland and Fodder Research Institute, Jhansi, 284003, India
| | - M K Srivastava
- ICAR - Indian Institute of Soybean Research, Indore, 452001, India
| | - S Saxena
- ICAR - Indian Grassland and Fodder Research Institute, Jhansi, 284003, India
| | - S Paul
- ICAR - Indian Grassland and Fodder Research Institute, Jhansi, 284003, India
| | - Aarti Khare
- ICAR - Indian Grassland and Fodder Research Institute, Jhansi, 284003, India
| | - D R Malaviya
- ICAR - Indian Institute of Sugarcane Research, Lucknow, 226002, India
| | - P Kaushal
- ICAR - National Institute of Biotic Stress Management, Raipur, 493225, India.
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12
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Underwood CJ, Mercier R. Engineering Apomixis: Clonal Seeds Approaching the Fields. ANNUAL REVIEW OF PLANT BIOLOGY 2022; 73:201-225. [PMID: 35138881 DOI: 10.1146/annurev-arplant-102720-013958] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Apomixis is a form of reproduction leading to clonal seeds and offspring that are genetically identical to the maternal plant. While apomixis naturally occurs in hundreds of plant species distributed across diverse plant families, it is absent in major crop species. Apomixis has a revolutionary potential in plant breeding, as it could allow the instant fixation and propagation though seeds of any plant genotype, most notably F1 hybrids. Mastering and implementing apomixis would reduce the cost of hybrid seed production, facilitate new types of hybrid breeding, and make it possible to harness hybrid vigor in crops that are not presently cultivated as hybrids. Synthetic apomixis can be engineered by combining modifications of meiosis and fertilization. Here, we review the current knowledge and recent major achievements toward the development of efficient apomictic systems usable in agriculture.
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Affiliation(s)
- Charles J Underwood
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany; ,
| | - Raphael Mercier
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany; ,
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13
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He H, Sadahisa K, Yokoi S, Tezuka T. Parental Genome Imbalance Causes Hybrid Seed Lethality as Well as Ovary Abscission in Interspecific and Interploidy Crosses in Nicotiana. FRONTIERS IN PLANT SCIENCE 2022; 13:899206. [PMID: 35665169 PMCID: PMC9161172 DOI: 10.3389/fpls.2022.899206] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
Enhanced ovary abscission after pollination and hybrid seed lethality result in post-zygotic reproductive isolation in plant interspecific crosses. However, the connection between these barriers remains unclear. Here, we report that an imbalance in parental genomes or endosperm balance number (EBN) causes hybrid seed lethality and ovary abscission in both interspecific and intraspecific-interploidy crosses in the genus Nicotiana. Auxin treatment suppressed ovary abscission, but not hybrid seed lethality, in an interspecific cross between Nicotiana suaveolens and N. tabacum, suggesting that ovary abscission-related genes are located downstream of those involved in hybrid seed lethality. We performed interploidy crosses among N. suaveolens tetraploids, octoploids, and neopolyploids and revealed hybrid seed lethality and ovary abscission in interploid crosses. Furthermore, a higher maternal EBN than paternal EBN caused these barriers, as previously observed in N. suaveolens × N. tabacum crosses. Altogether, these results suggest that maternal excess of EBN causes hybrid seed lethality, which in turn leads to ovary abscission through the same mechanism in both interspecific and interploidy crosses.
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Affiliation(s)
- Hai He
- Laboratory of Plant Breeding and Propagation, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Kumi Sadahisa
- Laboratory of Plant Breeding and Propagation, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Shuji Yokoi
- Laboratory of Plant Breeding and Propagation, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
- Laboratory of Breeding and Genetics, Graduate School of Agriculture, Osaka Metropolitan University, Sakai, Japan
- Education and Research Field, School of Agriculture, Osaka Metropolitan University, Sakai, Japan
- Bioeconomy Research Institute, Research Center for the 21st Century, Osaka Metropolitan University, Sakai, Japan
| | - Takahiro Tezuka
- Laboratory of Plant Breeding and Propagation, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
- Laboratory of Breeding and Genetics, Graduate School of Agriculture, Osaka Metropolitan University, Sakai, Japan
- Education and Research Field, School of Agriculture, Osaka Metropolitan University, Sakai, Japan
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14
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Castillo-Bravo R, Fort A, Cashell R, Brychkova G, McKeown PC, Spillane C. Parent-of-Origin Effects on Seed Size Modify Heterosis Responses in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2022; 13:835219. [PMID: 35330872 PMCID: PMC8940307 DOI: 10.3389/fpls.2022.835219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 01/19/2022] [Indexed: 05/05/2023]
Abstract
Parent-of-origin effects arise when a phenotype depends on whether it is inherited maternally or paternally. Parent-of-origin effects can exert a strong influence on F1 seed size in flowering plants, an important agronomic and life-history trait that can contribute to biomass heterosis. Here we investigate the natural variation in the relative contributions of the maternal and paternal genomes to F1 seed size across 71 reciprocal pairs of F1 hybrid diploids and the parental effect on F1 seed size heterosis. We demonstrate that the paternally derived genome influences F1 seed size more significantly than previously appreciated. We further demonstrate (by disruption of parental genome dosage balance in F1 triploid seeds) that hybridity acts as an enhancer of genome dosage effects on F1 seed size, beyond that observed from hybridity or genome dosage effects on their own. Our findings indicate that interactions between genetic hybridity and parental genome dosage can enhance heterosis effects in plants, opening new avenues for boosting heterosis breeding in crop plants.
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15
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Huc J, Dziasek K, Pachamuthu K, Woh T, Köhler C, Borges F. Bypassing reproductive barriers in hybrid seeds using chemically induced epimutagenesis. THE PLANT CELL 2022; 34:989-1001. [PMID: 34792584 PMCID: PMC8894923 DOI: 10.1093/plcell/koab284] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 11/09/2021] [Indexed: 05/13/2023]
Abstract
The triploid block, which prevents interploidy hybridizations in flowering plants, is characterized by a failure in endosperm development, arrest in embryogenesis, and seed collapse. Many genetic components of triploid seed lethality have been successfully identified in the model plant Arabidopsis thaliana, most notably the paternally expressed genes (PEGs), which are upregulated in tetraploid endosperm with paternal excess. Previous studies have shown that the paternal epigenome is a key determinant of the triploid block response, as the loss of DNA methylation in diploid pollen suppresses the triploid block almost completely. Here, we demonstrate that triploid seed collapse is bypassed in Arabidopsis plants treated with the DNA methyltransferase inhibitor 5-Azacytidine during seed germination and early growth. We identified strong suppressor lines showing stable transgenerational inheritance of hypomethylation in the CG context, as well as normalized expression of PEGs in triploid seeds. Importantly, differentially methylated loci segregate in the progeny of "epimutagenized" plants, which may allow epialleles involved in the triploid block response to be identified in future studies. Finally, we demonstrate that chemically induced epimutagenesis facilitates hybridization between different Capsella species, thus potentially emerging as a strategy for producing triploids and interspecific hybrids with high agronomic interest.
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Affiliation(s)
- Jonathan Huc
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Katarzyna Dziasek
- Department of Plant Biology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Linnean Center of Plant Biology, Uppsala, Sweden
| | - Kannan Pachamuthu
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Tristan Woh
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Claudia Köhler
- Department of Plant Biology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Linnean Center of Plant Biology, Uppsala, Sweden
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Filipe Borges
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
- Author for correspondence:
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Bischof S. Bypassing reproductive barriers by chemical epimutagenesis. THE PLANT CELL 2022; 34:947-948. [PMID: 35243510 PMCID: PMC8894918 DOI: 10.1093/plcell/koab314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Affiliation(s)
- Sylvain Bischof
- Assistant Features Editor, The Plant Cell,
American Society of Plant Biologists, USA
- Department of Plant and Microbial Biology, University of Zürich,
8006 Zürich, Switzerland
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Hörandl E. Novel Approaches for Species Concepts and Delimitation in Polyploids and Hybrids. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11020204. [PMID: 35050093 PMCID: PMC8781807 DOI: 10.3390/plants11020204] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 01/07/2022] [Accepted: 01/10/2022] [Indexed: 05/08/2023]
Abstract
Hybridization and polyploidization are important processes for plant evolution. However, classification of hybrid or polyploid species has been notoriously difficult because of the complexity of processes and different evolutionary scenarios that do not fit with classical species concepts. Polyploid complexes are formed via combinations of allopolyploidy, autopolyploidy and homoploid hybridization with persisting sexual reproduction, resulting in many discrete lineages that have been classified as species. Polyploid complexes with facultative apomixis result in complicated net-work like clusters, or rarely in agamospecies. Various case studies illustrate the problems that apply to traditional species concepts to hybrids and polyploids. Conceptual progress can be made if lineage formation is accepted as an inevitable consequence of meiotic sex, which is established already in the first eukaryotes as a DNA restoration tool. The turnaround of the viewpoint that sex forms species as lineages helps to overcome traditional thinking of species as "units". Lineage formation and self-sustainability is the prerequisite for speciation and can also be applied to hybrids and polyploids. Species delimitation is aided by the improved recognition of lineages via various novel -omics methods, by understanding meiosis functions, and by recognizing functional phenotypes by considering morphological-physiological-ecological adaptations.
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Affiliation(s)
- Elvira Hörandl
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), University of Goettingen, 37073 Göttingen, Germany
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Qiu Y, Köhler C. Endosperm Evolution by Duplicated and Neofunctionalized Type I MADS-Box Transcription Factors. Mol Biol Evol 2022; 39:msab355. [PMID: 34897514 PMCID: PMC8788222 DOI: 10.1093/molbev/msab355] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
MADS-box transcription factors (TFs) are present in nearly all major eukaryotic groups. They are divided into Type I and Type II that differ in domain structure, functional roles, and rates of evolution. In flowering plants, major evolutionary innovations like flowers, ovules, and fruits have been closely connected to Type II MADS-box TFs. The role of Type I MADS-box TFs in angiosperm evolution remains to be identified. Here, we show that the formation of angiosperm-specific Type I MADS-box clades of Mγ and Mγ-interacting Mα genes (Mα*) can be tracked back to the ancestor of all angiosperms. Angiosperm-specific Mγ and Mα* genes were preferentially expressed in the endosperm, consistent with their proposed function as heterodimers in the angiosperm-specific embryo nourishing endosperm tissue. We propose that duplication and diversification of Type I MADS genes underpin the evolution of the endosperm, a developmental innovation closely connected to the origin and success of angiosperms.
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Affiliation(s)
- Yichun Qiu
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Centre for Plant Biology, Uppsala, Sweden
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Claudia Köhler
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Centre for Plant Biology, Uppsala, Sweden
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
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Ashe A, Colot V, Oldroyd BP. How does epigenetics influence the course of evolution? Philos Trans R Soc Lond B Biol Sci 2021; 376:20200111. [PMID: 33866814 PMCID: PMC8059608 DOI: 10.1098/rstb.2020.0111] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2021] [Indexed: 12/11/2022] Open
Abstract
Epigenetics is the study of changes in gene activity that can be transmitted through cell divisions but cannot be explained by changes in the DNA sequence. Epigenetic mechanisms are central to gene regulation, phenotypic plasticity, development and the preservation of genome integrity. Epigenetic mechanisms are often held to make a minor contribution to evolutionary change because epigenetic states are typically erased and reset at every generation, and are therefore, not heritable. Nonetheless, there is growing appreciation that epigenetic variation makes direct and indirect contributions to evolutionary processes. First, some epigenetic states are transmitted intergenerationally and affect the phenotype of offspring. Moreover, bona fide heritable 'epialleles' exist and are quite common in plants. Such epialleles could, therefore, be subject to natural selection in the same way as conventional DNA sequence-based alleles. Second, epigenetic variation enhances phenotypic plasticity and phenotypic variance and thus can modulate the effect of natural selection on sequence-based genetic variation. Third, given that phenotypic plasticity is central to the adaptability of organisms, epigenetic mechanisms that generate plasticity and acclimation are important to consider in evolutionary theory. Fourth, some genes are under selection to be 'imprinted' identifying the sex of the parent from which they were derived, leading to parent-of-origin-dependent gene expression and effects. These effects can generate hybrid disfunction and contribute to speciation. Finally, epigenetic processes, particularly DNA methylation, contribute directly to DNA sequence evolution, because they act as mutagens on the one hand and modulate genome stability on the other by keeping transposable elements in check. This article is part of the theme issue 'How does epigenetics influence the course of evolution?'
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Affiliation(s)
- Alyson Ashe
- School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Vincent Colot
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Ecole Normale Supérieure, PSL Research University, 75005 Paris, France
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