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Wang T, van Dijk ADJ, Zhao R, Bonnema G, Wang X. Contribution of homoeologous exchange to domestication of polyploid Brassica. Genome Biol 2024; 25:231. [PMID: 39192349 DOI: 10.1186/s13059-024-03370-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Accepted: 08/10/2024] [Indexed: 08/29/2024] Open
Abstract
BACKGROUND Polyploidy is widely recognized as a significant evolutionary force in the plant kingdom, contributing to the diversification of plants. One of the notable features of allopolyploidy is the occurrence of homoeologous exchange (HE) events between the subgenomes, causing changes in genomic composition, gene expression, and phenotypic variations. However, the role of HE in plant adaptation and domestication remains unclear. RESULTS Here we analyze the whole-genome resequencing data from Brassica napus accessions representing the different morphotypes and ecotypes, to investigate the role of HE in domestication. Our findings demonstrate frequent occurrence of HEs in Brassica napus, with substantial HE patterns shared across populations, indicating their potential role in promoting crop domestication. HE events are asymmetric, with the A genome more frequently replacing C genome segments. These events show a preference for specific genomic regions and vary among populations. We also identify candidate genes in HE regions specific to certain populations, which likely contribute to flowering-time diversification across diverse morphotypes and ecotypes. In addition, we assemble a new genome of a swede accession, confirming the HE signals on the genome and their potential involvement in root tuber development. By analyzing HE in another allopolyploid species, Brassica juncea, we characterize a potential broader role of HE in allopolyploid crop domestication. CONCLUSIONS Our results provide novel insights into the domestication of polyploid Brassica species and highlight homoeologous exchange as a crucial mechanism for generating variations that are selected for crop improvement in polyploid species.
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Affiliation(s)
- Tianpeng Wang
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
- Plant Breeding, Wageningen University and Research, Wageningen, The Netherlands
- Bioinformatics Group, Wageningen University and Research, Wageningen, The Netherlands
| | - Aalt D J van Dijk
- Bioinformatics Group, Wageningen University and Research, Wageningen, The Netherlands
| | - Ranze Zhao
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Guusje Bonnema
- Plant Breeding, Wageningen University and Research, Wageningen, The Netherlands.
| | - Xiaowu Wang
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China.
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Shinke T, Yamazaki A, Nakamura S, Kudoh H, Hosokawa M. Genetic diversification of allohexaploid Brassica hybrids (AABBCC) using a fertile octoploid with excessive C genome set (AABBCCCC). PLANTA 2024; 260:71. [PMID: 39136783 DOI: 10.1007/s00425-024-04497-w] [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: 06/13/2024] [Accepted: 07/29/2024] [Indexed: 08/29/2024]
Abstract
MAIN CONCLUSION Using octoploid somatic hybrids with excessive C genome sets, AABBCCCC, a diverse allohexaploid, AABBCC, was produced by C genome reduction through subsequent crossing with various AABB cultivars. Even when somatic hybrids are produced, the plants that are produced are rarely in themselves an innovative crop. In this study, we used somatic hybrids of Brassica juncea (AABB) and B. oleracea (CC) as model cases for the genetic diversification of the somatic hybrids. One cell of 'Akaoba Takana' (B. juncea) and two cells of 'Snow Crown' (B. oleracea) were fused to create several somatic hybrids with excessive C genomes, AABBCCCC. Using AABBCCCC somatic hybrids as mother plants and crossing with 'Akaoba Takana', the AABBCC progenies were generated. When these AABBCC plants were self-fertilized, and flow cytometric (FCM) analysis was performed on the next generations, differences in the relative amount of genome size variation were observed, depending on the different AABBCCCC parents used for AABBCC creation. Further self-progeny was obtained for AABBCC plants with a theoretical allohexaploid DNA index by FCM. However, as the DNA indices of the progeny populations varied between plants used and aneuploid individuals still occurred in the progeny populations, it was difficult to say that the allohexaploid genome was fully stabilized. Next, to obtain genetic diversification of the allohexaploid, different cultivars of B. juncea were crossed with AABBCCCC, resulting in diverse AABBCC plants. Genetic diversity can be further expanded by crossbreeding plants with different AABBCC genome sets. Although genetic stability is necessary to ensure in the later generations, the results obtained in this study show that the use of somatic hybrids with excess genomes is an effective strategy for creating innovative crops.
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Affiliation(s)
- Teppei Shinke
- Faculty of Agriculture, Kindai University, Nara, 631-8505, Japan
| | - Akira Yamazaki
- Faculty of Agriculture, Kindai University, Nara, 631-8505, Japan
| | - Soraha Nakamura
- Faculty of Agriculture, Kindai University, Nara, 631-8505, Japan
| | - Hiroshi Kudoh
- Center for Ecological Research, Kyoto University, Hirano 2-509-3, Otsu, 520-2113, Japan
| | - Munetaka Hosokawa
- Faculty of Agriculture, Kindai University, Nara, 631-8505, Japan.
- Agricultural Technology and Innovation Research Institute (ATIRI), Kindai University, Nara, 631-8505, Japan.
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Lv Z, Addo Nyarko C, Ramtekey V, Behn H, Mason AS. Defining autopolyploidy: Cytology, genetics, and taxonomy. AMERICAN JOURNAL OF BOTANY 2024; 111:e16292. [PMID: 38439575 DOI: 10.1002/ajb2.16292] [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: 09/15/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 03/06/2024]
Abstract
Autopolyploidy is taxonomically defined as the presence of more than two copies of each genome within an organism or species, where the genomes present must all originate within the same species. Alternatively, "genetic" or "cytological" autopolyploidy is defined by polysomic inheritance: random pairing and segregation of the four (or more) homologous chromosomes present, with no preferential pairing partners. In this review, we provide an overview of methods used to categorize species as taxonomic and cytological autopolyploids, including both modern and obsolete cytological methods, marker-segregation-based and genomics methods. Subsequently, we also investigated how frequently polysomic inheritance has been reliably documented in autopolyploids. Pure or predominantly polysomic inheritance was documented in 39 of 43 putative autopolyploid species where inheritance data was available (91%) and in seven of eight synthetic autopolyploids, with several cases of more mixed inheritance within species. We found no clear cases of autopolyploids with disomic inheritance, which was likely a function of our search methodology. Interestingly, we found seven species with purely polysomic inheritance and another five species with partial or predominant polysomic inheritance that appear to be taxonomic allopolyploids. Our results suggest that observations of polysomic inheritance can lead to relabeling of taxonomically allopolyploid species as autopolyploid and highlight the need for further cytogenetic and genomic investigation into polyploid origins and inheritance types.
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Affiliation(s)
- Zhenling Lv
- Plant Breeding Department, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
| | - Charles Addo Nyarko
- Plant Breeding Department, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
| | - Vinita Ramtekey
- Plant Breeding Department, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
- ICAR-Indian Institute of Seed Science, 275103, Mau, India
| | - Helen Behn
- Plant Breeding Department, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
| | - Annaliese S Mason
- Plant Breeding Department, University of Bonn, Kirschallee 1, 53115, Bonn, Germany
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Paritosh K, Rajarammohan S, Yadava SK, Sharma S, Verma R, Mathur S, Mukhopadhyay A, Gupta V, Pradhan AK, Kaur J, Pental D. A chromosome-scale assembly of Brassica carinata (BBCC) accession HC20 containing resistance to multiple pathogens and an early generation assessment of introgressions into B. juncea (AABB). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 119:762-782. [PMID: 38722594 DOI: 10.1111/tpj.16794] [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: 07/01/2023] [Revised: 04/04/2024] [Accepted: 04/22/2024] [Indexed: 07/16/2024]
Abstract
Brassica carinata (BBCC) commonly referred to as Ethiopian mustard is a natural allotetraploid containing the genomes of Brassica nigra (BB) and Brassica oleracea (CC). It is an oilseed crop endemic to the northeastern regions of Africa. Although it is under limited cultivation, B. carinata is valuable as it is resistant/highly tolerant to most of the pathogens affecting widely cultivated Brassica species of the U's triangle. We report a chromosome-scale genome assembly of B. carinata accession HC20 using long-read Oxford Nanopore sequencing and Bionano optical maps. The assembly has a scaffold N50 of ~39.8 Mb and covers ~1.11 Gb of the genome. We compared the long-read genome assemblies of the U's triangle species and found extensive gene collinearity between the diploids and allopolyploids with no evidence of major gene losses. Therefore, B. juncea (AABB), B. napus (AACC), and B. carinata can be regarded as strict allopolyploids. We cataloged the nucleotide-binding and leucine-rich repeat immune receptor (NLR) repertoire of B. carinata and, identified 465 NLRs, and compared these with the NLRs in the other Brassica species. We investigated the extent and nature of early-generation genomic interactions between the constituent genomes of B. carinata and B. juncea in interspecific crosses between the two species. Besides the expected recombination between the constituent B genomes, extensive homoeologous exchanges were observed between the A and C genomes. Interspecific crosses, therefore, can be used for transferring disease resistance from B. carinata to B. juncea and broadening the genetic base of the two allotetraploid species.
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Affiliation(s)
- Kumar Paritosh
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | | | - Satish Kumar Yadava
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | - Sarita Sharma
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | - Rashmi Verma
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | - Shikha Mathur
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | - Arundhati Mukhopadhyay
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | - Vibha Gupta
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | - Akshay K Pradhan
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
| | - Jagreet Kaur
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
- Department of Genetics, University of Delhi South Campus, New Delhi, 110021, India
| | - Deepak Pental
- Centre for Genetic Manipulation of Crop Plants, University of Delhi South Campus, New Delhi, 110021, India
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Reis Soares N, Costa ZP, Marques JPR, Garsmeur O, Sampaio Carneiro M, Monteiro Vitorello CB, D'Hont A, Vieira MLC. First investigation into the genetic control of meiosis in sugarcane. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:2094-2107. [PMID: 38523577 DOI: 10.1111/tpj.16731] [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: 11/15/2023] [Revised: 01/28/2024] [Accepted: 03/05/2024] [Indexed: 03/26/2024]
Abstract
The sugarcane (Saccharum spp.) genome is one of the most complex of all. Modern varieties are highly polyploid and aneuploid as a result of hybridization between Saccharum officinarum and S. spontaneum. Little research has been done on meiotic control in polyploid species, with the exception of the wheat Ph1 locus harboring the ZIP4 gene (TaZIP4-B2) which promotes pairing between homologous chromosomes while suppressing crossover between homeologs. In sugarcane, despite its interspecific origin, bivalent association is favored, and multivalents, if any, are resolved at the end of prophase I. Thus, our aim herein was to investigate the purported genetic control of meiosis in the parental species and in sugarcane itself. We investigated the ZIP4 gene and immunolocalized meiotic proteins, namely synaptonemal complex proteins Zyp1 and Asy1. The sugarcane ZIP4 gene is located on chromosome 2 and expressed more abundantly in flowers, a similar profile to that found for TaZIP4-B2. ZIP4 expression is higher in S. spontaneum a neoautopolyploid, with lower expression in S. officinarum, a stable octoploid species. The sugarcane Zip4 protein contains a TPR domain, essential for scaffolding. Its 3D structure was also predicted, and it was found to be very similar to that of TaZIP4-B2, reflecting their functional relatedness. Immunolocalization of the Asy1 and Zyp1 proteins revealed that S. officinarum completes synapsis. However, in S. spontaneum and SP80-3280 (a modern variety), no nuclei with complete synapsis were observed. Importantly, our results have implications for sugarcane cytogenetics, genetic mapping, and genomics.
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Affiliation(s)
- Nina Reis Soares
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, 13418-900, Piracicaba, São Paulo, Brazil
| | - Zirlane Portugal Costa
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, 13418-900, Piracicaba, São Paulo, Brazil
| | - João Paulo Rodrigues Marques
- Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, SP, 13635-900, Pirassununga, São Paulo, Brazil
| | - Olivier Garsmeur
- CIRAD (Centre de Coopération Internationale en Recherche Agronomique pour le Développement), UMR AGAP, F-34398, Montpellier, France
- AGAP, Univ Montpellier, CIRAD, INRA, Montpellier SupAgro, 34060, Montpellier, France
| | - Monalisa Sampaio Carneiro
- Departamento de Biotecnologia e Produção Vegetal e Animal, Centro de Ciências Agrárias, Universidade Federal de São Carlos, 13604-900, Araras, São Paulo, Brazil
| | - Cláudia Barros Monteiro Vitorello
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, 13418-900, Piracicaba, São Paulo, Brazil
| | - Angélique D'Hont
- CIRAD (Centre de Coopération Internationale en Recherche Agronomique pour le Développement), UMR AGAP, F-34398, Montpellier, France
- AGAP, Univ Montpellier, CIRAD, INRA, Montpellier SupAgro, 34060, Montpellier, France
| | - Maria Lucia Carneiro Vieira
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, 13418-900, Piracicaba, São Paulo, Brazil
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Booker WW, Schrider DR. The genetic consequences of range expansion and its influence on diploidization in polyploids. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.10.18.562992. [PMID: 37905020 PMCID: PMC10614938 DOI: 10.1101/2023.10.18.562992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Despite newly formed polyploids being subjected to myriad fitness consequences, the relative prevalence of polyploidy both contemporarily and in ancestral branches of the tree of life suggests alternative advantages that outweigh these consequences. One proposed advantage is that polyploids may more easily colonize novel habitats such as deglaciated areas. However, previous research conducted in diploids suggests that range expansion comes with a fitness cost as deleterious mutations may fix rapidly on the expansion front. Here, we interrogate the potential consequences of expansion in polyploids by conducting spatially explicit forward-in-time simulations to investigate how ploidy and inheritance patterns impact the relative ability of polyploids to expand their range. We show that under realistic dominance models, autopolyploids suffer greater fitness reductions than diploids as a result of range expansion due to the fixation of increased mutational load that is masked in the range core. Alternatively, the disomic inheritance of allopolyploids provides a shield to this fixation resulting in minimal fitness consequences. In light of this advantage provided by disomy, we investigate how range expansion may influence cytogenetic diploidization through the reversion to disomy in autotetraploids. We show that under a wide range of parameters investigated for two models of diploidization, disomy frequently evolves more rapidly on the expansion front than in the range core, and that this dynamic inheritance model has additional effects on fitness. Together our results point to a complex interaction between dominance, ploidy, inheritance, and recombination on fitness as a population spreads across a geographic range.
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Affiliation(s)
- William W. Booker
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27514-2916, United States of America
| | - Daniel R. Schrider
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27514-2916, United States of America
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7
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Chéron F, Petiot V, Lambing C, White C, Serra H. Incorrect recombination partner associations contribute to meiotic instability of neo-allopolyploid Arabidopsis suecica. THE NEW PHYTOLOGIST 2024; 241:2025-2038. [PMID: 38158491 DOI: 10.1111/nph.19487] [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: 11/21/2023] [Accepted: 11/29/2023] [Indexed: 01/03/2024]
Abstract
Combining two or more related homoeologous genomes in a single nucleus, newly formed allopolyploids must rapidly adapt meiosis to restore balanced chromosome segregation, production of euploid gametes and fertility. The poor fertility of such neo-allopolyploids thus strongly selects for the limitation or avoidance of genetic crossover formation between homoeologous chromosomes. In this study, we have reproduced the interspecific hybridization between Arabidopsis thaliana and Arabidopsis arenosa leading to the allotetraploid Arabidopsis suecica and have characterized the first allopolyploid meioses. First-generation neo-allopolyploid siblings vary considerably in fertility, meiotic behavior and levels of homoeologous recombination. We show that centromere dynamics at early meiosis is altered in synthetic neo-allopolyploids compared with evolved A. suecica, with a significant increase in homoeologous centromere interactions at zygotene. At metaphase I, the presence of multivalents involving homoeologous chromosomes confirms that homoeologous recombination occurs in the first-generation synthetic allopolyploid plants and this is associated with a significant reduction in homologous recombination, compared to evolved A. suecica. Together, these data strongly suggest that the fidelity of recombination partner choice, likely during the DNA invasion step, is strongly impaired during the first meiosis of neo-allopolyploids and requires subsequent adaptation.
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Affiliation(s)
- Floriane Chéron
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, Inserm U1103, Université Clermont Auvergne, 63000, Clermont-Ferrand, France
| | - Valentine Petiot
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, Inserm U1103, Université Clermont Auvergne, 63000, Clermont-Ferrand, France
| | | | - Charles White
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, Inserm U1103, Université Clermont Auvergne, 63000, Clermont-Ferrand, France
| | - Heïdi Serra
- Genetics, Reproduction and Development Institute (iGReD), CNRS UMR 6293, Inserm U1103, Université Clermont Auvergne, 63000, Clermont-Ferrand, France
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8
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Duan T, Sicard A, Glémin S, Lascoux M. Separating phases of allopolyploid evolution with resynthesized and natural Capsella bursa-pastoris. eLife 2024; 12:RP88398. [PMID: 38189348 PMCID: PMC10945474 DOI: 10.7554/elife.88398] [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] [Indexed: 01/09/2024] Open
Abstract
Allopolyploidization is a frequent evolutionary transition in plants that combines whole-genome duplication (WGD) and interspecific hybridization. The genome of an allopolyploid species results from initial interactions between parental genomes and long-term evolution. Distinguishing the contributions of these two phases is essential to understanding the evolutionary trajectory of allopolyploid species. Here, we compared phenotypic and transcriptomic changes in natural and resynthesized Capsella allotetraploids with their diploid parental species. We focused on phenotypic traits associated with the selfing syndrome and on transcription-level phenomena such as expression-level dominance (ELD), transgressive expression (TRE), and homoeolog expression bias (HEB). We found that selfing syndrome, high pollen, and seed quality in natural allotetraploids likely resulted from long-term evolution. Similarly, TRE and most down-regulated ELD were only found in natural allopolyploids. Natural allotetraploids also had more ELD toward the self-fertilizing parental species than resynthesized allotetraploids, mirroring the establishment of the selfing syndrome. However, short-term changes mattered, and 40% of the cases of ELD in natural allotetraploids were already observed in resynthesized allotetraploids. Resynthesized allotetraploids showed striking variation of HEB among chromosomes and individuals. Homoeologous synapsis was its primary source and may still be a source of genetic variation in natural allotetraploids. In conclusion, both short- and long-term mechanisms contributed to transcriptomic and phenotypic changes in natural allotetraploids. However, the initial gene expression changes were largely reshaped during long-term evolution leading to further morphological changes.
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Affiliation(s)
- Tianlin Duan
- Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala UniversityUppsalaSweden
| | - Adrien Sicard
- Department of Plant Biology, Swedish University of Agricultural SciencesUppsalaSweden
| | - Sylvain Glémin
- Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala UniversityUppsalaSweden
- UMR CNRS 6553 ECOBIO, Campus BeaulieuRennesFrance
| | - Martin Lascoux
- Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala UniversityUppsalaSweden
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Bird KA, Pires JC, VanBuren R, Xiong Z, Edger PP. Dosage-sensitivity shapes how genes transcriptionally respond to allopolyploidy and homoeologous exchange in resynthesized Brassica napus. Genetics 2023; 225:iyad114. [PMID: 37338008 PMCID: PMC10471226 DOI: 10.1093/genetics/iyad114] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/10/2023] [Accepted: 06/12/2023] [Indexed: 06/21/2023] Open
Abstract
The gene balance hypothesis proposes that selection acts on the dosage (i.e. copy number) of genes within dosage-sensitive portions of networks, pathways, and protein complexes to maintain balanced stoichiometry of interacting proteins, because perturbations to stoichiometric balance can result in reduced fitness. This selection has been called dosage balance selection. Dosage balance selection is also hypothesized to constrain expression responses to dosage changes, making dosage-sensitive genes (those encoding members of interacting proteins) experience more similar expression changes. In allopolyploids, where whole-genome duplication involves hybridization of diverged lineages, organisms often experience homoeologous exchanges that recombine, duplicate, and delete homoeologous regions of the genome and alter the expression of homoeologous gene pairs. Although the gene balance hypothesis makes predictions about the expression response to homoeologous exchanges, they have not been empirically tested. We used genomic and transcriptomic data from 6 resynthesized, isogenic Brassica napus lines over 10 generations to identify homoeologous exchanges, analyzed expression responses, and tested for patterns of genomic imbalance. Groups of dosage-sensitive genes had less variable expression responses to homoeologous exchanges than dosage-insensitive genes, a sign that their relative dosage is constrained. This difference was absent for homoeologous pairs whose expression was biased toward the B. napus A subgenome. Finally, the expression response to homoeologous exchanges was more variable than the response to whole-genome duplication, suggesting homoeologous exchanges create genomic imbalance. These findings expand our knowledge of the impact of dosage balance selection on genome evolution and potentially connect patterns in polyploid genomes over time, from homoeolog expression bias to duplicate gene retention.
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Affiliation(s)
- Kevin A Bird
- Department of Horticulture, Michigan State University, East Lansing, MI 48824, USA
- Ecology, Evolution, and Behavior Program, Michigan State University, East Lansing, MI 48824, USA
| | - J Chris Pires
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Robert VanBuren
- Department of Horticulture, Michigan State University, East Lansing, MI 48824, USA
- Plant Resilience Institute, Michigan State University, East Lansing, MI 48824, USA
| | - Zhiyong Xiong
- Key Laboratory of Herbage and Endemic Crop Biotechnology, Inner Mongolia University, Hohhot, Inner Mongolia 010070, China
| | - Patrick P Edger
- Department of Horticulture, Michigan State University, East Lansing, MI 48824, USA
- Ecology, Evolution, and Behavior Program, Michigan State University, East Lansing, MI 48824, USA
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Katche EI, Schierholt A, Schiessl SV, He F, Lv Z, Batley J, Becker HC, Mason AS. Genetic factors inherited from both diploid parents interact to affect genome stability and fertility in resynthesized allotetraploid Brassica napus. G3 (BETHESDA, MD.) 2023; 13:jkad136. [PMID: 37313757 PMCID: PMC10411605 DOI: 10.1093/g3journal/jkad136] [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: 04/24/2023] [Revised: 04/24/2023] [Accepted: 05/31/2023] [Indexed: 06/15/2023]
Abstract
Established allopolyploids are known to be genomically stable and fertile. However, in contrast, most newly resynthesized allopolyploids are infertile and meiotically unstable. Identifying the genetic factors responsible for genome stability in newly formed allopolyploid is key to understanding how 2 genomes come together to form a species. One hypothesis is that established allopolyploids may have inherited specific alleles from their diploid progenitors which conferred meiotic stability. Resynthesized Brassica napus lines are often unstable and infertile, unlike B. napus cultivars. We tested this hypothesis by characterizing 41 resynthesized B. napus lines produced by crosses between 8 Brassica rapa and 8 Brassica oleracea lines for copy number variation resulting from nonhomologous recombination events and fertility. We resequenced 8 B. rapa and 5 B. oleracea parent accessions and analyzed 19 resynthesized lines for allelic variation in a list of meiosis gene homologs. SNP genotyping was performed using the Illumina Infinium Brassica 60K array for 3 individuals per line. Self-pollinated seed set and genome stability (number of copy number variants) were significantly affected by the interaction between both B. rapa and B. oleracea parental genotypes. We identified 13 putative meiosis gene candidates which were significantly associated with frequency of copy number variants and which contained putatively harmful mutations in meiosis gene haplotypes for further investigation. Our results support the hypothesis that allelic variants inherited from parental genotypes affect genome stability and fertility in resynthesized rapeseed.
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Affiliation(s)
- Elizabeth Ihien Katche
- Plant Breeding Department, University of Bonn, Bonn 53115, Germany
- Department of Plant Breeding, Justus Liebig University, Giessen 35392, Germany
| | - Antje Schierholt
- Department of Crop Sciences, Division of Plant Breeding Methodology, Georg-August University Göttingen, Göttingen 37073, Germany
| | - Sarah-Veronica Schiessl
- Department of Plant Breeding, Justus Liebig University, Giessen 35392, Germany
- Department of Botany and Molecular Evolution, Senckenberg Research Institute and Natural History Museum Frankfurt, Frankfurt am Main D-60325, Germany
| | - Fei He
- Plant Breeding Department, University of Bonn, Bonn 53115, Germany
| | - Zhenling Lv
- Plant Breeding Department, University of Bonn, Bonn 53115, Germany
- Department of Plant Breeding, Justus Liebig University, Giessen 35392, Germany
| | - Jacqueline Batley
- School of Biological Sciences, University of Western Australia, Perth, WA 6009, Australia
| | - Heiko C Becker
- Department of Crop Sciences, Division of Plant Breeding Methodology, Georg-August University Göttingen, Göttingen 37073, Germany
| | - Annaliese S Mason
- Plant Breeding Department, University of Bonn, Bonn 53115, Germany
- Department of Plant Breeding, Justus Liebig University, Giessen 35392, Germany
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11
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Deb SK, Edger PP, Pires JC, McKain MR. Patterns, mechanisms, and consequences of homoeologous exchange in allopolyploid angiosperms: a genomic and epigenomic perspective. THE NEW PHYTOLOGIST 2023; 238:2284-2304. [PMID: 37010081 DOI: 10.1111/nph.18927] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 03/16/2023] [Indexed: 05/19/2023]
Abstract
Allopolyploids result from hybridization between different evolutionary lineages coupled with genome doubling. Homoeologous chromosomes (chromosomes with common shared ancestry) may undergo recombination immediately after allopolyploid formation and continue over successive generations. The outcome of this meiotic pairing behavior is dynamic and complex. Homoeologous exchanges (HEs) may lead to the formation of unbalanced gametes, reduced fertility, and selective disadvantage. By contrast, HEs could act as sources of novel evolutionary substrates, shifting the relative dosage of parental gene copies, generating novel phenotypic diversity, and helping the establishment of neo-allopolyploids. However, HE patterns vary among lineages, across generations, and even within individual genomes and chromosomes. The causes and consequences of this variation are not fully understood, though interest in this evolutionary phenomenon has increased in the last decade. Recent technological advances show promise in uncovering the mechanistic basis of HEs. Here, we describe recent observations of the common patterns among allopolyploid angiosperm lineages, underlying genomic and epigenomic features, and consequences of HEs. We identify critical research gaps and discuss future directions with far-reaching implications in understanding allopolyploid evolution and applying them to the development of important phenotypic traits of polyploid crops.
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Affiliation(s)
- Sontosh K Deb
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
- Department of Forestry and Environmental Science, Shahjalal University of Science and Technology, Sylhet, 3114, Bangladesh
| | - Patrick P Edger
- Department of Horticulture, Michigan State University, East Lansing, MI, 48823, USA
- Genetics and Genome Sciences Program, Michigan State University, East Lansing, MI, 48823, USA
| | - J Chris Pires
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Michael R McKain
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
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12
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Draeger TN, Rey MD, Hayta S, Smedley M, Alabdullah AK, Moore G, Martín AC. ZIP4 is required for normal progression of synapsis and for over 95% of crossovers in wheat meiosis. FRONTIERS IN PLANT SCIENCE 2023; 14:1189998. [PMID: 37324713 PMCID: PMC10266424 DOI: 10.3389/fpls.2023.1189998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 04/26/2023] [Indexed: 06/17/2023]
Abstract
Tetraploid (AABB) and hexaploid (AABBDD) wheat have multiple sets of similar chromosomes, with successful meiosis and preservation of fertility relying on synapsis and crossover (CO) formation only taking place between homologous chromosomes. In hexaploid wheat, the major meiotic gene TaZIP4-B2 (Ph1) on chromosome 5B, promotes CO formation between homologous chromosomes, whilst suppressing COs between homeologous (related) chromosomes. In other species, ZIP4 mutations eliminate approximately 85% of COs, consistent with loss of the class I CO pathway. Tetraploid wheat has three ZIP4 copies: TtZIP4-A1 on chromosome 3A, TtZIP4-B1 on 3B and TtZIP4-B2 on 5B. Here, we have developed single, double and triple zip4 TILLING mutants and a CRISPR Ttzip4-B2 mutant, to determine the effect of ZIP4 genes on synapsis and CO formation in the tetraploid wheat cultivar 'Kronos'. We show that disruption of two ZIP4 gene copies in Ttzip4-A1B1 double mutants, results in a 76-78% reduction in COs when compared to wild-type plants. Moreover, when all three copies are disrupted in Ttzip4-A1B1B2 triple mutants, COs are reduced by over 95%, suggesting that the TtZIP4-B2 copy may also affect class II COs. If this is the case, the class I and class II CO pathways may be interlinked in wheat. When ZIP4 duplicated and diverged from chromosome 3B on wheat polyploidization, the new 5B copy, TaZIP4-B2, could have acquired an additional function to stabilize both CO pathways. In tetraploid plants deficient in all three ZIP4 copies, synapsis is delayed and does not complete, consistent with our previous studies in hexaploid wheat, when a similar delay in synapsis was observed in a 59.3 Mb deletion mutant, ph1b, encompassing the TaZIP4-B2 gene on chromosome 5B. These findings confirm the requirement of ZIP4-B2 for efficient synapsis, and suggest that TtZIP4 genes have a stronger effect on synapsis than previously described in Arabidopsis and rice. Thus, ZIP4-B2 in wheat accounts for the two major phenotypes reported for Ph1, promotion of homologous synapsis and suppression of homeologous COs.
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Affiliation(s)
| | - María-Dolores Rey
- Agroforestry and Plant Biochemistry, Proteomics and Systems Biology, Department of Biochemistry and Molecular Biology, University of Córdoba, Córdoba, Spain
| | - Sadiye Hayta
- John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Mark Smedley
- John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | | | - Graham Moore
- John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Azahara C. Martín
- Department of Plant Genetic Improvement, Institute for Sustainable Agriculture, Spanish National Research Council (CSIC), Córdoba, Spain
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13
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Yu J, Lei S, Fang S, Tai N, Yu W, Yang Z, Gu L, Wang H, Du X, Zhu B, Cai M. Identification, Characterization, and Cytological Analysis of Several Unexpected Hybrids Derived from Reciprocal Crosses between Raphanobrassica and Its Diploid Parents. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12091875. [PMID: 37176933 PMCID: PMC10181067 DOI: 10.3390/plants12091875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 04/28/2023] [Accepted: 05/01/2023] [Indexed: 05/15/2023]
Abstract
Interspecific hybridization and accompanying backcross between crops and relatives have been recognized as a powerful method to broaden genetic diversity and transfer desirable adaptive traits. Crosses between radish (Raphanus sativus, RR, 2n = 18) and Brassica oleracea (CC, 2n = 18), which formed allotetraploid Raphanobrassica (RRCC, 2n = 36), initiated the construction of resynthetic allopolyploids. However, these progenies from the backcrosses between Raphanobrassica and the two diploid parents have not been well deciphered. Herein, thousands of backcrosses using both Raphanobrassica and the two diploid parents as pollen donors were employed. Several hybrids with expected (2n = 27) and unexpected chromosome numbers (2n = 26 and 2n = 36) were obtained. Fluorescence in situ hybridization (FISH) analysis with R-genome-specific sequences as probes demonstrated that the genome structures of the two expected hybrids were RRC and CCR, and the genome structures of the three unexpected hybrids were RRRC, CCCR, and RRC' (harbouring an incomplete C genome). The unexpected hybrids with extra R or C genomes showed similar phenotypic characteristics to their expected hybrids. FISH analysis with C-genome-specific sequences as probes demonstrated that the unexpected allotetraploid hybrids exhibited significantly more intergenomic chromosome pairings than the expected hybrids. The expected and unexpected hybrids provide not only novel germplasm resources for the breeding of radish and B. oleracea but also very important genetic material for genome dosage analysis.
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Affiliation(s)
- Jie Yu
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Shaolin Lei
- Guizhou Institute of Oil Crops, Guizhou Academy of Agricultural Sciences, Guiyang 550009, China
| | - Shiting Fang
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Niufang Tai
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Wei Yu
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Ziwei Yang
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Lei Gu
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Hongcheng Wang
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Xuye Du
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Bin Zhu
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
| | - Mengxian Cai
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China
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14
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Novikova PY, Kolesnikova UK, Scott AD. Ancestral self-compatibility facilitates the establishment of allopolyploids in Brassicaceae. PLANT REPRODUCTION 2023; 36:125-138. [PMID: 36282331 PMCID: PMC9957919 DOI: 10.1007/s00497-022-00451-6] [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: 06/29/2022] [Accepted: 09/20/2022] [Indexed: 05/15/2023]
Abstract
Self-incompatibility systems based on self-recognition evolved in hermaphroditic plants to maintain genetic variation of offspring and mitigate inbreeding depression. Despite these benefits in diploid plants, for polyploids who often face a scarcity of mating partners, self-incompatibility can thwart reproduction. In contrast, self-compatibility provides an immediate advantage: a route to reproductive viability. Thus, diploid selfing lineages may facilitate the formation of new allopolyploid species. Here, we describe the mechanism of establishment of at least four allopolyploid species in Brassicaceae (Arabidopsis suecica, Arabidopsis kamchatica, Capsella bursa-pastoris, and Brassica napus), in a manner dependent on the prior loss of the self-incompatibility mechanism in one of the ancestors. In each case, the degraded S-locus from one parental lineage was dominant over the functional S-locus of the outcrossing parental lineage. Such dominant loss-of-function mutations promote an immediate transition to selfing in allopolyploids and may facilitate their establishment.
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Affiliation(s)
- Polina Yu Novikova
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, 50829, Cologne, Germany.
| | - Uliana K Kolesnikova
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, 50829, Cologne, Germany
| | - Alison Dawn Scott
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, 50829, Cologne, Germany
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15
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Bomblies K. Learning to tango with four (or more): the molecular basis of adaptation to polyploid meiosis. PLANT REPRODUCTION 2023; 36:107-124. [PMID: 36149479 PMCID: PMC9957869 DOI: 10.1007/s00497-022-00448-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/10/2022] [Indexed: 05/29/2023]
Abstract
Polyploidy, which arises from genome duplication, has occurred throughout the history of eukaryotes, though it is especially common in plants. The resulting increased size, heterozygosity, and complexity of the genome can be an evolutionary opportunity, facilitating diversification, adaptation and the evolution of functional novelty. On the other hand, when they first arise, polyploids face a number of challenges, one of the biggest being the meiotic pairing, recombination and segregation of the suddenly more than two copies of each chromosome, which can limit their fertility. Both for developing polyploidy as a crop improvement tool (which holds great promise due to the high and lasting multi-stress resilience of polyploids), as well as for our basic understanding of meiosis and plant evolution, we need to know both the specific nature of the challenges polyploids face, as well as how they can be overcome in evolution. In recent years there has been a dramatic uptick in our understanding of the molecular basis of polyploid adaptations to meiotic challenges, and that is the focus of this review.
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Affiliation(s)
- Kirsten Bomblies
- Plant Evolutionary Genetics, Institute of Plant Molecular Biology, Department of Biology, ETH Zürich, Zurich, Switzerland.
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16
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Oruganti V, Toegelová H, Pečinka A, Madlung A, Schneeberger K. Rapid large-scale genomic introgression in Arabidopsis suecica via an autoallohexaploid bridge. Genetics 2023; 223:iyac132. [PMID: 36124968 PMCID: PMC9910397 DOI: 10.1093/genetics/iyac132] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/24/2022] [Indexed: 11/14/2022] Open
Abstract
Gene flow between species in the genus Arabidopsis occurs in significant amounts, but how exactly gene flow is achieved is not well understood. Polyploidization may be one avenue to explain gene flow between species. One problem, however, with polyploidization as a satisfying explanation is the occurrence of lethal genomic instabilities in neopolyploids as a result of genomic exchange, erratic meiotic behavior, and genomic shock. We have created an autoallohexaploid by pollinating naturally co-occurring diploid Arabidopsis thaliana with allotetraploid Arabidopsis suecica (an allotetraploid composed of A. thaliana and Arabidopsis arenosa). Its triploid offspring underwent spontaneous genome duplication and was used to generate a multigenerational pedigree. Using genome resequencing, we show that 2 major mechanisms promote stable genomic exchange in this population. Legitimate meiotic recombination and chromosome segregation between the autopolyploid chromosomes of the 2 A. thaliana genomes occur without any obvious bias for the parental origin and combine the A. thaliana haplotypes from the A. thaliana parent with the A. thaliana haplotypes from A. suecica similar to purely autopolyploid plants. In addition, we repeatedly observed that occasional exchanges between regions of the homoeologous chromosomes are tolerated. The combination of these mechanisms may result in gene flow leading to stable introgression in natural populations. Unlike the previously reported resynthesized neoallotetraploid A. suecica, this population of autoallohexaploids contains mostly vigorous, and genetically, cytotypically, and phenotypically variable individuals. We propose that naturally formed autoallohexaploid populations might serve as an intermediate bridge between diploid and polyploid species, which can facilitate gene flow rapidly and efficiently.
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Affiliation(s)
- Vidya Oruganti
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
| | - Helena Toegelová
- Institute of Experimental Botany of the Czech Academy of Sciences, 77900 Olomouc, Czech Republic
| | - Aleš Pečinka
- Institute of Experimental Botany of the Czech Academy of Sciences, 77900 Olomouc, Czech Republic
| | - Andreas Madlung
- Department of Biology, University of Puget Sound, Tacoma, WA 98416, USA
| | - Korbinian Schneeberger
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
- Department of Genetics, Faculty of Biology, Ludwig Maximilian Universität München, 82152 Planegg-Martinsried, Germany
- Cluster of Excellence on Plant Sciences, Heinrich-Heine University, Düsseldorf, Germany
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17
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Inference of Polyploid Origin and Inheritance Mode from Population Genomic Data. Methods Mol Biol 2023; 2545:279-295. [PMID: 36720819 DOI: 10.1007/978-1-0716-2561-3_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Whole-genome duplications yield varied chromosomal pairing patterns, ranging from strictly bivalent to multivalent, resulting in disomic and polysomic inheritance modes. In the bivalent case, homeologous chromosomes form pairs, where in a multivalent pattern all copies are homologous and are therefore free to pair and recombine. As sufficient sequencing data is more readily available than high-quality cytological assessments of meiotic behavior or population genetic assessment of allelic segregation, especially for non-model organisms, bioinformatics approaches to infer origins and inheritance modes of polyploids using short-read sequencing data are attractive. Here we describe two such approaches, where the first is based on distributions of allelic read depth at heterozygous sites within an individual, as the expectations of such distributions are different for disomic and polysomic inheritance modes. The second approach is more laborious and based on a phylogenetic assessment of partially phased haplotypes of a polyploid in comparison to the closest diploid relatives. We discuss the sources of deviations from expected inheritance patterns, advantages and pitfalls of both methods, effects of mating types on the performance of the methods, and possible future developments.
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18
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Tian Z, Ji C, Xie Z, Shi X, Tian B, Cao G, Wei X, Yang Y, Wei F, Shi G. Integrated cytological and transcriptomic analysis reveals insights into pollen fertility in newly synthetic Brassica allohexaploids. FRONTIERS IN PLANT SCIENCE 2023; 13:1096804. [PMID: 36714744 PMCID: PMC9880477 DOI: 10.3389/fpls.2022.1096804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 12/21/2022] [Indexed: 06/18/2023]
Abstract
Trigenomic Brassica allohexaploids (AABBCC, 2n = 6x = 54) have great potential in oilseed breeding and genetic diversity. However, Brassica allohexaploids do not exist naturally, and the underlying mechanism regulating pollen fertility in artificially synthesized Brassica allohexaploids is still unclear. In this study, synthetic Brassica allohexaploids were produced by crossing allotetraploid B. carinata (BBCC, 2n = 4x = 34) and diploid B. rapa (AA, 2n = 2x = 20), followed by chromosome doubling. The results showed that the pollen fertility was significantly reduced and the pollen structures were mostly distorted, but the nursing anther tapetum developed normally in the synthetic Brassica allohexaploids. Furthermore, the data showed that the meiotic events occurred irregularly with uneven chromosome segregation and microspore development appeared mostly abnormal. Transcription analysis showed that the upregulation of genes related to the negative regulation of flower development and the downregulation of genes related to chromosome segregation might play an essential role in reduction of pollen fertility in the Brassica allohexaploids. In conclusion, this study elucidated the related mechanisms affecting pollen fertility during male gametophytic development at the cytological and transcriptomic levels in the newly synthesized Brassica allohexaploids.
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Affiliation(s)
- Zhaoran Tian
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Chengyan Ji
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T&R Base of Zhengzhou University, Zhengzhou, China
| | - Zhengqing Xie
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Xinjie Shi
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T&R Base of Zhengzhou University, Zhengzhou, China
| | - Baoming Tian
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Gangqiang Cao
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Xiaochun Wei
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T&R Base of Zhengzhou University, Zhengzhou, China
| | - Yan Yang
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Fang Wei
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Gongyao Shi
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
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19
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Crop Improvement: Where Are We Now? BIOLOGY 2022; 11:biology11101373. [PMID: 36290279 PMCID: PMC9598755 DOI: 10.3390/biology11101373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 11/17/2022]
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20
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Sohn SI, Thamilarasan SK, Pandian S, Oh YJ, Ryu TH, Lee GS, Shin EK. Interspecific Hybridization of Transgenic Brassica napus and Brassica rapa-An Overview. Genes (Basel) 2022; 13:genes13081442. [PMID: 36011353 PMCID: PMC9407623 DOI: 10.3390/genes13081442] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/12/2022] [Accepted: 08/12/2022] [Indexed: 11/16/2022] Open
Abstract
In nature, interspecific hybridization occurs frequently and can contribute to the production of new species or the introgression of beneficial adaptive features between species. It has great potential in agricultural systems to boost the process of targeted crop improvement. In the advent of genetically modified (GM) crops, it has a disadvantage that it involves the transgene escaping to unintended plants, which could result in non-specific weedy crops. Several crop species in the Brassica genus have close kinship: canola (Brassica napus) is an ancestral hybrid of B. rapa and B. oleracea and mustard species such as B. juncea, B. carinata, and B. nigra share common genomes. Hence, intraspecific hybridization among the Brassica species is most common, especially between B. napus and B. rapa. In general, interspecific hybrids cause numerous genetic and phenotypic changes in the parental lines. Consequently, their fitness and reproductive ability are also highly varied. In this review, we discuss the interspecific hybridization and reciprocal hybridization studies of B. napus and B. rapa and their potential in the controlled environment. Further, we address the fate of transgenes (herbicide resistance) and their ability to transfer to their progenies or generations. This could help us to understand the environmental influence of interspecific hybrids and how to effectively manage their transgene escape in the future.
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Affiliation(s)
- Soo-In Sohn
- Department of Agricultural Biotechnology, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
- Correspondence: ; Tel.: +82-063-238-4712
| | - Senthil Kumar Thamilarasan
- Department of Agricultural Biotechnology, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
| | - Subramani Pandian
- Department of Agricultural Biotechnology, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
| | - Young-Ju Oh
- Institute for Future Environment Ecology Co., Ltd., Jeonju 54883, Korea
| | - Tae-Hun Ryu
- Department of Agricultural Biotechnology, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
| | - Gang-Seob Lee
- Department of Agricultural Biotechnology, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
| | - Eun-Kyoung Shin
- Department of Agricultural Biotechnology, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea
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21
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Cai B, Wang T, Yue F, Harun A, Zhu B, Qian W, Ge X, Li Z. Production and cytology of Brassica autoallohexaploids with two and four copies of two subgenomes. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2022; 135:2641-2653. [PMID: 35796761 DOI: 10.1007/s00122-022-04136-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 05/22/2022] [Indexed: 06/15/2023]
Abstract
Different digenomic Brassica autoallohexaploids were produced from the crosses of three allotetraploids and ancestral diploids and characterized for the cytological behavior of two subgenomes with two and four copies. Interspecific hybridization and allopolyploidization present an important pathway for plant evolution and breeding. In this study, different types of digenomic autoallohexaploids with two or four copies of two subgenomes (AAAACC, AACCCC, AAAABB, BBBBCC, BBCCCC) were synthesized by the crosses between three Brassica allotetraploids and their diploid progenitors and the chromosome doubling, and their meiotic behaviors were analyzed by fluorescence in situ hybridization (FISH). These autoallohexaploids showed some variations in pollen fertility and seed-sets and produced both euploid and aneuploid progenies with some chromosomes lost. Two subgenomes in these autoallohexaploids showed some aberrant pairings and segregations, and the degrees of meiotic regularity were negatively associated with the genome affinities. The chromosomes of the subgenome with four copies formed few quadrivalents with the average number < 2, and mainly paired as bivalents, and majority of the chromosomes from the subgenome with two copies gave the expected bivalents. The different extents of the equal and unequal segregations corresponded to the chromosome pairings. The development and cytological investigation of these autoallohexaploids provide not only the new germplasm for genetic research and breeding but also the new clues for the genome behavior and interplay between these subgenomes with different copies.
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Affiliation(s)
- Bowei Cai
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Tai Wang
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Fang Yue
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, People's Republic of China
| | - Arrashid Harun
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Bin Zhu
- School of Life Sciences, Guizhou Normal University, Guiyang, 550025, People's Republic of China
| | - Wei Qian
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, People's Republic of China
| | - Xianhong Ge
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
| | - Zaiyun Li
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
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22
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Blasio F, Prieto P, Pradillo M, Naranjo T. Genomic and Meiotic Changes Accompanying Polyploidization. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11010125. [PMID: 35009128 PMCID: PMC8747196 DOI: 10.3390/plants11010125] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/24/2021] [Accepted: 12/29/2021] [Indexed: 05/04/2023]
Abstract
Hybridization and polyploidy have been considered as significant evolutionary forces in adaptation and speciation, especially among plants. Interspecific gene flow generates novel genetic variants adaptable to different environments, but it is also a gene introgression mechanism in crops to increase their agronomical yield. An estimate of 9% of interspecific hybridization has been reported although the frequency varies among taxa. Homoploid hybrid speciation is rare compared to allopolyploidy. Chromosome doubling after hybridization is the result of cellular defects produced mainly during meiosis. Unreduced gametes, which are formed at an average frequency of 2.52% across species, are the result of altered spindle organization or orientation, disturbed kinetochore functioning, abnormal cytokinesis, or loss of any meiotic division. Meiotic changes and their genetic basis, leading to the cytological diploidization of allopolyploids, are just beginning to be understood especially in wheat. However, the nature and mode of action of homoeologous recombination suppressor genes are poorly understood in other allopolyploids. The merger of two independent genomes causes a deep modification of their architecture, gene expression, and molecular interactions leading to the phenotype. We provide an overview of genomic changes and transcriptomic modifications that particularly occur at the early stages of allopolyploid formation.
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Affiliation(s)
- Francesco Blasio
- Departamento de Genética, Fisiología y Microbiología, Facultad de Biología, Universidad Complutense de Madrid, 28040 Madrid, Spain; (F.B.); (M.P.)
| | - Pilar Prieto
- Plant Breeding Department, Institute for Sustainable Agriculture, Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC), Alameda del Obispo s/n, Apartado 4048, 14080 Cordova, Spain;
| | - Mónica Pradillo
- Departamento de Genética, Fisiología y Microbiología, Facultad de Biología, Universidad Complutense de Madrid, 28040 Madrid, Spain; (F.B.); (M.P.)
| | - Tomás Naranjo
- Departamento de Genética, Fisiología y Microbiología, Facultad de Biología, Universidad Complutense de Madrid, 28040 Madrid, Spain; (F.B.); (M.P.)
- Correspondence:
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23
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Morgan C, White MA, Franklin FCH, Zickler D, Kleckner N, Bomblies K. Evolution of crossover interference enables stable autopolyploidy by ensuring pairwise partner connections in Arabidopsis arenosa. Curr Biol 2021; 31:4713-4726.e4. [PMID: 34480856 PMCID: PMC8585506 DOI: 10.1016/j.cub.2021.08.028] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/23/2021] [Accepted: 08/09/2021] [Indexed: 11/25/2022]
Abstract
Polyploidy is a major driver of evolutionary change. Autopolyploids, which arise by within-species whole-genome duplication, carry multiple nearly identical copies of each chromosome. This presents an existential challenge to sexual reproduction. Meiotic chromosome segregation requires formation of DNA crossovers (COs) between two homologous chromosomes. How can this outcome be achieved when more than two essentially equivalent partners are available? We addressed this question by comparing diploid, neo-autotetraploid, and established autotetraploid Arabidopsis arenosa using new approaches for analysis of meiotic CO patterns in polyploids. We discover that crossover interference, the classical process responsible for patterning of COs in diploid meiosis, is defective in the neo-autotetraploid but robust in the established autotetraploid. The presented findings suggest that, initially, diploid-like interference fails to act effectively on multivalent pairing and accompanying pre-CO recombination interactions and that stable autopolyploid meiosis can emerge by evolution of a “supercharged” interference process, which can now act effectively on such configurations. Thus, the basic interference mechanism responsible for simplifying CO patterns along chromosomes in diploid meiosis has evolved the capability to also simplify CO patterns among chromosomes in autopolyploids, thereby promoting bivalent formation. We further show that evolution of stable autotetraploidy preadapts meiosis to higher ploidy, which in turn has interesting mechanistic and evolutionary implications. In a neo-autotetraploid, aberrant crossover interference confers aberrant meiosis In a stable autotetraploid, regular crossover interference confers regular meiosis Crossover and synaptic patterns point to evolution of “supercharged” interference Accordingly, evolution of stable autotetraploidy preadapts to higher ploidies
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Affiliation(s)
- Chris Morgan
- John Innes Centre, Colney Lane, Norwich NR4 7UH, UK
| | - Martin A White
- Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
| | | | - Denise Zickler
- University Paris-Saclay, Commissariat à l'Energie Atomique at aux Energies Alternatives (CEA), Centre National de la Recherche Scientifique (CNRS), Institute for Integrative Biology of the Cell (I2BC), 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette, France
| | - Nancy Kleckner
- Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA.
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Wang Y, van Rengs WMJ, Zaidan MWAM, Underwood CJ. Meiosis in crops: from genes to genomes. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:6091-6109. [PMID: 34009331 PMCID: PMC8483783 DOI: 10.1093/jxb/erab217] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 05/14/2021] [Indexed: 05/06/2023]
Abstract
Meiosis is a key feature of sexual reproduction. During meiosis homologous chromosomes replicate, recombine, and randomly segregate, followed by the segregation of sister chromatids to produce haploid cells. The unique genotypes of recombinant gametes are an essential substrate for the selection of superior genotypes in natural populations and in plant breeding. In this review we summarize current knowledge on meiosis in diverse monocot and dicot crop species and provide a comprehensive resource of cloned meiotic mutants in six crop species (rice, maize, wheat, barley, tomato, and Brassica species). Generally, the functional roles of meiotic proteins are conserved between plant species, but we highlight notable differences in mutant phenotypes. The physical lengths of plant chromosomes vary greatly; for instance, wheat chromosomes are roughly one order of magnitude longer than those of rice. We explore how chromosomal distribution for crossover recombination can vary between species. We conclude that research on meiosis in crops will continue to complement that in Arabidopsis, and alongside possible applications in plant breeding will facilitate a better understanding of how the different stages of meiosis are controlled in plant species.
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Affiliation(s)
- Yazhong Wang
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg, Cologne, Germany
| | - Willem M J van Rengs
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg, Cologne, Germany
| | - Mohd Waznul Adly Mohd Zaidan
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg, Cologne, Germany
| | - Charles J Underwood
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg, Cologne, Germany
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Soares NR, Mollinari M, Oliveira GK, Pereira GS, Vieira MLC. Meiosis in Polyploids and Implications for Genetic Mapping: A Review. Genes (Basel) 2021; 12:genes12101517. [PMID: 34680912 PMCID: PMC8535482 DOI: 10.3390/genes12101517] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 02/06/2023] Open
Abstract
Plant cytogenetic studies have provided essential knowledge on chromosome behavior during meiosis, contributing to our understanding of this complex process. In this review, we describe in detail the meiotic process in auto- and allopolyploids from the onset of prophase I through pairing, recombination, and bivalent formation, highlighting recent findings on the genetic control and mode of action of specific proteins that lead to diploid-like meiosis behavior in polyploid species. During the meiosis of newly formed polyploids, related chromosomes (homologous in autopolyploids; homologous and homoeologous in allopolyploids) can combine in complex structures called multivalents. These structures occur when multiple chromosomes simultaneously pair, synapse, and recombine. We discuss the effectiveness of crossover frequency in preventing multivalent formation and favoring regular meiosis. Homoeologous recombination in particular can generate new gene (locus) combinations and phenotypes, but it may destabilize the karyotype and lead to aberrant meiotic behavior, reducing fertility. In crop species, understanding the factors that control pairing and recombination has the potential to provide plant breeders with resources to make fuller use of available chromosome variations in number and structure. We focused on wheat and oilseed rape, since there is an abundance of elucidating studies on this subject, including the molecular characterization of the Ph1 (wheat) and PrBn (oilseed rape) loci, which are known to play a crucial role in regulating meiosis. Finally, we exploited the consequences of chromosome pairing and recombination for genetic map construction in polyploids, highlighting two case studies of complex genomes: (i) modern sugarcane, which has a man-made genome harboring two subgenomes with some recombinant chromosomes; and (ii) hexaploid sweet potato, a naturally occurring polyploid. The recent inclusion of allelic dosage information has improved linkage estimation in polyploids, allowing multilocus genetic maps to be constructed.
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Affiliation(s)
- Nina Reis Soares
- Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba 13400-918, Brazil; (N.R.S.); (G.K.O.); (G.S.P.)
| | - Marcelo Mollinari
- Bioinformatics Research Center, North Carolina State University, Raleigh, NC 27695-7566, USA;
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27695-7555, USA
| | - Gleicy K. Oliveira
- Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba 13400-918, Brazil; (N.R.S.); (G.K.O.); (G.S.P.)
| | - Guilherme S. Pereira
- Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba 13400-918, Brazil; (N.R.S.); (G.K.O.); (G.S.P.)
- Department of Agronomy, Federal University of Viçosa, Viçosa 36570-900, Brazil
| | - Maria Lucia Carneiro Vieira
- Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba 13400-918, Brazil; (N.R.S.); (G.K.O.); (G.S.P.)
- Correspondence:
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Zhang K, Mason AS, Farooq MA, Islam F, Quezada-Martinez D, Hu D, Yang S, Zou J, Zhou W. Challenges and prospects for a potential allohexaploid Brassica crop. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2021; 134:2711-2726. [PMID: 34089067 DOI: 10.1007/s00122-021-03845-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 04/23/2021] [Indexed: 05/28/2023]
Abstract
The production of a new allohexaploid Brassica crop (2n = AABBCC) is increasingly attracting international interest: a new allohexaploid crop could benefit from several major advantages over the existing Brassica diploid and allotetraploid species, combining genetic diversity and traits from all six crop species with additional allelic heterosis from the extra genome. Although early attempts to produce allohexaploids showed mixed results, recent technological and conceptual advances have provided promising leads to follow. However, there are still major challenges which exist before this new crop type can be realized: (1) incorporation of sufficient genetic diversity to form a basis for breeding and improvement of this potential crop species; (2) restoration of regular meiosis, as most allohexaploids are genetically unstable after formation; and (3) improvement of agronomic traits to the level of "elite" breeding material in the diploid and allotetraploid crop species. In this review, we outline these major prospects and challenges and propose possible plans to produce a stable, diverse and agronomically viable allohexaploid Brassica crop.
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Affiliation(s)
- Kangni Zhang
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China
| | - Annaliese S Mason
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Muhammad A Farooq
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China
| | - Faisal Islam
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China
| | - Daniela Quezada-Martinez
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Dandan Hu
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Su Yang
- College of Life Sciences, China Jiliang University, Hangzhou, 310018, China
| | - Jun Zou
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Weijun Zhou
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China.
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Abstract
Sex, as well as meiotic recombination between homologous chromosomes, is nearly ubiquitous among eukaryotes. In those species that use it, recombination is important for chromosome segregation during gamete production, and thus for fertility. Strikingly, although in most species only one crossover event per chromosome is required to ensure proper segregation, recombination rates vary considerably above this minimum and show variation within and among species. However, whether this variation in recombination is adaptive or neutral and what might shape it remain unclear. Empirical studies and theory support the idea that recombination is generally beneficial but can also have costs. Here, we review variation in genome-wide recombination rates, explore what might cause this, and discuss what is known about its mechanistic basis. We end by discussing the environmental sensitivity of meiosis and recombination rates, how these features may relate to adaptation, and their implications for a broader understanding of recombination rate evolution. Expected final online publication date for the Annual Review of Genetics, Volume 55 is November 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Ian R Henderson
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom;
| | - Kirsten Bomblies
- Plant Evolutionary Genetics, Institute of Molecular Plant Biology, Department of Biology, ETH Zürich, 8092 Zürich, Switzerland;
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28
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Li Z, McKibben MTW, Finch GS, Blischak PD, Sutherland BL, Barker MS. Patterns and Processes of Diploidization in Land Plants. ANNUAL REVIEW OF PLANT BIOLOGY 2021; 72:387-410. [PMID: 33684297 DOI: 10.1146/annurev-arplant-050718-100344] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Most land plants are now known to be ancient polyploids that have rediploidized. Diploidization involves many changes in genome organization that ultimately restore bivalent chromosome pairing and disomic inheritance, and resolve dosage and other issues caused by genome duplication. In this review, we discuss the nature of polyploidy and its impact on chromosome pairing behavior. We also provide an overview of two major and largely independent processes of diploidization: cytological diploidization and genic diploidization/fractionation. Finally, we compare variation in gene fractionation across land plants and highlight the differences in diploidization between plants and animals. Altogether, we demonstrate recent advancements in our understanding of variation in the patterns and processes of diploidization in land plants and provide a road map for future research to unlock the mysteries of diploidization and eukaryotic genome evolution.
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Affiliation(s)
- Zheng Li
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA; , , , , ,
| | - Michael T W McKibben
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA; , , , , ,
| | - Geoffrey S Finch
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA; , , , , ,
| | - Paul D Blischak
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA; , , , , ,
| | - Brittany L Sutherland
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA; , , , , ,
| | - Michael S Barker
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA; , , , , ,
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29
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Quezada-Martinez D, Addo Nyarko CP, Schiessl SV, Mason AS. Using wild relatives and related species to build climate resilience in Brassica crops. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2021; 134:1711-1728. [PMID: 33730183 PMCID: PMC8205867 DOI: 10.1007/s00122-021-03793-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 02/12/2021] [Indexed: 05/18/2023]
Abstract
Climate change will have major impacts on crop production: not just increasing drought and heat stress, but also increasing insect and disease loads and the chance of extreme weather events and further adverse conditions. Often, wild relatives show increased tolerances to biotic and abiotic stresses, due to reduced stringency of selection for yield and yield-related traits under optimum conditions. One possible strategy to improve resilience in our modern-day crop cultivars is to utilize wild relative germplasm in breeding, and attempt to introgress genetic factors contributing to greater environmental tolerances from these wild relatives into elite crop types. However, this approach can be difficult, as it relies on factors such as ease of hybridization and genetic distance between the source and target, crossover frequencies and distributions in the hybrid, and ability to select for desirable introgressions while minimizing linkage drag. In this review, we outline the possible effects that climate change may have on crop production, introduce the Brassica crop species and their wild relatives, and provide an index of useful traits that are known to be present in each of these species that may be exploitable through interspecific hybridization-based approaches. Subsequently, we outline how introgression breeding works, what factors affect the success of this approach, and how this approach can be optimized so as to increase the chance of recovering the desired introgression lines. Our review provides a working guide to the use of wild relatives and related crop germplasm to improve biotic and abiotic resistances in Brassica crop species.
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Affiliation(s)
- Daniela Quezada-Martinez
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Charles P Addo Nyarko
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Sarah V Schiessl
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
| | - Annaliese S Mason
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany.
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany.
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30
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Quezada-Martinez D, Addo Nyarko CP, Schiessl SV, Mason AS. Using wild relatives and related species to build climate resilience in Brassica crops. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2021; 134:1711-1728. [PMID: 33730183 DOI: 10.1007/s00122-021-03793-3.pdf] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 02/12/2021] [Indexed: 05/24/2023]
Abstract
Climate change will have major impacts on crop production: not just increasing drought and heat stress, but also increasing insect and disease loads and the chance of extreme weather events and further adverse conditions. Often, wild relatives show increased tolerances to biotic and abiotic stresses, due to reduced stringency of selection for yield and yield-related traits under optimum conditions. One possible strategy to improve resilience in our modern-day crop cultivars is to utilize wild relative germplasm in breeding, and attempt to introgress genetic factors contributing to greater environmental tolerances from these wild relatives into elite crop types. However, this approach can be difficult, as it relies on factors such as ease of hybridization and genetic distance between the source and target, crossover frequencies and distributions in the hybrid, and ability to select for desirable introgressions while minimizing linkage drag. In this review, we outline the possible effects that climate change may have on crop production, introduce the Brassica crop species and their wild relatives, and provide an index of useful traits that are known to be present in each of these species that may be exploitable through interspecific hybridization-based approaches. Subsequently, we outline how introgression breeding works, what factors affect the success of this approach, and how this approach can be optimized so as to increase the chance of recovering the desired introgression lines. Our review provides a working guide to the use of wild relatives and related crop germplasm to improve biotic and abiotic resistances in Brassica crop species.
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Affiliation(s)
- Daniela Quezada-Martinez
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Charles P Addo Nyarko
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Sarah V Schiessl
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
| | - Annaliese S Mason
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany.
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany.
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Ferreira de Carvalho J, Stoeckel S, Eber F, Lodé-Taburel M, Gilet MM, Trotoux G, Morice J, Falentin C, Chèvre AM, Rousseau-Gueutin M. Untangling structural factors driving genome stabilization in nascent Brassica napus allopolyploids. THE NEW PHYTOLOGIST 2021; 230:2072-2084. [PMID: 33638877 DOI: 10.1111/nph.17308] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 02/22/2021] [Indexed: 05/28/2023]
Abstract
Allopolyploids have globally higher fitness than their diploid progenitors; however, by comparison, most resynthesized allopolyploids have poor fertility and highly unstable genome. Elucidating the evolutionary processes promoting genome stabilization and fertility is thus essential to comprehend allopolyploid success. Using the Brassica model, we mimicked the speciation process of a nascent allopolyploid species by resynthesizing allotetraploid Brassica napus and systematically selecting for euploid individuals over eight generations in four independent allopolyploidization events with contrasted genetic backgrounds, cytoplasmic donors, and polyploid formation type. We evaluated the evolution of meiotic behavior and fertility and identified rearrangements in S1 to S9 lineages to explore the positive consequences of euploid selection on B. napus genome stability. Recurrent selection of euploid plants for eight generations drastically reduced the percentage of aneuploid progenies as early as the fourth generation, concomitantly with a decrease in number of newly fixed homoeologous rearrangements. The consequences of homoeologous rearrangements on meiotic behavior and seed number depended strongly on the genetic background and cytoplasm donor. The combined use of both self-fertilization and recurrent euploid selection allowed identification of genomic regions associated with fertility and meiotic behavior, providing complementary evidence to explain B. napus speciation success.
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Affiliation(s)
| | - Solenn Stoeckel
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, 35650, France
| | - Frédérique Eber
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, 35650, France
| | | | | | - Gwenn Trotoux
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, 35650, France
| | - Jérôme Morice
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, 35650, France
| | - Cyril Falentin
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, 35650, France
| | - Anne-Marie Chèvre
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, 35650, France
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Alabdullah AK, Moore G, Martín AC. A Duplicated Copy of the Meiotic Gene ZIP4 Preserves up to 50% Pollen Viability and Grain Number in Polyploid Wheat. BIOLOGY 2021; 10:290. [PMID: 33918149 PMCID: PMC8065865 DOI: 10.3390/biology10040290] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 12/20/2022]
Abstract
Although most flowering plants are polyploid, little is known of how the meiotic process evolves after polyploidisation to stabilise and preserve fertility. On wheat polyploidisation, the major meiotic gene ZIP4 on chromosome 3B duplicated onto 5B and diverged (TaZIP4-B2). TaZIP4-B2 was recently shown to promote homologous pairing, synapsis and crossover, and suppress homoeologous crossover. We therefore suspected that these meiotic stabilising effects could be important for preserving wheat fertility. A CRISPR Tazip4-B2 mutant was exploited to assess the contribution of the 5B duplicated ZIP4 copy in maintaining pollen viability and grain setting. Analysis demonstrated abnormalities in 56% of meiocytes in the Tazip4-B2 mutant, with micronuclei in 50% of tetrads, reduced size in 48% of pollen grains and a near 50% reduction in grain number. Further studies showed that most of the reduced grain number occurred when Tazip4-B2 mutant plants were pollinated with the less viable Tazip4-B2 mutant pollen rather than with wild type pollen, suggesting that the stabilising effect of TaZIP4-B2 on meiosis has a greater consequence in subsequent male, rather than female gametogenesis. These studies reveal the extraordinary value of the wheat chromosome 5B TaZIP4-B2 duplication to agriculture and human nutrition. Future studies should further investigate the role of TaZIP4-B2 on female fertility and assess whether different TaZIP4-B2 alleles exhibit variable effects on meiotic stabilisation and/or resistance to temperature change.
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Affiliation(s)
| | - Graham Moore
- Crop Genetics Department, John Innes Centre, Colney, Norwich NR4 7UH, UK; (A.K.A.); (A.C.M.)
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33
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Higgins EE, Howell EC, Armstrong SJ, Parkin IAP. A major quantitative trait locus on chromosome A9, BnaPh1, controls homoeologous recombination in Brassica napus. THE NEW PHYTOLOGIST 2021; 229:3281-3293. [PMID: 33020949 PMCID: PMC7984352 DOI: 10.1111/nph.16986] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/23/2020] [Indexed: 05/09/2023]
Abstract
Ensuring faithful homologous recombination in allopolyploids is essential to maintain optimal fertility of the species. Variation in the ability to control aberrant pairing between homoeologous chromosomes in Brassica napus has been identified. The current study exploited the extremes of such variation to identify genetic factors that differentiate newly resynthesised B. napus, which is inherently unstable, and established B. napus, which has adapted to largely control homoeologous recombination. A segregating B. napus mapping population was analysed utilising both cytogenetic observations and high-throughput genotyping to quantify the levels of homoeologous recombination. Three quantitative trait loci (QTL) were identified that contributed to the control of homoeologous recombination in the important oilseed crop B. napus. One major QTL on BnaA9 contributed between 32 and 58% of the observed variation. This study is the first to assess homoeologous recombination and map associated QTLs resulting from deviations in normal pairing in allotetraploid B. napus. The identified QTL regions suggest candidate meiotic genes that could be manipulated in order to control this important trait and further allow the development of molecular markers to utilise this trait to exploit homoeologous recombination in a crop.
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Affiliation(s)
- Erin E. Higgins
- Agriculture and Agri‐Food Canada107 Science PlaceSaskatoonSKS7N 0X2Canada
| | - Elaine C. Howell
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Susan J. Armstrong
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
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Wu Y, Lin F, Zhou Y, Wang J, Sun S, Wang B, Zhang Z, Li G, Lin X, Wang X, Sun Y, Dong Q, Xu C, Gong L, Wendel JF, Zhang Z, Liu B. Genomic mosaicism due to homoeologous exchange generates extensive phenotypic diversity in nascent allopolyploids. Natl Sci Rev 2020; 8:nwaa277. [PMID: 34691642 PMCID: PMC8288387 DOI: 10.1093/nsr/nwaa277] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 11/01/2020] [Indexed: 01/03/2023] Open
Abstract
Allopolyploidy is an important process in plant speciation, yet newly formed allopolyploid species typically suffer from extreme genetic bottlenecks. One escape from this impasse might be homoeologous meiotic pairing, during which homoeologous exchanges (HEs) generate phenotypically variable progeny. However, the immediate genome-wide patterns and resulting phenotypic diversity generated by HEs remain largely unknown. Here, we analyzed the genome composition of 202 phenotyped euploid segmental allopolyploid individuals from the fourth selfed generation following chromosomal doubling of reciprocal F1 hybrids of crosses between rice subspecies, using whole-genome sequencing. We describe rampant occurrence of HEs that, by overcoming incompatibility or conferring superiority of hetero-cytonuclear interactions, generate extensive and individualized genomic mosaicism across the analyzed tetraploids. We show that the resulting homoeolog copy number alteration in tetraploids affects known-function genes and their complex genetic interactions, in the process creating extraordinary phenotypic diversity at the population level following a single initial hybridization. Our results illuminate the immediate genomic landscapes possible in a tetraploid genomic environment, and underscore HE as an important mechanism that fuels rapid phenotypic diversification accompanying the initial stages of allopolyploid evolution.
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Affiliation(s)
- Ying Wu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
- Department of Crop & Soil Sciences, Washington State University, Pullman, WA 99164, USA
| | - Fan Lin
- Brightseed Inc., San Francisco, CA 94107, USA
| | - Yao Zhou
- Department of Crop & Soil Sciences, Washington State University, Pullman, WA 99164, USA
| | - Jie Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Shuai Sun
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Bin Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Zhibin Zhang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Guo Li
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Xiuyun Lin
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Xutong Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Yue Sun
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Qianli Dong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Chunming Xu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
| | - Lei Gong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
- Department of Ecology, Evolution & Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Jonathan F Wendel
- Department of Ecology, Evolution & Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Zhiwu Zhang
- Department of Crop & Soil Sciences, Washington State University, Pullman, WA 99164, USA
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China
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Seear PJ, France MG, Gregory CL, Heavens D, Schmickl R, Yant L, Higgins JD. A novel allele of ASY3 is associated with greater meiotic stability in autotetraploid Arabidopsis lyrata. PLoS Genet 2020; 16:e1008900. [PMID: 32667955 PMCID: PMC7392332 DOI: 10.1371/journal.pgen.1008900] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 07/30/2020] [Accepted: 06/01/2020] [Indexed: 01/09/2023] Open
Abstract
In this study we performed a genotype-phenotype association analysis of meiotic stability in 10 autotetraploid Arabidopsis lyrata and A. lyrata/A. arenosa hybrid populations collected from the Wachau region and East Austrian Forealps. The aim was to determine the effect of eight meiosis genes under extreme selection upon adaptation to whole genome duplication. Individual plants were genotyped by high-throughput sequencing of the eight meiosis genes (ASY1, ASY3, PDS5b, PRD3, REC8, SMC3, ZYP1a/b) implicated in synaptonemal complex formation and phenotyped by assessing meiotic metaphase I chromosome configurations. Our results reveal that meiotic stability varied greatly (20-100%) between individual tetraploid plants and associated with segregation of a novel ASYNAPSIS3 (ASY3) allele derived from A. lyrata. The ASY3 allele that associates with meiotic stability possesses a putative in-frame tandem duplication (TD) of a serine-rich region upstream of the coiled-coil domain that appears to have arisen at sites of DNA microhomology. The frequency of multivalents observed in plants homozygous for the ASY3 TD haplotype was significantly lower than in plants heterozygous for ASY3 TD/ND (non-duplicated) haplotypes. The chiasma distribution was significantly altered in the stable plants compared to the unstable plants with a shift from proximal and interstitial to predominantly distal locations. The number of HEI10 foci at pachytene that mark class I crossovers was significantly reduced in a plant homozygous for ASY3 TD compared to a plant heterozygous for ASY3 ND/TD. Fifty-eight alleles of the 8 meiosis genes were identified from the 10 populations analysed, demonstrating dynamic population variability at these loci. Widespread chimerism between alleles originating from A. lyrata/A. arenosa and diploid/tetraploids indicates that this group of rapidly evolving genes may provide precise adaptive control over meiotic recombination in the tetraploids, the very process that gave rise to them.
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Affiliation(s)
- Paul J. Seear
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Martin G. France
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Catherine L. Gregory
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Darren Heavens
- Earlham Institute, Norwich Research Park Innovation Centre, Norwich, United Kingdom
| | - Roswitha Schmickl
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
- Institute of Botany, The Czech Academy of Sciences, Průhonice, Czech Republic
| | - Levi Yant
- Future Food Beacon of Excellence and the School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
- * E-mail: (LY); (JDH)
| | - James D. Higgins
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
- * E-mail: (LY); (JDH)
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Homoeologous exchanges occur through intragenic recombination generating novel transcripts and proteins in wheat and other polyploids. Proc Natl Acad Sci U S A 2020; 117:14561-14571. [PMID: 32518116 DOI: 10.1073/pnas.2003505117] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recombination between homeologous chromosomes, also known as homeologous exchange (HE), plays a significant role in shaping genome structure and gene expression in interspecific hybrids and allopolyploids of several plant species. However, the molecular mechanisms that govern HEs are not well understood. Here, we studied HE events in the progeny of a nascent allotetraploid (genome AADD) derived from two diploid progenitors of hexaploid bread wheat using cytological and whole-genome sequence analyses. In total, 37 HEs were identified and HE junctions were mapped precisely. HEs exhibit typical patterns of homologous recombination hotspots, being biased toward low-copy, subtelomeric regions of chromosome arms and showing association with known recombination hotspot motifs. But, strikingly, while homologous recombination preferentially takes place upstream and downstream of coding regions, HEs are highly enriched within gene bodies, giving rise to novel recombinant transcripts, which in turn are predicted to generate new protein fusion variants. To test whether this is a widespread phenomenon, a dataset of high-resolution HE junctions was analyzed for allopolyploid Brassica, rice, Arabidopsis suecica, banana, and peanut. Intragenic recombination and formation of chimeric genes was detected in HEs of all species and was prominent in most of them. HE thus provides a mechanism for evolutionary novelty in transcript and protein sequences in nascent allopolyploids.
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Yang Y, Yan G, Li Z, Yuan J, Wei X, Wei F, Tian B, Xie Z, Shi G, Zhang X, Cao G. Cytological atlas at meiosis reveals insights into pollen fertility in synthetic Brassica allotriploids between allotetraploid B. carinata and diploid B. rapa. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 148:237-245. [PMID: 31981876 DOI: 10.1016/j.plaphy.2020.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 12/16/2019] [Accepted: 01/03/2020] [Indexed: 06/10/2023]
Abstract
The formation of allopolyploid crops basically depends on the successful interspecific hybridization and polyploidization, which generally involves in a combination of distinct but related genomes from independent species. But cytological analysis of these initially synthesized allohaploids immediately after genome merging is poorly explored in regards to anther and pollen development to date. In this study, Brassica trigenomic allohaploids (ABC) were produced to investigate the immediate effects of the genome combinations on pollen fertility during anther development via crosses between natural allotetraploid B. carinata (BBCC) and diploid B. rapa (AA). The results showed that in the synthetic Brassica allotriploids (ABC), the anther development was completely disrupted, and the pollen grains were mostly inviable with varied genetic complements. In addition, the meiosis course was aberrantly altered and eccentric chromosomal configurations including multivalent, bridges and lags occurred frequently during metaphase I to anaphase II. Genomic in situ hybridization (GISH) further revealed that B genome of homoeology was frequently apt to interact with A and C genomes, and cytoskeletal organizations was improperly distributed during meiosis in these synthetic Brassica allotriploids. Furthermore, we also confirmed that the expression of typical meiosis-related genes was obviously repressed during anther development in these Brassica allotriploids. Taken together, our results provide a detailed cytology for insights into pollen development in the synthetic allotriploid hybrids, which are conventionally considered as a useful genetic resource for polyploid Brassica breeding.
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Affiliation(s)
- Yan Yang
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China; School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Ge Yan
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Zishuang Li
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Jiachen Yuan
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Xiaochun Wei
- Institute of Horticultural Research, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, China
| | - Fang Wei
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China; School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China.
| | - Baoming Tian
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Zhengqing Xie
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Gongyao Shi
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China; School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Xiaowei Zhang
- Institute of Horticultural Research, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, China
| | - Gangqiang Cao
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, 450001, China.
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38
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Gaebelein R, Schiessl SV, Samans B, Batley J, Mason AS. Inherited allelic variants and novel karyotype changes influence fertility and genome stability in Brassica allohexaploids. THE NEW PHYTOLOGIST 2019; 223:965-978. [PMID: 30887525 DOI: 10.1111/nph.15804] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 03/13/2019] [Indexed: 05/22/2023]
Abstract
Synthetic allohexaploid Brassica hybrids (2n = AABBCC) do not exist naturally, but can be synthesized by crosses between diploid and/or allotetraploid Brassica species. Using these hybrids, we aimed to identify how novel allohexaploids restore fertility and normal meiosis after formation. Chromosome inheritance, genome structure, fertility and meiotic behaviour were assessed in three segregating allohexaploid populations derived from the cross (B. napus × B. carinata) × B. juncea using a combination of molecular marker genotyping, phenotyping and cytogenetics. Plants with unbalanced A-C translocations in one direction (where a C-genome chromosome fragment replaces an A-genome fragment) but not the other (where an A-genome fragment replaces a C-genome fragment) showed significantly reduced fertility across all populations. Genomic regions associated with fertility contained several meiosis genes with putatively causal mutations inherited from the parents (copies of SCC2 in the A genome, PAIR1/PRD3, PRD1 and ATK1/KATA/KIN14a in the B genome, and MSH2 and SMC1/TITAN8 in the C genome). Reduced seed fertility associated with the loss of chromosome fragments from only one subgenome following homoeologous exchanges could comprise a mechanism for biased genome fractionation in allopolyploids. Pre-existing meiosis gene variants present in allotetraploid parents may help to stabilize meiosis in novel allohexaploids.
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Affiliation(s)
- Roman Gaebelein
- Department of Plant Breeding, Justus Liebig University, Heinrich-Buff-Ring 26-32, Giessen, 35392, Germany
| | - Sarah V Schiessl
- Department of Plant Breeding, Justus Liebig University, Heinrich-Buff-Ring 26-32, Giessen, 35392, Germany
| | - Birgit Samans
- Faculty of Health Science, Technische Hochschule Mittelhessen, Wiesenstrasse 14, Giessen, 35390, Germany
| | - Jacqueline Batley
- School of Biological Sciences and Institute of Agriculture, University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
| | - Annaliese S Mason
- Department of Plant Breeding, Justus Liebig University, Heinrich-Buff-Ring 26-32, Giessen, 35392, Germany
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39
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Gonzalo A, Lucas MO, Charpentier C, Sandmann G, Lloyd A, Jenczewski E. Reducing MSH4 copy number prevents meiotic crossovers between non-homologous chromosomes in Brassica napus. Nat Commun 2019; 10:2354. [PMID: 31142748 PMCID: PMC6541637 DOI: 10.1038/s41467-019-10010-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 04/11/2019] [Indexed: 02/06/2023] Open
Abstract
In allopolyploids, correct chromosome segregation requires suppression of non-homologous crossovers while levels of homologous crossovers are ensured. To date, no mechanism able to specifically inhibit non-homologous crossovers has been described in allopolyploids other than in bread wheat. Here, we show that reducing the number of functional copies of MSH4, an essential gene for the main crossover pathway, prevents non-homologous crossovers in allotetraploid Brassica napus. We show that non-homologous crossovers originate almost exclusively from the MSH4-dependent recombination pathway and that their numbers decrease when MSH4 returns to single copy in B. napus; by contrast, homologous crossovers remain unaffected by MSH4 duplicate loss. We also demonstrate that MSH4 systematically returns to single copy following numerous independent polyploidy events, a pattern that is probably not by chance. These results suggest that stabilization of allopolyploid meiosis can be enhanced by loss of a key meiotic recombination gene.
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Affiliation(s)
- Adrián Gonzalo
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France.,Department of Cell and Developmental Biology, John Innes Centre, Norwich, NR4 7UH, UK
| | - Marie-Odile Lucas
- INRA UMR1349 Institut de Génétique, Environnement et Protection des Plantes, Le Rheu, 35653, France
| | - Catherine Charpentier
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Greta Sandmann
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Andrew Lloyd
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France.,Institute of Biological, Environmental, and Rural Sciences, Aberystwyth University, Aberystwyth, SY23 3EB, UK
| | - Eric Jenczewski
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France.
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40
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Higgins EE, Clarke WE, Howell EC, Armstrong SJ, Parkin IAP. Detecting de Novo Homoeologous Recombination Events in Cultivated Brassica napus Using a Genome-Wide SNP Array. G3 (BETHESDA, MD.) 2018; 8:2673-2683. [PMID: 29907649 PMCID: PMC6071606 DOI: 10.1534/g3.118.200118] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 06/12/2018] [Indexed: 11/20/2022]
Abstract
The heavy selection pressure due to intensive breeding of Brassica napus has created a narrow gene pool, limiting the ability to produce improved varieties through crosses between B. napus cultivars. One mechanism that has contributed to the adaptation of important agronomic traits in the allotetraploid B. napus has been chromosomal rearrangements resulting from homoeologous recombination between the constituent A and C diploid genomes. Determining the rate and distribution of such events in natural B. napus will assist efforts to understand and potentially manipulate this phenomenon. The Brassica high-density 60K SNP array, which provides genome-wide coverage for assessment of recombination events, was used to assay 254 individuals derived from 11 diverse cultivated spring type B. napus These analyses identified reciprocal allele gain and loss between the A and C genomes and allowed visualization of de novo homoeologous recombination events across the B. napus genome. The events ranged from loss/gain of 0.09 Mb to entire chromosomes, with almost 5% aneuploidy observed across all gametes. There was a bias toward sub-telomeric exchanges leading to genome homogenization at chromosome termini. The A genome replaced the C genome in 66% of events, and also featured more dominantly in gain of whole chromosomes. These analyses indicate de novo homoeologous recombination is a continuous source of variation in established Brassica napus and the rate of observed events appears to vary with genetic background. The Brassica 60K SNP array will be a useful tool in further study and manipulation of this phenomenon.
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Affiliation(s)
- Erin E Higgins
- Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK, S7N 0X2, Canada
| | - Wayne E Clarke
- Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK, S7N 0X2, Canada
| | - Elaine C Howell
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Susan J Armstrong
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Isobel A P Parkin
- Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK, S7N 0X2, Canada
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Qi P, Gimode D, Saha D, Schröder S, Chakraborty D, Wang X, Dida MM, Malmberg RL, Devos KM. UGbS-Flex, a novel bioinformatics pipeline for imputation-free SNP discovery in polyploids without a reference genome: finger millet as a case study. BMC PLANT BIOLOGY 2018; 18:117. [PMID: 29902967 PMCID: PMC6003085 DOI: 10.1186/s12870-018-1316-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 05/23/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND Research on orphan crops is often hindered by a lack of genomic resources. With the advent of affordable sequencing technologies, genotyping an entire genome or, for large-genome species, a representative fraction of the genome has become feasible for any crop. Nevertheless, most genotyping-by-sequencing (GBS) methods are geared towards obtaining large numbers of markers at low sequence depth, which excludes their application in heterozygous individuals. Furthermore, bioinformatics pipelines often lack the flexibility to deal with paired-end reads or to be applied in polyploid species. RESULTS UGbS-Flex combines publicly available software with in-house python and perl scripts to efficiently call SNPs from genotyping-by-sequencing reads irrespective of the species' ploidy level, breeding system and availability of a reference genome. Noteworthy features of the UGbS-Flex pipeline are an ability to use paired-end reads as input, an effective approach to cluster reads across samples with enhanced outputs, and maximization of SNP calling. We demonstrate use of the pipeline for the identification of several thousand high-confidence SNPs with high representation across samples in an F3-derived F2 population in the allotetraploid finger millet. Robust high-density genetic maps were constructed using the time-tested mapping program MAPMAKER which we upgraded to run efficiently and in a semi-automated manner in a Windows Command Prompt Environment. We exploited comparative GBS with one of the diploid ancestors of finger millet to assign linkage groups to subgenomes and demonstrate the presence of chromosomal rearrangements. CONCLUSIONS The paper combines GBS protocol modifications, a novel flexible GBS analysis pipeline, UGbS-Flex, recommendations to maximize SNP identification, updated genetic mapping software, and the first high-density maps of finger millet. The modules used in the UGbS-Flex pipeline and for genetic mapping were applied to finger millet, an allotetraploid selfing species without a reference genome, as a case study. The UGbS-Flex modules, which can be run independently, are easily transferable to species with other breeding systems or ploidy levels.
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Affiliation(s)
- Peng Qi
- Institute of Plant Breeding, Genetics and Genomics (Department of Crop and Soil Sciences), University of Georgia, Athens, GA 30602 USA
- Department of Plant Biology, University of Georgia, Athens, GA 30602 USA
| | - Davis Gimode
- Institute of Plant Breeding, Genetics and Genomics (Department of Crop and Soil Sciences), University of Georgia, Athens, GA 30602 USA
- ICRISAT-Nairobi, P.O. Box 39063-00623, Nairobi, Kenya
- Present address: Institute of Plant Breeding, Genetics and Genomics (Department of Horticulture), Tifton, GA 31793 USA
| | - Dipnarayan Saha
- Institute of Plant Breeding, Genetics and Genomics (Department of Crop and Soil Sciences), University of Georgia, Athens, GA 30602 USA
- Department of Plant Biology, University of Georgia, Athens, GA 30602 USA
- Present address: ICAR-Central Research Institute for Jute and Allied Fibres, Kolkata, India
| | - Stephan Schröder
- Institute of Plant Breeding, Genetics and Genomics (Department of Crop and Soil Sciences), University of Georgia, Athens, GA 30602 USA
- Department of Plant Biology, University of Georgia, Athens, GA 30602 USA
- Present address: Department of Plant Sciences, North Dakota State University, Fargo, ND 58108 USA
| | | | - Xuewen Wang
- Department of Genetics, University of Georgia, Athens, GA 30602 USA
| | - Mathews M. Dida
- Department of Applied Plant Sciences, Maseno University, Maseno, Kenya
| | | | - Katrien M. Devos
- Institute of Plant Breeding, Genetics and Genomics (Department of Crop and Soil Sciences), University of Georgia, Athens, GA 30602 USA
- Department of Plant Biology, University of Georgia, Athens, GA 30602 USA
- Institute of Bioinformatics, University of Georgia, Athens, GA 30602 USA
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42
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Vieira MLC, Almeida CB, Oliveira CA, Tacuatiá LO, Munhoz CF, Cauz-Santos LA, Pinto LR, Monteiro-Vitorello CB, Xavier MA, Forni-Martins ER. Revisiting Meiosis in Sugarcane: Chromosomal Irregularities and the Prevalence of Bivalent Configurations. Front Genet 2018; 9:213. [PMID: 29963076 PMCID: PMC6010537 DOI: 10.3389/fgene.2018.00213] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Accepted: 05/25/2018] [Indexed: 12/01/2022] Open
Abstract
Traditional sugarcane cultivars (Saccharum officinarum) proved highly susceptible to diseases, and this led breeders to progress to interspecific crosses resulting in disease resistance. A backcrossing program to S. officinarum was then required to boost sucrose content. Clonal selection across generations and incorporation of other germplasm into cultivated backgrounds established the (narrow) genetic base of modern cultivars (Saccharum spp.), which have a man-made genome. The genome complexity has inspired several molecular studies that have elucidated aspects of sugarcane genome constitution, architecture, and cytogenetics. However, there is a critical shortage of information on chromosome behavior throughout meiosis in modern cultivars. In this study, we examined the microsporogenesis of a contemporary variety, providing a detailed analysis of the meiotic process and chromosome association at diakinesis, using FISH with centromeric probes. Chromosomal abnormalities were documented by examining high quality preparations of pollen mother cells (700 in total). Approximately 70% of the cells showed abnormalities, such as metaphase chromosomes not lined up at the plate, lagging chromosomes and chromosomal bridges, and tetrad cells with micronuclei. Some dyads with asynchronous behavior were also observed. Due to the hybrid composition of the sugarcane genome, we suggest that bivalent incomplete pairing may occur in the first prophase leading to univalency. The presence of rod bivalents showing the lagging tendency is consistent with a reduction in chiasma frequency. Finally, the presence of chromatin bridges indicates the indirect occurrence of chromosomal inversions, although chromosome fragments were not clearly recognized. Possible reasons for such meiotic abnormalities and the large prevalence of bivalent formation are discussed.
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Affiliation(s)
- Maria Lucia C Vieira
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, Brazil
| | - Carmelice B Almeida
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, Brazil
| | - Carlos A Oliveira
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, Brazil
| | - Luana O Tacuatiá
- Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
| | - Carla F Munhoz
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, Brazil
| | - Luiz A Cauz-Santos
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, Brazil
| | - Luciana R Pinto
- Centro de Cana, Instituto Agronômico de Campinas, Ribeirão Preto, Brazil
| | | | - Mauro A Xavier
- Centro de Cana, Instituto Agronômico de Campinas, Ribeirão Preto, Brazil
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43
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Rouiss H, Bakry F, Froelicher Y, Navarro L, Aleza P, Ollitrault P. Origin of C. latifolia and C. aurantiifolia triploid limes: the preferential disomic inheritance of doubled-diploid 'Mexican' lime is consistent with an interploid hybridization hypothesis. ANNALS OF BOTANY 2018; 121:571-585. [PMID: 29293884 PMCID: PMC5838810 DOI: 10.1093/aob/mcx179] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 11/14/2017] [Indexed: 05/23/2023]
Abstract
Background and Aims Two main types of triploid limes are produced worldwide. The 'Tahiti' lime type (Citrus latifolia) is predominant, while the 'Tanepao' type (C. aurantiifolia) is produced to a lesser extent. Both types result from natural interspecific hybridization involving a diploid gamete of C. aurantiifolia 'Mexican' lime type (itself a direct interspecific C. micrantha × C. medica hybrid). The meiotic behaviour of a doubled-diploid 'Mexican' lime, the interspecific micrantha/medica recombination and the resulting diploid gamete structures were analysed to investigate the possibility that 'Tahiti' and 'Tanepao' varieties are derived from natural interploid hybridization. Methods A population of 85 tetraploid hybrids was established between a doubled-diploid clementine and a doubled-diploid 'Mexican' lime and used to infer the genotypes of 'Mexican' lime diploid gametes. Meiotic behaviour was studied through combined segregation analysis of 35 simple sequenbce repeat (SSR) and single nucleotide polymorphismn (SNP) markers covering the nine citrus chromosomes and cytogenetic studies. It was supplemented by pollen viability assessment. Key Results Pollen viability of the doubled-diploid Mexican lime (64 %) was much higher than that of the diploid. On average, 65 % of the chromosomes paired as bivalents and 31.4 % as tetravalents. Parental heterozygosity restitution ranged from 83 to 99 %. Disomic inheritance with high preferential pairing values was deduced for three chromosomes. Intermediate inheritances, with disomic trend, were found for five chromosomes, and an intermediate inheritance was observed for one chromosome. The average effective interspecific recombination rate was low (1.2 cM Mb-1). Conclusion The doubled-diploid 'Mexican' lime had predominantly disomic segregation, producing interspecific diploid gamete structures with high C. medica/C. micrantha heterozygosity, compatible with the phylogenomic structures of triploid C. latifolia and C. aurantiifolia varieties. This disomic trend limits effective interspecific recombination and diversity of the diploid gamete population. Interploid reconstruction breeding using doubled-diploid lime as one parent is a promising approach for triploid lime diversification.
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Affiliation(s)
- H Rouiss
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
- Unité Mixte de Recherche Amélioration Génétique et Adaptation des Plantes (UMR Agap), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Petit-Bourg, Guadeloupe, France
| | - F Bakry
- Unité Mixte de Recherche Amélioration Génétique et Adaptation des Plantes (UMR Agap), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Montpellier, France
| | - Y Froelicher
- Unité Mixte de Recherche Amélioration Génétique et Adaptation des Plantes (UMR Agap), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), San Giuliano, Corse, France
| | - L Navarro
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - P Aleza
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - P Ollitrault
- Unité Mixte de Recherche Amélioration Génétique et Adaptation des Plantes (UMR Agap), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Petit-Bourg, Guadeloupe, France
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Poggio L, González GE. Cytological diploidization of paleopolyploid genus Zea: Divergence between homoeologous chromosomes or activity of pairing regulator genes? PLoS One 2018; 13:e0189644. [PMID: 29293518 PMCID: PMC5749740 DOI: 10.1371/journal.pone.0189644] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/29/2017] [Indexed: 11/18/2022] Open
Abstract
Cytological diploidization process is different in autopolyploid and allopolyploid species. Colchicine applied at the onset of meiosis suppresses the effect of pairing regulator genes resulting multivalents formation in bivalent-forming species. Colchicine treated maizes (4x = 2n = 20, AmAmBmBm) showed up to 5IV, suggesting pairing between chromosomes from genomes homoeologous Am and Bm. In untreated individuals of the alloautooctoploid Zea perennis (8x = 2n = 40, ApApAp´Ap´Bp1Bp1Bp2Bp2) the most frequent configuration was 5IV+10II (formed by A and B genomes, respectively). The colchicine treated Z. perennis show up to 10IV revealing higher affinity within genomes A and B, but any homology among them. These results suggest the presence of a paring regulator locus (PrZ) in maize and Z. perennis, whose expression is suppressed by colchicine. It could be postulated that in Z. perennis, PrZ would affect independently the genomes A and B, being relevant the threshold of homology, the fidelity of pairing in each genomes and the ploidy level. Cytological analysis of the treated hexaploid hybrids (6x = 2n = 30), with Z. perennis as a parental, strongly suggests that PrZ is less effective in only one doses. This conclusion was reinforced by the homoeologous pairing observed in untreated dihaploid maizes, which showed up to 5II. Meiotic behaviour of individuals treated with different doses of colchicine allowed to postulate that PrZ affect the homoeologous association by controlling entire genomes (Am or Bm) rather than individual chromosomes. Based on cytological and statistical results it is possible to propose that the cytological diploidization in Zea species occurs by restriction of pairing between homoeologous chromosomes or by genetical divergence of the homoeologous chromosomes, as was observed in untreated Z. mays ssp. parviglumis. These are independent but complementary systems and could be acting jointly in the same nucleus.
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Affiliation(s)
- Lidia Poggio
- Instituto de Ecología, Genética y Evolución (IEGEBA, Consejo Nacional de Investigaciones Científicas y Técnicas—CONICET)—Laboratorio de Citogenética y Evolución (LaCyE), Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Graciela Esther González
- Instituto de Ecología, Genética y Evolución (IEGEBA, Consejo Nacional de Investigaciones Científicas y Técnicas—CONICET)—Laboratorio de Citogenética y Evolución (LaCyE), Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
- * E-mail:
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Blary A, Gonzalo A, Eber F, Bérard A, Bergès H, Bessoltane N, Charif D, Charpentier C, Cromer L, Fourment J, Genevriez C, Le Paslier MC, Lodé M, Lucas MO, Nesi N, Lloyd A, Chèvre AM, Jenczewski E. FANCM Limits Meiotic Crossovers in Brassica Crops. FRONTIERS IN PLANT SCIENCE 2018; 9:368. [PMID: 29628933 PMCID: PMC5876677 DOI: 10.3389/fpls.2018.00368] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/06/2018] [Indexed: 05/18/2023]
Abstract
Meiotic crossovers (COs) are essential for proper chromosome segregation and the reshuffling of alleles during meiosis. In WT plants, the number of COs is usually small, which limits the genetic variation that can be captured by plant breeding programs. Part of this limitation is imposed by proteins like FANCM, the inactivation of which results in a 3-fold increase in COs in Arabidopsis thaliana. Whether the same holds true in crops needed to be established. In this study, we identified EMS induced mutations in FANCM in two species of economic relevance within the genus Brassica. We showed that CO frequencies were increased in fancm mutants in both diploid and tetraploid Brassicas, Brassica rapa and Brassica napus respectively. In B. rapa, we observed a 3-fold increase in the number of COs, equal to the increase observed previously in Arabidopsis. In B. napus we observed a lesser but consistent increase (1.3-fold) in both euploid (AACC) and allohaploid (AC) plants. Complementation tests in A. thaliana suggest that the smaller increase in crossover frequency observed in B. napus reflects residual activity of the mutant C copy of FANCM. Altogether our results indicate that the anti-CO activity of FANCM is conserved across the Brassica, opening new avenues to make a wider range of genetic diversity accessible to crop improvement.
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Affiliation(s)
- Aurélien Blary
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Adrián Gonzalo
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Frédérique Eber
- IGEPP, Institut National de la Recherche Agronomique, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Aurélie Bérard
- EPGV US 1279, Institut National de la Recherche Agronomique, CEA-IG-CNG, Université Paris-Saclay, Evry, France
| | - Hélène Bergès
- Institut National de la Recherche Agronomique UPR 1258, Centre National des Ressources Génomiques Végétales, Castanet-Tolosan, France
| | - Nadia Bessoltane
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Delphine Charif
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Catherine Charpentier
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Laurence Cromer
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Joelle Fourment
- Institut National de la Recherche Agronomique UPR 1258, Centre National des Ressources Génomiques Végétales, Castanet-Tolosan, France
| | - Camille Genevriez
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Marie-Christine Le Paslier
- EPGV US 1279, Institut National de la Recherche Agronomique, CEA-IG-CNG, Université Paris-Saclay, Evry, France
| | - Maryse Lodé
- IGEPP, Institut National de la Recherche Agronomique, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Marie-Odile Lucas
- IGEPP, Institut National de la Recherche Agronomique, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Nathalie Nesi
- IGEPP, Institut National de la Recherche Agronomique, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Andrew Lloyd
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
| | - Anne-Marie Chèvre
- IGEPP, Institut National de la Recherche Agronomique, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Eric Jenczewski
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National De La Recherche Scientifique, Université Paris-Saclay, Versailles, France
- *Correspondence: Eric Jenczewski
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Homoeologous chromosome pairing across the eukaryote phylogeny. Mol Phylogenet Evol 2017; 117:83-94. [PMID: 28602622 DOI: 10.1016/j.ympev.2017.05.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 05/25/2017] [Accepted: 05/26/2017] [Indexed: 11/21/2022]
Abstract
During the past quarter century, molecular phylogenetic inferences have significantly resolved evolutionary relationships spanning the eukaryotic tree of life. With improved phylogenies in hand, the focus of systematics will continue to expand from estimating species relationships toward examining the evolution of specific, fundamental traits across the eukaryotic tree. Undoubtedly, this will expose knowledge gaps in the evolution of key traits, particularly with respect to non-model lineages. Here, we examine one such trait across eukaryotes-the regulation of homologous chromosome pairing during meiosis-as an illustrative example. Specifically, we present an overview of the breakdown of homologous chromosome pairing in model eukaryotes and provide a discussion of various meiotic aberrations that result in the failure of homolog recognition, with a particular focus on lineages with a history of hybridization and polyploidization, across major eukaryotic clades. We then explore what is known about these processes in natural and non-model eukaryotic taxa, thereby exposing disparities in our understanding of this key trait among non-model groups.
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Zhan Z, Nwafor CC, Hou Z, Gong J, Zhu B, Jiang Y, Zhou Y, Wu J, Piao Z, Tong Y, Liu C, Zhang C. Cytological and morphological analysis of hybrids between Brassicoraphanus, and Brassica napus for introgression of clubroot resistant trait into Brassica napus L. PLoS One 2017; 12:e0177470. [PMID: 28505203 PMCID: PMC5432170 DOI: 10.1371/journal.pone.0177470] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 04/27/2017] [Indexed: 11/29/2022] Open
Abstract
Interspecific hybridization is a powerful tool for improvement of crop species, it has the potential to broaden the genetic base and create new plant forms for breeding programs. Synthetic allopolyploid is a widely-used model for the study of genetic recombination and fixed heterosis in Brassica. In Brassica napus breeding, identification and introgression of new sources of clubroot resistance trait from wild or related species into it by hybridization is a long-term crop management strategy for clubroot disease. Radish (Raphanus sativus L.) is a close relative of the Brassica and most radish accessions are immune to the clubroot disease. A synthesized allotetraploid Brassicoraphanus (RRCC, 2n = 36) between R. sativus cv. HQ-04 (2n = 18, RR) and Brassica oleracea var. alboglabra (L.H Bailey) (2n = 18, CC) proved resistant of multiple clubroot disease pathogen P. brassicae. To predict the possibility to transfer the clubroot resistance trait from the RR subgenome of allotetraploid Brassicoraphanus (RRCC, 2n = 36) into Brassica napus (AACC, 2n = 38), we analyzed the frequency of chromosome pairings in the F1 hybrids produced from a cross between B. napus cv. HS5 and the allotetraploid, characterize the genomic composition of some backcrossed progeny (BC1) using GISH, BAC-FISH and AFLP techniques. The level of intergenomic pairing between A and R genomes in the F1 hybrid was high, allosyndetic bivalents formed in 73.53% PMCs indicative of significant level of homeologous recombination between two genomes and high probability of incorporating chromosomal segments/genes from R-genome into A/C-genomes. The BC1 plants inherited variant extra R chromosomes or fragments from allotetraploid as revealed by GISH and AFLP analysis. 13.51% BC2 individuals were resistant to clubroot disease, and several resistance lines had high pollen fertility, Overall, the genetic material presented in this work represents a potential new genetic resource for practical use in breeding B. napus clubroot resistant cultivars.
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Affiliation(s)
- Zongxiang Zhan
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Chinedu Charles Nwafor
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhaoke Hou
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jianfang Gong
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Bin Zhu
- College of Life Science, Guizhou Normal University, Guiyang, China
| | - Yingfen Jiang
- Crop Research Institute, Anhui Academy of Agricultural Sciences, Hefei, China
| | - Yongming Zhou
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jiangsheng Wu
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhongyun Piao
- Department of Horticulture, Shenyang Agricultural University, Shenyang, China
| | - Yue Tong
- Yichang Academy of Agriculture Science, Yichang, China
| | - Chao Liu
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Chunyu Zhang
- National Research Center of Rapeseed Engineering and Technology and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
- * E-mail:
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Pelé A, Falque M, Trotoux G, Eber F, Nègre S, Gilet M, Huteau V, Lodé M, Jousseaume T, Dechaumet S, Morice J, Poncet C, Coriton O, Martin OC, Rousseau-Gueutin M, Chèvre AM. Amplifying recombination genome-wide and reshaping crossover landscapes in Brassicas. PLoS Genet 2017; 13:e1006794. [PMID: 28493942 PMCID: PMC5444851 DOI: 10.1371/journal.pgen.1006794] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 05/25/2017] [Accepted: 05/02/2017] [Indexed: 11/19/2022] Open
Abstract
Meiotic recombination by crossovers (COs) is tightly regulated, limiting its key role in producing genetic diversity. However, while COs are usually restricted in number and not homogenously distributed along chromosomes, we show here how to disrupt these rules in Brassica species by using allotriploid hybrids (AAC, 2n = 3x = 29), resulting from the cross between the allotetraploid rapeseed (B. napus, AACC, 2n = 4x = 38) and one of its diploid progenitors (B. rapa, AA, 2n = 2x = 20). We produced mapping populations from different genotypes of both diploid AA and triploid AAC hybrids, used as female and/or as male. Each population revealed nearly 3,000 COs that we studied with SNP markers well distributed along the A genome (on average 1 SNP per 1.25 Mbp). Compared to the case of diploids, allotriploid hybrids showed 1.7 to 3.4 times more overall COs depending on the sex of meiosis and the genetic background. Most surprisingly, we found that such a rise was always associated with (i) dramatic changes in the shape of recombination landscapes and (ii) a strong decrease of CO interference. Hybrids carrying an additional C genome exhibited COs all along the A chromosomes, even in the vicinity of centromeres that are deprived of COs in diploids as well as in most studied species. Moreover, in male allotriploid hybrids we found that Class I COs are mostly responsible for the changes of CO rates, landscapes and interference. These results offer the opportunity for geneticists and plant breeders to dramatically enhance the generation of diversity in Brassica species by disrupting the linkage drag coming from limits on number and distribution of COs.
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Affiliation(s)
- Alexandre Pelé
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Matthieu Falque
- GQE-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif sur Yvette, France
| | - Gwenn Trotoux
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Frédérique Eber
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Sylvie Nègre
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Marie Gilet
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Virginie Huteau
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Maryse Lodé
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | | | - Sylvain Dechaumet
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Jérôme Morice
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | | | - Olivier Coriton
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Olivier C. Martin
- GQE-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif sur Yvette, France
| | | | - Anne-Marie Chèvre
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
- * E-mail:
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49
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Bourke PM, Arens P, Voorrips RE, Esselink GD, Koning-Boucoiran CFS, Van't Westende WPC, Santos Leonardo T, Wissink P, Zheng C, van Geest G, Visser RGF, Krens FA, Smulders MJM, Maliepaard C. Partial preferential chromosome pairing is genotype dependent in tetraploid rose. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 90:330-343. [PMID: 28142191 DOI: 10.1111/tpj.13496] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 05/18/2023]
Abstract
It has long been recognised that polyploid species do not always neatly fall into the categories of auto- or allopolyploid, leading to the term 'segmental allopolyploid' to describe everything in between. The meiotic behaviour of such intermediate species is not fully understood, nor is there consensus as to how to model their inheritance patterns. In this study we used a tetraploid cut rose (Rosa hybrida) population, genotyped using the 68K WagRhSNP array, to construct an ultra-high-density linkage map of all homologous chromosomes using methods previously developed for autotetraploids. Using the predicted bivalent configurations in this population we quantified differences in pairing behaviour among and along homologous chromosomes, leading us to correct our estimates of recombination frequency to account for this behaviour. This resulted in the re-mapping of 25 695 SNP markers across all homologues of the seven rose chromosomes, tailored to the pairing behaviour of each chromosome in each parent. We confirmed the inferred differences in pairing behaviour among chromosomes by examining repulsion-phase linkage estimates, which also carry information about preferential pairing and recombination. Currently, the closest sequenced relative to rose is Fragaria vesca. Aligning the integrated ultra-dense rose map with the strawberry genome sequence provided a detailed picture of the synteny, confirming overall co-linearity but also revealing new genomic rearrangements. Our results suggest that pairing affinities may vary along chromosome arms, which broadens our current understanding of segmental allopolyploidy.
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Affiliation(s)
- Peter M Bourke
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Paul Arens
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Roeland E Voorrips
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - G Danny Esselink
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | | | - Wendy P C Van't Westende
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Tiago Santos Leonardo
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Patrick Wissink
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Chaozhi Zheng
- Biometris, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Geert van Geest
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
- Horticulture and Product Physiology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Richard G F Visser
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Frans A Krens
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Marinus J M Smulders
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Chris Maliepaard
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
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50
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Lambing C, Franklin FCH, Wang CJR. Understanding and Manipulating Meiotic Recombination in Plants. PLANT PHYSIOLOGY 2017; 173:1530-1542. [PMID: 28108697 PMCID: PMC5338670 DOI: 10.1104/pp.16.01530] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 01/18/2017] [Indexed: 05/18/2023]
Abstract
Meiosis is a specialized cell division, essential in most reproducing organisms to halve the number of chromosomes, thereby enabling the restoration of ploidy levels during fertilization. A key step of meiosis is homologous recombination, which promotes homologous pairing and generates crossovers (COs) to connect homologous chromosomes until their separation at anaphase I. These CO sites, seen cytologically as chiasmata, represent a reciprocal exchange of genetic information between two homologous nonsister chromatids. This gene reshuffling during meiosis has a significant influence on evolution and also plays an essential role in plant breeding, because a successful breeding program depends on the ability to bring the desired combinations of alleles on chromosomes. However, the number and distribution of COs during meiosis is highly constrained. There is at least one CO per chromosome pair to ensure accurate segregation of homologs, but in most organisms, the CO number rarely exceeds three regardless of chromosome size. Moreover, their positions are not random on chromosomes but exhibit regional preference. Thus, genes in recombination-poor regions tend to be inherited together, hindering the generation of novel allelic combinations that could be exploited by breeding programs. Recently, much progress has been made in understanding meiotic recombination. In particular, many genes involved in the process in Arabidopsis (Arabidopsis thaliana) have been identified and analyzed. With the coming challenges of food security and climate change, and our enhanced knowledge of how COs are formed, the interest and needs in manipulating CO formation are greater than ever before. In this review, we focus on advances in understanding meiotic recombination and then summarize the attempts to manipulate CO formation. Last, we pay special attention to the meiotic recombination in polyploidy, which is a common genomic feature for many crop plants.
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Affiliation(s)
- Christophe Lambing
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (C.L.)
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom (F.C.H.F.); and
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529 Taiwan (C.-J.R.W.)
| | - F Chris H Franklin
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (C.L.)
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom (F.C.H.F.); and
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529 Taiwan (C.-J.R.W.)
| | - Chung-Ju Rachel Wang
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom (C.L.);
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom (F.C.H.F.); and
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529 Taiwan (C.-J.R.W.)
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