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Zhuravleva АА, Silkova ОG. Disomic chromosome 3R(3B) substitution causes a complex of meiotic abnormalities in bread wheat Triticum aestivum L. Vavilovskii Zhurnal Genet Selektsii 2024; 28:365-376. [PMID: 39027125 PMCID: PMC11253021 DOI: 10.18699/vjgb-24-42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 03/25/2024] [Accepted: 03/26/2024] [Indexed: 07/20/2024] Open
Abstract
Triticum aestivum L. lines introgressed with alien chromosomes create a new genetic background that changes the gene expression of both wheat and donor chromosomes. The genes involved in meiosis regulation are localized on wheat chromosome 3B. The purpose of the present study was to investigate the effect of wheat chromosome 3B substituted with homoeologous rye chromosome 3R on meiosis regulation in disomically substituted wheat line 3R(3B). Employing immunostaining with antibodies against microtubule protein, α-tubulin, and the centromere-specific histone (CENH3), as well as FISH, we analyzed microtubule cytoskeleton dynamics and wheat and rye 3R chromosomes behavior in 3R(3B) (Triticum aestivum L. variety Saratovskaya 29 × Secale cereale L. variety Onokhoiskaya) meiosis. The results revealed a set of abnormalities in the microtubule dynamics and chromosome behavior in both first and second divisions. A feature of metaphase I in 3R(3B) was a decrease in the chiasmata number compared with variety Saratovskaya 29, 34.9 ± 0.62 and 41.92 ± 0.38, respectively. Rye homologs 3R in 13.18 % of meiocytes did not form bivalents. Chromosomes were characterized by varying degrees of compaction; 53.33 ± 14.62 cells lacked a metaphase plate. Disturbances were found in microtubule nucleation at the bivalent kinetochores and in their convergence at the spindle division poles. An important feature of meiosis was the asynchronous chromosome behavior in the second division and dyads at the telophase II in 8-13 % of meiocytes, depending on the anther studied. Considering the 3R(3B) meiotic phenotype, chromosome 3B contains the genes involved in the regulation of meiotic division, and substituting 3B3B chromosomes with rye 3R3R does not compensate for their absence.
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Affiliation(s)
- А А Zhuravleva
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - О G Silkova
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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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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Di Dio C, Serra H, Sourdille P, Higgins JD. ASYNAPSIS 1 ensures crossover fidelity in polyploid wheat by promoting homologous recombination and suppressing non-homologous recombination. FRONTIERS IN PLANT SCIENCE 2023; 14:1188347. [PMID: 37284727 PMCID: PMC10239940 DOI: 10.3389/fpls.2023.1188347] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 04/17/2023] [Indexed: 06/08/2023]
Abstract
During meiosis, the chromosome axes and synaptonemal complex mediate chromosome pairing and homologous recombination to maintain genomic stability and accurate chromosome segregation. In plants, ASYNAPSIS 1 (ASY1) is a key component of the chromosome axis that promotes inter-homolog recombination, synapsis and crossover formation. Here, the function of ASY1 has been cytologically characterized in a series of hypomorphic wheat mutants. In tetraploid wheat, asy1 hypomorphic mutants experience a reduction in chiasmata (crossovers) in a dosage-specific manner, resulting in failure to maintain crossover (CO) assurance. In mutants with only one functional copy of ASY1, distal chiasmata are maintained at the expense of proximal and interstitial chiasmata, indicating that ASY1 is required to promote chiasma formation away from the chromosome ends. Meiotic prophase I progression is delayed in asy1 hypomorphic mutants and is arrested in asy1 null mutants. In both tetraploid and hexaploid wheat, single asy1 mutants exhibit a high degree of ectopic recombination between multiple chromosomes at metaphase I. To explore the nature of the ectopic recombination, Triticum turgidum asy1b-2 was crossed with wheat-wild relative Aegilops variabilis. Homoeologous chiasmata increased 3.75-fold in Ttasy1b-2/Ae. variabilis compared to wild type/Ae. variabilis, indicating that ASY1 suppresses chiasma formation between divergent, but related chromosomes. These data suggest that ASY1 promotes recombination along the chromosome arms of homologous chromosomes whilst suppressing recombination between non-homologous chromosomes. Therefore, asy1 mutants could be utilized to increase recombination between wheat wild relatives and elite varieties for expediting introgression of important agronomic traits.
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Affiliation(s)
- Chiara Di Dio
- Department of Genetics and Genome Biology, Adrian Building, University of Leicester, Leicester, United Kingdom
| | - Heïdi Serra
- Genetics, Diversity and Ecophysiology of Cereals, Unité Mixte de Recherche (UMR) 1095, The Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
| | - Pierre Sourdille
- Genetics, Diversity and Ecophysiology of Cereals, Unité Mixte de Recherche (UMR) 1095, The Institut National de la Recherche Agronomique (INRAE), Université Clermont Auvergne, Clermont-Ferrand, France
| | - James D. Higgins
- Department of Genetics and Genome Biology, Adrian Building, University of Leicester, Leicester, United Kingdom
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Prasad P, Khatoon U, Verma RK, Aalam S, Kumar A, Mohapatra D, Bhattacharya P, Bag SK, Sawant SV. Transcriptional Landscape of Cotton Fiber Development and Its Alliance With Fiber-Associated Traits. FRONTIERS IN PLANT SCIENCE 2022; 13:811655. [PMID: 35283936 PMCID: PMC8908376 DOI: 10.3389/fpls.2022.811655] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 01/10/2022] [Indexed: 06/14/2023]
Abstract
Cotton fiber development is still an intriguing question to understand fiber commitment and development. At different fiber developmental stages, many genes change their expression pattern and have a pivotal role in fiber quality and yield. Recently, numerous studies have been conducted for transcriptional regulation of fiber, and raw data were deposited to the public repository for comprehensive integrative analysis. Here, we remapped > 380 cotton RNAseq data with uniform mapping strategies that span ∼400 fold coverage to the genome. We identified stage-specific features related to fiber cell commitment, initiation, elongation, and Secondary Cell Wall (SCW) synthesis and their putative cis-regulatory elements for the specific regulation in fiber development. We also mined Exclusively Expressed Transcripts (EETs) that were positively selected during cotton fiber evolution and domestication. Furthermore, the expression of EETs was validated in 100 cotton genotypes through the nCounter assay and correlated with different fiber-related traits. Thus, our data mining study reveals several important features related to cotton fiber development and improvement, which were consolidated in the "CottonExpress-omics" database.
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Affiliation(s)
- Priti Prasad
- Division of Molecular Biology and Biotechnology, CSIR-National Botanical Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Uzma Khatoon
- Division of Molecular Biology and Biotechnology, CSIR-National Botanical Research Institute, Lucknow, India
- Department of Botany, University of Lucknow, Lucknow, India
| | - Rishi Kumar Verma
- Division of Molecular Biology and Biotechnology, CSIR-National Botanical Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Shahre Aalam
- Division of Molecular Biology and Biotechnology, CSIR-National Botanical Research Institute, Lucknow, India
| | - Ajay Kumar
- Division of Molecular Biology and Biotechnology, CSIR-National Botanical Research Institute, Lucknow, India
| | | | | | - Sumit K. Bag
- Division of Molecular Biology and Biotechnology, CSIR-National Botanical Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Samir V. Sawant
- Division of Molecular Biology and Biotechnology, CSIR-National Botanical Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
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Blasio F, Prieto P, Pradillo M, Naranjo T. Genomic and Meiotic Changes Accompanying Polyploidization. PLANTS (BASEL, SWITZERLAND) 2022; 11:125. [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] [Grants] [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.)
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Martín AC, Alabdullah AK, Moore G. A separation-of-function ZIP4 wheat mutant allows crossover between related chromosomes and is meiotically stable. Sci Rep 2021; 11:21811. [PMID: 34750469 PMCID: PMC8575954 DOI: 10.1038/s41598-021-01379-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 10/27/2021] [Indexed: 12/12/2022] Open
Abstract
Many species, including most flowering plants, are polyploid, possessing multiple genomes. During polyploidisation, fertility is preserved via the evolution of mechanisms to control the behaviour of these multiple genomes during meiosis. On the polyploidisation of wheat, the major meiotic gene ZIP4 duplicated and diverged, with the resulting new gene TaZIP4-B2 being inserted into chromosome 5B. Previous studies showed that this TaZIP4-B2 promotes pairing and synapsis between wheat homologous chromosomes, whilst suppressing crossover between related (homoeologous) chromosomes. Moreover, in wheat, the presence of TaZIP4-B2 preserves up to 50% of grain number. The present study exploits a 'separation-of-function' wheat Tazip4-B2 mutant named zip4-ph1d, in which the Tazip4-B2 copy still promotes correct pairing and synapsis between homologues (resulting in the same pollen profile and fertility normally found in wild type wheat), but which also allows crossover between the related chromosomes in wheat haploids of this mutant. This suggests an improved utility for the new zip4-ph1d mutant line during wheat breeding, compared to the previously described CRISPR Tazip4-B2 and ph1 mutant lines. The results also reveal that loss of suppression of homoeologous crossover between wheat chromosomes does not in itself reduce wheat fertility when promotion of homologous pairing and synapsis by TaZIP4-B2 is preserved.
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Affiliation(s)
- Azahara C Martín
- Crop Genetics Department, John Innes Centre, Colney, Norwich, NR4 7UH, UK.
| | | | - Graham Moore
- Crop Genetics Department, John Innes Centre, Colney, Norwich, NR4 7UH, UK
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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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Tock AJ, Holland DM, Jiang W, Osman K, Sanchez-Moran E, Higgins JD, Edwards KJ, Uauy C, Franklin FCH, Henderson IR. Crossover-active regions of the wheat genome are distinguished by DMC1, the chromosome axis, H3K27me3, and signatures of adaptation. Genome Res 2021; 31:1614-1628. [PMID: 34426514 PMCID: PMC8415368 DOI: 10.1101/gr.273672.120] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 07/20/2021] [Indexed: 12/18/2022]
Abstract
The hexaploid bread wheat genome comprises over 16 gigabases of sequence across 21 chromosomes. Meiotic crossovers are highly polarized along the chromosomes, with elevation in the gene-dense distal regions and suppression in the Gypsy retrotransposon-dense centromere-proximal regions. We profiled the genomic landscapes of the meiotic recombinase DMC1 and the chromosome axis protein ASY1 in wheat and investigated their relationships with crossovers, chromatin state, and genetic diversity. DMC1 and ASY1 chromatin immunoprecipitation followed by sequencing (ChIP-seq) revealed strong co-enrichment in the distal, crossover-active regions of the wheat chromosomes. Distal ChIP-seq enrichment is consistent with spatiotemporally biased cytological immunolocalization of DMC1 and ASY1 close to the telomeres during meiotic prophase I. DMC1 and ASY1 ChIP-seq peaks show significant overlap with genes and transposable elements in the Mariner and Mutator superfamilies. However, DMC1 and ASY1 ChIP-seq peaks were detected along the length of each chromosome, including in low-crossover regions. At the fine scale, crossover elevation at DMC1 and ASY1 peaks and genes correlates with enrichment of the Polycomb histone modification H3K27me3. This indicates a role for facultative heterochromatin, coincident with high DMC1 and ASY1, in promoting crossovers in wheat and is reflected in distalized H3K27me3 enrichment observed via ChIP-seq and immunocytology. Genes with elevated crossover rates and high DMC1 and ASY1 ChIP-seq signals are overrepresented for defense-response and immunity annotations, have higher sequence polymorphism, and exhibit signatures of selection. Our findings are consistent with meiotic recombination promoting genetic diversity, shaping host–pathogen co-evolution, and accelerating adaptation by increasing the efficiency of selection.
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Affiliation(s)
- Andrew J Tock
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | - Daniel M Holland
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | - Wei Jiang
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | - Kim Osman
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | | | - James D Higgins
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Keith J Edwards
- School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, United Kingdom
| | | | - F Chris H Franklin
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Ian R Henderson
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
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Hassani‐Pak K, Singh A, Brandizi M, Hearnshaw J, Parsons JD, Amberkar S, Phillips AL, Doonan JH, Rawlings C. KnetMiner: a comprehensive approach for supporting evidence-based gene discovery and complex trait analysis across species. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:1670-1678. [PMID: 33750020 PMCID: PMC8384599 DOI: 10.1111/pbi.13583] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 12/17/2020] [Accepted: 03/16/2021] [Indexed: 05/03/2023]
Abstract
The generation of new ideas and scientific hypotheses is often the result of extensive literature and database searches, but, with the growing wealth of public and private knowledge, the process of searching diverse and interconnected data to generate new insights into genes, gene networks, traits and diseases is becoming both more complex and more time-consuming. To guide this technically challenging data integration task and to make gene discovery and hypotheses generation easier for researchers, we have developed a comprehensive software package called KnetMiner which is open-source and containerized for easy use. KnetMiner is an integrated, intelligent, interactive gene and gene network discovery platform that supports scientists explore and understand the biological stories of complex traits and diseases across species. It features fast algorithms for generating rich interactive gene networks and prioritizing candidate genes based on knowledge mining approaches. KnetMiner is used in many plant science institutions and has been adopted by several plant breeding organizations to accelerate gene discovery. The software is generic and customizable and can therefore be readily applied to new species and data types; for example, it has been applied to pest insects and fungal pathogens; and most recently repurposed to support COVID-19 research. Here, we give an overview of the main approaches behind KnetMiner and we report plant-centric case studies for identifying genes, gene networks and trait relationships in Triticum aestivum (bread wheat), as well as, an evidence-based approach to rank candidate genes under a large Arabidopsis thaliana QTL. KnetMiner is available at: https://knetminer.org.
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10
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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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11
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Osman K, Algopishi U, Higgins JD, Henderson IR, Edwards KJ, Franklin FCH, Sanchez-Moran E. Distal Bias of Meiotic Crossovers in Hexaploid Bread Wheat Reflects Spatio-Temporal Asymmetry of the Meiotic Program. FRONTIERS IN PLANT SCIENCE 2021; 12:631323. [PMID: 33679846 DOI: 10.33892/ffpls.2021.631323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/18/2021] [Indexed: 05/25/2023]
Abstract
Meiotic recombination generates genetic variation and provides physical links between homologous chromosomes (crossovers) essential for accurate segregation. In cereals the distribution of crossovers, cytologically evident as chiasmata, is biased toward the distal regions of chromosomes. This creates a bottleneck for plant breeders in the development of varieties with improved agronomic traits, as genes situated in the interstitial and centromere proximal regions of chromosomes rarely recombine. Recent advances in wheat genomics and genome engineering combined with well-developed wheat cytogenetics offer new opportunities to manipulate recombination and unlock genetic variation. As a basis for these investigations we have carried out a detailed analysis of meiotic progression in hexaploid wheat (Triticum aestivum) using immunolocalization of chromosome axis, synaptonemal complex and recombination proteins. 5-Bromo-2'-deoxyuridine (BrdU) labeling was used to determine the chronology of key events in relation to DNA replication. Axis morphogenesis, synapsis and recombination initiation were found to be spatio-temporally coordinated, beginning in the gene-dense distal chromosomal regions and later occurring in the interstitial/proximal regions. Moreover, meiotic progression in the distal regions was coordinated with the conserved chromatin cycles that are a feature of meiosis. This mirroring of the chiasma bias was also evident in the distribution of the gene-associated histone marks, H3K4me3 and H3K27me3; the repeat-associated mark, H3K27me1; and H3K9me3. We believe that this study provides a cytogenetic framework for functional studies and ongoing initiatives to manipulate recombination in the wheat genome.
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Affiliation(s)
- Kim Osman
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Uthman Algopishi
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - James D Higgins
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Ian R Henderson
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Keith J Edwards
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - F Chris H Franklin
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
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12
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Serra H, Svačina R, Baumann U, Whitford R, Sutton T, Bartoš J, Sourdille P. Ph2 encodes the mismatch repair protein MSH7-3D that inhibits wheat homoeologous recombination. Nat Commun 2021; 12:803. [PMID: 33547285 PMCID: PMC7865012 DOI: 10.1038/s41467-021-21127-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 01/13/2021] [Indexed: 02/06/2023] Open
Abstract
Meiotic recombination is a critical process for plant breeding, as it creates novel allele combinations that can be exploited for crop improvement. In wheat, a complex allohexaploid that has a diploid-like behaviour, meiotic recombination between homoeologous or alien chromosomes is suppressed through the action of several loci. Here, we report positional cloning of Pairing homoeologous 2 (Ph2) and functional validation of the wheat DNA mismatch repair protein MSH7-3D as a key inhibitor of homoeologous recombination, thus solving a half-century-old question. Similar to ph2 mutant phenotype, we show that mutating MSH7-3D induces a substantial increase in homoeologous recombination (up to 5.5 fold) in wheat-wild relative hybrids, which is also associated with a reduction in homologous recombination. These data reveal a role for MSH7-3D in meiotic stabilisation of allopolyploidy and provides an opportunity to improve wheat's genetic diversity through alien gene introgression, a major bottleneck facing crop improvement.
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Affiliation(s)
- Heïdi Serra
- Genetics, Diversity and Ecophysiology of Cereals, UMR 1095, INRAE, Université Clermont Auvergne, Clermont-Ferrand, France. .,Genetics, Reproduction and Development, CNRS, Inserm, Université Clermont Auvergne, Clermont-Ferrand, France.
| | - Radim Svačina
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic
| | - Ute Baumann
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, Australia
| | - Ryan Whitford
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, Australia
| | - Tim Sutton
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, Australia.,South Australian Research and Development Institute, Adelaide, SA, Australia
| | - Jan Bartoš
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic
| | - Pierre Sourdille
- Genetics, Diversity and Ecophysiology of Cereals, UMR 1095, INRAE, Université Clermont Auvergne, Clermont-Ferrand, France.
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13
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Osman K, Algopishi U, Higgins JD, Henderson IR, Edwards KJ, Franklin FCH, Sanchez-Moran E. Distal Bias of Meiotic Crossovers in Hexaploid Bread Wheat Reflects Spatio-Temporal Asymmetry of the Meiotic Program. FRONTIERS IN PLANT SCIENCE 2021; 12:631323. [PMID: 33679846 PMCID: PMC7928317 DOI: 10.3389/fpls.2021.631323] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/18/2021] [Indexed: 05/09/2023]
Abstract
Meiotic recombination generates genetic variation and provides physical links between homologous chromosomes (crossovers) essential for accurate segregation. In cereals the distribution of crossovers, cytologically evident as chiasmata, is biased toward the distal regions of chromosomes. This creates a bottleneck for plant breeders in the development of varieties with improved agronomic traits, as genes situated in the interstitial and centromere proximal regions of chromosomes rarely recombine. Recent advances in wheat genomics and genome engineering combined with well-developed wheat cytogenetics offer new opportunities to manipulate recombination and unlock genetic variation. As a basis for these investigations we have carried out a detailed analysis of meiotic progression in hexaploid wheat (Triticum aestivum) using immunolocalization of chromosome axis, synaptonemal complex and recombination proteins. 5-Bromo-2'-deoxyuridine (BrdU) labeling was used to determine the chronology of key events in relation to DNA replication. Axis morphogenesis, synapsis and recombination initiation were found to be spatio-temporally coordinated, beginning in the gene-dense distal chromosomal regions and later occurring in the interstitial/proximal regions. Moreover, meiotic progression in the distal regions was coordinated with the conserved chromatin cycles that are a feature of meiosis. This mirroring of the chiasma bias was also evident in the distribution of the gene-associated histone marks, H3K4me3 and H3K27me3; the repeat-associated mark, H3K27me1; and H3K9me3. We believe that this study provides a cytogenetic framework for functional studies and ongoing initiatives to manipulate recombination in the wheat genome.
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Affiliation(s)
- Kim Osman
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
- *Correspondence: Kim Osman
| | - Uthman Algopishi
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - James D. Higgins
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Ian R. Henderson
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Keith J. Edwards
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | | | - Eugenio Sanchez-Moran
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
- Eugenio Sanchez-Moran
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14
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Benyahya F, Nadaud I, Da Ines O, Rimbert H, White C, Sourdille P. SPO11.2 is essential for programmed double-strand break formation during meiosis in bread wheat (Triticum aestivum L.). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:30-43. [PMID: 32603485 DOI: 10.1111/tpj.14903] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 05/20/2023]
Abstract
Meiotic recombination is initiated by formation of DNA double-strand breaks (DSBs). This involves a protein complex that includes in plants the two similar proteins, SPO11-1 and SPO11-2. We analysed the sequences of SPO11-2 in hexaploid bread wheat (Triticum aestivum), as well as in its diploid and tetraploid progenitors. We investigated its role during meiosis using single, double and triple mutants. The three homoeologous SPO11-2 copies of hexaploid wheat exhibit high nucleotide and amino acid similarities with those of the diploids, tetraploids and Arabidopsis. Interestingly, however, two nucleotides deleted in exon-2 of the A copy lead to a premature stop codon and suggest that it encodes a non-functional protein. Remarkably, the mutation was absent from the diploid A-relative Triticum urartu, but present in the tetraploid Triticum dicoccoides and in different wheat cultivars indicating that the mutation occurred after the first polyploidy event and has since been conserved. We further show that triple mutants with all three copies (A, B, D) inactivated are sterile. Cytological analyses of these mutants show synapsis defects, accompanied by severe reductions in bivalent formation and numbers of DMC1 foci, thus confirming the essential role of TaSPO11-2 in meiotic recombination in wheat. In accordance with its 2-nucleotide deletion in exon-2, double mutants for which only the A copy remained are also sterile. Notwithstanding, some DMC1 foci remain visible in this mutant, suggesting a residual activity of the A copy, albeit not sufficient to restore fertility.
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Affiliation(s)
- Fatiha Benyahya
- Genetics, Diversity & Ecophysiology of Cereals, INRAE, Université Clermont-Auvergne, Clermont-Ferrand, 63000, France
| | - Isabelle Nadaud
- Genetics, Diversity & Ecophysiology of Cereals, INRAE, Université Clermont-Auvergne, Clermont-Ferrand, 63000, France
| | - Olivier Da Ines
- Génétique, Reproduction et Développement, UMR CNRS 6293 - Université Clermont Auvergne - INSERM U1103, Clermont-Ferrand, 63001, France
| | - Hélène Rimbert
- Genetics, Diversity & Ecophysiology of Cereals, INRAE, Université Clermont-Auvergne, Clermont-Ferrand, 63000, France
| | - Charles White
- Génétique, Reproduction et Développement, UMR CNRS 6293 - Université Clermont Auvergne - INSERM U1103, Clermont-Ferrand, 63001, France
| | - Pierre Sourdille
- Genetics, Diversity & Ecophysiology of Cereals, INRAE, Université Clermont-Auvergne, Clermont-Ferrand, 63000, France
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15
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Desjardins SD, Ogle DE, Ayoub MA, Heckmann S, Henderson IR, Edwards KJ, Higgins JD. MutS homologue 4 and MutS homologue 5 Maintain the Obligate Crossover in Wheat Despite Stepwise Gene Loss following Polyploidization. PLANT PHYSIOLOGY 2020; 183:1545-1558. [PMID: 32527734 PMCID: PMC7401138 DOI: 10.1104/pp.20.00534] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/02/2020] [Indexed: 05/23/2023]
Abstract
Crossovers (COs) ensure accurate chromosome segregation during meiosis while creating novel allelic combinations. Here, we show that allotetraploid (AABB) durum wheat (Triticum turgidum ssp. durum) utilizes two pathways of meiotic recombination. The class I pathway requires MSH4 and MSH5 (MutSγ) to maintain the obligate CO/chiasma and accounts for ∼85% of meiotic COs, whereas the residual ∼15% are consistent with the class II CO pathway. Class I and class II chiasmata are skewed toward the chromosome ends, but class II chiasmata are significantly more distal than class I chiasmata. Chiasma distribution does not reflect the abundance of double-strand breaks, detected by proxy as RAD51 foci at leptotene, but only ∼2.3% of these sites mature into chiasmata. MutSγ maintains the obligate chiasma despite a 5.4-kb deletion in MSH5B rendering it nonfunctional, which occurred early in the evolution of tetraploid wheat and was then domesticated into hexaploid (AABBDD) common wheat (Triticum aestivum), as well as an 8-kb deletion in MSH4D in hexaploid wheat, predicted to create a nonfunctional pseudogene. Stepwise loss of MSH5B and MSH4D following hybridization and whole-genome duplication may have occurred due to gene redundancy (as functional copies of MSH5A, MSH4A, and MSH4B are still present in the tetraploid and MSH5A, MSH5D, MSH4A, and MSH4B are present in the hexaploid) or as an adaptation to modulate recombination in allopolyploid wheat.
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Affiliation(s)
- Stuart D Desjardins
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Daisy E Ogle
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Mohammad A Ayoub
- Independent Research Group Meiosis, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, D-06466 Stadt Seeland, Germany
| | - Stefan Heckmann
- Independent Research Group Meiosis, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, D-06466 Stadt Seeland, Germany
| | - Ian R Henderson
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | | | - James D Higgins
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
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16
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Nieto Feliner G, Casacuberta J, Wendel JF. Genomics of Evolutionary Novelty in Hybrids and Polyploids. Front Genet 2020; 11:792. [PMID: 32849797 PMCID: PMC7399645 DOI: 10.3389/fgene.2020.00792] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/03/2020] [Indexed: 12/15/2022] Open
Abstract
It has long been recognized that hybridization and polyploidy are prominent processes in plant evolution. Although classically recognized as significant in speciation and adaptation, recognition of the importance of interspecific gene flow has dramatically increased during the genomics era, concomitant with an unending flood of empirical examples, with or without genome doubling. Interspecific gene flow is thus increasingly thought to lead to evolutionary innovation and diversification, via adaptive introgression, homoploid hybrid speciation and allopolyploid speciation. Less well understood, however, are the suite of genetic and genomic mechanisms set in motion by the merger of differentiated genomes, and the temporal scale over which recombinational complexity mediated by gene flow might be expressed and exposed to natural selection. We focus on these issues here, considering the types of molecular genetic and genomic processes that might be set in motion by the saltational event of genome merger between two diverged species, either with or without genome doubling, and how these various processes can contribute to novel phenotypes. Genetic mechanisms include the infusion of new alleles and the genesis of novel structural variation including translocations and inversions, homoeologous exchanges, transposable element mobilization and novel insertional effects, presence-absence variation and copy number variation. Polyploidy generates massive transcriptomic and regulatory alteration, presumably set in motion by disrupted stoichiometries of regulatory factors, small RNAs and other genome interactions that cascade from single-gene expression change up through entire networks of transformed regulatory modules. We highlight both these novel combinatorial possibilities and the range of temporal scales over which such complexity might be generated, and thus exposed to natural selection and drift.
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Affiliation(s)
- Gonzalo Nieto Feliner
- Department of Biodiversity and Conservation, Real Jardín Botánico, CSIC, Madrid, Spain
| | - Josep Casacuberta
- Center for Research in Agricultural Genomics, CRAG (CSIC-IRTA-UAB-UB), Barcelona, Spain
| | - Jonathan F. Wendel
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, United States
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17
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Ali MW, Borrill P. Applying genomic resources to accelerate wheat biofortification. Heredity (Edinb) 2020; 125:386-395. [PMID: 32528079 DOI: 10.1038/s41437-020-0326-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 02/06/2023] Open
Abstract
Wheat has low levels of the micronutrients iron and zinc in the grain, which contributes to 2 billion people suffering from micronutrient deficiency globally. While wheat flour is commonly fortified during processing, an attractive and more sustainable solution is biofortification, which could improve micronutrient content in the human diet, without the sustainability issues and costs associated with conventional fortification. Although many studies have used quantitative trait loci mapping and genome-wide association to identify genetic loci to improve micronutrient contents, recent developments in genomics offer an opportunity to accelerate marker discovery and use gene-focussed approaches to engineer improved micronutrient content in wheat. The recent publication of a high-quality wheat genome sequence, alongside gene expression atlases, variation datasets and sequenced mutant populations, provides a foundation to identify genetic loci and genes controlling micronutrient content in wheat. We discuss how novel genomic resources can identify candidate genes for biofortification, integrating knowledge from other cereal crops, and how these genes can be tested using gene editing, transgenic and TILLING approaches. Finally, we highlight key challenges remaining to develop wheat cultivars with high levels of iron and zinc.
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Affiliation(s)
- Muhammad Waqas Ali
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Philippa Borrill
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
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18
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Draeger T, C Martin A, Alabdullah AK, Pendle A, Rey MD, Shaw P, Moore G. Dmc1 is a candidate for temperature tolerance during wheat meiosis. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:809-828. [PMID: 31853574 PMCID: PMC7021665 DOI: 10.1007/s00122-019-03508-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 12/10/2019] [Indexed: 05/21/2023]
Abstract
KEY MESSAGE The meiotic recombination gene Dmc1 on wheat chromosome 5D has been identified as a candidate for the maintenance of normal chromosome synapsis and crossover at low and possibly high temperatures. We initially assessed the effects of low temperature on meiotic chromosome synapsis and crossover formation in the hexaploid wheat (Triticum aestivum L.) variety 'Chinese Spring'. At low temperatures, asynapsis and chromosome univalence have been observed before in Chinese Spring lines lacking the long arm of chromosome 5D (5DL), which led to the proposal that 5DL carries a gene (Ltp1) that stabilises wheat chromosome pairing at low temperatures. In the current study, Chinese Spring wild type and 5DL interstitial deletion mutant plants were exposed to low temperature in a controlled environment room during a period from premeiotic interphase to early meiosis I. A 5DL deletion mutant was identified whose meiotic chromosomes exhibit extremely high levels of asynapsis and chromosome univalence at metaphase I after 7 days at 13 °C, suggesting that Ltp1 is deleted in this mutant. Immunolocalisation of the meiotic proteins ASY1 and ZYP1 on ltp1 mutants showed that low temperature results in a failure to complete synapsis at pachytene. KASP genotyping revealed that the ltp1 mutant has a 4-Mb deletion in 5DL. Of 41 genes within this deletion region, the strongest candidate for the stabilisation of chromosome pairing at low temperatures is the meiotic recombination gene Dmc1. The ltp1 mutants were subsequently treated at 30 °C for 24 h during meiosis and exhibited a reduced number of crossovers and increased univalence, though to a lesser extent than at 13 °C. We therefore renamed our ltp1 mutant 'ttmei1' (temperature-tolerant meiosis 1) to reflect this additional loss of high temperature tolerance.
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Affiliation(s)
- Tracie Draeger
- John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK.
| | | | | | - Ali Pendle
- John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - María-Dolores Rey
- Agroforestry and Plant Biochemistry, Proteomics and Systems Biology, Department of Biochemistry and Molecular Biology, University of Cordoba, Cordoba, Spain
| | - Peter Shaw
- John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - Graham Moore
- John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
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19
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Garrido J, Aguilar M, Prieto P. Identification and validation of reference genes for RT-qPCR normalization in wheat meiosis. Sci Rep 2020; 10:2726. [PMID: 32066846 PMCID: PMC7026057 DOI: 10.1038/s41598-020-59580-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 01/30/2020] [Indexed: 12/23/2022] Open
Abstract
Meiosis is a specialized type of cell division occurring in sexually reproducing organisms to generate haploid cells known as gametes. In flowering plants, male gametes are produced in anthers, being encased in pollen grains. Understanding the genetic regulation of meiosis key events such as chromosome recognition and pairing, synapsis and recombination, is needed to manipulate chromosome associations for breeding purposes, particularly in important cereal crops like wheat. Reverse transcription-quantitative PCR (RT-qPCR) is widely used to analyse gene expression and to validate the results obtained by other transcriptomic analyses, like RNA-seq. Selection and validation of appropriate reference genes for RT-qPCR normalization is essential to obtain reproducible and accurate expression data. In this work, twelve candidate reference genes were evaluated using the mainstream algorithms geNorm, Normfinder, BestKeeper and ΔCt, then ranked from most to least suitable for normalization with RefFinder. Different sets of reference genes were recommended to normalize gene expression data in anther meiosis of bread and durum wheat, their corresponding genotypes in the absence of the Ph1 locus and for comparative studies among wheat genotypes. Comparisons between meiotic (anthers) and somatic (leaves and roots) wheat tissues were also carried out. To the best of our knowledge, our study provides the first comprehensive list of reference genes for robust RT-qPCR normalization to study differentially expressed genes during male meiosis in wheat in a breeding framework.
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Affiliation(s)
- José Garrido
- Plant Breeding Department, Institute for Sustainable Agriculture, Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC), Alameda del Obispo s/n, Apartado 4084, 14080, Córdoba, Spain
| | - Miguel Aguilar
- Área de Fisiología Vegetal. Universidad de Córdoba. Campus de Rabanales, edif. C4, 3ª planta, Córdoba, Spain
| | - Pilar Prieto
- Plant Breeding Department, Institute for Sustainable Agriculture, Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC), Alameda del Obispo s/n, Apartado 4084, 14080, Córdoba, Spain.
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