1
|
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.
Collapse
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.)
| |
Collapse
|
2
|
Production of Doubled Haploid Embryos from Cork Oak Anther Cultures by Antimitotic Agents and Temperature Stress. Methods Mol Biol 2021. [PMID: 34270072 DOI: 10.1007/978-1-0716-1331-3_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Cork oak (Quercus suber L.) is a forest tree species of the family Fagaceae. It is characterized by long life cycles which hamper doubled haploid plant production to obtain homozygotes and pure lines. The time-consuming method of repeated backcrossings by conventional breeding techniques to produce pure lines is impractical in woody species. Nevertheless, biotechnology has offered new tools to make it possible. A doubled haploid plant or embryo is one that is developed by the doubling of a haploid set of chromosomes. A protocol to produce doubled haploids of cork oak has been developed through microspore embryogenesis. By a heat stress treatment, the microspores inside the anther leave the gametophytic pathway and react shifting their development to the sporophytic pathway by means of which haploid embryos are obtained. Chromosome duplication of haploids from cork oak anther cultures occurs either spontaneously or may be induced by the application of antimitotic agents (e.g., colchicine, oryzalin, amiprophos-methyl). Furthermore, a genetic test is designed through microsatellite markers to elucidate whether the diploid embryos obtained are originally haploids which spontaneously duplicated their genome, or alternatively those embryos are generated from the diploid tissue of the anther wall. Here we describe a detailed protocol to produce doubled haploid individuals from cork oak anther cultures by using temperature stress and antimitotic agents.
Collapse
|
3
|
Chaikam V, Molenaar W, Melchinger AE, Boddupalli PM. Doubled haploid technology for line development in maize: technical advances and prospects. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2019; 132:3227-3243. [PMID: 31555890 PMCID: PMC6820599 DOI: 10.1007/s00122-019-03433-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/17/2019] [Indexed: 05/05/2023]
Abstract
KEY MESSAGE Increased efficiencies achieved in different steps of DH line production offer greater benefits to maize breeding programs. Doubled haploid (DH) technology has become an integral part of many commercial maize breeding programs as DH lines offer several economic, logistic and genetic benefits over conventional inbred lines. Further, new advances in DH technology continue to improve the efficiency of DH line development and fuel its increased adoption in breeding programs worldwide. The established method for maize DH production covered in this review involves in vivo induction of maternal haploids by a male haploid inducer genotype, identification of haploids from diploids at the seed or seedling stage, chromosome doubling of haploid (D0) seedlings and finally, selfing of fertile D0 plants. Development of haploid inducers with high haploid induction rates and adaptation to different target environments have facilitated increased adoption of DH technology in the tropics. New marker systems for haploid identification, such as the red root marker and high oil marker, are being increasingly integrated into new haploid inducers and have the potential to make DH technology accessible in germplasm such as some Flint, landrace, or tropical material, where the standard R1-nj marker is inhibited. Automation holds great promise to further reduce the cost and time in haploid identification. Increasing success rates in chromosome doubling protocols and/or reducing environmental and human toxicity of chromosome doubling protocols, including research on genetic improvement in spontaneous chromosome doubling, have the potential to greatly reduce the production costs per DH line.
Collapse
Affiliation(s)
- Vijay Chaikam
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF campus, UN Avenue, Gigiri, P.O. Box 1041, Nairobi, 00621, Kenya
| | - Willem Molenaar
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70593, Stuttgart, Germany
| | - Albrecht E Melchinger
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70593, Stuttgart, Germany
| | - Prasanna M Boddupalli
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF campus, UN Avenue, Gigiri, P.O. Box 1041, Nairobi, 00621, Kenya.
| |
Collapse
|
4
|
Chaikam V, Gowda M, Nair SK, Melchinger AE, Boddupalli PM. Genome-wide association study to identify genomic regions influencing spontaneous fertility in maize haploids. EUPHYTICA: NETHERLANDS JOURNAL OF PLANT BREEDING 2019; 215:138. [PMID: 31402796 PMCID: PMC6647887 DOI: 10.1007/s10681-019-2459-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 06/29/2019] [Indexed: 05/18/2023]
Abstract
Efficient production and use of doubled haploid lines can greatly accelerate genetic gains in maize breeding programs. One of the critical steps in standard doubled haploid line production is doubling the haploid genome using toxic and costly mitosis-inhibiting chemicals to achieve fertility in haploids. Alternatively, fertility may be spontaneously restored by natural chromosomal doubling, although generally at a rate too low for practical applications in most germplasm. This is the first large-scale genome-wise association study to analyze spontaneous chromosome doubling in haploids derived from tropical maize inbred lines. Induction crosses between tropicalized haploid inducers and 400 inbred lines were made, and the resulting haploid plants were assessed for haploid male fertility which refers to pollen production and haploid fertility which refers to seed production upon self-fertilization. A small number of genotypes were highly fertile and these fertility traits were highly heritable. Agronomic traits like plant height, ear height and tassel branch number were positively correlated with fertility traits. In contrast, haploid induction rate of the source germplasm and plant aspect were not correlated to fertility traits. Several genomic regions and candidate genes were identified that may control spontaneous fertility restoration. Overall, the study revealed the presence of large variation for both haploid male fertility and haploid fertility which can be potentially exploited for improving the efficiency of doubled haploid derivation in tropical maize germplasm.
Collapse
Affiliation(s)
- Vijay Chaikam
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O. Box 1041–00621, Nairobi, Kenya
| | - Manje Gowda
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O. Box 1041–00621, Nairobi, Kenya
| | - Sudha K. Nair
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Greater Hyderabad, 502324 India
| | - Albrecht E. Melchinger
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70593 Stuttgart, Germany
| | - Prasanna M. Boddupalli
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O. Box 1041–00621, Nairobi, Kenya
| |
Collapse
|
5
|
Organelles maintain spindle position in plant meiosis. Nat Commun 2015; 6:6492. [DOI: 10.1038/ncomms7492] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 02/03/2015] [Indexed: 11/08/2022] Open
|
6
|
De Storme N, Geelen D. Sexual polyploidization in plants--cytological mechanisms and molecular regulation. THE NEW PHYTOLOGIST 2013; 198:670-684. [PMID: 23421646 PMCID: PMC3744767 DOI: 10.1111/nph.12184] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Accepted: 01/01/2013] [Indexed: 05/18/2023]
Abstract
In the plant kingdom, events of whole genome duplication or polyploidization are generally believed to occur via alterations of the sexual reproduction process. Thereby, diploid pollen and eggs are formed that contain the somatic number of chromosomes rather than the gametophytic number. By participating in fertilization, these so-called 2n gametes generate polyploid offspring and therefore constitute the basis for the establishment of polyploidy in plants. In addition, diplogamete formation, through meiotic restitution, is an essential component of apomixis and also serves as an important mechanism for the restoration of F1 hybrid fertility. Characterization of the cytological mechanisms and molecular factors underlying 2n gamete formation is therefore not only relevant for basic plant biology and evolution, but may also provide valuable cues for agricultural and biotechnological applications (e.g. reverse breeding, clonal seeds). Recent data have provided novel insights into the process of 2n pollen and egg formation and have revealed multiple means to the same end. Here, we summarize the cytological mechanisms and molecular regulatory networks underlying 2n gamete formation, and outline important mitotic and meiotic processes involved in the ectopic induction of sexual polyploidization.
Collapse
Affiliation(s)
- Nico De Storme
- Department of Plant Production, Faculty of Bioscience Engineering, University of Ghent, Coupure Links 653, B-9000, Gent, Belgium
| | - Danny Geelen
- Department of Plant Production, Faculty of Bioscience Engineering, University of Ghent, Coupure Links 653, B-9000, Gent, Belgium
| |
Collapse
|