1
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Tan JW, Shinde H, Tesfamicael K, Hu Y, Fruzangohar M, Tricker P, Baumann U, Edwards EJ, Rodríguez López CM. Global transcriptome and gene co-expression network analyses reveal regulatory and non-additive effects of drought and heat stress in grapevine. Front Plant Sci 2023; 14:1096225. [PMID: 36818880 PMCID: PMC9932518 DOI: 10.3389/fpls.2023.1096225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
Despite frequent co-occurrence of drought and heat stress, the molecular mechanisms governing plant responses to these stresses in combination have not often been studied. This is particularly evident in non-model, perennial plants. We conducted large scale physiological and transcriptome analyses to identify genes and pathways associated with grapevine response to drought and/or heat stress during stress progression and recovery. We identified gene clusters with expression correlated to leaf temperature and water stress and five hub genes for the combined stress co-expression network. Several differentially expressed genes were common to the individual and combined stresses, but the majority were unique to the individual or combined stress treatments. These included heat-shock proteins, mitogen-activated kinases, sugar metabolizing enzymes, and transcription factors, while phenylpropanoid biosynthesis and histone modifying genes were unique to the combined stress treatment. Following physiological recovery, differentially expressed genes were found only in plants under heat stress, both alone and combined with drought. Taken collectively, our results suggest that the effect of the combined stress on physiology and gene expression is more severe than that of individual stresses, but not simply additive, and that epigenetic chromatin modifications may play an important role in grapevine responses to combined drought and heat stress.
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Affiliation(s)
- Jia W. Tan
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
| | - Harshraj Shinde
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
| | - Kiflu Tesfamicael
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
- School of Biological Science, The University of Adelaide, Adelaide, SA, Australia
| | - Yikang Hu
- School of Biological Science, The University of Adelaide, Adelaide, SA, Australia
| | - Mario Fruzangohar
- The Biometry Hub, School of Agriculture, Food and Wine & Waite Research Institute, University of Adelaide, Glen Osmond, SA, Australia
| | - Penny Tricker
- School of Agriculture, Food and Wine, The University of Adelaide, Hartley Grove, SA, Australia
- The New Zealand Institute for Plant and Food Research Limited, Plant & Food Research Canterbury Agriculture & Science Centre, Lincoln, New Zealand
| | - Ute Baumann
- School of Agriculture, Food and Wine, The University of Adelaide, Hartley Grove, SA, Australia
| | - Everard J. Edwards
- The Commonwealth Scientific and Industrial Research Organisation (CSIRO) Agriculture & Food, Glen Osmond, SA, Australia
| | - Carlos M. Rodríguez López
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
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Berbel-Filho WM, Pacheco G, Tatarenkov A, Lira MG, Garcia de Leaniz C, Rodríguez López CM, Lima SMQ, Consuegra S. Phylogenomics reveals extensive introgression and a case of mito-nuclear discordance in the killifish genus Kryptolebias. Mol Phylogenet Evol 2022; 177:107617. [PMID: 36038055 DOI: 10.1016/j.ympev.2022.107617] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 08/03/2022] [Accepted: 08/17/2022] [Indexed: 10/15/2022]
Abstract
Introgression is a widespread evolutionary process leading to phylogenetic inconsistencies among distinct parts of the genomes, particularly between mitochondrial and nuclear-based phylogenetic reconstructions (e.g., mito-nuclear discordances). Here, we used mtDNA and genome-wide nuclear sites to provide the first phylogenomic-based hypothesis on the evolutionary relationships within the killifish genus Kryptolebias. In addition, we tested for evidence of past introgression in the genus given the multiple reports of undergoing hybridization between its members. Our mtDNA phylogeny generally agreed with the relationships previously proposed for the genus. However, our reconstruction based on nuclear DNA revealed an unknown lineage - Kryptolebias sp. 'ESP' - as the sister group of the self-fertilizing mangrove killifishes, K. marmoratus and K. hermaphroditus. All individuals sequenced of Kryptolebias sp. 'ESP' had the same mtDNA haplotype commonly observed in K. hermaphroditus, demonstrating a clear case of mito-nuclear discordance. Our analysis further confirmed extensive history of introgression between Kryptolebias sp. 'ESP' and K. hermaphroditus. Population genomics analyses indicate no current gene flow between the two lineages, despite their current sympatry and history of introgression. We also confirmed introgression between other species pairs in the genus that have been recently reported to form hybrid zones. Overall, our study provides a phylogenomic reconstruction covering most of the Kryptolebias species, reveals a new lineage hidden in a case of mito-nuclear discordance, and provides evidence of multiple events of ancestral introgression in the genus. These findings underscore the importance of investigating different genomic information in a phylogenetic framework, particularly in taxa where introgression is common as in the sexually diverse mangrove killifishes.
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Affiliation(s)
- Waldir M Berbel-Filho
- Department of Biology, University of Oklahoma, Norman, OK, USA(1); Department of Biosciences, College of Science, Swansea University, Swansea, UK.
| | - George Pacheco
- Section for Marine Living Resources, National Institute of Aquatic Resources, Technical University of Denmark, Vejlsøvej 39, 8600 Silkeborg, Denmark
| | - Andrey Tatarenkov
- Department of Ecology and Evolutionary Biology, University of California, Irvine, USA
| | - Mateus G Lira
- Laboratório de Ictiologia Sistemática e Evolutiva, Departamento de Botânica e Zoologia, Universidade Federal do Rio Grande, Natal, Brazil
| | | | - Carlos M Rodríguez López
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Sergio M Q Lima
- Laboratório de Ictiologia Sistemática e Evolutiva, Departamento de Botânica e Zoologia, Universidade Federal do Rio Grande, Natal, Brazil
| | - Sofia Consuegra
- Department of Biosciences, College of Science, Swansea University, Swansea, UK
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Fabres PJ, Anand L, Sai N, Pederson S, Zheng F, Stewart AA, Clements B, Lampugnani ER, Breen J, Gilliham M, Tricker P, Rodríguez López CM, David R. Tissue and regional expression patterns of dicistronic tRNA-mRNA transcripts in grapevine (Vitis vinifera) and their evolutionary co-appearance with vasculature in land plants. Hortic Res 2021; 8:137. [PMID: 34059643 PMCID: PMC8166872 DOI: 10.1038/s41438-021-00572-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 04/13/2021] [Accepted: 04/19/2021] [Indexed: 06/02/2023]
Abstract
Transfer RNAs (tRNA) are crucial adaptor molecules between messenger RNA (mRNA) and amino acids. Recent evidence in plants suggests that dicistronic tRNA-like structures also act as mobile signals for mRNA transcripts to move between distant tissues. Co-transcription is not a common feature in the plant nuclear genome and, in the few cases where polycistronic transcripts have been found, they include non-coding RNA species, such as small nucleolar RNAs and microRNAs. It is not known, however, the extent to which dicistronic transcripts of tRNA and mRNAs are expressed in field-grown plants, or the factors contributing to their expression. We analysed tRNA-mRNA dicistronic transcripts in the major horticultural crop grapevine (Vitis vinifera) using a novel pipeline developed to identify dicistronic transcripts from high-throughput RNA-sequencing data. We identified dicistronic tRNA-mRNA in leaf and berry samples from 22 commercial vineyards. Of the 124 tRNA genes that were expressed in both tissues, 18 tRNA were expressed forming part of 19 dicistronic tRNA-mRNAs. The presence and abundance of dicistronic molecules was tissue and geographic sub-region specific. In leaves, the expression patterns of dicistronic tRNA-mRNAs significantly correlated with tRNA expression, suggesting that their transcriptional regulation might be linked. We also found evidence of syntenic genomic arrangements of tRNAs and protein-coding genes between grapevine and Arabidopsis thaliana, and widespread prevalence of dicistronic tRNA-mRNA transcripts among vascular land plants but no evidence of these transcripts in non-vascular lineages. This suggests that the appearance of plant vasculature and tRNA-mRNA occurred concurrently during the evolution of land plants.
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Affiliation(s)
- Pastor Jullian Fabres
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Lakshay Anand
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Na Sai
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
- ARC Centre of Excellence in Plant Energy Biology, Waite Research Institute & School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
| | - Stephen Pederson
- Bioinformatics Hub, School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Fei Zheng
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
- ARC Centre of Excellence in Plant Energy Biology, Waite Research Institute & School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
| | - Alexander A Stewart
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Benjamin Clements
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Edwin R Lampugnani
- School of Biosciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - James Breen
- Bioinformatics Hub, School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Matthew Gilliham
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
- ARC Centre of Excellence in Plant Energy Biology, Waite Research Institute & School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
- ARC Industrial Transformation Training Centre in Innovative Wine Production, Waite Research Institute & School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
| | - Penny Tricker
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
| | - Carlos M Rodríguez López
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA.
| | - Rakesh David
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
- ARC Centre of Excellence in Plant Energy Biology, Waite Research Institute & School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA, Australia
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Zhou J, Cavagnaro TR, De Bei R, Nelson TM, Stephen JR, Metcalfe A, Gilliham M, Breen J, Collins C, López CMR. Wine Terroir and the Soil Bacteria: An Amplicon Sequencing-Based Assessment of the Barossa Valley and Its Sub-Regions. Front Microbiol 2021; 11:597944. [PMID: 33488543 PMCID: PMC7817890 DOI: 10.3389/fmicb.2020.597944] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 12/04/2020] [Indexed: 02/01/2023] Open
Abstract
A wines' terroir, represented as wine traits with regional distinctiveness, is a reflection of both the biophysical and human-driven conditions in which the grapes were grown and wine made. Soil is an important factor contributing to the uniqueness of a wine produced by vines grown in specific conditions. Here, we evaluated the impact of environmental variables on the soil bacteria of 22 Barossa Valley vineyard sites based on the 16S rRNA gene hypervariable region 4. In this study, we report that both dispersal isolation by geographic distance and environmental heterogeneity (soil plant-available P content, elevation, rainfall, temperature, spacing between row and spacing between vine) contribute to microbial community dissimilarity between vineyards. Vineyards located in cooler and wetter regions showed lower beta diversity and a higher ratio of dominant taxa. Differences in soil bacterial community composition were significantly associated with differences in fruit and wine composition. Our results suggest that environmental factors affecting wine terroir, may be mediated by changes in microbial structure, thus providing a basic understanding of how growing conditions affect interactions between plants and their soil bacteria.
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Affiliation(s)
- Jia Zhou
- School of Agriculture Food & Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - Timothy R. Cavagnaro
- School of Agriculture Food & Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - Roberta De Bei
- School of Agriculture Food & Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - Tiffanie M. Nelson
- Queensland Facility for Advanced Bioinformatics, School of Medicine, Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia
| | - John R. Stephen
- School of Agriculture Food & Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - Andrew Metcalfe
- School of Mathematical Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Matthew Gilliham
- School of Agriculture Food & Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA, Australia
- ARC Industrial Transformation Training Centre for Innovative Wine Production, Waite Research Institute, Adelaide, SA, Australia
| | - James Breen
- Bioinformatics Hub, School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
- Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Cassandra Collins
- School of Agriculture Food & Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA, Australia
- ARC Industrial Transformation Training Centre for Innovative Wine Production, Waite Research Institute, Adelaide, SA, Australia
| | - Carlos M. Rodríguez López
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
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5
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Corbin KR, Bolt B, Rodríguez López CM. Breeding for Beneficial Microbial Communities Using Epigenomics. Front Microbiol 2020; 11:937. [PMID: 32477316 PMCID: PMC7242621 DOI: 10.3389/fmicb.2020.00937] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 04/20/2020] [Indexed: 02/03/2023] Open
Affiliation(s)
- Kendall R Corbin
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States.,Biosystems and Agricultural Engineering, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
| | - Bridget Bolt
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
| | - Carlos M Rodríguez López
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States
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6
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Akomeah B, Quain MD, Ramesh SA, Anand L, Rodríguez López CM. Common garden experiment reveals altered nutritional values and DNA methylation profiles in micropropagated three elite Ghanaian sweet potato genotypes. PLoS One 2019; 14:e0208214. [PMID: 31026262 PMCID: PMC6485893 DOI: 10.1371/journal.pone.0208214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 04/07/2019] [Indexed: 11/18/2022] Open
Abstract
Micronutrient deficiency is the cause of multiple diseases in developing countries. Staple crop biofortification is an efficient means to combat such deficiencies in the diets of local consumers. Biofortified lines of sweet potato (Ipomoea batata L. Lam) with enhanced beta-carotene content have been developed in Ghana to alleviate Vitamin A Deficiency. These genotypes are propagated using meristem micropropagation to ensure the generation of virus-free propagules. In vitro culture exposes micropropagated plants to conditions that can lead to the accumulation of somaclonal variation with the potential to generate unwanted aberrant phenotypes. However, the effect of micropropagation induced somaclonal variation on the production of key nutrients by field-grown plants has not been previously studied. Here we assessed the extent of in vitro culture induced somaclonal variation, at a phenotypic, compositional and genetic/epigenetic level, by comparing field-maintained and micropropagated lines of three elite Ghanaian sweet potato genotypes grown in a common garden. Although micropropagated plants presented no observable morphological abnormalities compared to field maintained lines, they presented significantly lower levels of iron, total protein, zinc, and glucose. Methylation Sensitive Amplification Polymorphism analysis showed a high level of in vitro culture induced molecular variation in micropropagated plants. Epigenetic, rather than genetic variation, accounts for most of the observed molecular variability. Taken collectively, our results highlight the importance of ensuring the clonal fidelity of the micropropagated biofortified lines in order to reduce potential losses in the nutritional value prior to their commercial release.
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Affiliation(s)
- Belinda Akomeah
- ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, PMB1 Glen Osmond, South Africa, Australia
- The Waite Research Institute and The School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1 Glen Osmond, South Africa, Australia
- CSIR-Crops Research Institute, Kumasi, Ghana
| | | | - Sunita A Ramesh
- ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, PMB1 Glen Osmond, South Africa, Australia
- The Waite Research Institute and The School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1 Glen Osmond, South Africa, Australia
| | - Lakshay Anand
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, Kentucky, United States America
| | - Carlos M. Rodríguez López
- The Waite Research Institute and The School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1 Glen Osmond, South Africa, Australia
- Environmental Epigenetics and Genetics Group, Department of Horticulture, College of Agriculture, Food and Environment, University of Kentucky, Lexington, Kentucky, United States America
- * E-mail:
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Fabres PJ, Collins C, Cavagnaro TR, Rodríguez López CM. A Concise Review on Multi-Omics Data Integration for Terroir Analysis in Vitis vinifera. Front Plant Sci 2017; 8:1065. [PMID: 28676813 PMCID: PMC5477006 DOI: 10.3389/fpls.2017.01065] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 06/02/2017] [Indexed: 05/19/2023]
Abstract
Vitis vinifera (grapevine) is one of the most important fruit crops, both for fresh consumption and wine and spirit production. The term terroir is frequently used in viticulture and the wine industry to relate wine sensory attributes to its geographic origin. Although, it can be cultivated in a wide range of environments, differences in growing conditions have a significant impact on fruit traits that ultimately affect wine quality. Understanding how fruit quality and yield are controlled at a molecular level in grapevine in response to environmental cues has been a major driver of research. Advances in the area of genomics, epigenomics, transcriptomics, proteomics and metabolomics, have significantly increased our knowledge on the abiotic regulation of yield and quality in many crop species, including V. vinifera. The integrated analysis of multiple 'omics' can give us the opportunity to better understand how plants modulate their response to different environments. However, 'omics' technologies provide a large amount of biological data and its interpretation is not always straightforward, especially when different 'omic' results are combined. Here we examine the current strategies used to integrate multi-omics, and how these have been used in V. vinifera. In addition, we also discuss the importance of including epigenomics data when integrating omics data as epigenetic mechanisms could play a major role as an intermediary between the environment and the genome.
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Affiliation(s)
- Pastor Jullian Fabres
- Environmental Epigenetics and Genetics Group, Plant Research Centre, School of Agriculture, Food and Wine, University of Adelaide, Glen OsmondSA, Australia
| | - Cassandra Collins
- The Waite Research Institute, The School of Agriculture, Food and Wine, The University of Adelaide, Glen OsmondSA, Australia
| | - Timothy R. Cavagnaro
- The Waite Research Institute, The School of Agriculture, Food and Wine, The University of Adelaide, Glen OsmondSA, Australia
| | - Carlos M. Rodríguez López
- Environmental Epigenetics and Genetics Group, Plant Research Centre, School of Agriculture, Food and Wine, University of Adelaide, Glen OsmondSA, Australia
- *Correspondence: Carlos M. Rodríguez López,
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Abstract
We hypothesize that under the predicted scenario of climate change epigenetically mediated environmental sex determination could become an epigenetic trap. Epigenetically regulated environmental sex determination is a mechanism by which species can modulate their breeding strategies to accommodate environmental change. Growing evidence suggests that epigenetic mechanisms may play a key role in phenotypic plasticity and in the rapid adaptation of species to environmental change, through the capacity of organisms to maintain a non-genetic plastic memory of the environmental and ecological conditions experienced by their parents. However, inherited epigenetic variation could also be maladaptive, becoming an epigenetic trap. This is because environmental sex determination can alter sex ratios by increasing the survival of one of the sexes at the expense of negative fitness consequences for the other, which could lead not only to the collapse of natural populations, but also have an impact in farmed animal and plant species.
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Affiliation(s)
- Sofia Consuegra
- Department of Biosciences, College of Science, Swansea University, Swansea, UK.
| | - Carlos M Rodríguez López
- Environmental Epigenetics and Genetics Group, School of Agriculture, University of Adelaide, Glen Osmond, South Australia, Australia.
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Kitimu SR, Taylor J, March TJ, Tairo F, Wilkinson MJ, Rodríguez López CM. Meristem micropropagation of cassava (Manihot esculenta) evokes genome-wide changes in DNA methylation. Front Plant Sci 2015; 6:590. [PMID: 26322052 PMCID: PMC4534864 DOI: 10.3389/fpls.2015.00590] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 07/16/2015] [Indexed: 05/25/2023]
Abstract
There is great interest in the phenotypic, genetic and epigenetic changes associated with plant in vitro culture known as somaclonal variation. In vitro propagation systems that are based on the use of microcuttings or meristem cultures are considered analogous to clonal cuttings and so widely viewed to be largely free from such somaclonal effects. In this study, we surveyed for epigenetic changes during propagation by meristem culture and by field cuttings in five cassava (Manihot esculenta) cultivars. Principal Co-ordinate Analysis of profiles generated by methylation-sensitive amplified polymorphism revealed clear divergence between samples taken from field-grown cuttings and those recovered from meristem culture. There was also good separation between the tissues of field samples but this effect was less distinct among the meristem culture materials. Application of methylation-sensitive Genotype by sequencing identified 105 candidate epimarks that distinguish between field cutting and meristem culture samples. Cross referencing the sequences of these epimarks to the draft cassava genome revealed 102 sites associated with genes whose homologs have been implicated in a range of fundamental biological processes including cell differentiation, development, sugar metabolism, DNA methylation, stress response, photosynthesis, and transposon activation. We explore the relevance of these findings for the selection of micropropagation systems for use on this and other crops.
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Affiliation(s)
- Shedrack R. Kitimu
- Plant Research Centre, School of Agriculture Food and Wine, Faculty of Sciences, University of AdelaideAdelaide, SA, Australia
| | - Julian Taylor
- Biometry Hub, School of Agriculture Food and Wine, Faculty of Sciences, University of AdelaideAdelaide, SA, Australia
| | - Timothy J. March
- School of Agriculture Food and Wine, Faculty of Sciences, University of AdelaideAdelaide, SA, Australia
| | - Fred Tairo
- Mikocheni Agricultural Research InstituteDar es Salaam, Tanzania
| | - Mike J. Wilkinson
- Plant Research Centre, School of Agriculture Food and Wine, Faculty of Sciences, University of AdelaideAdelaide, SA, Australia
| | - Carlos M. Rodríguez López
- Plant Research Centre, School of Agriculture Food and Wine, Faculty of Sciences, University of AdelaideAdelaide, SA, Australia
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Rodríguez López CM, Wilkinson MJ. Epi-fingerprinting and epi-interventions for improved crop production and food quality. Front Plant Sci 2015; 6:397. [PMID: 26097484 PMCID: PMC4456566 DOI: 10.3389/fpls.2015.00397] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Accepted: 05/18/2015] [Indexed: 05/05/2023]
Abstract
Increasing crop production at a time of rapid climate change represents the greatest challenge facing contemporary agricultural research. Our understanding of the genetic control of yield derives from controlled field experiments designed to minimize environmental variance. In spite of these efforts there is substantial residual variability among plants attributable to Genotype × Environment interactions. Recent advances in the field of epigenetics have revealed a plethora of gene control mechanisms that could account for much of this unassigned variation. These systems act as a regulatory interface between the perception of the environment and associated alterations in gene expression. Direct intervention of epigenetic control systems hold the enticing promise of creating new sources of variability that could enhance crop performance. Equally, understanding the relationship between various epigenetic states and responses of the crop to specific aspects of the growing environment (epigenetic fingerprinting) could allow for a more tailored approach to plant agronomy. In this review, we explore the many ways in which epigenetic interventions and epigenetic fingerprinting can be deployed for the improvement of crop production and quality.
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Affiliation(s)
- Carlos M. Rodríguez López
- *Correspondence: Carlos M. Rodríguez López, Plant Research Centre, School of Agriculture, Food and Wine, Faculty of Sciences, University of Adelaide, Waite Campus, PMB1, Glen Osmond, Adelaide, SA 5064, Australia
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11
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Róis AS, Rodríguez López CM, Cortinhas A, Erben M, Espírito-Santo D, Wilkinson MJ, Caperta AD. Epigenetic rather than genetic factors may explain phenotypic divergence between coastal populations of diploid and tetraploid Limonium spp. (Plumbaginaceae) in Portugal. BMC Plant Biol 2013; 13:205. [PMID: 24314092 PMCID: PMC3884021 DOI: 10.1186/1471-2229-13-205] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 11/26/2013] [Indexed: 05/09/2023]
Abstract
BACKGROUND The genus Limonium Miller comprises annual and perennial halophytes that can produce sexual and/or asexual seeds (apomixis). Genetic and epigenetic (DNA methylation) variation patterns were investigated in populations of three phenotypically similar putative sexual diploid species (L. nydeggeri, L. ovalifolium, L. lanceolatum), one sexual tetraploid species (L. vulgare) and two apomict tetraploid species thought to be related (L. dodartii, L. multiflorum). The extent of morphological differentiation between these species was assessed using ten diagnostic morphometric characters. RESULTS A discriminant analysis using the morphometric variables reliably assigns individuals into their respective species groups. We found that only modest genetic and epigenetic differentiation was revealed between species by Methylation Sensitive Amplification Polymorphism (MSAP). However, whilst there was little separation possible between ploidy levels on the basis of genetic profiles, there was clear and pronounced interploidy discrimination on the basis of epigenetic profiles. Here we investigate the relative contribution of genetic and epigenetic factors in explaining the complex phenotypic variability seen in problematic taxonomic groups such as Limonium that operate both apomixis and sexual modes of reproduction. CONCLUSIONS Our results suggest that epigenetic variation might be one of the drivers of the phenotypic divergence between diploid and tetraploid taxa and discuss that intergenome silencing offers a plausible mechanistic explanation for the observed phenotypic divergence between these microspecies. These results also suggest that epigenetic profiling offer an additional tool to infer ploidy level in stored specimens and that stable epigenetic change may play an important role in apomict evolution and species recognition.
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Affiliation(s)
- Ana Sofia Róis
- Plant Diversity and Conservation Group, Centro de Botânica Aplicada à Agricultura (CBAA), Instituto Superior de Agronomia (ISA), Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Carlos M Rodríguez López
- Plant Genomics Centre, School of Agriculture, Food and Wine, Faculty of Sciences, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA 5064 Australia
| | - Ana Cortinhas
- Plant Diversity and Conservation Group, Centro de Botânica Aplicada à Agricultura (CBAA), Instituto Superior de Agronomia (ISA), Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Matthias Erben
- Section Biodiversity Research & Systematic Botany, Maximilian University of Munich, Munich, Germany
| | - Dalila Espírito-Santo
- Plant Diversity and Conservation Group, Centro de Botânica Aplicada à Agricultura (CBAA), Instituto Superior de Agronomia (ISA), Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
- Research Network in Biodiversity and Evolutionary Biology (InBIO), ISA, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Michael J Wilkinson
- Plant Genomics Centre, School of Agriculture, Food and Wine, Faculty of Sciences, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA 5064 Australia
| | - Ana D Caperta
- Plant Diversity and Conservation Group, Centro de Botânica Aplicada à Agricultura (CBAA), Instituto Superior de Agronomia (ISA), Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
- Research Network in Biodiversity and Evolutionary Biology (InBIO), ISA, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
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12
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Tricker PJ, Rodríguez López CM, Hadley P, Wagstaff C, Wilkinson MJ. Pre-conditioning the epigenetic response to high vapor pressure deficit increases the drought tolerance of Arabidopsis thaliana. Plant Signal Behav 2013; 8:25974. [PMID: 24270688 PMCID: PMC4091208 DOI: 10.4161/psb.25974] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 07/30/2013] [Accepted: 07/31/2013] [Indexed: 05/22/2023]
Abstract
Epigenetic modification of the genome via cytosine methylation is a dynamic process that responds to changes in the growing environment. This modification can also be heritable. The combination of both properties means that there is the potential for the life experiences of the parental generation to modify the methylation profiles of their offspring and so potentially to “pre-condition” them to better accommodate abiotic conditions encountered by their parents. We recently identified high vapor pressure deficit (vpd)-induced DNA methylation at 2 gene loci in the stomatal development pathway and an associated reduction in leaf stomatal frequency.1 Here, we test whether this epigenetic modification pre-conditioned parents and their offspring to the more severe water stress of periodic drought. We found that 3 generations of high vpd-grown plants were better able to withstand periodic drought stress over 2 generations. This resistance was not directly associated with de novo methylation of the target stomata genes, but was associated with the cmt3 mutant’s inability to maintain asymmetric sequence context methylation. If our finding applies widely, it could have significant implications for evolutionary biology and breeding for stressful environments.
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Affiliation(s)
- Penny J Tricker
- School of Biological Sciences; University of Reading; Whiteknights; Reading, UK
| | - Carlos M Rodríguez López
- Institute of Biological; Environmental and Rural Sciences; Edward Llywd Building; University of Aberystwyth; Aberystwyth, Ceredigion, UK
| | - P Hadley
- School of Biological Sciences; University of Reading; Whiteknights; Reading, UK
| | - C Wagstaff
- Department of Food and Nutritional Sciences; University of Reading; Whiteknights; Reading, UK
| | - Mike J Wilkinson
- Institute of Biological; Environmental and Rural Sciences; Edward Llywd Building; University of Aberystwyth; Aberystwyth, Ceredigion, UK
- Correspondence to: Mike J Wilkinson,
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13
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Tricker PJ, Rodríguez López CM, Gibbings G, Hadley P, Wilkinson MJ. Transgenerational, dynamic methylation of stomata genes in response to low relative humidity. Int J Mol Sci 2013; 14:6674-89. [PMID: 23531533 PMCID: PMC3645660 DOI: 10.3390/ijms14046674] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 03/09/2013] [Accepted: 03/18/2013] [Indexed: 12/23/2022] Open
Abstract
Transgenerational inheritance of abiotic stress-induced epigenetic modifications in plants has potential adaptive significance and might condition the offspring to improve the response to the same stress, but this is at least partly dependent on the potency, penetrance and persistence of the transmitted epigenetic marks. We examined transgenerational inheritance of low Relative Humidity-induced DNA methylation for two gene loci in the stomatal developmental pathway in Arabidopsis thaliana and the abundance of associated short-interfering RNAs (siRNAs). Heritability of low humidity-induced methylation was more predictable and penetrative at one locus (SPEECHLESS, entropy ≤ 0.02; χ2 < 0.001) than the other (FAMA, entropy ≤ 0.17; χ2 ns). Methylation at SPEECHLESS correlated positively with the continued presence of local siRNAs (r2 = 0.87; p = 0.013) which, however, could be disrupted globally in the progeny under repeated stress. Transgenerational methylation and a parental low humidity-induced stomatal phenotype were heritable, but this was reversed in the progeny under repeated treatment in a previously unsuspected manner.
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Affiliation(s)
- Penny J. Tricker
- School of Biological Sciences, Philip Lyle Building, University of Reading, Whiteknights, Reading RG6 6BX, UK; E-Mails: (G.G.); (P.H.)
| | - Carlos M. Rodríguez López
- Institute of Biological, Environmental and Rural Sciences, Edward Llywd Building, University of Aberystwyth, Aberystwyth, Ceredigion SY23 3DA, UK
| | - George Gibbings
- School of Biological Sciences, Philip Lyle Building, University of Reading, Whiteknights, Reading RG6 6BX, UK; E-Mails: (G.G.); (P.H.)
| | - Paul Hadley
- School of Biological Sciences, Philip Lyle Building, University of Reading, Whiteknights, Reading RG6 6BX, UK; E-Mails: (G.G.); (P.H.)
| | - Mike J. Wilkinson
- Institute of Biological, Environmental and Rural Sciences, Edward Llywd Building, University of Aberystwyth, Aberystwyth, Ceredigion SY23 3DA, UK
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +61-(0)8-8313-1532; Fax: +61-(0)8-8303-7102
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14
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López CMR, Lloyd AJ, Leonard K, Wilkinson MJ. Differential effect of three base modifications on DNA thermostability revealed by high resolution melting. Anal Chem 2012; 84:7336-42. [PMID: 22882125 DOI: 10.1021/ac301459x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
High resolution melting (HRM) can detect and quantify the presence of 5-methylcytosine (5mC) in DNA samples, but the ability of HRM to diagnose other DNA modifications remains unexplored. The DNA bases N6-methyladenine and 5-hydroxymethylcytosine occur across almost all phyla. While their function remains controversial, their presence perturbs DNA structure. Such modifications could affect gene regulation, chromatin condensation and DNA packaging. Here, we reveal that DNA containing N6-methyladenine or 5-hydroxymethylcytosine exhibits reduced thermal stability compared to cytosine-methylated DNA. These thermostability changes are sufficiently divergent to allow detection and quantification by HRM analysis. Thus, we report that HRM distinguishes between sequence-identical DNA differing only in the modification type of one base. This approach is also able to distinguish between two DNA fragments carrying both N6-methyladenine and 5-methylcytosine but differing only in the distance separating the modified bases. This finding provides scope for the development of new methods to characterize DNA chemically and to allow for low cost screening of mutant populations of genes involved in base modification. More fundamentally, contrast between the thermostabilizing effects of 5mC on dsDNA compared with the destabilizing effects of N6-methyladenine (m6A) and 5-hydroxymethylcytosine (5hmC) raises the intriguing possibility of an antagonistic relationship between modification types with functional significance.
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Affiliation(s)
- Carlos M Rodríguez López
- Aberystwyth University, IBERS, Institute of Biological, Environmental and Rural Sciences, Aberystwyth, Wales, UK
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15
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Tricker PJ, Gibbings JG, Rodríguez López CM, Hadley P, Wilkinson MJ. Low relative humidity triggers RNA-directed de novo DNA methylation and suppression of genes controlling stomatal development. J Exp Bot 2012; 63:3799-813. [PMID: 22442411 PMCID: PMC3733579 DOI: 10.1093/jxb/ers076] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 02/08/2012] [Accepted: 02/15/2012] [Indexed: 05/18/2023]
Abstract
Environmental cues influence the development of stomata on the leaf epidermis, and allow plants to exert plasticity in leaf stomatal abundance in response to the prevailing growing conditions. It is reported that Arabidopsis thaliana 'Landsberg erecta' plants grown under low relative humidity have a reduced stomatal index and that two genes in the stomatal development pathway, SPEECHLESS and FAMA, become de novo cytosine methylated and transcriptionally repressed. These environmentally-induced epigenetic responses were abolished in mutants lacking the capacity for de novo DNA methylation, for the maintenance of CG methylation, and in mutants for the production of short-interfering non-coding RNAs (siRNAs) in the RNA-directed DNA methylation pathway. Induction of methylation was quantitatively related to the induction of local siRNAs under low relative humidity. Our results indicate the involvement of both transcriptional and post-transcriptional gene suppression at these loci in response to environmental stress. Thus, in a physiologically important pathway, a targeted epigenetic response to a specific environmental stress is reported and several of its molecular, mechanistic components are described, providing a tractable platform for future epigenetics experiments. Our findings suggest epigenetic regulation of stomatal development that allows for anatomical and phenotypic plasticity, and may help to explain at least some of the plant's resilience to fluctuating relative humidity.
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Affiliation(s)
- Penny J. Tricker
- School of Biological Sciences, Philip Lyle Building, University of Reading, Whiteknights, Reading RG6 6BX, UK
| | - J. George Gibbings
- School of Biological Sciences, Philip Lyle Building, University of Reading, Whiteknights, Reading RG6 6BX, UK
| | - Carlos M. Rodríguez López
- Institute of Biological, Environmental and Rural Sciences, Edward Llywd Building, University of Aberystwyth, Aberystwyth, Ceredigion SY23 3DA, UK
| | - Paul Hadley
- School of Biological Sciences, Philip Lyle Building, University of Reading, Whiteknights, Reading RG6 6BX, UK
| | - Mike J. Wilkinson
- Institute of Biological, Environmental and Rural Sciences, Edward Llywd Building, University of Aberystwyth, Aberystwyth, Ceredigion SY23 3DA, UK
- To whom correspondence should be addressed. E-mail:
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Rodríguez López CM, Morán P, Lago F, Espiñeira M, Beckmann M, Consuegra S. Detection and quantification of tissue of origin in salmon and veal products using methylation sensitive AFLPs. Food Chem 2012. [DOI: 10.1016/j.foodchem.2011.09.120] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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17
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Rodríguez López CM, Guzmán Asenjo B, Lloyd AJ, Wilkinson MJ. Direct detection and quantification of methylation in nucleic acid sequences using high-resolution melting analysis. Anal Chem 2010; 82:9100-8. [PMID: 20945868 DOI: 10.1021/ac1024057] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
High-resolution melting (HRM) analysis exploits the reduced thermal stability of DNA fragments that contain base mismatches to detect single nucleotide polymorphisms (SNPs). However, the capacity of HRM to reveal other features of DNA chemistry remains unexplored. DNA methylation plays a key role in regulating gene expression and is essential for normal development in many higher organisms. The presence of methylated bases perturbs the double-stranded DNA structure, although its effect on DNA thermal stability is largely unknown. Here, we reveal that methylated DNA has enhanced thermal stability and is sufficiently divergent from nonmethylated DNA to allow detection and quantification by HRM analysis. This approach reliably distinguishes between sequence-identical DNA differing only in the methylation of one base. The method also provides accurate discrimination between mixes of methylated and nonmethylated DNAs, allowing discrimination between DNA that is 1% and 0% methylated and also between 97.5% and 100% methylated. Thus, the method provides a new means of adjusting thermal optima for DNA hybridization and PCR-based techniques and to empirically measure the impact of DNA methylation marks on the thermostability of regulatory regions. In the longer term, it could enable the development of new techniques to quantify methylated DNA.
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Affiliation(s)
- Carlos M Rodríguez López
- Aberystwyth University, IBERS-Institute of Biological, Environmental and Rural Sciences, Aberystwyth, Wales, SY23 3DA, UK
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Rodríguez López CM, Wetten AC, Wilkinson MJ. Progressive erosion of genetic and epigenetic variation in callus-derived cocoa (Theobroma cacao) plants. New Phytol 2010; 186:856-868. [PMID: 20406408 DOI: 10.1111/j.1469-8137.2010.03242.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
*Relatively little is known about the timing of genetic and epigenetic forms of somaclonal variation arising from callus growth. We surveyed for both types of change in cocoa (Theobroma cacao) plants regenerated from calli of various ages, and also between tissues from the source trees. *For genetic change, we used 15 single sequence repeat (SSR) markers from four source trees and from 233 regenerated plants. For epigenetic change, we used 386 methylation-sensitive amplified polymorphism (MSAP) markers on leaf and explant (staminode) DNA from two source trees and on leaf DNA from 114 regenerants. *Genetic variation within source trees was limited to one slippage mutation in one leaf. Regenerants were far more variable, with 35% exhibiting at least one mutation. Genetic variation initially accumulated with culture age but subsequently declined. MSAP (epigenetic) profiles diverged between leaf and staminode samples from source trees. Multivariate analysis revealed that leaves from regenerants occupied intermediate eigenspace between leaves and staminodes of source plants but became progressively more similar to source tree leaves with culture age. *Statistical analysis confirmed this rather counterintuitive finding that leaves of 'late regenerants' exhibited significantly less genetic and epigenetic divergence from source leaves than those exposed to short periods of callus growth.
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Affiliation(s)
- Carlos M Rodríguez López
- Institute of Biological, Environmental & Rural Sciences, Aberystwyth University Penglais, Aberystwyth, Wales, UK, SY23 3DA
| | - Andrew C Wetten
- School of Biological Sciences, Harborne Building, University of Reading, Whiteknights, Reading, Berkshire, RG6 6AS, UK
| | - Michael J Wilkinson
- Institute of Biological, Environmental & Rural Sciences, Aberystwyth University Penglais, Aberystwyth, Wales, UK, SY23 3DA
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Rodríguez López CM, Wetten AC, Wilkinson MJ. Detection and quantification of in vitro-culture induced chimerism using simple sequence repeat (SSR) analysis in Theobroma cacao (L.). Theor Appl Genet 2004; 110:157-166. [PMID: 15678329 DOI: 10.1007/s00122-004-1823-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2004] [Accepted: 09/22/2004] [Indexed: 05/24/2023]
Abstract
Mutation rates are often elevated in plants regenerated from in vitro culture, giving rise to so-called 'somaclonal variation'. Detailed characterisation of mutation profiles that arise during culture should improve our understanding of processes influencing mutation and allow the selection of protocols yielding the fewest/least severe changes. Somatic mutations will usually produce genetic chimeras where unchanged alleles are retained by some cells. Such chimeras are difficult to detect but likely to form a significant proportion of any regenerant population. We present a simple protocol that enables the provisional diagnosis of both homogenous and chimeric mutants among large regenerant populations, together with a semi-quantitative means of estimating the proportion of mutant cells. The assay exploits consistent differential amplification of alternate simple sequence repeat alleles at heterozygous loci. Calibration of the relative amplification of alleles from two genotypes-and the synthetic chimeras created from them-revealed a strong linear relationship between 'peak heights' representing alternate alleles following capillary electrophoresis. The assay predicts chimeric composition to a reasonable level of confidence (+/-5%) so long as the infrequent allele exceeds 15% of the template. The system was applied to 233 regenerants of cocoa somatic embryogenesis and identified 72 (31%) putative chimeric mutants for slippage mutation or allele loss across two loci.
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