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Deb SK, Edger PP, Pires JC, McKain MR. Patterns, mechanisms, and consequences of homoeologous exchange in allopolyploid angiosperms: a genomic and epigenomic perspective. THE NEW PHYTOLOGIST 2023; 238:2284-2304. [PMID: 37010081 DOI: 10.1111/nph.18927] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 03/16/2023] [Indexed: 05/19/2023]
Abstract
Allopolyploids result from hybridization between different evolutionary lineages coupled with genome doubling. Homoeologous chromosomes (chromosomes with common shared ancestry) may undergo recombination immediately after allopolyploid formation and continue over successive generations. The outcome of this meiotic pairing behavior is dynamic and complex. Homoeologous exchanges (HEs) may lead to the formation of unbalanced gametes, reduced fertility, and selective disadvantage. By contrast, HEs could act as sources of novel evolutionary substrates, shifting the relative dosage of parental gene copies, generating novel phenotypic diversity, and helping the establishment of neo-allopolyploids. However, HE patterns vary among lineages, across generations, and even within individual genomes and chromosomes. The causes and consequences of this variation are not fully understood, though interest in this evolutionary phenomenon has increased in the last decade. Recent technological advances show promise in uncovering the mechanistic basis of HEs. Here, we describe recent observations of the common patterns among allopolyploid angiosperm lineages, underlying genomic and epigenomic features, and consequences of HEs. We identify critical research gaps and discuss future directions with far-reaching implications in understanding allopolyploid evolution and applying them to the development of important phenotypic traits of polyploid crops.
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Affiliation(s)
- Sontosh K Deb
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
- Department of Forestry and Environmental Science, Shahjalal University of Science and Technology, Sylhet, 3114, Bangladesh
| | - Patrick P Edger
- Department of Horticulture, Michigan State University, East Lansing, MI, 48823, USA
- Genetics and Genome Sciences Program, Michigan State University, East Lansing, MI, 48823, USA
| | - J Chris Pires
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Michael R McKain
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
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2
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Shahzad K, Zhang X, Zhang M, Guo L, Qi T, Tang H, Wang H, Mubeen I, Qiao X, Peng R, Wu J, Xing C. Homoeolog gene expression analysis reveals novel expression biases in upland hybrid cotton under intraspecific hybridization. Funct Integr Genomics 2022; 22:757-768. [PMID: 35771309 DOI: 10.1007/s10142-022-00877-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hybridization is useful to enhance the yield potential of agronomic crops in the world. Cotton has genome doubling due to the allotetraploid process and hybridization in coordination with duplicated genome can produce more yield and adaptability. Therefore, the expression of homoeologous gene pairs between hybrids and inbred parents is vital to characterize the genetic source of heterosis in cotton. Investigation results of homoeolog gene pairs between two contrasting hybrids and their respective inbred parents identified 36853 homoeolog genes in hybrids. It was observed both high and low hybrids had similar trends in homoeolog gene expression patterns in each tissue under study. An average of 96% of homoeolog genes had no biased expression and their expressions were derived from the equal contribution of both parents. Besides, very few homoeolog genes (an average of 1%) showed no biased or novel expression in both hybrids. The functional analysis described secondary metabolic pathways had a majority of novel biased homoeolog genes in hybrids. These results contribute preliminary knowledge about how hybridization affects expression patterns of homoeolog gene pairs in upland cotton hybrids. Our study also highlights the functional genomics of metabolic genes to explore the genetic mechanism of heterosis in cotton.
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Affiliation(s)
- Kashif Shahzad
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China
| | - Xuexian Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China.,Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China
| | - Meng Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China.,Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China
| | - Liping Guo
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China.,Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China
| | - Tingxiang Qi
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China.,Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China
| | - Huini Tang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China.,Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China
| | - Hailin Wang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China
| | - Iqra Mubeen
- Department of Biochemistry, University of Agriculture, Faisalabad, 38040, Pakistan
| | - Xiuqin Qiao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China
| | - Renhai Peng
- Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China. .,College of Biology and Food Engineering, Anyang Institute of Technology, Anyang, 455000, Henan, China.
| | - Jianyong Wu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China. .,Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China.
| | - Chaozhu Xing
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture and Rural Affairs, 38 Huanghe Dadao, Anyang, 455000, Henan, China. .,Research Base, Anyang Institute of Technology, State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China.
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Analysis of Transcriptional Changes in Different Brassica napus Synthetic Allopolyploids. Genes (Basel) 2021; 12:genes12010082. [PMID: 33440604 PMCID: PMC7827416 DOI: 10.3390/genes12010082] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/28/2020] [Accepted: 01/04/2021] [Indexed: 11/23/2022] Open
Abstract
Allopolyploidy is an evolutionary and mechanistically intriguing process involving the reconciliation of two or more sets of diverged genomes and regulatory interactions, resulting in new phenotypes. In this study, we explored the gene expression patterns of eight F2 synthetic Brassica napus using RNA sequencing. We found that B. napus allopolyploid formation was accompanied by extensive changes in gene expression. A comparison between F2 and the parent shows a certain proportion of differentially expressed genes (DEG) and activation\silent gene, and the two genomes (female parent (AA)\male parent (CC) genomes) showed significant differences in response to whole-genome duplication (WGD); non-additively expressed genes represented a small portion, while Gene Ontology (GO) enrichment analysis showed that it played an important role in responding to WGD. Besides, genome-wide expression level dominance (ELD) was biased toward the AA genome, and the parental expression pattern of most genes showed a high degree of conservation. Moreover, gene expression showed differences among eight individuals and was consistent with the results of a cluster analysis of traits. Furthermore, the differential expression of waxy synthetic pathways and flowering pathway genes could explain the performance of traits. Collectively, gene expression of the newly formed allopolyploid changed dramatically, and this was different among the selfing offspring, which could be a prominent cause of the trait separation. Our data provide novel insights into the relationship between the expression of differentially expressed genes and trait segregation and provide clues into the evolution of allopolyploids.
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Liu Z, Wang R, Wang J. Comprehensive Transcriptomic Analysis for Developing Seeds of a Synthetic Brassica Hexaploid. PLANTS (BASEL, SWITZERLAND) 2020; 9:E1141. [PMID: 32899324 PMCID: PMC7570109 DOI: 10.3390/plants9091141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 01/10/2023]
Abstract
Polyploidization is a universal phenomenon in plants and plays a crucial role in evolution. In this study, the transcriptomes of developing seeds of a synthetic Brassica hexaploid and its parents (B. rapa and B. carinata) were analyzed to find the gene expression changes in hexaploid seeds. There were 3166 and 3893 DEGs between the Brassica hexaploid and its parents at the full-size stage and mature stage, respectively, most of which were upregulated in hexaploid seeds compared to its parents. At the mature stage, the hexaploid seeds showed a greater difference from its parents. These DEGs had a wide range of functions, which may account for the physiological and morphological differences between the Brassica hexaploid and its parents. The KEGG pathway analysis revealed that hexaploid seeds had higher levels of expression of genes involved in metabolic pathways, RNA transport and biosynthesis of secondary metabolites, and the expression levels in the photosynthesis-related pathways were significantly higher than those in B. rapa. Transgressive expression was the main non-additive expression pattern of the Brassica hexaploid. The gene expression difference between the Brassica hexaploid and its paternal parent was more significant than that with its maternal parent, which may be due in part to the cytoplasmic and maternal effects. Moreover, transcription factor genes, such as G2-like, MYB and mTERF, were highly expressed in hexaploid seeds, possibly promoting their resistance to stress. Our results may provide valuable insights into the adaptation mechanisms of polyploid plants.
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Affiliation(s)
| | | | - Jianbo Wang
- College of Life Sciences, Wuhan University, Wuhan 430072, China; (Z.L.); (R.W.)
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Li M, Wang R, Wu X, Wang J. Homoeolog expression bias and expression level dominance (ELD) in four tissues of natural allotetraploid Brassica napus. BMC Genomics 2020; 21:330. [PMID: 32349676 PMCID: PMC7191788 DOI: 10.1186/s12864-020-6747-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 04/21/2020] [Indexed: 01/01/2023] Open
Abstract
Background Allopolyploidy is widespread in angiosperms, and they can coordinate two or more different genomes through genetic and epigenetic modifications to exhibit stronger vigor and adaptability. To explore the changes in homologous gene expression patterns in the natural allotetraploid Brassica napus (AnAnCnCn) relative to its two diploid progenitors, B. rapa (ArAr) and B. oleracea (CoCo), after approximately 7500 years of domestication, the global gene pair expression patterns in four major tissues (stems, leaves, flowers and siliques) of these three species were analyzed using an RNA sequencing approach. Results The results showed that the ‘transcriptomic shock’ phenomenon was alleviated in natural B. napus after approximately 7500 years of natural domestication, and most differentially expressed genes (DEGs) in B. napus were downregulated relative to those in its two diploid progenitors. The KEGG analysis indicated that three pathways related to photosynthesis were enriched in both comparison groups (AnAnCnCn vs ArAr and AnAnCnCn vs CoCo), and these pathways were all downregulated in four tissues of B. napus. In addition, homoeolog expression bias and expression level dominance (ELD) in B. napus were thoroughly studied through analysis of expression levels of 27,609 B. rapa-B. oleracea orthologous gene pairs. The overwhelming majority of gene pairs (an average of 86.7%) in B. napus maintained their expression pattern in two diploid progenitors, and approximately 78.1% of the gene pairs showed expression bias with a preference toward the A subgenome. Overall, an average of 48, 29.7 and 22.3% homologous gene pairs exhibited additive expression, ELD and transgressive expression in B. napus, respectively. The ELD bias varies from tissue to tissue; specifically, more gene pairs in stems and siliques showed ELD-A, whereas the opposite was observed in leaves and flowers. More transgressive upregulation, rather than downregulation, was observed in gene pairs of B. napus. Conclusions In general, these results may provide a comprehensive understanding of the changes in homologous gene expression patterns in natural B. napus after approximately 7500 years of evolution and domestication and may enhance our understanding of allopolyploidy.
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Affiliation(s)
- Mengdi Li
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Ruihua Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xiaoming Wu
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Oil Crops Research Institute of CAAS, Wuhan, 430062, China
| | - Jianbo Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
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McCarthy EW, Landis JB, Kurti A, Lawhorn AJ, Chase MW, Knapp S, Le Comber SC, Leitch AR, Litt A. Early consequences of allopolyploidy alter floral evolution in Nicotiana (Solanaceae). BMC PLANT BIOLOGY 2019; 19:162. [PMID: 31029077 PMCID: PMC6486959 DOI: 10.1186/s12870-019-1771-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 04/10/2019] [Indexed: 05/08/2023]
Abstract
BACKGROUND Polyploidy has played a major role in angiosperm evolution. Previous studies have examined polyploid phenotypes in comparison to their extant progenitors, but not in context of predicted progenitor phenotypes at allopolyploid origin. In addition, differences in the trends of polyploid versus diploid evolution have not been investigated. We use ancestral character-state reconstructions to estimate progenitor phenotype at allopolyploid origin to determine patterns of polyploid evolution leading to morphology of the extant species. We also compare trends in diploid versus allopolyploid evolution to determine if polyploidy modifies floral evolutionary patterns. RESULTS Predicting the ancestral phenotype of a nascent allopolyploid from reconstructions of diploid phenotypes at the time of polyploid formation generates different phenotype predictions than when extant diploid phenotypes are used, the outcome of which can alter conclusions about polyploid evolution; however, most analyses yield the same results. Using ancestral reconstructions of diploid floral phenotypes indicate that young polyploids evolve shorter, wider corolla tubes, but older polyploids and diploids do not show any detectable evolutionary trends. Lability of the traits examined (floral shape, corolla tube length, and corolla tube width) differs across young and older polyploids and diploids. Corolla length is more evolutionarily labile in older polyploids and diploids. Polyploids do not display unique suites of floral characters based on both morphological and color traits, but some suites of characters may be evolving together and seem to have arisen multiple times within Nicotiana, perhaps due to the influence of pollinators. CONCLUSIONS Young polyploids display different trends in floral evolution (shorter, wider corolla tubes, which may result in more generalist pollination) than older polyploids and diploids, suggesting that patterns of divergence are impacted by the early consequences of allopolyploidy, perhaps arising from genomic shock and/or subsequent genome stabilization associated with diploidization. Convergent evolution in floral morphology and color in Nicotiana can be consistent with pollinator preferences, suggesting that pollinators may have shaped floral evolution in Nicotiana.
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Affiliation(s)
- Elizabeth W. McCarthy
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521 USA
- Present address: Department of Biological Sciences, SUNY Cortland, Cortland, NY 13045 USA
| | - Jacob B. Landis
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521 USA
- Department of Biology, University of Florida, Gainesville, FL 32611 USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611 USA
| | - Amelda Kurti
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521 USA
| | - Amber J. Lawhorn
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521 USA
| | - Mark W. Chase
- Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS UK
- Department of Environment and Agriculture, Curtin University, Bentley, Western Australia 6102 Australia
| | | | - Steven C. Le Comber
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS UK
| | - Andrew R. Leitch
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS UK
| | - Amy Litt
- Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521 USA
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Long YL, Qiao F, Jiang XF, Cong HQ, Sun ML, Xu ZJ. Screening and analysis on the differentially expression genes between diploid and autotetraploid watermelon by using of digital gene expression profile. BRAZ J BIOL 2019; 79:180-190. [DOI: 10.1590/1519-6984.174475] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 12/27/2017] [Indexed: 11/22/2022] Open
Abstract
Abstract Synthetic polyploids are key breeding materials for watermelon. Compared with diploid watermelon, the tetraploid watermelon often exhibit wide phenotypic differences and differential gene expression. Digital gene expression (DGE) profile technique was performed in this study to present gene expression patterns in an autotetraploid and its progenitor diploid watermelon, and deferentially expressed genes (DEGs) related to the abiotic and biotic stress were also addressed. Altogether, 4,985 DEGs were obtained in the autotetraploid against its progenitor diploid, and 66.02% DEGs is up-regulated. GO analysis shows that these DEGs mainly distributed in ‘metabolic process’, ‘cell’ and ‘catalytic activity’. KEGG analysis revealed that these DEGs mainly cover ‘metabolic pathways’, ‘secondary metabolites’ and ‘ribosome’. Moreover, 134 tolerance related DEGs were identified which cover osmotic adjustment substance, protective enzymes/protein, signaling proteins and pathogenesis-related proteins. This study present the differential expression of stress related genes and global gene expression patterns at background level in autotetraploid watermelons. These new evidences could supplement the molecular theoretical basis for the better resistance after the genome doubling in the gourd family.
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Affiliation(s)
- Y. L. Long
- Hainan University, China; Chinese Academy of Tropical Agricultural Sciences, China
| | - F. Qiao
- Chinese Academy of Tropical Agricultural Sciences, China
| | | | - H. Q. Cong
- Chinese Academy of Tropical Agricultural Sciences, China
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Wu J, Lin L, Xu M, Chen P, Liu D, Sun Q, Ran L, Wang Y. Homoeolog expression bias and expression level dominance in resynthesized allopolyploid Brassica napus. BMC Genomics 2018; 19:586. [PMID: 30081834 PMCID: PMC6080508 DOI: 10.1186/s12864-018-4966-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 07/30/2018] [Indexed: 01/08/2023] Open
Abstract
Background Allopolyploids require rapid genetic and epigenetic modifications to reconcile two or more sets of divergent genomes. To better understand the fate of duplicate genes following genomic mergers and doubling during allopolyploid formation, in this study, we explored the global gene expression patterns in resynthesized allotetraploid Brassica napus (AACC) and its diploid parents B. rapa (AA) and B. oleracea (CC) using RNA sequencing of leaf transcriptomes. Results We found that allopolyploid B. napus formation was accompanied by extensive changes (approximately one-third of the expressed genes) in the parental gene expression patterns (‘transcriptome shock’). Interestingly, the majority (85%) of differentially expressed genes (DEGs) were downregulated in the allotetraploid. Moreover, the homoeolog expression bias (relative contribution of homoeologs to the transcriptome) and expression level dominance (total expression level of both homoeologs) were thoroughly investigated by monitoring the expression of 23,766 B. oleracea-B. rapa orthologous gene pairs. Approximately 36.5% of the expressed gene pairs displayed expression bias with a slight preference toward the A-genome. In addition, 39.6, 4.9 and 9.0% of the expressed gene pairs exhibited expression level dominance (ELD), additivity expression and transgressive expression, respectively. The genome-wide ELD was also biased toward the A-genome in the resynthesized B. napus. To explain the ELD phenomenon, we compared the individual homoeolog expression levels relative to those of the diploid parents and found that ELD in the direction of the higher-expression parent can be explained by the downregulation of homoeologs from the dominant parent or upregulation of homoeologs from the nondominant parent; however, ELD in the direction of the lower-expression parent can be explained only by the downregulation of the nondominant parent or both homoeologs. Furthermore, Gene Ontology (GO) enrichment analysis suggested that the alteration in the gene expression patterns could be a prominent cause of the phenotypic variation between the newly formed B. napus and its parental species. Conclusions Collectively, our data provide insight into the rapid repatterning of gene expression at the beginning of Brassica allopolyploidization and enhance our knowledge of allopolyploidization processes. Electronic supplementary material The online version of this article (10.1186/s12864-018-4966-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jian Wu
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China
| | - Li Lin
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China
| | - Meiling Xu
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China
| | - Peipei Chen
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China
| | - Dongxiao Liu
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China
| | - Qinfu Sun
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China
| | - Liping Ran
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China
| | - Youping Wang
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China.
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Li W, Liu J, Tan H, Luo L, Cui J, Hu J, Wang S, Liu Q, Hu F, Tang C, Ren L, Yang C, Zhao R, Tao M, Zhang C, Qin Q, Liu S. Asymmetric expression patterns reveal a strong maternal effect and dosage compensation in polyploid hybrid fish. BMC Genomics 2018; 19:517. [PMID: 29969984 PMCID: PMC6030793 DOI: 10.1186/s12864-018-4883-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/19/2018] [Indexed: 03/05/2023] Open
Abstract
Background Hybridization and polyploidization are regarded as the major driving forces in plant speciation, diversification, and ecological adaptation. Our knowledge regarding the mechanisms of duplicated-gene regulation following genomic merging or doubling is primarily derived from plants and is sparse for vertebrates. Results We successfully obtained an F1 generation (including allodiploid hybrids and triploid hybrids) from female Megalobrama amblycephala Yih (BSB, 2n = 48) × male Xenocypri davidi Bleeker (YB, 2n = 48). The duplicated-gene expression patterns of the two types of hybrids were explored using RNA-Seq data. In total, 5.44 × 108 (69.32 GB) clean reads and 499,631 assembled unigenes were obtained from the testis transcriptomes. The sequence similarity analysis of 4265 orthologs revealed that the merged genomes were dominantly expressed in different ploidy hybrids. The differentially expressed genes in the two types of hybrids were asymmetric compared with those in both parents. Furthermore, the genome-wide expression level dominance (ELD) was biased toward the maternal BSB genome in both the allodiploid and triploid hybrids. In addition, the dosage-compensation mechanisms that reduced the triploid expression levels to the diploid state were determined in the triploid hybrids. Conclusions Our results indicate that divergent genomes undergo strong interactions and domination in allopolyploid offspring. Genomic merger has a greater effect on the gene-expression patterns than genomic doubling. The various expression mechanisms (including maternal effect and dosage compensation) in different ploidy hybrids suggest that the initial genomic merger and doubling play important roles in polyploidy adaptation and evolution. Electronic supplementary material The online version of this article (10.1186/s12864-018-4883-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wuhui Li
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Junmei Liu
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Hui Tan
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Lingling Luo
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Jialin Cui
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Jie Hu
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Shi Wang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Qingfeng Liu
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Fangzhou Hu
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Chenchen Tang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Li Ren
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Conghui Yang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Rurong Zhao
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Min Tao
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Chun Zhang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Qinbo Qin
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China.,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China
| | - Shaojun Liu
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal university, Changsha, 410081, Hunan, People's Republic of China. .,College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China.
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10
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Kalinka A, Achrem M. Reorganization of wheat and rye genomes in octoploid triticale (× Triticosecale). PLANTA 2018; 247:807-829. [PMID: 29234880 PMCID: PMC5856900 DOI: 10.1007/s00425-017-2827-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/03/2017] [Indexed: 06/01/2023]
Abstract
The analysis of early generations of triticale showed numerous rearrangements of the genome. Complexed transformation included loss of chromosomes, t-heterochromatin content changes and the emergence of retrotransposons in new locations. This study investigated certain aspects of genomic transformations in the early generations (F5 and F8) of the primary octoploid triticale derived from the cross of hexaploid wheat with the diploid rye. Most of the plants tested were hypoploid; among eliminated chromosomes were rye chromosomes 4R and 5R and variable number of wheat chromosomes. Wheat chromosomes were eliminated to a higher extent. The lower content of telomeric heterochromatin was also found in rye chromosomes in comparison with parental rye. Studying the location of selected retrotransposons from Ty1-copia and Ty3-gypsy families using fluorescence in situ hybridization revealed additional locations of these retrotransposons that were not present in chromosomes of parental species. ISSR, IRAP and REMAP analyses showed significant changes at the level of specific DNA nucleotide sequences. In most cases, the disappearance of certain types of bands was observed, less frequently new types of bands appeared, not present in parental species. This demonstrates the scale of genome rearrangement and, above all, the elimination of wheat and rye sequences, largely due to the reduction of chromosome number. With regard to the proportion of wheat to rye genome, the rye genome was more affected by the changes, thus this study was focused more on the rye genome. Observations suggest that genome reorganization is not finished in the F5 generation but is still ongoing in the F8 generation.
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Affiliation(s)
- Anna Kalinka
- Department of Cell Biology, Faculty of Biology, Institute for Research on Biodiversity, University of Szczecin, Wąska 13, 71-415, Szczecin, Poland
- Faculty of Biology, Molecular Biology and Biotechnology Center, University of Szczecin, Wąska 13, 71-415, Szczecin, Poland
| | - Magdalena Achrem
- Department of Cell Biology, Faculty of Biology, Institute for Research on Biodiversity, University of Szczecin, Wąska 13, 71-415, Szczecin, Poland.
- Faculty of Biology, Molecular Biology and Biotechnology Center, University of Szczecin, Wąska 13, 71-415, Szczecin, Poland.
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11
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Lloyd A, Blary A, Charif D, Charpentier C, Tran J, Balzergue S, Delannoy E, Rigaill G, Jenczewski E. Homoeologous exchanges cause extensive dosage-dependent gene expression changes in an allopolyploid crop. THE NEW PHYTOLOGIST 2018; 217:367-377. [PMID: 29034956 DOI: 10.1111/nph.14836] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Accepted: 08/02/2017] [Indexed: 05/22/2023]
Abstract
Structural variation is a major source of genetic diversity and an important substrate for selection. In allopolyploids, homoeologous exchanges (i.e. between the constituent subgenomes) are a very frequent type of structural variant. However, their direct impact on gene content and gene expression had not been determined. Here, we used a tissue-specific mRNA-Seq dataset to measure the consequences of homoeologous exchanges (HE) on gene expression in Brassica napus, a representative allotetraploid crop. We demonstrate that expression changes are proportional to the change in gene copy number triggered by the HEs. Thus, when homoeologous gene pairs have unbalanced transcriptional contributions before the HE, duplication of one copy does not accurately compensate for loss of the other and combined homoeologue expression also changes. These effects are, however, mitigated over time. This study sheds light on the origins, timing and functional consequences of homeologous exchanges in allopolyploids. It demonstrates that the interplay between new structural variation and the resulting impacts on gene expression, influences allopolyploid genome evolution.
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Affiliation(s)
- Andrew Lloyd
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles Cedex, 78000, France
| | - Aurélien Blary
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles Cedex, 78000, France
| | - Delphine Charif
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles Cedex, 78000, France
| | - Catherine Charpentier
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles Cedex, 78000, France
| | - Joseph Tran
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles Cedex, 78000, France
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, Orsay, 91405, France
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, Orsay, 91405, France
| | - Sandrine Balzergue
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, Orsay, 91405, France
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, Orsay, 91405, France
- IRHS, INRA, AGROCAMPUS-Ouest, Université d'Angers, SFR 4207 QUASAV, 42 rue Georges Morel, Beaucouzé cedex, 49071, France
| | - Etienne Delannoy
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, Orsay, 91405, France
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, Orsay, 91405, France
| | - Guillem Rigaill
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, Orsay, 91405, France
- Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, Orsay, 91405, France
- Laboratoire de Mathématiques et Modélisation d'Evry (LaMME), Université d'Evry Val d'Essonne, UMR CNRS 8071, ENSIIE, USC INRA, Évry Cedex, France
| | - Eric Jenczewski
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles Cedex, 78000, France
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12
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Suo Y, Min Y, Dong C, Wang Y, Cheng S, Kang X. MicroRNA expression changes following synthesis of three full-sib Populus triploid populations with different heterozygosities. PLANT MOLECULAR BIOLOGY 2017; 95:215-225. [PMID: 28884266 DOI: 10.1007/s11103-017-0627-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Through high-throughput sequencing, we compared the relative expression levels of miRNA in three full-sib Populus triploid populations with that in their parents and one diploid hybrid population. We found similar numbers of miRNAs differentially expressed between the parents and the four progeny hybrid populations. In addition, unbalanced parental expression level dominance of miRNAs were found in the three allotriploid and interspecific hybrid populations, which may reprogram gene expression networks and contribute to the growth of Populus hybrids. These results indicated that hybridization has a great impact on the miRNA expression variation in the newly synthesized Populus triploid and diploid hybrid populations. However, we also found no significant differences in miRNA expression among one diploid and three triploid hybrid populations, hinting that miRNA abundances do not increase with the genome content. No dosage effect of miRNA expression could lead to dosage-dependent negative effects on target genes and their downstream pathway in polyploids. We speculate that polyploids may gain advantages from the slight decrease in miRNA regulation, suggesting an important molecular mechanism of polyploid advantage. Hybridization with three types of induced 2n gametes transmitted different parental heterozygosities has been proven as an efficient method for Populus triploid production. Several researches have shown that miRNA could be non-additively expressed in allopolyploids. However, it is still unclear whether the non-additively expressed miRNAs result from the effect of hybridization or polyploidization, and whether a dose response to the additional genomic content exists for the expression of miRNA. Toward this end, through high-throughput sequencing, we compared the expression levels of miRNA in three full-sib Populus triploid populations with that in their parents and one interspecific hybrid population. We found similar numbers of miRNAs differentially expressed between the parents and the four progeny hybrid populations. Unbalanced parental expression level dominance of miRNAs were found in the three triploid and diploid hybrid populations, which may reprogram gene expression networks and affect the growth of Populus hybrids. These results indicated that hybridization has a great impact on the miRNA expression variation in the newly synthesized Populus triploid and diploid hybrid populations. However, we also found no significant differences in miRNA expression among the three triploid populations and the diploid hybrid population. No dosage effect of miRNA expression could lead to dosage-dependent negative effects on target genes and their downstream pathway in polyploids. We speculate that polyploids may gain advantages from the decrease in miRNA negative regulation, suggesting an important molecular mechanism of polyploid advantage.
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Affiliation(s)
- Yujing Suo
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
- Key Laboratory of Genetics and Breeding in Forest Tree and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
- China Paulownia Research Center, Zhengzhou, 450003, Henan, People's Republic of China
| | - Yu Min
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
- Key Laboratory of Genetics and Breeding in Forest Tree and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
| | - Chunbo Dong
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
- Key Laboratory of Genetics and Breeding in Forest Tree and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
| | - Yi Wang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
- Key Laboratory of Genetics and Breeding in Forest Tree and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
| | - Shiping Cheng
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
- Key Laboratory of Genetics and Breeding in Forest Tree and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
| | - Xiangyang Kang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China.
- Key Laboratory of Genetics and Breeding in Forest Tree and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China.
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13
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Carlson KD, Fernandez-Pozo N, Bombarely A, Pisupati R, Mueller LA, Madlung A. Natural variation in stress response gene activity in the allopolyploid Arabidopsis suecica. BMC Genomics 2017; 18:653. [PMID: 28830347 PMCID: PMC5567635 DOI: 10.1186/s12864-017-4067-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 08/16/2017] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Allopolyploids contain genomes composed of more than two complete sets of chromosomes that originate from at least two species. Allopolyploidy has been suggested as an important evolutionary mechanism that can lead to instant speciation. Arabidopsis suecica is a relatively recent allopolyploid species, suggesting that its natural accessions might be genetically very similar to each other. Nonetheless, subtle phenotypic differences have been described between different geographic accessions of A. suecica grown in a common garden. RESULTS To determine the degree of genomic similarity between different populations of A. suecica, we obtained transcriptomic sequence, quantified SNP variation within the gene space, and analyzed gene expression levels genome-wide from leaf material grown in controlled lab conditions. Despite their origin from the same progenitor species, the two accessions of A. suecica used in our study show genomic and transcriptomic variation. We report significant gene expression differences between the accessions, mostly in genes with stress-related functions. Among the differentially expressed genes, there are a surprising number of homoeologs coordinately regulated between sister accessions. CONCLUSIONS Many of these homoeologous genes and other differentially expressed genes affect transpiration and stomatal regulation, suggesting that they might be involved in the establishment of the phenotypic differences between the two accessions.
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Affiliation(s)
- Keisha D. Carlson
- Department of Biology, University of Puget Sound, 1500 N Warner St, CMB 1088, Tacoma, WA 98416 USA
| | | | - Aureliano Bombarely
- Boyce Thompson Institute, 533 Tower Road, Ithaca, NY 14853 USA
- Present Address: Virginia Tech, Department of Horticulture, 216 Latham Hall, Blacksburg, VA 24061 USA
| | - Rahul Pisupati
- Gregor Mendel Institute of Molecular Plant Biology, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | | | - Andreas Madlung
- Department of Biology, University of Puget Sound, 1500 N Warner St, CMB 1088, Tacoma, WA 98416 USA
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14
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Soltis DE, Visger CJ, Marchant DB, Soltis PS. Polyploidy: Pitfalls and paths to a paradigm. AMERICAN JOURNAL OF BOTANY 2016; 103:1146-66. [PMID: 27234228 DOI: 10.3732/ajb.1500501] [Citation(s) in RCA: 164] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 02/25/2016] [Indexed: 05/22/2023]
Abstract
Investigators have long searched for a polyploidy paradigm-rules or principles that might be common following polyploidization (whole-genome duplication, WGD). Here we attempt to integrate what is known across the more thoroughly investigated polyploid systems on topics ranging from genetics to ecology. We found that while certain rules may govern gene retention and loss, systems vary in the prevalence of gene silencing vs. homeolog loss, chromosomal change, the presence of a dominant genome (in allopolyploids), and the relative importance of hybridization vs. genome doubling per se. In some lineages, aspects of polyploidization are repeated across multiple origins, but in other species multiple origins behave more stochastically in terms of genetic and phenotypic change. Our investigation also reveals that the path to synthesis is hindered by numerous gaps in our knowledge of even the best-known systems. Particularly concerning is the absence of linkage between genotype and phenotype. Moreover, most recent studies have focused on the genetic and genomic attributes of polyploidy, but rarely is there an ecological or physiological context. To promote a path to a polyploidy paradigm (or paradigms), we propose a major community goal over the next 10-20 yr to fill the gaps in our knowledge of well-studied polyploids. Before a meaningful synthesis is possible, more complete data sets are needed for comparison-systems that include comparable genetic, genomic, chromosomal, proteomic, as well as morphological, physiological, and ecological data. Also needed are more natural evolutionary model systems, as most of what we know about polyploidy continues to come from a few crop and genetic models, systems that often lack the ecological context inherent in natural systems and necessary for understanding the drivers of biodiversity.
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Affiliation(s)
- Douglas E Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611 USA Department of Biology, University of Florida, Gainesville, Florida 32611 USA Genetics Institute, University of Florida, Gainesville, Florida 32608 USA
| | - Clayton J Visger
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611 USA Department of Biology, University of Florida, Gainesville, Florida 32611 USA
| | - D Blaine Marchant
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611 USA Department of Biology, University of Florida, Gainesville, Florida 32611 USA
| | - Pamela S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611 USA Genetics Institute, University of Florida, Gainesville, Florida 32608 USA
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15
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Gautam M, Dang Y, Ge X, Shao Y, Li Z. Genetic and Epigenetic Changes in Oilseed Rape (Brassica napus L.) Extracted from Intergeneric Allopolyploid and Additions with Orychophragmus. FRONTIERS IN PLANT SCIENCE 2016; 7:438. [PMID: 27148282 PMCID: PMC4828432 DOI: 10.3389/fpls.2016.00438] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 03/21/2016] [Indexed: 05/24/2023]
Abstract
Allopolyploidization with the merger of the genomes from different species has been shown to be associated with genetic and epigenetic changes. But the maintenance of such alterations related to one parental species after the genome is extracted from the allopolyploid remains to be detected. In this study, the genome of Brassica napus L. (2n = 38, genomes AACC) was extracted from its intergeneric allohexaploid (2n = 62, genomes AACCOO) with another crucifer Orychophragmus violaceus (2n = 24, genome OO), by backcrossing and development of alien addition lines. B. napus-type plants identified in the self-pollinated progenies of nine monosomic additions were analyzed by the methods of amplified fragment length polymorphism, sequence-specific amplified polymorphism, and methylation-sensitive amplified polymorphism. They showed modifications to certain extents in genomic components (loss and gain of DNA segments and transposons, introgression of alien DNA segments) and DNA methylation, compared with B. napus donor. The significant differences in the changes between the B. napus types extracted from these additions likely resulted from the different effects of individual alien chromosomes. Particularly, the additions which harbored the O. violaceus chromosome carrying dominant rRNA genes over those of B. napus tended to result in the development of plants which showed fewer changes, suggesting a role of the expression levels of alien rRNA genes in genomic stability. These results provided new cues for the genetic alterations in one parental genome that are maintained even after the genome becomes independent.
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Affiliation(s)
- Mayank Gautam
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Yanwei Dang
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Xianhong Ge
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Yujiao Shao
- College of Chemistry and Life Science, Hubei University of EducationWuhan, China
| | - Zaiyun Li
- National Key Laboratory of Crop Genetic Improvement, National Center of Oil Crop Improvement (Wuhan), College of Plant Science and Technology, Huazhong Agricultural UniversityWuhan, China
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16
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Abstract
Allopolyploidy involves hybridization and duplication of divergent parental genomes and provides new avenues for gene expression. The expression levels of duplicated genes in polyploids can show deviation from parental additivity (the arithmetic average of the parental expression levels). Nonadditive expression has been widely observed in diverse polyploids and comprises at least three possible scenarios: (a) The total gene expression level in a polyploid is similar to that of one of its parents (expression-level dominance); (b) total gene expression is lower or higher than in both parents (transgressive expression); and (c) the relative contribution of the parental copies (homeologs) to the total gene expression is unequal (homeolog expression bias). Several factors may result in expression nonadditivity in polyploids, including maternal-paternal influence, gene dosage balance, cis- and/or trans-regulatory networks, and epigenetic regulation. As our understanding of nonadditive gene expression in polyploids remains limited, a new generation of investigators should explore additional phenomena (i.e., alternative splicing) and use other high-throughput "omics" technologies to measure the impact of nonadditive expression on phenotype, proteome, and metabolome.
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Affiliation(s)
- Mi-Jeong Yoo
- Department of Biology, University of Florida, Gainesville, Florida 32611-8525; , ,
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17
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Gene Expression Differences between High-Growth Populus Allotriploids and Their Diploid Parents. FORESTS 2015. [DOI: 10.3390/f6030839] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Saminathan T, Nimmakayala P, Manohar S, Malkaram S, Almeida A, Cantrell R, Tomason Y, Abburi L, Rahman MA, Vajja VG, Khachane A, Kumar B, Rajasimha HK, Levi A, Wehner T, Reddy UK. Differential gene expression and alternative splicing between diploid and tetraploid watermelon. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:1369-85. [PMID: 25520388 PMCID: PMC4438448 DOI: 10.1093/jxb/eru486] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The exploitation of synthetic polyploids for producing seedless fruits is well known in watermelon. Tetraploid progenitors of triploid watermelon plants, compared with their diploid counterparts, exhibit wide phenotypic differences. Although many factors modulate alternative splicing (AS) in plants, the effects of autopolyploidization on AS are still unknown. In this study, we used tissues of leaf, stem, and fruit of diploid and tetraploid sweet watermelon to understand changes in gene expression and the occurrence of AS. RNA-sequencing analysis was performed along with reverse transcription quantitative PCR and rapid amplification of cDNA ends (RACE)-PCR to demonstrate changes in expression and splicing. All vegetative tissues except fruit showed an increased level of AS in the tetraploid watermelon throughout the growth period. The ploidy levels of diploids and the tetraploid were confirmed using a ploidy analyser. We identified 5362 and 1288 genes that were up- and downregulated, respectively, in tetraploid as compared with diploid plants. We further confirmed that 22 genes underwent AS events across tissues, indicating possibilities of generating different protein isoforms with altered functions of important transcription factors and transporters. Arginine biosynthesis, chlorophyllide synthesis, GDP mannose biosynthesis, trehalose biosynthesis, and starch and sucrose degradation pathways were upregulated in autotetraploids. Phloem protein 2, chloroplastic PGR5-like protein, zinc-finger protein, fructokinase-like 2, MYB transcription factor, and nodulin MtN21 showed AS in fruit tissues. These results should help in developing high-quality seedless watermelon and provide additional transcriptomic information related to other cucurbits.
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Affiliation(s)
- Thangasamy Saminathan
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Padma Nimmakayala
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Sumanth Manohar
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Sridhar Malkaram
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Aldo Almeida
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Robert Cantrell
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Yan Tomason
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Lavanya Abburi
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Mohammad A Rahman
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Venkata G Vajja
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
| | - Amit Khachane
- Genome International Corporation, 8000 Excelsior Drive, Suite 202, Madison, WI 53717, USA
| | - Brajendra Kumar
- Genome International Corporation, 8000 Excelsior Drive, Suite 202, Madison, WI 53717, USA
| | - Harsha K Rajasimha
- Genome International Corporation, 8000 Excelsior Drive, Suite 202, Madison, WI 53717, USA
| | - Amnon Levi
- US Vegetable Laboratory, USDA-ARS, 2875 Savannah Highway, Charleston, SC 29414, USA
| | - Todd Wehner
- Department of Horticultural Science, North Carolina State University, Raleigh, NC 27695-7609, USA
| | - Umesh K Reddy
- Department of Biology, Gus R. Douglass Institute, West Virginia State University, Institute, WV 25112-1000, USA
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19
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Buggs RJA, Wendel JF, Doyle JJ, Soltis DE, Soltis PS, Coate JE. The legacy of diploid progenitors in allopolyploid gene expression patterns. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0354. [PMID: 24958927 DOI: 10.1098/rstb.2013.0354] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Allopolyploidization (hybridization and whole-genome duplication) is a common phenomenon in plant evolution with immediate saltational effects on genome structure and gene expression. New technologies have allowed rapid progress over the past decade in our understanding of the consequences of allopolyploidy. A major question, raised by early pioneer of this field Leslie Gottlieb, concerned the extent to which gene expression differences among duplicate genes present in an allopolyploid are a legacy of expression differences that were already present in the progenitor diploid species. Addressing this question necessitates phylogenetically well-understood natural study systems, appropriate technology, availability of genomic resources and a suitable analytical framework, including a sufficiently detailed and generally accepted terminology. Here, we review these requirements and illustrate their application to a natural study system that Gottlieb worked on and recommended for this purpose: recent allopolyploids of Tragopogon (Asteraceae). We reanalyse recent data from this system within the conceptual framework of parental legacies on duplicate gene expression in allopolyploids. On a broader level, we highlight the intellectual connection between Gottlieb's phrasing of this issue and the more contemporary framework of cis- versus trans-regulation of duplicate gene expression in allopolyploid plants.
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Affiliation(s)
- Richard J A Buggs
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, UK
| | - Jonathan F Wendel
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames IA 50011, USA
| | - Jeffrey J Doyle
- L. H. Bailey Hortorium, Department of Plant Biology, Cornell University, Ithaca, NY 14853, USA
| | - Douglas E Soltis
- Department of Biology, University of Florida, Gainesville, FL 32611, USA Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | - Pamela S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | - Jeremy E Coate
- Department of Biology, Reed College, Portland, OR 97202, USA
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20
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Jiang J, Wang Y, Zhu B, Fang T, Fang Y, Wang Y. Digital gene expression analysis of gene expression differences within Brassica diploids and allopolyploids. BMC PLANT BIOLOGY 2015; 15:22. [PMID: 25623840 PMCID: PMC4312607 DOI: 10.1186/s12870-015-0417-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 01/08/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND Brassica includes many successfully cultivated crop species of polyploid origin, either by ancestral genome triplication or by hybridization between two diploid progenitors, displaying complex repetitive sequences and transposons. The U's triangle, which consists of three diploids and three amphidiploids, is optimal for the analysis of complicated genomes after polyploidization. Next-generation sequencing enables the transcriptome profiling of polyploids on a global scale. RESULTS We examined the gene expression patterns of three diploids (Brassica rapa, B. nigra, and B. oleracea) and three amphidiploids (B. napus, B. juncea, and B. carinata) via digital gene expression analysis. In total, the libraries generated between 5.7 and 6.1 million raw reads, and the clean tags of each library were mapped to 18547-21995 genes of B. rapa genome. The unambiguous tag-mapped genes in the libraries were compared. Moreover, the majority of differentially expressed genes (DEGs) were explored among diploids as well as between diploids and amphidiploids. Gene ontological analysis was performed to functionally categorize these DEGs into different classes. The Kyoto Encyclopedia of Genes and Genomes analysis was performed to assign these DEGs into approximately 120 pathways, among which the metabolic pathway, biosynthesis of secondary metabolites, and peroxisomal pathway were enriched. The non-additive genes in Brassica amphidiploids were analyzed, and the results indicated that orthologous genes in polyploids are frequently expressed in a non-additive pattern. Methyltransferase genes showed differential expression pattern in Brassica species. CONCLUSION Our results provided an understanding of the transcriptome complexity of natural Brassica species. The gene expression changes in diploids and allopolyploids may help elucidate the morphological and physiological differences among Brassica species.
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Affiliation(s)
- Jinjin Jiang
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China.
| | - Yue Wang
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China.
| | - Bao Zhu
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China.
| | - Tingting Fang
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China.
| | - Yujie Fang
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China.
| | - Youping Wang
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou, 225009, China.
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Nayidu NK, Tan Y, Taheri A, Li X, Bjorndahl TC, Nowak J, Wishart DS, Hegedus D, Gruber MY. Brassica villosa, a system for studying non-glandular trichomes and genes in the Brassicas. PLANT MOLECULAR BIOLOGY 2014; 85:519-39. [PMID: 24831512 DOI: 10.1007/s11103-014-0201-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 05/11/2014] [Indexed: 05/18/2023]
Abstract
Brassica villosa is a wild Brassica C genome species with very dense trichome coverage and strong resistance to many insect pests of Brassica oilseeds and vegetables. Transcriptome analysis of hairy B. villosa leaves indicated higher expression of several important trichome initiation genes compared with glabrous B. napus leaves and consistent with the Arabidopsis model of trichome development. However, transcripts of the TRY inhibitory gene in hairy B. villosa were surprisingly high relative to B. napus and relative transcript levels of SAD2, EGL3, and several XIX genes were low, suggesting potential ancillary or less important trichome-related roles for these genes in Brassica species compared with Arabidopsis. Several antioxidant, calcium, non-calcium metal and secondary metabolite genes also showed differential expression between these two species. These coincided with accumulation of two alkaloid-like compounds, high levels of calcium, and other metals in B. villosa trichomes that are correlated with the known tolerance of B. villosa to high salt and the calcium-rich natural habitat of this wild species. This first time report on the isolation of large amounts of pure B. villosa trichomes, on trichome content, and on relative gene expression differences in an exceptionally hairy Brassica species compared with a glabrous species opens doors for the scientific community to understand trichome gene function in the Brassicas and highlights the potential of B. villosa as a trichome research platform.
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Affiliation(s)
- Naghabushana K Nayidu
- Saskatoon Research Centre, Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK, S7N0X2, Canada,
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23
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Li Q, Mei J, Zhang Y, Li J, Ge X, Li Z, Qian W. A large-scale introgression of genomic components of Brassica rapa into B. napus by the bridge of hexaploid derived from hybridization between B. napus and B. oleracea. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2013; 126:2073-2080. [PMID: 23699961 DOI: 10.1007/s00122-013-2119-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Accepted: 05/08/2013] [Indexed: 06/02/2023]
Abstract
Brassica rapa (AA) has been used to widen the genetic basis of B. napus (AACC), which is a new but important oilseed crop worldwide. In the present study, we have proposed a strategy to develop new type B. napus carrying genomic components of B. rapa by crossing B. rapa with hexaploid (AACCCC) derived from B. napus and B. oleracea (CC). The hexaploid exhibited large flowers and high frequency of normal chromosome segregation, resulting in good seed set (average of 4.48 and 12.53 seeds per pod by self and open pollination, respectively) and high pollen fertility (average of 87.05 %). It was easy to develop new type B. napus by crossing the hexaploid with 142 lines of B. rapa from three ecotype groups, with the average crossability of 9.24 seeds per pod. The genetic variation of new type B. napus was diverse from that of current B. napus, especially in the A subgenome, revealed by genome-specific simple sequence repeat markers. Our data suggest that the strategy proposed here is a large-scale and highly efficient method to introgress genomic components of B. rapa into B. napus.
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Affiliation(s)
- Qinfei Li
- College of Agronomy and Biotechnology, Southwest University, Chongqing, China
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Zhao Q, Zou J, Meng J, Mei S, Wang J. Tracing the transcriptomic changes in synthetic Trigenomic allohexaploids of Brassica using an RNA-Seq approach. PLoS One 2013; 8:e68883. [PMID: 23874799 PMCID: PMC3708896 DOI: 10.1371/journal.pone.0068883] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 06/02/2013] [Indexed: 01/07/2023] Open
Abstract
Polyploidization has played an important role in plant evolution and speciation, and newly formed allopolyploids have experienced rapid transcriptomic changes. Here, we compared the transcriptomic differences between a synthetic Brassica allohexaploid and its parents using a high-throughput RNA-Seq method. A total of 35,644,409 sequence reads were generated, and 32,642 genes were aligned from the data. Totals of 29,260, 29,060, and 29,697 genes were identified in Brassicarapa, Brassicacarinata, and Brassica allohexaploid, respectively. We compared 7,397 differentially expressed genes (DEGs) between Brassica hexaploid and its parents, as well as 2,545 nonadditive genes of Brassica hexaploid. We hypothesized that the higher ploidy level as well as secondary polyploidy might have influenced these changes. The majority of the 3,184 DEGs between Brassica hexaploid and its paternal parent, B. rapa, were involved in the biosynthesis of secondary metabolites, plant–pathogen interactions, photosynthesis, and circadian rhythm. Among the 2,233 DEGs between Brassica hexaploid and its maternal parent, B. carinata, several played roles in plant–pathogen interactions, plant hormone signal transduction, ribosomes, limonene and pinene degradation, photosynthesis, and biosynthesis of secondary metabolites. There were more significant differences in gene expression between the allohexaploid and its paternal parent than between it and its maternal parent, possibly partly because of cytoplasmic and maternal effects. Specific functional categories were enriched among the 2,545 nonadditive genes of Brassica hexaploid compared with the additive genes; the categories included response to stimulus, immune system process, cellular process, metabolic process, rhythmic process, and pigmentation. Many transcription factor genes, methyltransferases, and methylation genes showed differential expression between Brassica hexaploid and its parents. Our results demonstrate that the Brassica allohexaploid can generate extensive transcriptomic diversity compared with its parents. These changes may contribute to the normal growth and reproduction of allohexaploids.
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Affiliation(s)
- Qin Zhao
- National Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jun Zou
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Jinling Meng
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Shiyong Mei
- Hubei Academy of Agricultural Science, Wuhan, China
| | - Jianbo Wang
- National Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
- * E-mail:
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Sarilar V, Palacios PM, Rousselet A, Ridel C, Falque M, Eber F, Chèvre AM, Joets J, Brabant P, Alix K. Allopolyploidy has a moderate impact on restructuring at three contrasting transposable element insertion sites in resynthesized Brassica napus allotetraploids. THE NEW PHYTOLOGIST 2013; 198:593-604. [PMID: 23384044 DOI: 10.1111/nph.12156] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 12/19/2012] [Indexed: 05/02/2023]
Abstract
The role played by whole-genome duplication (WGD) in evolution and adaptation is particularly well illustrated in allopolyploids, where WGD is concomitant with interspecific hybridization. This 'Genome Shock', usually accompanied by structural and functional modifications, has been associated with the activation of transposable elements (TEs). However, the impact of allopolyploidy on TEs has been studied in only a few polyploid species, and not in Brassica, which has been marked by recurrent polyploidy events. Here, we developed sequence-specific amplification polymorphism (SSAP) markers for three contrasting TEs, and compared profiles between resynthesized Brassica napus allotetraploids and their diploid Brassica progenitors. To evaluate restructuring at TE insertion sites, we scored changes in SSAP profiles and analysed a large set of differentially amplified SSAP bands. No massive structural changes associated with the three TEs surveyed were detected. However, several transposition events, specific to the youngest TE originating from the B. oleracea genome, were identified. Our study supports the hypothesis that TE responses to allopolyploidy are highly specific. The changes observed in SSAP profiles lead us to hypothesize that they may partly result from changes in DNA methylation, questioning the role of epigenetics during the formation of a new allopolyploid genome.
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Affiliation(s)
- Véronique Sarilar
- AgroParisTech, 16 rue Claude Bernard, F-75231 Paris Cedex 05, France
- CNRS, UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
| | - Paulina Martinez Palacios
- Université Paris-Sud, UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
| | - Agnès Rousselet
- INRA, UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
| | - Céline Ridel
- INRA, UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
| | - Matthieu Falque
- INRA, UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
| | - Frédérique Eber
- INRA, UMR 1349 IGEPP, BP 35327, F-35653 Le Rheu Cedex, France
| | | | - Johann Joets
- INRA, UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
| | - Philippe Brabant
- AgroParisTech, 16 rue Claude Bernard, F-75231 Paris Cedex 05, France
- UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
| | - Karine Alix
- AgroParisTech, 16 rue Claude Bernard, F-75231 Paris Cedex 05, France
- UMR 0320/8120 Génétique Végétale, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
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Chelaifa H, Chagué V, Chalabi S, Mestiri I, Arnaud D, Deffains D, Lu Y, Belcram H, Huteau V, Chiquet J, Coriton O, Just J, Jahier J, Chalhoub B. Prevalence of gene expression additivity in genetically stable wheat allohexaploids. THE NEW PHYTOLOGIST 2013; 197:730-736. [PMID: 23278496 DOI: 10.1111/nph.12108] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 11/20/2012] [Indexed: 05/18/2023]
Abstract
The reprogramming of gene expression appears as the major trend in synthetic and natural allopolyploids where expression of an important proportion of genes was shown to deviate from that of the parents or the average of the parents. In this study, we analyzed gene expression changes in previously reported, highly stable synthetic wheat allohexaploids that combine the D genome of Aegilops tauschii and the AB genome extracted from the natural hexaploid wheat Triticum aestivum. A comprehensive genome-wide analysis of transcriptional changes using the Affymetrix GeneChip Wheat Genome Array was conducted. Prevalence of gene expression additivity was observed where expression does not deviate from the average of the parents for 99.3% of 34,820 expressed transcripts. Moreover, nearly similar expression was observed (for 99.5% of genes) when comparing these synthetic and natural wheat allohexaploids. Such near-complete additivity has never been reported for other allopolyploids and, more interestingly, for other synthetic wheat allohexaploids that differ from the ones studied here by having the natural tetraploid Triticum turgidum as the AB genome progenitor. Our study gave insights into the dynamics of additive gene expression in the highly stable wheat allohexaploids.
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Affiliation(s)
- Houda Chelaifa
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Véronique Chagué
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Smahane Chalabi
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Imen Mestiri
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Dominique Arnaud
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Denise Deffains
- Unité Mixte de Recherches INRA, Agrocampus Rennes - Université Rennes 1, Institut de Génétique, Environnement et Protection des Plantes (IGEPP), 35653, Le Rheu, France
| | - Yunhai Lu
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Harry Belcram
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Virginie Huteau
- Unité Mixte de Recherches INRA, Agrocampus Rennes - Université Rennes 1, Institut de Génétique, Environnement et Protection des Plantes (IGEPP), 35653, Le Rheu, France
| | - Julien Chiquet
- Laboratoire Statistique et Génome, Université d'Évry Val d'Essonne, UMR CNRS 8071 - USC INRA, Evry, France
| | - Olivier Coriton
- Unité Mixte de Recherches INRA, Agrocampus Rennes - Université Rennes 1, Institut de Génétique, Environnement et Protection des Plantes (IGEPP), 35653, Le Rheu, France
| | - Jérémy Just
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
| | - Joseph Jahier
- Unité Mixte de Recherches INRA, Agrocampus Rennes - Université Rennes 1, Institut de Génétique, Environnement et Protection des Plantes (IGEPP), 35653, Le Rheu, France
| | - Boulos Chalhoub
- Unité de Recherche en Génomique Végétale URGV (INRA- CNRS - UEVE), Organization and Evolution of Plant Genomes, 91057, Evry Cedex, France
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Jiang J, Shao Y, Du K, Ran L, Fang X, Wang Y. Use of digital gene expression to discriminate gene expression differences in early generations of resynthesized Brassica napus and its diploid progenitors. BMC Genomics 2013; 14:72. [PMID: 23369045 PMCID: PMC3608150 DOI: 10.1186/1471-2164-14-72] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/29/2013] [Indexed: 12/04/2022] Open
Abstract
Background Polyploidy is an important evolutionary mechanism in flowering plants that often induces immediate extensive changes in gene expression through genomic merging and doubling. Brassica napus L. is one of the most economically important polyploid oil crops and has been broadly studied as an example of polyploid crop. RNA-seq is a recently developed technique for transcriptome study, which could be in choice for profiling gene expression pattern in polyploids. Results We examined the global gene expression patterns of the first four generations of resynthesized B. napus (F1–F4), its diploid progenitors B. rapa and B. oleracea, and natural B. napus using digital gene expression analysis. Almost 42 million clean tags were generated using Illumina technology to produce the expression data for 25959 genes, which account for 63% of the annotated B. rapa genome. More than 56% of the genes were transcribed from both strands, which indicate the importance of RNA-mediated gene regulation in polyploidization. Tag mapping of the B. rapa genome generated 19023, 18547, 24383, 20659, 18881, 20692, and 19955 annotated genes for the B. rapa, B. oleracea, F1–F4 of synthesized B. napus, and natural B. napus libraries, respectively. The unambiguous tag-mapped genes in the libraries were functionally categorized via gene ontological analysis. Thousands of differentially expressed genes (DEGs) were identified and revealed the substantial changes in F1–F4. Among the 20 most DEGs are DNA binding/transcription factor, cyclin-dependent protein kinase, epoxycarotenoid dioxygenase, and glycine-rich protein. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the DEGs suggested approximately 120 biological pathways. Conclusions The systematic deep sequencing analysis provided a comprehensive understanding of the transcriptome complexity of early generations of synthesized B. napus. This information broadens our understanding of the mechanisms of B. napus polyploidization and contributes to molecular and genetic research by enriching the Brassica database.
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Affiliation(s)
- Jinjin Jiang
- Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou 225009, China
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Madlung A. Polyploidy and its effect on evolutionary success: old questions revisited with new tools. Heredity (Edinb) 2013; 110:99-104. [PMID: 23149459 PMCID: PMC3554449 DOI: 10.1038/hdy.2012.79] [Citation(s) in RCA: 238] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 10/01/2012] [Accepted: 10/02/2012] [Indexed: 11/09/2022] Open
Abstract
Polyploidy, the condition of possessing more than two complete genomes in a cell, has intrigued biologists for almost a century. Polyploidy is found in many plants and some animal species and today we know that polyploidy has had a role in the evolution of all angiosperms. Despite its widespread occurrence, the direct effect of polyploidy on evolutionary success of a species is still largely unknown. Over the years many attractive hypotheses have been proposed in an attempt to assign functionality to the increased content of a duplicated genome. Among these hypotheses are the proposal that genome doubling confers distinct advantages to a polyploid and that these advantages allow polyploids to thrive in environments that pose challenges to the polyploid's diploid progenitors. This article revisits these long-standing questions and explores how the integration of recent genomic developments with ecological, physiological and evolutionary perspectives has contributed to addressing unresolved problems about the role of polyploidy. Although unsatisfactory, the current conclusion has to be that despite significant progress, there still isn't enough information to unequivocally answer many unresolved questions about cause and effect of polyploidy on evolutionary success of a species. There is, however, reason to believe that the increasingly integrative approaches discussed here should allow us in the future to make more direct connections between the effects of polyploidy on the genome and the responses this condition elicits from the organism living in its natural environment.
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Affiliation(s)
- A Madlung
- Department of Biology, University of Puget Sound, Tacoma, WA 98416, USA.
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Akhunov ED, Sehgal S, Liang H, Wang S, Akhunova AR, Kaur G, Li W, Forrest KL, See D, Simková H, Ma Y, Hayden MJ, Luo M, Faris JD, Dolezel J, Gill BS. Comparative analysis of syntenic genes in grass genomes reveals accelerated rates of gene structure and coding sequence evolution in polyploid wheat. PLANT PHYSIOLOGY 2013; 161:252-65. [PMID: 23124323 PMCID: PMC3532256 DOI: 10.1104/pp.112.205161] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Cycles of whole-genome duplication (WGD) and diploidization are hallmarks of eukaryotic genome evolution and speciation. Polyploid wheat (Triticum aestivum) has had a massive increase in genome size largely due to recent WGDs. How these processes may impact the dynamics of gene evolution was studied by comparing the patterns of gene structure changes, alternative splicing (AS), and codon substitution rates among wheat and model grass genomes. In orthologous gene sets, significantly more acquired and lost exonic sequences were detected in wheat than in model grasses. In wheat, 35% of these gene structure rearrangements resulted in frame-shift mutations and premature termination codons. An increased codon mutation rate in the wheat lineage compared with Brachypodium distachyon was found for 17% of orthologs. The discovery of premature termination codons in 38% of expressed genes was consistent with ongoing pseudogenization of the wheat genome. The rates of AS within the individual wheat subgenomes (21%-25%) were similar to diploid plants. However, we uncovered a high level of AS pattern divergence between the duplicated homeologous copies of genes. Our results are consistent with the accelerated accumulation of AS isoforms, nonsynonymous mutations, and gene structure rearrangements in the wheat lineage, likely due to genetic redundancy created by WGDs. Whereas these processes mostly contribute to the degeneration of a duplicated genome and its diploidization, they have the potential to facilitate the origin of new functional variations, which, upon selection in the evolutionary lineage, may play an important role in the origin of novel traits.
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Affiliation(s)
- Eduard D Akhunov
- Department of Plant Pathology , Kansas State University, Manhattan, Kansas 66506, USA.
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Yoo MJ, Szadkowski E, Wendel JF. Homoeolog expression bias and expression level dominance in allopolyploid cotton. Heredity (Edinb) 2012; 110:171-80. [PMID: 23169565 DOI: 10.1038/hdy.2012.94] [Citation(s) in RCA: 250] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Allopolyploidy is an evolutionary and mechanistically intriguing process, in that it entails the reconciliation of two or more sets of diverged genomes and regulatory interactions. In this study, we explored gene expression patterns in interspecific hybrid F(1), and synthetic and natural allopolyploid cotton using RNA-Seq reads from leaf transcriptomes. We determined how the extent and direction of expression level dominance (total level of expression for both homoeologs) and homoeolog expression bias (relative contribution of homoeologs to the transcriptome) changed from hybridization through evolution at the polyploid level and following cotton domestication. Genome-wide expression level dominance was biased toward the A-genome in the diploid hybrid and natural allopolyploids, whereas the direction was reversed in the synthetic allopolyploid. This biased expression level dominance was mainly caused by up- or downregulation of the homoeolog from the 'non-dominant' parent. Extensive alterations in homoeolog expression bias and expression level dominance accompany the initial merger of two diverged diploid genomes, suggesting a combination of regulatory (cis or trans) and epigenetic interactions that may arise and propagate through the transcriptome network. The extent of homoeolog expression bias and expression level dominance increases over time, from genome merger through evolution at the polyploid level. Higher rates of transgressive and novel gene expression patterns as well as homoeolog silencing were observed in natural allopolyploids than in F(1) hybrid and synthetic allopolyploid cottons. These observations suggest that natural selection reconciles the regulatory mismatches caused by initial genomic merger, while new gene expression conditions are generated for evaluation by selection.
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Affiliation(s)
- M-J Yoo
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA 50011, USA
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Osabe K, Kawanabe T, Sasaki T, Ishikawa R, Okazaki K, Dennis ES, Kazama T, Fujimoto R. Multiple mechanisms and challenges for the application of allopolyploidy in plants. Int J Mol Sci 2012; 13:8696-8721. [PMID: 22942729 PMCID: PMC3430260 DOI: 10.3390/ijms13078696] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 07/04/2012] [Accepted: 07/04/2012] [Indexed: 11/16/2022] Open
Abstract
An allopolyploid is an individual having two or more complete sets of chromosomes derived from different species. Generation of allopolyploids might be rare because of the need to overcome limitations such as co-existing populations of parental lines, overcoming hybrid incompatibility, gametic non-reduction, and the requirement for chromosome doubling. However, allopolyploids are widely observed among plant species, so allopolyploids have succeeded in overcoming these limitations and may have a selective advantage. As techniques for making allopolyploids are developed, we can compare transcription, genome organization, and epigenetic modifications between synthesized allopolyploids and their direct parental lines or between several generations of allopolyploids. It has been suggested that divergence of transcription caused either genetically or epigenetically, which can contribute to plant phenotype, is important for the adaptation of allopolyploids.
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Affiliation(s)
- Kenji Osabe
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Plant Industry, Canberra, ACT 2601, Australia; E-Mails: (K.O.); (E.S.D.)
| | - Takahiro Kawanabe
- Watanabe Seed Co., Ltd, Machiyashiki, Misato-cho, Miyagi 987-8607, Japan; E-Mail:
| | - Taku Sasaki
- Watanabe Seed Co., Ltd, Machiyashiki, Misato-cho, Miyagi 987-8607, Japan; E-Mail:
| | - Ryo Ishikawa
- Laboratory of Plant Breeding, Graduate School of Agricultural Science, Kobe University, Nada, Kobe 657-8510, Japan; E-Mail:
- Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Colney, Norwich, NR4 7UH, UK; E-Mail:
| | - Keiichi Okazaki
- Graduate School of Science and Technology, Niigata University, Ikarashi-ninocho, Niigata 950-2181, Japan; E-Mail:
| | - Elizabeth S. Dennis
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Plant Industry, Canberra, ACT 2601, Australia; E-Mails: (K.O.); (E.S.D.)
| | - Tomohiko Kazama
- Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai 981-8555, Japan; E-Mail:
| | - Ryo Fujimoto
- Graduate School of Science and Technology, Niigata University, Ikarashi-ninocho, Niigata 950-2181, Japan; E-Mail:
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Higgins J, Magusin A, Trick M, Fraser F, Bancroft I. Use of mRNA-seq to discriminate contributions to the transcriptome from the constituent genomes of the polyploid crop species Brassica napus. BMC Genomics 2012; 13:247. [PMID: 22703051 PMCID: PMC3428664 DOI: 10.1186/1471-2164-13-247] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 05/29/2012] [Indexed: 11/22/2022] Open
Abstract
Background Polyploidy often results in considerable changes in gene expression, both immediately and over evolutionary time. New phenotypes often arise with polyploid formation and may contribute to the fitness of polyploids in nature or their selection for use in agriculture. Oilseed rape (Brassica napus) is widely used to study the process of polyploidy both in artificially resynthesised and natural forms. mRNA-Seq, a recently developed approach to transcriptome profiling using deep-sequencing technologies is an alternative to microarrays for the study of gene expression in a polyploid. Results Illumina mRNA-Seq is comparable to microarray analysis for transcript quantification but has increased sensitivity and, very importantly, the potential to distinguish between homoeologous genes in polyploids. Using a novel curing process, we adapted a reference sequence that was a consensus derived from ESTs from both Brassica A and C genomes to one containing separate A and C genome versions for each of the 94,558 original unigenes. We aligned reads from B. napus to this cured reference, finding 38% more reads mapping from resynthesised lines and 28% more reads mapping from natural lines. Where the A and C versions differed at single nucleotide positions, termed inter-homoeologue polymorphisms (IHPs), we were able to apportion expression in the polyploid between the A and C genome homoeologues. 43,761 unigenes contained at least one IHP, with a mean frequency of 10.5 per kb unigene sequence. 6,350 of the unigenes with IHPs were differentially expressed between homoeologous gene pairs in resynthesised B. napus. 3,212 unigenes showed a similar pattern of differential expression across a range of natural B. napus crop varieties and, of these, 995 were in common with resynthesised B. napus. Functional classification showed over-representation in gene ontology categories not associated with dosage-sensitivity. Conclusion mRNA-Seq is the method of choice for measuring transcript abundance in polyploids due to its ability to measure the contributions of homoeologues to gene expression. The identification of large numbers of differentially expressed genes in both a newly resynthesised polyploid and natural B. napus confirms that there are both immediate and long-term alterations in the expression of homoeologous gene pairs following polyploidy.
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Affiliation(s)
- Janet Higgins
- John Innes Centre, Norwich Research Park, Norwich, UK
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Grimanelli D. Epigenetic regulation of reproductive development and the emergence of apomixis in angiosperms. CURRENT OPINION IN PLANT BIOLOGY 2012; 15:57-62. [PMID: 22037465 DOI: 10.1016/j.pbi.2011.10.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 10/02/2011] [Accepted: 10/03/2011] [Indexed: 05/03/2023]
Abstract
Apomictic plants reproduce asexually through seeds by avoiding both meiosis and fertilization. While apomixis is genetically controlled, individual loci contributing to its expression have yet to be identified. Here, we review recent results indicating that RNA-dependent DNA methylation pathways acting during female reproduction are essential for proper reproductive development in plants, and may represent key regulators of the differentiation between apomictic and sexual reproduction.
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Affiliation(s)
- Daniel Grimanelli
- Institut de Recherche pour Développement, UMR 232, URL5300, Université de Montpellier II, 34394 Montpellier, France.
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Fujimoto R, Taylor JM, Sasaki T, Kawanabe T, Dennis ES. Genome wide gene expression in artificially synthesized amphidiploids of Arabidopsis. PLANT MOLECULAR BIOLOGY 2011; 77:419-31. [PMID: 21882042 DOI: 10.1007/s11103-011-9820-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 08/22/2011] [Indexed: 05/12/2023]
Abstract
The merging of two different genomes occurs during the formation of amphidiploids, and the merged regulatory networks have the potential to generate a new gene expression pattern. We examined the genome-wide gene expression of two newly synthesized amphidiploids between Arabidopsis thaliana and the related species Arabidopsis lyrata subsp. lyrata and Arabidopsis halleri subsp. gemmifera. 1,137 (4.7%) and 1,316 (5.4%) of probesets showed differential gene expression in A. thaliana-A. halleri and A. thaliana-A. lyrata hybrids respectively, compared to the mid parent value and of these, 489 were in common. Genes that differed in expression between the parental lines tended to have an expression level in both hybrids differing from the mid parent value. In contrast to protein coding genes, there is little differential expression of transposons. Genes in the categories of chloroplast-targeted and response to stress were overrepresented in the non-additively expressed genes in both amphidiploids. As these genes have the potential to contribute directly to the plant phenotype, we suggest that rapid changes of gene expression in amphidiploids might be important for producing greater biomass.
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Affiliation(s)
- Ryo Fujimoto
- CSIRO Plant Industry, Canberra, ACT 2601, Australia.
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Ng DWK, Zhang C, Miller M, Shen Z, Briggs SP, Chen ZJ. Proteomic divergence in Arabidopsis autopolyploids and allopolyploids and their progenitors. Heredity (Edinb) 2011; 108:419-30. [PMID: 22009271 DOI: 10.1038/hdy.2011.92] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Autopolyploidy and allopolyploidy are common in many plants and some animals. Rapid changes in genomic composition and gene expression have been observed in both autopolyploids and allopolyploids, but the effects of polyploidy on proteomic divergence are poorly understood. Here, we report quantitative analysis of protein changes in leaves of Arabidopsis autopolyploids and allotetraploids and their progenitors using isobaric tags for relative and absolute quantitation (iTRAQ) coupled with mass spectrometry. In more than 1000 proteins analyzed, the levels of protein divergence were relatively high (~18%) between Arabidopsis thaliana and Arabidopsis arenosa, relatively low (~6.8%) between an A. thaliana diploid and autotetraploid and intermediate (~8.3 and 8.2%) in F(1)- and F(8)-resynthesized allotetraploids relative to mid-parent values, respectively. This pattern of proteomic divergence was consistent with the previously reported gene expression data. In particular, many non-additively accumulated proteins (61-62%) in the F(1) and F(8) allotetraploids were also differentially expressed between the parents. The differentially accumulated proteins in functional categories of abiotic and biotic stresses were overrepresented between an A. thaliana autotetraploid and diploid and between two Arabidopsis species, but not significantly different between allotetraploids and their progenitors. Although the trend of changes is similar, the percentage of differentially accumulated proteins that matched previously reported differentially expressed genes was relatively low. Western blot analysis confirmed several selected proteins with isoforms the cumulative levels of which were differentially expressed. These data suggest high protein divergence between species and rapid changes in post-transcriptional regulation and translational modifications of proteins during polyploidization.
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Affiliation(s)
- D W-K Ng
- Section of Molecular Cell and Developmental Biology, Center for Computational Biology and Bioinformatics, and Institute for Cellular and Molecular Biology, The University of Texas at Austin, TX, USA
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Li A, Fang MD, Song WQ, Chen CB, Qi LW, Wang CG. Gene expression profiles of two intraspecific Larix lines and their reciprocal hybrids. Mol Biol Rep 2011; 39:3773-84. [PMID: 21750915 DOI: 10.1007/s11033-011-1154-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2011] [Accepted: 06/30/2011] [Indexed: 12/17/2022]
Abstract
Heterosis has been widely explored in Larix breeding for more than a century, but the molecular mechanisms underlying this phenomenon remain elusive. In the present study, the genome-wide transcript profiles from two Larix genotypes and their reciprocal hybrids were analyzed using Arabidopsis 70-mer oligonucleotide microarrays. Despite sharing the same two parental lines, one of the hybrids showed obvious heterosis, while the other did not. In total, 1,171 genes were differentially expressed between the heterotic hybrid and its parents, of which 133 genes were nonadditive expression. The number of differentially expressed genes between the non-heterotic hybrid and the parents was 939, but only 54 of these genes were nonadditive expression. Further, gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses indicated that most of these differentially expressed genes in the heterotic hybrid were associated with several important biological functions such as physiological processes, responses to stimulus, and starch and sucrose metabolism. The reliability of the microarray data was further validated by the Real-time quantitative RT-PCR. A high Pearson linear correlation coefficient value was detected (r = 0.759, P < 0.01). In conclusion, the gene expression profile in the Larix heterotic hybrid was significantly different from that obtained from the non-heterotic hybrid, and more nonadditive differentially expressed genes were detected in the heterotic hybrid, implying that nonadditive effects may be closely associated with the formation of heterosis in the intraspecific Larix hybridization.
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Affiliation(s)
- Ai Li
- College of Life Sciences, Nankai University, Tianjin, 300071, People's Republic of China
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Xu SX, Cai XD, Tan B, Li DL, Guo WW. Effect of ploidy increase on transgene expression: example from Citrus diploid cybrid and allotetraploid somatic hybrid expressing the EGFP gene. PROTOPLASMA 2011; 248:531-540. [PMID: 20734092 DOI: 10.1007/s00709-010-0200-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Accepted: 08/11/2010] [Indexed: 05/29/2023]
Abstract
Polyploidization is an important speciation mechanism for all eukaryotes, and it has profound impacts on biodiversity dynamics and ecosystem functioning. Green fluorescent protein (GFP) has been used as an effective marker to visually screen somatic hybrids at an early stage in protoplast fusion. We have previously reported that the intensity of GFP fluorescence of regenerated embryoids was also an early indicator of ploidy level. However, little is known concerning the effects of ploidy increase on the GFP expression in citrus somatic hybrids at the plant level. Herein, allotetraploid and diploid cybrid plants with enhanced GFP (EGFP) expression were regenerated from the fusion of embryogenic callus protoplasts from 'Murcott' tangor (Citrus reticulata Blanco × Citrus sinensis (L.) Osbeck) and mesophyll protoplasts from transgenic 'Valencia' orange (C. sinensis (L.) Osbeck) expressing the EGFP gene, via electrofusion. Subsequent simple sequence repeat (SSR), chloroplast simple sequence repeat and cleaved amplified polymorphic sequence analysis revealed that the two regenerated tetraploid plants were true allotetraploid somatic hybrids possessing nuclear genomic DNA of both parents and cytoplasmic DNA from the callus parent, while the five regenerated diploid plants were cybrids containing nuclear DNA of the leaf parent and with complex segregation of cytoplasmic DNA. Furthermore, EGFP expression was compared in cells and protoplasts from mature leaves of these diploid cybrids and allotetraploid somatic hybrids. Results showed that the intensity of GFP fluorescence per cell or protoplast in diploid was generally brighter than in allotetraploid. Moreover, same hybridization signal was detected on allotetraploid and diploid plants by Southern blot analysis. By real-time RT-PCR and Western blot analysis, GFP expression level of the diploid cybrid was revealed significantly higher than that of the allotetraploid somatic hybrid. These results suggest that ploidy level conversion can affect transgene expression and citrus diploid cybrid and allotetraploid somatic hybrid represents another example of gene regulation coupled to ploidy.
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Affiliation(s)
- Shi-Xiao Xu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
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Fu W, Ma X, Tang Q, Mo C. Karyotype analysis and genetic variation of a mutant in Siraitia grosvenorii. Mol Biol Rep 2011; 39:1247-52. [PMID: 21603854 PMCID: PMC3249549 DOI: 10.1007/s11033-011-0855-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 05/12/2011] [Indexed: 11/29/2022]
Abstract
This study analyzed the differences in karyotype and genetic variation between a mutant and wild-type Siraitia grosvenorii. Genetic variation included changes in genome and gene expression by SRAP molecular markers. Results showed that wild-type S. grosvenorii was diploid, with a chromosome number of 2n = 2x = 28, whereas the mutant was tetraploid with a chromosome number of 2n = 4x = 56. 4573 DNA bands were obtained using 189 different primer combinations, 577 of which were polymorphic, averaging 3.1 bands for each primer pair, while 1998 pairs were identical. There were no apparent differences on bands amplified by most primer pairs. After comparing the diploid and tetraploid strains, the data generally indicated that the polymorphism would be quite low. 2917 cDNA bands were generated using 133 primer combinations, and stable and clearly differential fragments were sorted out, cloned and sequenced. Ninety-two differentially expressed fragments were successfully sequenced. Sequence analysis showed that most fragments had significant homologous nucleotide sequences with resistant to stress and photosynthesis genes, including ribulose-1,5-bisphosphate carboxylase/oxygenase, phosphoenolpyruvate carboxykinase, pyruvate kinase, peroxisomal membrane transporter, NBS-LRR type resistance protein, protein phosphatase and others. The results revealed that the tetraploid strain has more resistant and photosynthesis ability than its diploid relatives, which providing reference information and resources for molecular breeding and seedless Luohanguo.
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Affiliation(s)
- Wei Fu
- Institute of Medicinal Plant Development, China Academy Medicinal Science, Chinese Peking Union Medical College, 100193 Beijing, People's Republic of China
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Lee SS, Lee SA, Yang J, Kim J. Developing stable progenies of ×Brassicoraphanus, an intergeneric allopolyploid between Brassica rapa and Raphanus sativus, through induced mutation using microspore culture. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2011; 122:885-91. [PMID: 21113703 DOI: 10.1007/s00122-010-1494-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Accepted: 11/07/2010] [Indexed: 05/03/2023]
Abstract
Induced mutations were used to improve the low seed fertility of an intergeneric allopolyploid, 'Baemoochae,' ×Brassicoraphanus, synthesized following hybridization between Brassica rapa and Raphanus sativus. The mutagen N-methyl-N-nitroso-urethane (NMU) was added to microspore cultures. Four lines of nine in the Mi(2) generation showed very high fertility under controlled pollination. The progeny lines (Mi(3)) confirmed this result under open pollination, and excellent uniformity was observed in plants grown in the field, as well as in their AFLP profile. On attaining high fertility and uniformity, one of the lines was released to farmers as a new leafy vegetable crop. The original nine lines shared very similar AFLP banding patterns, without any large differences between the high and low seed fertility lines. Thus, mutation induction accelerated genetic stabilization of a newly synthesized allopolyploid, ×Brassicoraphanus.
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Affiliation(s)
- Soo-Seong Lee
- BioBreeding Institute, Business Incubation, Chung-Ang University, Ansung, Gyounggi, Korea.
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Chang PL, Dilkes BP, McMahon M, Comai L, Nuzhdin SV. Homoeolog-specific retention and use in allotetraploid Arabidopsis suecica depends on parent of origin and network partners. Genome Biol 2010; 11:R125. [PMID: 21182768 PMCID: PMC3046485 DOI: 10.1186/gb-2010-11-12-r125] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Revised: 11/06/2010] [Accepted: 12/23/2010] [Indexed: 01/17/2023] Open
Abstract
Background Allotetraploids carry pairs of diverged homoeologs for most genes. With the genome doubled in size, the number of putative interactions is enormous. This poses challenges on how to coordinate the two disparate genomes, and creates opportunities by enhancing the phenotypic variation. New combinations of alleles co-adapt and respond to new environmental pressures. Three stages of the allopolyploidization process - parental species divergence, hybridization, and genome duplication - have been well analyzed. The last stage of evolutionary adjustments remains mysterious. Results Homoeolog-specific retention and use were analyzed in Arabidopsis suecica (As), a species derived from A. thaliana (At) and A. arenosa (Aa) in a single event 12,000 to 300,000 years ago. We used 405,466 diagnostic features on tiling microarrays to recognize At and Aa contributions to the As genome and transcriptome: 324 genes lacked Aa contributions and 614 genes lacked At contributions within As. In leaf tissues, 3,458 genes preferentially expressed At homoeologs while 4,150 favored Aa homoeologs. These patterns were validated with resequencing. Genes with preferential use of Aa homoeologs were enriched for expression functions, consistent with the dominance of Aa transcription. Heterologous networks - mixed from At and Aa transcripts - were underrepresented. Conclusions Thousands of deleted and silenced homoeologs in the genome of As were identified. Since heterologous networks may be compromised by interspecies incompatibilities, these networks evolve co-biases, expressing either only Aa or only At homoeologs. This progressive change towards predominantly pure parental networks might contribute to phenotypic variability and plasticity, and enable the species to exploit a larger range of environments.
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Affiliation(s)
- Peter L Chang
- Molecular and Computational Biology, University of Southern California, 1050 Childs Way, RRI 201, Los Angeles, CA 90089-2910, USA.
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Akhunova AR, Matniyazov RT, Liang H, Akhunov ED. Homoeolog-specific transcriptional bias in allopolyploid wheat. BMC Genomics 2010; 11:505. [PMID: 20849627 PMCID: PMC2997001 DOI: 10.1186/1471-2164-11-505] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Accepted: 09/17/2010] [Indexed: 12/18/2022] Open
Abstract
Background Interaction between parental genomes is accompanied by global changes in gene expression which, eventually, contributes to growth vigor and the broader phenotypic diversity of allopolyploid species. In order to gain a better understanding of the effects of allopolyploidization on the regulation of diverged gene networks, we performed a genome-wide analysis of homoeolog-specific gene expression in re-synthesized allohexaploid wheat created by the hybridization of a tetraploid derivative of hexaploid wheat with the diploid ancestor of the wheat D genome Ae. tauschii. Results Affymetrix wheat genome arrays were used for both the discovery of divergent homoeolog-specific mutations and analysis of homoeolog-specific gene expression in re-synthesized allohexaploid wheat. More than 34,000 detectable parent-specific features (PSF) distributed across the wheat genome were used to assess AB genome (could not differentiate A and B genome contributions) and D genome parental expression in the allopolyploid transcriptome. In re-synthesized polyploid 81% of PSFs detected mid-parent levels of gene expression, and only 19% of PSFs showed the evidence of non-additive expression. Non-additive expression in both AB and D genomes was strongly biased toward up-regulation of parental type of gene expression with only 6% and 11% of genes, respectively, being down-regulated. Of all the non-additive gene expression, 84% can be explained by differences in the parental genotypes used to make the allopolyploid. Homoeolog-specific co-regulation of several functional gene categories was found, particularly genes involved in photosynthesis and protein biosynthesis in wheat. Conclusions Here, we have demonstrated that the establishment of interactions between the diverged regulatory networks in allopolyploids is accompanied by massive homoeolog-specific up- and down-regulation of gene expression. This study provides insights into interactions between homoeologous genomes and their role in growth vigor, development, and fertility of allopolyploid species.
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Affiliation(s)
- Alina R Akhunova
- Department of Plant Pathology, Throckmorton Plant Sciences Center, Kansas State University, Manhattan, KS 66506, USA.
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Chagué V, Just J, Mestiri I, Balzergue S, Tanguy AM, Huneau C, Huteau V, Belcram H, Coriton O, Jahier J, Chalhoub B. Genome-wide gene expression changes in genetically stable synthetic and natural wheat allohexaploids. THE NEW PHYTOLOGIST 2010; 187:1181-1194. [PMID: 20591055 DOI: 10.1111/j.1469-8137.2010.03339.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
*The present study aims to understand regulation of gene expression in synthetic and natural wheat (Triticum aestivum) allohexaploids, that combines the AB genome of Triticum turgidum and the D genome of Aegilops tauschii; and which we have recently characterized as genetically stable. *We conducted a comprehensive genome-wide analysis of gene expression that allowed characterization of the effect of variability of the D genome progenitor, the intergenerational stability as well as the comparison with natural wheat allohexaploid. We used the Affymetrix GeneChip Wheat Genome Array, on which 55 049 transcripts are represented. *Additive expression was shown to represent the majority of expression regulation in the synthetic allohexaploids, where expression for more than c. 93% of transcripts was equal to the mid-parent value measured from a mixture of parental RNA. This leaves c. 2000 (c. 7%) transcripts, in which expression was nonadditive. No global gene expression bias or dominance towards any of the progenitor genomes was observed whereas high intergenerational stability and low effect of the D genome progenitor variability were revealed. *Our study suggests that gene expression regulation in wheat allohexaploids is established early upon allohexaploidization and highly conserved over generations, as demonstrated by the high similarity of expression with natural wheat allohexaploids.
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Affiliation(s)
- Véronique Chagué
- Organization and Evolution of Plant Genomes (OEPG), Unité de Recherche en Génomique Végétale (URGV), UMR INRA 1165 - CNRS 8114 - UEVE, F-91057 Evry Cedex, France
| | - Jérémy Just
- Organization and Evolution of Plant Genomes (OEPG), Unité de Recherche en Génomique Végétale (URGV), UMR INRA 1165 - CNRS 8114 - UEVE, F-91057 Evry Cedex, France
| | - Imen Mestiri
- Organization and Evolution of Plant Genomes (OEPG), Unité de Recherche en Génomique Végétale (URGV), UMR INRA 1165 - CNRS 8114 - UEVE, F-91057 Evry Cedex, France
| | - Sandrine Balzergue
- Organization and Evolution of Plant Genomes (OEPG), Unité de Recherche en Génomique Végétale (URGV), UMR INRA 1165 - CNRS 8114 - UEVE, F-91057 Evry Cedex, France
| | - Anne-Marie Tanguy
- Unité Mixte de Recherches INRA - Agrocampus Rennes, Amélioration des Plantes & Biotechnologies Végétales, F-35653 Le Rheu, France
| | - Cecile Huneau
- Organization and Evolution of Plant Genomes (OEPG), Unité de Recherche en Génomique Végétale (URGV), UMR INRA 1165 - CNRS 8114 - UEVE, F-91057 Evry Cedex, France
| | - Virginie Huteau
- Unité Mixte de Recherches INRA - Agrocampus Rennes, Amélioration des Plantes & Biotechnologies Végétales, F-35653 Le Rheu, France
| | - Harry Belcram
- Organization and Evolution of Plant Genomes (OEPG), Unité de Recherche en Génomique Végétale (URGV), UMR INRA 1165 - CNRS 8114 - UEVE, F-91057 Evry Cedex, France
| | - Olivier Coriton
- Unité Mixte de Recherches INRA - Agrocampus Rennes, Amélioration des Plantes & Biotechnologies Végétales, F-35653 Le Rheu, France
| | - Joseph Jahier
- Unité Mixte de Recherches INRA - Agrocampus Rennes, Amélioration des Plantes & Biotechnologies Végétales, F-35653 Le Rheu, France
| | - Boulos Chalhoub
- Organization and Evolution of Plant Genomes (OEPG), Unité de Recherche en Génomique Végétale (URGV), UMR INRA 1165 - CNRS 8114 - UEVE, F-91057 Evry Cedex, France
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Chelaifa H, Mahé F, Ainouche M. Transcriptome divergence between the hexaploid salt-marsh sister species Spartina maritima and Spartina alterniflora (Poaceae). Mol Ecol 2010; 19:2050-63. [PMID: 20550634 DOI: 10.1111/j.1365-294x.2010.04637.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Invasive species are ideal model systems to investigate the evolutionary processes associated with their ecological success by comparison with closely related species. In this article, we explore transcriptome evolution following divergence between two closely related salt-marsh species, the invasive Spartina alterniflora (native to the East-American Atlantic coast, introduced in several continents) and the declining Spartina maritima (native to the Euro-African Atlantic coast). We have explored the utility of cross-species hybridization microarrays using rice (Oryza sativa) oligo-microarrays to compare leaf expression patterns between these species. Coding sequence comparisons from 10 nuclear genes (2256 bp) revealed that nucleotide divergence between Spartina and Oryza range from 8% to 14%. More than 70% of the 60-mer oligonucleotide sequences spotted on the rice microarray exhibited stable and repeatable patterns when hybridized against Spartina RNA. In total, 9353 (44.5%) genes on the array hybridized with both species S. maritima and S. alterniflora. Among these genes, 1247 genes were found to be differentially expressed between the two Spartina species, most of them (957) being up-regulated in S. alterniflora. In particular, developmental and cellular growth genes (gene ontology, biological process) were highly up-regulated in S. alterniflora and down-regulated in S. maritima, whereas genes involved in stress response were up-regulated in S. maritima. Our findings indicate the suitability of cross-species microarray hybridization between Spartina and O. sativa and reveal the extent of leaf transcriptome evolution that took place during the divergence between S. alterniflora and S. maritima. Expression patterns are consistent with the morphological differentiation and differential expansion of the two species.
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Affiliation(s)
- H Chelaifa
- UMR CNRS 6553 University of Rennes 1, Bât. 14A Campus de Beaulieu, 35 042 Rennes Cedex, France
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Marmagne A, Brabant P, Thiellement H, Alix K. Analysis of gene expression in resynthesized Brassica napus allotetraploids: transcriptional changes do not explain differential protein regulation. THE NEW PHYTOLOGIST 2010; 186:216-27. [PMID: 20100210 DOI: 10.1111/j.1469-8137.2009.03139.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Polyploidy, or whole genome duplication, is a major evolutionary process that has shaped eukaryotic genomes, notably those of flowering plants. The mechanisms underlying the regulation of, and sharing of functions between, the duplicated genes originating from polyploidy events, which lead to novel phenotypes, remain to be elucidated. A previous comparative proteomic study identified 360 proteins that were differentially regulated between the diploid Brassica progenitors and their synthetic allotetraploid derivatives. For 102 of these proteins, using the same resynthesized Brassica napus allotetraploids, we assayed the accumulation of the transcripts of the corresponding genes. We compared transcript levels quantified in the synthetic allotetraploids with the mid-parent expression values. Although all of the genes surveyed encoded nonadditive proteins, we found that two-thirds of them had additive transcript levels, indicating that most of the differential protein regulation is not explained by transcriptional changes. Our data suggest that differential protein regulation is mainly governed by post-transcriptional modifications. Summarizing available data from transcriptomic studies of other synthetic allopolyploid models, we describe the general trends of transcript regulation in an allopolyploid genome and discuss putative underlying molecular mechanisms, with particular emphasis on the small RNA pathway for the post-transcriptional control of gene expression.
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Affiliation(s)
- Anne Marmagne
- CNRS, Ferme du Moulon, F-91190 Gif-sur-Yvette, France
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Chelaifa H, Monnier A, Ainouche M. Transcriptomic changes following recent natural hybridization and allopolyploidy in the salt marsh species Spartina x townsendii and Spartina anglica (Poaceae). THE NEW PHYTOLOGIST 2010; 186:161-74. [PMID: 20149114 DOI: 10.1111/j.1469-8137.2010.03179.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Allopolyploidy results from two events: the merger of divergent genomes and genome duplication. Both events have important functional consequences for the evolution and adaptation of newly formed allopolyploid species. In spite of the significant progress made in recent years, few studies have decoupled the effects of hybridization from genome duplication in the observed patterns of expression changes accompanying allopolyploidy in natural conditions. We used Agilent rice oligomicroarrays to explore gene expression changes following allopolyploidy in Spartina that includes a classic example of recent allopolyploid speciation: S. anglica formed during the 19th century following genome duplication of the hybrid S. x townsendii. Our data indicate important, but different, effects of hybridization and genome duplication in the expression patterns of the hybrid and allopolyploid. Deviation from parental additivity was most important following hybridization and was accompanied by maternal expression dominance, although transgressively expressed genes were also encountered. Maternal dominance was attenuated following genome duplication in S. anglica, but this species exhibits an increased number of transgressively overexpressed genes. These results reflect the decoupled effects of the 'genomic shock' following hybridization and genome redundancy on the genetic, epigenetic and regulatory mechanisms characterizing transcriptomic evolution in allopolyploids.
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Affiliation(s)
- Houda Chelaifa
- UMR CNRS 6553, Université de Rennes 1, 35042 Rennes Cedex, France
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