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Awan MJA, Farooq MA, Naqvi RZ, Karamat U, Bukhari SAR, Waqas MAB, Mahmood MA, Buzdar MI, Rasheed A, Amin I, Saeed NA, Mansoor S. Deciphering the differential expression patterns of yield-related negative regulators in hexaploid wheat cultivars and hybrids at different growth stages. Mol Biol Rep 2024; 51:537. [PMID: 38642174 DOI: 10.1007/s11033-024-09454-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 03/18/2024] [Indexed: 04/22/2024]
Abstract
BACKGROUND Hexaploid bread wheat underwent a series of polyploidization events through interspecific hybridizations that conferred adaptive plasticity and resulted in duplication and neofunctionalization of major agronomic genes. The genetic architecture of polyploid wheat not only confers adaptive plasticity but also offers huge genetic diversity. However, the contribution of different gene copies (homeologs) encoded from different subgenomes (A, B, D) at different growth stages remained unexplored. METHODS In this study, hybrid of elite cultivars of wheat were developed via reciprocal crosses (cytoplasm swapping) and phenotypically evaluated. We assessed differential expression profiles of yield-related negative regulators in these cultivars and their F1 hybrids and identified various cis-regulatory signatures by employing bioinformatics tools. Furthermore, the preferential expression patterns of the syntenic triads encoded from A, B, and D subgenomes were assessed to decipher their functional redundancy at six different growth stages. RESULTS Hybrid progenies showed better heterosis such as up to 17% increase in the average number of grains and up to 50% increase in average thousand grains weight as compared to mid-parents. Based on the expression profiling, our results indicated significant dynamic transcriptional expression patterns, portraying the different homeolog-dominance at the same stage in the different cultivars and their hybrids. Albeit belonging to same syntenic triads, a dynamic trend was observed in the regulatory signatures of these genes that might be influencing their expression profiles. CONCLUSION These findings can substantially contribute and provide insights for the selective introduction of better cultivars into traditional and hybrid breeding programs which can be harnessed for the improvement of future wheat.
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Affiliation(s)
- Muhammad Jawad Akbar Awan
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
| | - Muhammad Awais Farooq
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding, China
| | - Rubab Zahra Naqvi
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
| | - Umer Karamat
- State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding, China
- Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Sayyad Ali Raza Bukhari
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia
- Department of Biotechnology, University of Sargodha, Sargodha, Pakistan
| | - Muhammad Abu Bakar Waqas
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
| | - Muhammad Arslan Mahmood
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
| | - Muhammad Ismail Buzdar
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
| | - Awais Rasheed
- Department of Plant Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
- Institute of Crop Science, Chinese Academy of Agricultural Sciences (CAAS) & CIMMYT-China office, 12 Zhongguancun South Street, Beijing, 100081, China
| | - Imran Amin
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
| | - Nasir A Saeed
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan
| | - Shahid Mansoor
- Agricultural Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Constituent College of Pakistan Institute of Engineering and Applied Sciences, Jhang Road, Faisalabad, Pakistan.
- International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan.
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Yoo MJ, Koh J, Boatwright JL, Soltis DE, Soltis PS, Barbazuk WB, Chen S. Investigation of regulatory divergence between homoeologs in the recently formed allopolyploids, Tragopogon mirus and T. miscellus (Asteraceae). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 117:1191-1205. [PMID: 37997015 DOI: 10.1111/tpj.16553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/02/2023] [Accepted: 11/06/2023] [Indexed: 11/25/2023]
Abstract
Polyploidy is an important evolutionary process throughout eukaryotes, particularly in flowering plants. Duplicated gene pairs (homoeologs) in allopolyploids provide additional genetic resources for changes in molecular, biochemical, and physiological mechanisms that result in evolutionary novelty. Therefore, understanding how divergent genomes and their regulatory networks reconcile is vital for unraveling the role of polyploidy in plant evolution. Here, we compared the leaf transcriptomes of recently formed natural allotetraploids (Tragopogon mirus and T. miscellus) and their diploid parents (T. porrifolius X T. dubius and T. pratensis X T. dubius, respectively). Analysis of 35 400 expressed loci showed a significantly higher level of transcriptomic additivity compared to old polyploids; only 22% were non-additively expressed in the polyploids, with 5.9% exhibiting transgressive expression (lower or higher expression in the polyploids than in the diploid parents). Among approximately 7400 common orthologous regions (COREs), most loci in both allopolyploids exhibited expression patterns that were vertically inherited from their diploid parents. However, 18% and 20.3% of the loci showed novel expression bias patterns in T. mirus and T. miscellus, respectively. The expression changes of 1500 COREs were explained by cis-regulatory divergence (the condition in which the two parental subgenomes do not interact) between the diploid parents, whereas only about 423 and 461 of the gene expression changes represent trans-effects (the two parental subgenomes interact) in T. mirus and T. miscellus, respectively. The low degree of both non-additivity and trans-effects on gene expression may present the ongoing evolutionary processes of the newly formed Tragopogon polyploids (~80-90 years).
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Affiliation(s)
- Mi-Jeong Yoo
- Department of Biology, Clarkson University, Potsdam, New York, 13699, USA
| | - Jin Koh
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida, 32610, USA
| | - J Lucas Boatwright
- Plant and Environmental Science Department, Clemson University, Clemson, South Carolina, 29634, USA
| | - Douglas E Soltis
- Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
- Genetics Institute, University of Florida, Gainesville, Florida, 32610, USA
- Biodiversity Institute, University of Florida, Gainesville, Florida, 32611, USA
- Florida Museum of Natural History, University of Florida, Gainesville, Florida, 32611, USA
| | - Pamela S Soltis
- Genetics Institute, University of Florida, Gainesville, Florida, 32610, USA
- Biodiversity Institute, University of Florida, Gainesville, Florida, 32611, USA
- Florida Museum of Natural History, University of Florida, Gainesville, Florida, 32611, USA
| | - W Brad Barbazuk
- Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
- Genetics Institute, University of Florida, Gainesville, Florida, 32610, USA
| | - Sixue Chen
- Department of Biology, University of Mississippi, Oxford, Mississippi, 38677, USA
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3
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Katayama N, Yamamoto T, Aiuchi S, Watano Y, Fujiwara T. Subgenome evolutionary dynamics in allotetraploid ferns: insights from the gene expression patterns in the allotetraploid species Phegopteris decursivepinnata (Thelypteridacea, Polypodiales). FRONTIERS IN PLANT SCIENCE 2024; 14:1286320. [PMID: 38264021 PMCID: PMC10803465 DOI: 10.3389/fpls.2023.1286320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 12/13/2023] [Indexed: 01/25/2024]
Abstract
Allopolyploidization often leads to disruptive conflicts among more than two sets of subgenomes, leading to genomic modifications and changes in gene expression. Although the evolutionary trajectories of subgenomes in allopolyploids have been studied intensely in angiosperms, the dynamics of subgenome evolution remain poorly understood in ferns, despite the prevalence of allopolyploidization. In this study, we have focused on an allotetraploid fern-Phegopteris decursivepinnata-and its diploid parental species, P. koreana (K) and P. taiwaniana (T). Using RNA-seq analyses, we have compared the gene expression profiles for 9,540 genes among parental species, synthetic F1 hybrids, and natural allotetraploids. The changes in gene expression patterns were traced from the F1 hybrids to the natural allopolyploids. This study has revealed that the expression patterns observed in most genes in the F1 hybrids are largely conserved in the allopolyploids; however, there were substantial differences in certain genes between these groups. In the allopolyploids compared with the F1 hybrids, the number of genes showing a transgressive pattern in total expression levels was increased. There was a slight reduction in T-dominance and a slight increase in K-dominance, in terms of expression level dominance. Interestingly, there is no obvious bias toward the T- or K-subgenomes in the number and expression levels overall, showing the absence of subgenome dominance. These findings demonstrated the impacts of the substantial transcriptome change after hybridization and the moderate modification during allopolyploid establishment on gene expression in ferns and provided important insights into subgenome evolution in polyploid ferns.
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Affiliation(s)
- Natsu Katayama
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Department of Biology, Faculty of Science, Chiba University, Chiba, Japan
| | - Takuya Yamamoto
- Department of Biology, Graduate School of Science, Chiba University, Chiba, Japan
| | - Sakura Aiuchi
- Department of Biology, Graduate School of Science, Chiba University, Chiba, Japan
| | - Yasuyuki Watano
- Department of Biology, Faculty of Science, Chiba University, Chiba, Japan
| | - Tao Fujiwara
- Center for Molecular Biodiversity Research, National Museum of Nature and Science, Tsukuba, Ibaraki, Japan
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4
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Fang C, Yang M, Tang Y, Zhang L, Zhao H, Ni H, Chen Q, Meng F, Jiang J. Dynamics of cis-regulatory sequences and transcriptional divergence of duplicated genes in soybean. Proc Natl Acad Sci U S A 2023; 120:e2303836120. [PMID: 37871213 PMCID: PMC10622917 DOI: 10.1073/pnas.2303836120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 09/19/2023] [Indexed: 10/25/2023] Open
Abstract
Transcriptional divergence of duplicated genes after whole genome duplication (WGD) has been described in many plant lineages and is often associated with subgenome dominance, a genome-wide mechanism. However, it is unknown what underlies the transcriptional divergence of duplicated genes in polyploid species that lack subgenome dominance. Soybean is a paleotetraploid with a WGD that occurred 5 to 13 Mya. Approximately 50% of the duplicated genes retained from this WGD exhibit transcriptional divergence. We developed accessible chromatin region (ACR) datasets from leaf, flower, and seed tissues using MNase-hypersensitivity sequencing. We validated enhancer function of several ACRs associated with known genes using CRISPR/Cas9-mediated genome editing. The ACR datasets were used to examine and correlate the transcriptional patterns of 17,111 pairs of duplicated genes in different tissues. We demonstrate that ACR dynamics are correlated with divergence of both expression level and tissue specificity of individual gene pairs. Gain or loss of flanking ACRs and mutation of cis-regulatory elements (CREs) within the ACRs can change the balance of the expression level and/or tissue specificity of the duplicated genes. Analysis of DNA sequences associated with ACRs revealed that the extensive sequence rearrangement after the WGD reshaped the CRE landscape, which appears to play a key role in the transcriptional divergence of duplicated genes in soybean. This may represent a general mechanism for transcriptional divergence of duplicated genes in polyploids that lack subgenome dominance.
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Affiliation(s)
- Chao Fang
- Department of Plant Biology, Michigan State University, East Lansing, MI48824
| | - Mingyu Yang
- Northeast Institute of Geography and Agroecology, Key Laboratory of Soybean Molecular Design Breeding, Chinese Academy of Sciences, Harbin150081, China
- Key Laboratory of Soybean Biology in Chinese Ministry of Education, Northeast Agricultural University, Harbin150030, China
| | - Yuecheng Tang
- Northeast Institute of Geography and Agroecology, Key Laboratory of Soybean Molecular Design Breeding, Chinese Academy of Sciences, Harbin150081, China
- Key Laboratory of Soybean Biology in Chinese Ministry of Education, Northeast Agricultural University, Harbin150030, China
| | - Ling Zhang
- Agro-Biotechnology Research Institute, Jilin Academy of Agricultural Sciences, Changchun130033, China
| | - Hainan Zhao
- Department of Plant Biology, Michigan State University, East Lansing, MI48824
| | - Hejia Ni
- Key Laboratory of Soybean Biology in Chinese Ministry of Education, Northeast Agricultural University, Harbin150030, China
| | - Qingshan Chen
- Key Laboratory of Soybean Biology in Chinese Ministry of Education, Northeast Agricultural University, Harbin150030, China
| | - Fanli Meng
- Northeast Institute of Geography and Agroecology, Key Laboratory of Soybean Molecular Design Breeding, Chinese Academy of Sciences, Harbin150081, China
| | - Jiming Jiang
- Department of Plant Biology, Michigan State University, East Lansing, MI48824
- Department of Horticulture, Michigan State University, East Lansing, MI48824
- Michigan State University AgBioResearch, East Lansing, MI48824
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5
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Bellec A, Sow MD, Pont C, Civan P, Mardoc E, Duchemin W, Armisen D, Huneau C, Thévenin J, Vernoud V, Depège-Fargeix N, Maunas L, Escale B, Dubreucq B, Rogowsky P, Bergès H, Salse J. Tracing 100 million years of grass genome evolutionary plasticity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023. [PMID: 36919199 DOI: 10.1111/tpj.16185] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/29/2023] [Accepted: 02/24/2023] [Indexed: 05/17/2023]
Abstract
Grasses derive from a family of monocotyledonous plants that includes crops of major economic importance such as wheat, rice, sorghum and barley, sharing a common ancestor some 100 million years ago. The genomic attributes of plant adaptation remain obscure and the consequences of recurrent whole genome duplications (WGD) or polyploidization events, a major force in plant evolution, remain largely speculative. We conducted a comparative analysis of omics data from ten grass species to unveil structural (inversions, fusions, fissions, duplications, substitutions) and regulatory (expression and methylation) basis of genome plasticity, as possible attributes of plant long lasting evolution and adaptation. The present study demonstrates that diverged polyploid lineages sharing a common WGD event often present the same patterns of structural changes and evolutionary dynamics, but these patterns are difficult to generalize across independent WGD events as a result of non-WGD factors such as selection and domestication of crops. Polyploidy is unequivocally linked to the evolutionary success of grasses during the past 100 million years, although it remains difficult to attribute this success to particular genomic consequences of polyploidization, suggesting that polyploids harness the potential of genome duplication, at least partially, in lineage-specific ways. Overall, the present study clearly demonstrates that post-polyploidization reprogramming is more complex than traditionally reported in investigating single species and calls for a critical and comprehensive comparison across independently polyploidized lineages.
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Affiliation(s)
- Arnaud Bellec
- INRAE/CNRGV US 1258, 24 Chemin de Borde Rouge, 31320, Auzeville-Tolosane, France
| | - Mamadou Dia Sow
- UCA, INRAE, GDEC, 5 Chemin de Beaulieu, 63000, Clermont-Ferrand, France
| | - Caroline Pont
- UCA, INRAE, GDEC, 5 Chemin de Beaulieu, 63000, Clermont-Ferrand, France
| | - Peter Civan
- UCA, INRAE, GDEC, 5 Chemin de Beaulieu, 63000, Clermont-Ferrand, France
| | - Emile Mardoc
- UCA, INRAE, GDEC, 5 Chemin de Beaulieu, 63000, Clermont-Ferrand, France
| | | | - David Armisen
- UCA, INRAE, GDEC, 5 Chemin de Beaulieu, 63000, Clermont-Ferrand, France
| | - Cécile Huneau
- UCA, INRAE, GDEC, 5 Chemin de Beaulieu, 63000, Clermont-Ferrand, France
| | - Johanne Thévenin
- INRAE/AgroParisTech-UMR 1318. Bat 2. Centre INRA de Versailles, route de Saint Cyr, 78026, Versailles CEDEX, France
| | - Vanessa Vernoud
- INRAE/CNRS/ENS/Univ. Lyon-UMR 879, 46 allée d'Italie, 69364, Lyon Cedex 07, France
| | | | - Laurent Maunas
- Arvalis-Institut du végétal, 21 chemin de Pau, 64121 Montardon, France
| | - Brigitte Escale
- Arvalis-Institut du végétal, 21 chemin de Pau, 64121 Montardon, France
- Direction de l'agriculture de Polynésie française, Route de l'Hippodrome, 98713, Papeete, France
| | - Bertrand Dubreucq
- INRAE/AgroParisTech-UMR 1318. Bat 2. Centre INRA de Versailles, route de Saint Cyr, 78026, Versailles CEDEX, France
| | - Peter Rogowsky
- INRAE/CNRS/ENS/Univ. Lyon-UMR 879, 46 allée d'Italie, 69364, Lyon Cedex 07, France
| | - Hélène Bergès
- INRAE/CNRGV US 1258, 24 Chemin de Borde Rouge, 31320, Auzeville-Tolosane, France
| | - Jerome Salse
- UCA, INRAE, GDEC, 5 Chemin de Beaulieu, 63000, Clermont-Ferrand, France
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6
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Pelosi JA, Kim EH, Barbazuk WB, Sessa EB. Phylotranscriptomics Illuminates the Placement of Whole Genome Duplications and Gene Retention in Ferns. FRONTIERS IN PLANT SCIENCE 2022; 13:882441. [PMID: 35909764 PMCID: PMC9330400 DOI: 10.3389/fpls.2022.882441] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 06/16/2022] [Indexed: 05/31/2023]
Abstract
Ferns are the second largest clade of vascular plants with over 10,000 species, yet the generation of genomic resources for the group has lagged behind other major clades of plants. Transcriptomic data have proven to be a powerful tool to assess phylogenetic relationships, using thousands of markers that are largely conserved across the genome, and without the need to sequence entire genomes. We assembled the largest nuclear phylogenetic dataset for ferns to date, including 2884 single-copy nuclear loci from 247 transcriptomes (242 ferns, five outgroups), and investigated phylogenetic relationships across the fern tree, the placement of whole genome duplications (WGDs), and gene retention patterns following WGDs. We generated a well-supported phylogeny of ferns and identified several regions of the fern phylogeny that demonstrate high levels of gene tree-species tree conflict, which largely correspond to areas of the phylogeny that have been difficult to resolve. Using a combination of approaches, we identified 27 WGDs across the phylogeny, including 18 large-scale events (involving more than one sampled taxon) and nine small-scale events (involving only one sampled taxon). Most inferred WGDs occur within single lineages (e.g., orders, families) rather than on the backbone of the phylogeny, although two inferred events are shared by leptosporangiate ferns (excluding Osmundales) and Polypodiales (excluding Lindsaeineae and Saccolomatineae), clades which correspond to the majority of fern diversity. We further examined how retained duplicates following WGDs compared across independent events and found that functions of retained genes were largely convergent, with processes involved in binding, responses to stimuli, and certain organelles over-represented in paralogs while processes involved in transport, organelles derived from endosymbiotic events, and signaling were under-represented. To date, our study is the most comprehensive investigation of the nuclear fern phylogeny, though several avenues for future research remain unexplored.
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Affiliation(s)
- Jessie A. Pelosi
- Department of Biology, University of Florida, Gainesville, FL, United States
| | - Emily H. Kim
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, United States
| | - W. Brad Barbazuk
- Department of Biology, University of Florida, Gainesville, FL, United States
- Genetics Institute, University of Florida, Gainesville, FL, United States
| | - Emily B. Sessa
- Department of Biology, University of Florida, Gainesville, FL, United States
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7
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Behling AH, Winter DJ, Ganley ARD, Cox MP. Cross-kingdom transcriptomic trends in the evolution of hybrid gene expression. J Evol Biol 2022; 35:1126-1137. [PMID: 35830478 PMCID: PMC9546207 DOI: 10.1111/jeb.14059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 06/13/2022] [Indexed: 11/29/2022]
Abstract
Hybridization is a route to speciation that occurs widely across the eukaryote tree of life. The success of allopolyploids (hybrid species with increased ploidy) and homoploid hybrids (with unchanged ploidy) is well documented. However, their formation and establishment is not straightforward, with a suite of near‐instantaneous and longer term biological repercussions faced by the new species. Central to these challenges is the rewiring of gene regulatory networks following the merger of distinct genomes inherited from both parental species. Research on the evolution of hybrid gene expression has largely involved studies on a single hybrid species or a few gene families. Here, we present the first standardized transcriptome‐wide study exploring the fates of genes following hybridization across three kingdoms: animals, plants and fungi. Within each kingdom, we pair an allopolyploid system with a closely related homoploid hybrid to decouple the influence of increased ploidy from genome merger. Genome merger, not changes in ploidy, has the greatest effect on posthybridization expression patterns across all study systems. Strikingly, we find that differentially expressed genes in parent species preferentially switch to more similar expression in hybrids across all kingdoms, likely as a consequence of regulatory trans‐acting cross‐talk within the hybrid nucleus. We also highlight the prevalence of gene loss or silencing among extremely differentially expressed genes in hybrid species across all kingdoms. These shared patterns suggest that the evolutionary process of hybridization leads to common high‐level expression outcomes, regardless of the particular species or kingdom.
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Affiliation(s)
- Anna H Behling
- School of Natural Sciences, Massey University, Palmerston North, New Zealand
| | - David J Winter
- School of Natural Sciences, Massey University, Palmerston North, New Zealand
| | - Austen R D Ganley
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Murray P Cox
- School of Natural Sciences, Massey University, Palmerston North, New Zealand
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8
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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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9
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Huang X, Wang W, Gong T, Wickell D, Kuo LY, Zhang X, Wen J, Kim H, Lu F, Zhao H, Chen S, Li H, Wu W, Yu C, Chen S, Fan W, Chen S, Bao X, Li L, Zhang D, Jiang L, Khadka D, Yan X, Liao Z, Zhou G, Guo Y, Ralph J, Sederoff RR, Wei H, Zhu P, Li FW, Ming R, Li Q. The flying spider-monkey tree fern genome provides insights into fern evolution and arborescence. NATURE PLANTS 2022; 8:500-512. [PMID: 35534720 PMCID: PMC9122828 DOI: 10.1038/s41477-022-01146-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 03/30/2022] [Indexed: 05/03/2023]
Abstract
To date, little is known about the evolution of fern genomes, with only two small genomes published from the heterosporous Salviniales. Here we assembled the genome of Alsophila spinulosa, known as the flying spider-monkey tree fern, onto 69 pseudochromosomes. The remarkable preservation of synteny, despite resulting from an ancient whole-genome duplication over 100 million years ago, is unprecedented in plants and probably speaks to the uniqueness of tree ferns. Our detailed investigations into stem anatomy and lignin biosynthesis shed new light on the evolution of stem formation in tree ferns. We identified a phenolic compound, alsophilin, that is abundant in xylem, and we provided the molecular basis for its biosynthesis. Finally, analysis of demographic history revealed two genetic bottlenecks, resulting in rapid demographic declines of A. spinulosa. The A. spinulosa genome fills a crucial gap in the plant genomic landscape and helps elucidate many unique aspects of tree fern biology.
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Affiliation(s)
- Xiong Huang
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Wenling Wang
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Ting Gong
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines; NHC Key Laboratory of Biosynthesis of Natural Products; CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - David Wickell
- Thompson Institute, Ithaca, NY, USA
- Plant Biology Section, Cornell University, Ithaca, NY, USA
| | - Li-Yaung Kuo
- Institute of Molecular & Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Xingtan Zhang
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Jialong Wen
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, China
| | - Hoon Kim
- Department of Biochemistry and DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Fachuang Lu
- Department of Biochemistry and DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Hansheng Zhao
- State Forestry Administration Key Open Laboratory on the Science and Technology of Bamboo and Rattan, Institute of Gene for Bamboo and Rattan Resources, International Center for Bamboo and Rattan, Beijing, China
| | - Song Chen
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Hui Li
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Wenqi Wu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
| | - Changjiang Yu
- College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, China
| | - Su Chen
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Wei Fan
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Shuai Chen
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Xiuqi Bao
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines; NHC Key Laboratory of Biosynthesis of Natural Products; CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Li Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines; NHC Key Laboratory of Biosynthesis of Natural Products; CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Dan Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines; NHC Key Laboratory of Biosynthesis of Natural Products; CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Longyu Jiang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines; NHC Key Laboratory of Biosynthesis of Natural Products; CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Dipak Khadka
- GoldenGate International College, Tribhuvan University, Battisputali, Kathmandu, Nepal
| | - Xiaojing Yan
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China
| | - Zhenyang Liao
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Gongke Zhou
- College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, China
| | - Yalong Guo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Science, Beijing, China
| | - John Ralph
- Department of Biochemistry and DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Ronald R Sederoff
- Forest Biotechnology Group, Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC, USA
| | - Hairong Wei
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, USA.
| | - Ping Zhu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines; NHC Key Laboratory of Biosynthesis of Natural Products; CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
| | - Fay-Wei Li
- Thompson Institute, Ithaca, NY, USA.
- Plant Biology Section, Cornell University, Ithaca, NY, USA.
| | - Ray Ming
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Quanzi Li
- State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, China.
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10
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Zhang W, Liao L, Xu J, Han Y, Li L. Genome-wide identification, characterization and expression analysis of MATE family genes in apple (Malus × domestica Borkh). BMC Genomics 2021; 22:632. [PMID: 34461821 PMCID: PMC8406601 DOI: 10.1186/s12864-021-07943-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 08/12/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND As an important group of the multidrug efflux transporter family, the multidrug and toxic compound extrusion (MATE) family has a wide range of functions and is distributed in all kingdoms of living organisms. However, only two MATE genes in apple have been analyzed and genome-wide comprehensive analysis of MATE family is needed. RESULTS In this study, a total of 66 MATE (MdMATE) candidates encoding putative MATE transporters were identified in the apple genome. These MdMATE genes were classified into four groups by phylogenetic analysis with MATE genes in Arabidopsis. Synteny analysis reveals that whole genome duplication (WGD) and segmental duplication events played a major role in the expansion of MATE gene family in apple. MdMATE genes show diverse expression patterns in different tissues/organs and developmental stages. Analysis of cis-regulatory elements in MdMATE promoter regions indicates that the function of MdMATE genes is mainly related to stress response. Besides, the changes of gene expression levels upon different pathogen infections reveal that MdMATE genes are involved in biotic stress response. CONCLUSIONS In this work, we systematically identified MdMATE genes in apple genome using a set of bioinformatics approaches. Our comprehensive analysis provided valuable resources for improving disease resistance in apple and further functional characterization of MATE genes in other species.
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Affiliation(s)
- Weihan Zhang
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Liao Liao
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430074, People's Republic of China
| | - Jinsheng Xu
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Yuepeng Han
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430074, People's Republic of China
| | - Li Li
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China. .,Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
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11
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Boatwright JL, Yeh CT, Hu HC, Susanna A, Soltis DE, Soltis PS, Schnable PS, Barbazuk WB. Trajectories of Homoeolog-Specific Expression in Allotetraploid Tragopogon castellanus Populations of Independent Origins. FRONTIERS IN PLANT SCIENCE 2021; 12:679047. [PMID: 34249049 PMCID: PMC8261302 DOI: 10.3389/fpls.2021.679047] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/20/2021] [Indexed: 06/13/2023]
Abstract
Polyploidization can have a significant ecological and evolutionary impact by providing substantially more genetic material that may result in novel phenotypes upon which selection may act. While the effects of polyploidization are broadly reviewed across the plant tree of life, the reproducibility of these effects within naturally occurring, independently formed polyploids is poorly characterized. The flowering plant genus Tragopogon (Asteraceae) offers a rare glimpse into the intricacies of repeated allopolyploid formation with both nascent (< 90 years old) and more ancient (mesopolyploids) formations. Neo- and mesopolyploids in Tragopogon have formed repeatedly and have extant diploid progenitors that facilitate the comparison of genome evolution after polyploidization across a broad span of evolutionary time. Here, we examine four independently formed lineages of the mesopolyploid Tragopogon castellanus for homoeolog expression changes and fractionation after polyploidization. We show that expression changes are remarkably similar among these independently formed polyploid populations with large convergence among expressed loci, moderate convergence among loci lost, and stochastic silencing. We further compare and contrast these results for T. castellanus with two nascent Tragopogon allopolyploids. While homoeolog expression bias was balanced in both nascent polyploids and T. castellanus, the degree of additive expression was significantly different, with the mesopolyploid populations demonstrating more non-additive expression. We suggest that gene dosage and expression noise minimization may play a prominent role in regulating gene expression patterns immediately after allopolyploidization as well as deeper into time, and these patterns are conserved across independent polyploid lineages.
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Affiliation(s)
- J. Lucas Boatwright
- Advanced Plant Technology Program, Clemson University, Clemson, SC, United States
| | - Cheng-Ting Yeh
- Department of Agronomy, Iowa State University, Ames, IA, United States
| | - Heng-Cheng Hu
- Department of Agronomy, Iowa State University, Ames, IA, United States
- Covance Inc., Indianapolis, IN, United States
| | - Alfonso Susanna
- Botanic Institute of Barcelona, Consejo Superior de Investigaciones Científicas, ICUB, Barcelona, Spain
| | - Douglas E. Soltis
- Department of Biology, University of Florida, Gainesville, FL, United States
- Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL, United States
- Florida Museum of Natural History, University of Florida, Gainesville, FL, United States
- Genetics Institute, University of Florida, Gainesville, FL, United States
- Biodiversity Institute, University of Florida, Gainesville, FL, United States
| | - Pamela S. Soltis
- Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL, United States
- Florida Museum of Natural History, University of Florida, Gainesville, FL, United States
- Genetics Institute, University of Florida, Gainesville, FL, United States
- Biodiversity Institute, University of Florida, Gainesville, FL, United States
| | | | - William B. Barbazuk
- Department of Biology, University of Florida, Gainesville, FL, United States
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12
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Peng Z, Chen H, Tan L, Shu H, Varshney RK, Zhou Z, Zhao Z, Luo Z, Chitikineni A, Wang L, Maku J, López Y, Gallo M, Zhou H, Wang J. Natural polymorphisms in a pair of NSP2 homoeologs can cause loss of nodulation in peanut. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:1104-1118. [PMID: 33130897 DOI: 10.1093/jxb/eraa505] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/27/2020] [Indexed: 06/11/2023]
Abstract
Microbial symbiosis in legumes is achieved through nitrogen-fixing root nodules, and these are important for sustainable agriculture. The molecular mechanisms underlying development of root nodules in polyploid legume crops are largely understudied. Through map-based cloning and QTL-seq approaches, we identified a pair of homoeologous GRAS transcription factor genes, Nodulation Signaling Pathway 2 (AhNSP2-B07 or Nb) and AhNSP2-A08 (Na), controlling nodulation in cultivated peanut (Arachis hypogaea L.), an allotetraploid legume crop, which exhibited non-Mendelian and Mendelian inheritance, respectively. The segregation of nodulation in the progeny of Nananbnb genotypes followed a 3:1 Mendelian ratio, in contrast to the 5:3~1:1 non-Mendelian ratio for nanaNbnb genotypes. Additionally, a much higher frequency of the nb allele (13%) than the na allele (4%) exists in the peanut germplasm collection, suggesting that Nb is less essential than Na in nodule organogenesis. Our findings reveal the genetic basis of naturally occurred non-nodulating peanut plants, which can be potentially used for nitrogen fixation improvement in peanut. Furthermore, the results have implications for and provide insights into the evolution of homoeologous genes in allopolyploid species.
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Affiliation(s)
- Ze Peng
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Huiqiong Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Lubin Tan
- Department of Plant Genetics and Breeding, China Agricultural University, Beijing, China
| | - Hongmei Shu
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Rajeev K Varshney
- Center of Excellence in Genomics and Systems Biology, International Crops Research Institute for the Semi-Arid Tropics, Patancheru, India
| | - Zhekai Zhou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Zifan Zhao
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Ziliang Luo
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Annapurna Chitikineni
- Center of Excellence in Genomics and Systems Biology, International Crops Research Institute for the Semi-Arid Tropics, Patancheru, India
| | - Liping Wang
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - James Maku
- Sciences and Mathematics Department, Glenville State College, Glenville, WV, USA
| | - Yolanda López
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Maria Gallo
- Delaware Valley University, Doylestown, PA, USA
| | - Hai Zhou
- Agronomy Department, University of Florida, Gainesville, FL, USA
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Jianping Wang
- Agronomy Department, University of Florida, Gainesville, FL, USA
- Genetics Institute, Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL, USA
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13
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Lee JS, Adams KL. Global insights into duplicated gene expression and alternative splicing in polyploid Brassica napus under heat, cold, and drought stress. THE PLANT GENOME 2020; 13:e20057. [PMID: 33043636 DOI: 10.1002/tpg2.20057] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 07/26/2020] [Accepted: 08/20/2020] [Indexed: 05/21/2023]
Abstract
Polyploidy has been a prevalent process during plant evolution and it has made a major impact on the structure and evolution of plant genomes. Many important crop plants are polyploid. There is considerable interest in expression patterns of duplicated genes in polyploids. Alternative splicing (AS) is a fundamental aspect of gene expression that produces multiple final transcript types from a single type of mRNAs. The effects of abiotic stress conditions on AS in polyploids has received little attention. We conducted a global transcriptome analysis of Brassica napus, an allotetraploid derived from B. rapa (AT ) and B. oleracea (CT ), by RNA-Seq of plants subjected to cold, heat, and drought stress treatments. Analyses of 27,360 pairs of duplicated genes revealed overall AT subgenome biases in gene expression and CT subgenome biases in the extent of alternative splicing under all three stress treatments. More genes increased in expression than decreased in response to the stresses. Negative correlations were found between expression levels and AS frequency for each type of AS. Cold stress produced the greatest changes in gene expression and AS. Cold-induced AS changes were more likely to be shared with those generated by drought than by heat stress. We used homeologs of FLC and CCA1 as case studies to show the dynamics of how duplicates in a polyploid respond to cold stress. Our results suggest that divergence in gene expression and AS patterns between duplicated genes may increase the flexibility of polyploids when responding to abiotic stressors.
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Affiliation(s)
- Joon Seon Lee
- Department of Botany, University of British Columbia, 6270 University Blvd, Vancouver, BC, V6T 1Z4, Canada
| | - Keith L Adams
- Department of Botany, University of British Columbia, 6270 University Blvd, Vancouver, BC, V6T 1Z4, Canada
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14
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Greenham K, Sartor RC, Zorich S, Lou P, Mockler TC, McClung CR. Expansion of the circadian transcriptome in Brassica rapa and genome-wide diversification of paralog expression patterns. eLife 2020; 9:e58993. [PMID: 32996462 PMCID: PMC7655105 DOI: 10.7554/elife.58993] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 09/29/2020] [Indexed: 02/02/2023] Open
Abstract
An important challenge of crop improvement strategies is assigning function to paralogs in polyploid crops. Here we describe the circadian transcriptome in the polyploid crop Brassica rapa. Strikingly, almost three-quarters of the expressed genes exhibited circadian rhythmicity. Genetic redundancy resulting from whole genome duplication is thought to facilitate evolutionary change through sub- and neo-functionalization among paralogous gene pairs. We observed genome-wide expansion of the circadian expression phase among retained paralogous pairs. Using gene regulatory network models, we compared transcription factor targets between B. rapa and Arabidopsis circadian networks to reveal evidence for divergence between B. rapa paralogs that may be driven in part by variation in conserved non-coding sequences (CNS). Additionally, differential drought response among retained paralogous pairs suggests further functional diversification. These findings support the rapid expansion and divergence of the transcriptional network in a polyploid crop and offer a new approach for assessing paralog activity at the transcript level.
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Affiliation(s)
- Kathleen Greenham
- Department of Plant and Microbial Biology, University of MinnesotaSaint PaulUnited States
| | - Ryan C Sartor
- Crop and Soil Sciences, North Carolina State UniversityRaleighUnited States
| | - Stevan Zorich
- Department of Plant and Microbial Biology, University of MinnesotaSaint PaulUnited States
| | - Ping Lou
- Department of Biological Sciences, Dartmouth CollegeHanoverUnited States
| | - Todd C Mockler
- Donald Danforth Plant Science CenterSt. LouisUnited States
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15
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Yang Y, Zheng C, Chandrasekaran U, Yu L, Liu C, Pu T, Wang X, Du J, Liu J, Yang F, Yong T, Yang W, Liu W, Shu K. Identification and Bioinformatic Analysis of the GmDOG1-Like Family in Soybean and Investigation of Their Expression in Response to Gibberellic Acid and Abscisic Acid. PLANTS 2020; 9:plants9080937. [PMID: 32722147 PMCID: PMC7465105 DOI: 10.3390/plants9080937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/24/2020] [Accepted: 07/21/2020] [Indexed: 11/16/2022]
Abstract
Seed germination is one of the most important stages during plant life cycle, and DOG1 (Delay of germination1) plays a pivotal regulatory role in seed dormancy and germination. In this study, we have identified the DOG1-Like (DOG1L) family in soybean (Glycine max), a staple oil crop worldwide, and investigated their chromosomal distribution, structure and expression patterns. The results showed that the GmDOG1L family is composed of 40 members, which can be divided into six subgroups, according to their evolutionary relationship with other known DOG1-Like genes. These GmDOG1Ls are distributed on 18 of 20 chromosomes in the soybean genome and the number of exons for all the 40 GmDOG1Ls varied greatly. Members of the different subgroups possess a similar motif structure composition. qRT-PCR assay showed that the expression patterns of different GmDOG1Ls were significantly altered in various tissues, and some GmDOG1Ls expressed primarily in soybean seeds. Gibberellic acid (GA) remarkably inhibited the expression of most of GmDOG1Ls, whereas Abscisic acid (ABA) inhibited some of the GmDOG1Ls expression while promoting others. It is speculated that some GmDOG1Ls regulate seed dormancy and germination by directly or indirectly relating to ABA and GA pathways, with complex interaction networks. This study provides an important theoretical basis for further investigation about the regulatory roles of GmDOG1L family on soybean seed germination.
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Affiliation(s)
- Yingzeng Yang
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
- School of Ecology and Environment, Northwestern Polytechnical University, Xi’an 710012, China;
| | - Chuan Zheng
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
- School of Ecology and Environment, Northwestern Polytechnical University, Xi’an 710012, China;
| | | | - Liang Yu
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Chunyan Liu
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Tian Pu
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Xiaochun Wang
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Junbo Du
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Jiang Liu
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Feng Yang
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Taiwen Yong
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Wenyu Yang
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
| | - Weiguo Liu
- Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu 611130, China; (Y.Y.); (C.Z.); (L.Y.); (C.L.); (T.P.); (X.W.); (J.D.); (J.L.); (F.Y.); (T.Y.); (W.Y.)
- Correspondence: (W.L.); (K.S.)
| | - Kai Shu
- School of Ecology and Environment, Northwestern Polytechnical University, Xi’an 710012, China;
- Correspondence: (W.L.); (K.S.)
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16
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VanBuren R, Man Wai C, Wang X, Pardo J, Yocca AE, Wang H, Chaluvadi SR, Han G, Bryant D, Edger PP, Messing J, Sorrells ME, Mockler TC, Bennetzen JL, Michael TP. Exceptional subgenome stability and functional divergence in the allotetraploid Ethiopian cereal teff. Nat Commun 2020; 11:884. [PMID: 32060277 PMCID: PMC7021729 DOI: 10.1038/s41467-020-14724-z] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 01/30/2020] [Indexed: 12/22/2022] Open
Abstract
Teff (Eragrostis tef) is a cornerstone of food security in the Horn of Africa, where it is prized for stress resilience, grain nutrition, and market value. Here, we report a chromosome-scale assembly of allotetraploid teff (variety Dabbi) and patterns of subgenome dynamics. The teff genome contains two complete sets of homoeologous chromosomes, with most genes maintaining as syntenic gene pairs. TE analysis allows us to estimate that the teff polyploidy event occurred ~1.1 million years ago (mya) and that the two subgenomes diverged ~5.0 mya. Despite this divergence, we detect no large-scale structural rearrangements, homoeologous exchanges, or biased gene loss, in contrast to many other allopolyploids. The two teff subgenomes have partitioned their ancestral functions based on divergent expression across a diverse expression atlas. Together, these genomic resources will be useful for accelerating breeding of this underutilized grain crop and for fundamental insights into polyploid genome evolution.
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Affiliation(s)
- Robert VanBuren
- Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA.
- Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA.
| | - Ching Man Wai
- Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA
- Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA
| | - Xuewen Wang
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
| | - Jeremy Pardo
- Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA
- Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Alan E Yocca
- Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Hao Wang
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
| | | | - Guomin Han
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
| | - Douglas Bryant
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | - Patrick P Edger
- Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA
| | - Joachim Messing
- Waksman Institute of Microbiology, Rutgers University, Springfield, USA
| | - Mark E Sorrells
- Department of Plant Breeding and Genetics, Cornell University, Ithaca, NY, USA
| | - Todd C Mockler
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
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17
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Lee H, Chawla HS, Obermeier C, Dreyer F, Abbadi A, Snowdon R. Chromosome-Scale Assembly of Winter Oilseed Rape Brassica napus. FRONTIERS IN PLANT SCIENCE 2020; 11:496. [PMID: 32411167 PMCID: PMC7202327 DOI: 10.3389/fpls.2020.00496] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/01/2020] [Indexed: 05/19/2023]
Abstract
Rapeseed (Brassica napus), the second most important oilseed crop globally, originated from an interspecific hybridization between B. rapa and B. oleracea. After this genome collision, B. napus underwent extensive genome restructuring, via homoeologous chromosome exchanges, resulting in widespread segmental deletions and duplications. Illicit pairing among genetically similar homoeologous chromosomes during meiosis is common in recent allopolyploids like B. napus, and post-polyploidization restructuring compounds the difficulties of assembling a complex polyploid plant genome. Specifically, genomic rearrangements between highly similar chromosomes are challenging to detect due to the limitation of sequencing read length and ambiguous alignment of reads. Recent advances in long read sequencing technologies provide promising new opportunities to unravel the genome complexities of B. napus by encompassing breakpoints of genomic rearrangements with high specificity. Moreover, recent evidence revealed ongoing genomic exchanges in natural B. napus, highlighting the need for multiple reference genomes to capture structural variants between accessions. Here we report the first long-read genome assembly of a winter B. napus cultivar. We sequenced the German winter oilseed rape accession 'Express 617' using 54.5x of long reads. Short reads, linked reads, optical map data and high-density genetic maps were used to further correct and scaffold the assembly to form pseudochromosomes. The assembled Express 617 genome provides another valuable resource for Brassica genomics in understanding the genetic consequences of polyploidization, crop domestication, and breeding of recently-formed crop species.
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Affiliation(s)
- HueyTyng Lee
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
| | - Harmeet Singh Chawla
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
| | - Christian Obermeier
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
| | | | | | - Rod Snowdon
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
- *Correspondence: Rod Snowdon,
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18
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Lee H, Chawla HS, Obermeier C, Dreyer F, Abbadi A, Snowdon R. Chromosome-Scale Assembly of Winter Oilseed Rape Brassica napus. FRONTIERS IN PLANT SCIENCE 2020; 11:496. [PMID: 32411167 DOI: 10.3389/fpls.2020.00496/full] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/01/2020] [Indexed: 05/21/2023]
Abstract
Rapeseed (Brassica napus), the second most important oilseed crop globally, originated from an interspecific hybridization between B. rapa and B. oleracea. After this genome collision, B. napus underwent extensive genome restructuring, via homoeologous chromosome exchanges, resulting in widespread segmental deletions and duplications. Illicit pairing among genetically similar homoeologous chromosomes during meiosis is common in recent allopolyploids like B. napus, and post-polyploidization restructuring compounds the difficulties of assembling a complex polyploid plant genome. Specifically, genomic rearrangements between highly similar chromosomes are challenging to detect due to the limitation of sequencing read length and ambiguous alignment of reads. Recent advances in long read sequencing technologies provide promising new opportunities to unravel the genome complexities of B. napus by encompassing breakpoints of genomic rearrangements with high specificity. Moreover, recent evidence revealed ongoing genomic exchanges in natural B. napus, highlighting the need for multiple reference genomes to capture structural variants between accessions. Here we report the first long-read genome assembly of a winter B. napus cultivar. We sequenced the German winter oilseed rape accession 'Express 617' using 54.5x of long reads. Short reads, linked reads, optical map data and high-density genetic maps were used to further correct and scaffold the assembly to form pseudochromosomes. The assembled Express 617 genome provides another valuable resource for Brassica genomics in understanding the genetic consequences of polyploidization, crop domestication, and breeding of recently-formed crop species.
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Affiliation(s)
- HueyTyng Lee
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
| | - Harmeet Singh Chawla
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
| | - Christian Obermeier
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
| | | | | | - Rod Snowdon
- Department of Plant Breeding, Justus Liebig University Giessen, Giessen, Germany
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19
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Kryvokhyzha D, Milesi P, Duan T, Orsucci M, Wright SI, Glémin S, Lascoux M. Towards the new normal: Transcriptomic convergence and genomic legacy of the two subgenomes of an allopolyploid weed (Capsella bursa-pastoris). PLoS Genet 2019; 15:e1008131. [PMID: 31083657 PMCID: PMC6532933 DOI: 10.1371/journal.pgen.1008131] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 05/23/2019] [Accepted: 04/11/2019] [Indexed: 02/07/2023] Open
Abstract
Allopolyploidy has played a major role in plant evolution but its impact on genome diversity and expression patterns remains to be understood. Some studies found important genomic and transcriptomic changes in allopolyploids, whereas others detected a strong parental legacy and more subtle changes. The allotetraploid C. bursa-pastoris originated around 100,000 years ago and one could expect the genetic polymorphism of the two subgenomes to follow similar trajectories and their transcriptomes to start functioning together. To test this hypothesis, we sequenced the genomes and the transcriptomes (three tissues) of allotetraploid C. bursa-pastoris and its parental species, the outcrossing C. grandiflora and the self-fertilizing C. orientalis. Comparison of the divergence in expression between subgenomes, on the one hand, and divergence in expression between the parental species, on the other hand, indicated a strong parental legacy with a majority of genes exhibiting a conserved pattern and cis-regulation. However, a large proportion of the genes that were differentially expressed between the two subgenomes, were also under trans-regulation reflecting the establishment of a new regulatory pattern. Parental dominance varied among tissues: expression in flowers was closer to that of C. orientalis and expression in root and leaf to that of C. grandiflora. Since deleterious mutations accumulated preferentially on the C. orientalis subgenome, the bias in expression towards C. orientalis observed in flowers indicates that expression changes could be adaptive and related to the selfing syndrome, while biases in the roots and leaves towards the C. grandiflora subgenome may be reflective of the differential genetic load. Most plant species have a polyploid at some stage of their ancestry. Polyploidy, genome doubling through either multiple copies of a single species or through genomes of different species coming into the same nucleus, is therefore a crucial step in plant evolution. Understanding its impact on basic biological functions is thus a matter of interest. Shepherd’s purse (Capsella bursa-pastoris) is a major weed that appeared about 100,000 years ago through hybridization of two diploid species of the same genus. In the present project, we measured genetic diversity and analyzed gene expression patterns in flowers, roots, and leaves of C. bursa-pastoris individuals as well as in its two parental species, the outcrossing C. grandiflora and the self-fertilizing C. orientalis. Our data shows that, after 100,000 generations of evolution, the origin of the two subgenomes can still be seen: the genome inherited from C. grandiflora still differs from the one inherited from self-fertilizing C. orientalis. However, there are also signs that the two genomes have started to work together and are jointly regulated, and the way expression pattern varied across the three tissues indicates that the evolution of gene expression was adaptive.
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Affiliation(s)
- Dmytro Kryvokhyzha
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Pascal Milesi
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Tianlin Duan
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Marion Orsucci
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Stephen I. Wright
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Sylvain Glémin
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
- CNRS, Univ. Rennes, ECOBIO [(Ecosystèmes, biodiversité, évolution)] - UMR 6553, Rennes, France
| | - Martin Lascoux
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
- * E-mail:
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20
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Matos I, Machado MP, Schartl M, Coelho MM. Allele-specific expression variation at different ploidy levels in Squalius alburnoides. Sci Rep 2019; 9:3688. [PMID: 30842567 PMCID: PMC6403402 DOI: 10.1038/s41598-019-40210-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 02/07/2019] [Indexed: 11/09/2022] Open
Abstract
Allopolyploid plants are long known to be subject to a homoeolog expression bias of varying degree. The same phenomenon was only much later suspected to occur also in animals based on studies of single selected genes in an allopolyploid vertebrate, the Iberian fish Squalius alburnoides. Consequently, this species became a good model for understanding the evolution of gene expression regulation in polyploid vertebrates. Here, we analyzed for the first time genome-wide allele-specific expression data from diploid and triploid hybrids of S. alburnoides and compared homoeolog expression profiles of adult livers and of juveniles. Co-expression of alleles from both parental genomic types was observed for the majority of genes, but with marked homoeolog expression bias, suggesting homoeolog specific reshaping of expression level patterns in hybrids. Complete silencing of one allele was also observed irrespective of ploidy level, but not transcriptome wide as previously speculated. Instead, it was found only in a restricted number of genes, particularly ones with functions related to mitochondria and ribosomes. This leads us to hypothesize that allelic silencing may be a way to overcome intergenomic gene expression interaction conflicts, and that homoeolog expression bias may be an important mechanism in the achievement of sustainable genomic interactions, mandatory to the success of allopolyploid systems, as in S. alburnoides.
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Affiliation(s)
- Isa Matos
- Faculdade de Ciências, cE3c- Centro de Ecologia, Evolução e Alterações Ambientais, Departamento de Biologia Animal, Universidade de Lisboa Campo Grande, 1749-016, Lisboa, Portugal.,University of Würzburg, Biozentrum, Physiological Chemistry, Am Hubland, Würzburg, Germany
| | - Miguel P Machado
- Faculdade de Ciências, cE3c- Centro de Ecologia, Evolução e Alterações Ambientais, Departamento de Biologia Animal, Universidade de Lisboa Campo Grande, 1749-016, Lisboa, Portugal.,University of Würzburg, Biozentrum, Physiological Chemistry, Am Hubland, Würzburg, Germany.,Instituto de Microbiologia, Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Manfred Schartl
- University of Würzburg, Biozentrum, Physiological Chemistry, Am Hubland, Würzburg, Germany. .,Comprehensive Cancer Center, University Clinic Würzburg, Josef Schneider Straße 6, 97074, Würzburg, Germany. .,Hagler Institute for Advanced Study and Department of Biology, Texas A&M University, College Station, USA.
| | - Maria Manuela Coelho
- Faculdade de Ciências, cE3c- Centro de Ecologia, Evolução e Alterações Ambientais, Departamento de Biologia Animal, Universidade de Lisboa Campo Grande, 1749-016, Lisboa, Portugal
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21
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Evolution and Expression Divergence of the CYP78A Subfamily Genes in Soybean. Genes (Basel) 2018; 9:genes9120611. [PMID: 30544641 PMCID: PMC6316016 DOI: 10.3390/genes9120611] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 11/23/2018] [Accepted: 11/27/2018] [Indexed: 11/16/2022] Open
Abstract
Gene expression divergence is an important evolutionary driving force for the retention of duplicate genes. In this study, we identified three CYP78A subfamily genes in soybean, GmCYP78A70, GmCYP78A57 and GmCYP78A72, which experienced different duplication events. GmCYP78A70 was mainly expressed in leaf tissue and the vegetative phase, whereas GmCYP78A57 was mainly expressed in floral tissue and seed, i.e., the reproductive phase. Expression of GmCYP78A72 could be detected in all the tissues and phases mentioned above. The expression levels of GmCYP78A70 and GmCYP78A57 in different soybean cultivars showed positive correlations with leaf size and 100-seed weight, respectively. The population genetics analysis indicated that the three genes had experienced different selective pressures during domestication and improved breeding of soybean. Deciphering the function of this subfamily of genes may well prove useful to breeders for improving soybean’s agronomic traits.
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22
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Zhao L, Han L, Xiao C, Lin X, Xu C, Yang C. Rapid and pervasive development- and tissue-specific homeolog expression partitioning in newly formed inter-subspecific rice segmental allotetraploids. BMC Genomics 2018; 19:756. [PMID: 30340512 PMCID: PMC6194744 DOI: 10.1186/s12864-018-5150-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Accepted: 10/08/2018] [Indexed: 11/10/2022] Open
Abstract
Background In diverse plant taxa, whole-genome duplication (WGD) events are major sources of phenotypic novelty. Studies of gene expression in synthetic polyploids have shown immediate expression and functional partitioning of duplicated genes among different tissues. Many studies of the tissue-specific homeolog expression partitioning have focused on allopolyploids that have very different parental genomes, while few studies have focused on autopolyploids or allopolyploids that have similar parental genomes. Results In this study, we used a set of reciprocal F1 hybrids and synthetic tetraploids constructed from subspecies (japonica and indica) of Asian rice (Oryza sativa L.) as a model to gain insights into the expression partitioning of homeologs among tissues in a developmental context. We assayed the tissue-specific silencing (TSS) of the parental homeologs of 30 key genes in the hybrids and tetraploids relative to the in vitro “hybrids” (parental mixes) using Sequenom MassARRAY. We found that the parental mix and synthetic tetraploids had higher frequencies of homeolog TSS than the F1, revealing an instantaneous role of WGD on homeolog expression partitioning. Conclusions Our observations contradicted those of previous studies in which newly formed allopolyploids had a low TSS frequency, similar to that of F1 hybrids, suggesting that the impact of WGD on homeolog expression requires a longer time to manifest. In addition, we found that the TSS frequency in the tetraploids varied at different growth stages and that roots had a much higher frequency of TSS than leaves, which indicated that developmental and metabolic traits may influence the expression states of duplicated genes in newly formed plant polyploids. Electronic supplementary material The online version of this article (10.1186/s12864-018-5150-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Long Zhao
- Key laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Lei Han
- Key laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Chaoxia Xiao
- Key laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Xiuyun Lin
- Key laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Chunming Xu
- Key laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Chunwu Yang
- Key laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China.
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23
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A Robust Methodology for Assessing Differential Homeolog Contributions to the Transcriptomes of Allopolyploids. Genetics 2018; 210:883-894. [PMID: 30213855 DOI: 10.1534/genetics.118.301564] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 09/07/2018] [Indexed: 12/18/2022] Open
Abstract
Polyploidy has played a pivotal and recurring role in angiosperm evolution. Allotetraploids arise from hybridization between species and possess duplicated gene copies (homeologs) that serve redundant roles immediately after polyploidization. Although polyploidization is a major contributor to plant evolution, it remains poorly understood. We describe an analytical approach for assessing homeolog-specific expression that begins with de novo assembly of parental transcriptomes and effectively (i) reduces redundancy in de novo assemblies, (ii) identifies putative orthologs, (iii) isolates common regions between orthologs, and (iv) assesses homeolog-specific expression using a robust Bayesian Poisson-Gamma model to account for sequence bias when mapping polyploid reads back to parental references. Using this novel methodology, we examine differential homeolog contributions to the transcriptome in the recently formed allopolyploids Tragopogon mirus and T. miscellus (Compositae). Notably, we assess a larger Tragopogon gene set than previous studies of this system. Using carefully identified orthologous regions and filtering biased orthologs, we find in both allopolyploids largely balanced expression with no strong parental bias. These new methods can be used to examine homeolog expression in any tetrapolyploid system without requiring a reference genome.
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24
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Shan S, Mavrodiev EV, Li R, Zhang Z, Hauser BA, Soltis PS, Soltis DE, Yang B. Application of CRISPR/Cas9 to Tragopogon (Asteraceae), an evolutionary model for the study of polyploidy. Mol Ecol Resour 2018; 18:1427-1443. [PMID: 30086204 DOI: 10.1111/1755-0998.12935] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/23/2018] [Accepted: 07/28/2018] [Indexed: 01/21/2023]
Abstract
Tragopogon (Asteraceae) is an excellent natural system for studies of recent polyploidy. Development of an efficient CRISPR/Cas9-based genome editing platform in Tragopogon will facilitate novel studies of the genetic consequences of polyploidy. Here, we report our initial results of developing CRISPR/Cas9 in Tragopogon. We have established a feasible tissue culture and transformation protocol for Tragopogon. Through protoplast transient assays, use of the TragCRISPR system (i.e. the CRISPR/Cas9 system adapted for Tragopogon) was capable of introducing site-specific mutations in Tragopogon protoplasts. Agrobacterium-mediated transformation with Cas9-sgRNA constructs targeting the phytoene desaturase gene (TraPDS) was implemented in this model polyploid system. Sequencing of PCR amplicons from the target regions indicated simultaneous mutations of two alleles and four alleles of TraPDS in albino shoots from Tragopogon porrifolius (2x) and Tragopogon mirus (4x), respectively. The average proportions of successfully transformed calli with the albino phenotype were 87% and 78% in the diploid and polyploid, respectively. This appears to be the first demonstration of CRISPR/Cas9-based genome editing in any naturally formed neopolyploid system. Although a more efficient tissue culture system should be developed in Tragopogon, application of a robust CRISPR/Cas9 system will permit unique studies of biased fractionation, the gene-balance hypothesis and cytonuclear interactions in polyploids. In addition, the CRISPR/Cas9 platform enables investigations of those genes involved in phenotypic changes in polyploids and will also facilitate novel functional biology studies in Asteraceae. Our workflow provides a guide for applying CRISPR/Cas9 to other nongenetic model plant systems.
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Affiliation(s)
- Shengchen Shan
- Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, Florida.,Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa.,Florida Museum of Natural History, University of Florida, Gainesville, Florida
| | - Evgeny V Mavrodiev
- Florida Museum of Natural History, University of Florida, Gainesville, Florida
| | - Riqing Li
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
| | - Zhengzhi Zhang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
| | - Bernard A Hauser
- Department of Biology, University of Florida, Gainesville, Florida
| | - Pamela S Soltis
- Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, Florida.,Florida Museum of Natural History, University of Florida, Gainesville, Florida.,Biodiversity Institute, University of Florida, Gainesville, Florida
| | - Douglas E Soltis
- Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, Florida.,Florida Museum of Natural History, University of Florida, Gainesville, Florida.,Department of Biology, University of Florida, Gainesville, Florida.,Biodiversity Institute, University of Florida, Gainesville, Florida
| | - Bing Yang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
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25
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Ramírez-González RH, Borrill P, Lang D, Harrington SA, Brinton J, Venturini L, Davey M, Jacobs J, van Ex F, Pasha A, Khedikar Y, Robinson SJ, Cory AT, Florio T, Concia L, Juery C, Schoonbeek H, Steuernagel B, Xiang D, Ridout CJ, Chalhoub B, Mayer KFX, Benhamed M, Latrasse D, Bendahmane A, Wulff BBH, Appels R, Tiwari V, Datla R, Choulet F, Pozniak CJ, Provart NJ, Sharpe AG, Paux E, Spannagl M, Bräutigam A, Uauy C. The transcriptional landscape of polyploid wheat. Science 2018; 361:eaar6089. [PMID: 30115782 DOI: 10.1126/science.aar6089] [Citation(s) in RCA: 530] [Impact Index Per Article: 88.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 07/11/2018] [Indexed: 12/14/2022]
Abstract
The coordinated expression of highly related homoeologous genes in polyploid species underlies the phenotypes of many of the world's major crops. Here we combine extensive gene expression datasets to produce a comprehensive, genome-wide analysis of homoeolog expression patterns in hexaploid bread wheat. Bias in homoeolog expression varies between tissues, with ~30% of wheat homoeologs showing nonbalanced expression. We found expression asymmetries along wheat chromosomes, with homoeologs showing the largest inter-tissue, inter-cultivar, and coding sequence variation, most often located in high-recombination distal ends of chromosomes. These transcriptionally dynamic genes potentially represent the first steps toward neo- or subfunctionalization of wheat homoeologs. Coexpression networks reveal extensive coordination of homoeologs throughout development and, alongside a detailed expression atlas, provide a framework to target candidate genes underpinning agronomic traits in wheat.
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26
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Cheng F, Wu J, Cai X, Liang J, Freeling M, Wang X. Gene retention, fractionation and subgenome differences in polyploid plants. NATURE PLANTS 2018; 4:258-268. [PMID: 29725103 DOI: 10.1038/s41477-018-0136-7] [Citation(s) in RCA: 181] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 03/20/2018] [Indexed: 05/22/2023]
Abstract
All natural plant species are evolved from ancient polyploids. Polyloidization plays an important role in plant genome evolution, species divergence and crop domestication. We review how the pattern of polyploidy within the plant phylogenetic tree has engendered hypotheses involving mass extinctions, lag-times following polyploidy, and epochs of asexuality. Polyploidization has happened repeatedly in plant evolution and, we conclude, is important for crop domestication. Once duplicated, the effect of purifying selection on any one duplicated gene is relaxed, permitting duplicate gene and regulatory element loss (fractionation). We review the general topic of fractionation, and how some gene categories are retained more than others. Several explanations, including neofunctionalization, subfunctionalization and gene product dosage balance, have been shown to influence gene content over time. For allopolyploids, genetic differences between parental lines immediately manifest as subgenome dominance in the wide-hybrid, and persist and propagate for tens of millions of years. While epigenetic modifications are certainly involved in genome dominance, it has been difficult to determine which came first, the chromatin marks being measured or gene expression. Data support the conclusion that genome dominance and heterosis are antagonistic and mechanically entangled; both happen immediately in the synthetic wide-cross hybrid. Also operating in this hybrid are mechanisms of 'paralogue interference'. We present a foundation model to explain gene expression and vigour in a wide hybrid/new allotetraploid. This Review concludes that some mechanisms operate immediately at the wide-hybrid, and other mechanisms begin their operations later. Direct interaction of new paralogous genes, as measured using high-resolution chromatin conformation capture, should inform future research and single cell transcriptome sequencing should help achieve specificity while studying gene sub- and neo-functionalization.
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Affiliation(s)
- Feng Cheng
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing, China
| | - Jian Wu
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing, China
| | - Xu Cai
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing, China
| | - Jianli Liang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing, China
| | - Michael Freeling
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.
| | - Xiaowu Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing, China.
- Shandong Provincial Key Laboratory of Protected Vegetable Molecular Breeding, Shandong Shouguang Vegetable Seed Industry Group Co. Ltd., Shandong Province, China.
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27
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Jighly A, Joukhadar R, Singh S, Ogbonnaya FC. Decomposing Additive Genetic Variance Revealed Novel Insights into Trait Evolution in Synthetic Hexaploid Wheat. Front Genet 2018; 9:27. [PMID: 29467793 PMCID: PMC5807918 DOI: 10.3389/fgene.2018.00027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 01/22/2018] [Indexed: 11/13/2022] Open
Abstract
Whole genome duplication (WGD) is an evolutionary phenomenon, which causes significant changes to genomic structure and trait architecture. In recent years, a number of studies decomposed the additive genetic variance explained by different sets of variants. However, they investigated diploid populations only and none of the studies examined any polyploid organism. In this research, we extended the application of this approach to polyploids, to differentiate the additive variance explained by the three subgenomes and seven sets of homoeologous chromosomes in synthetic allohexaploid wheat (SHW) to gain a better understanding of trait evolution after WGD. Our SHW population was generated by crossing improved durum parents (Triticum turgidum; 2n = 4x = 28, AABB subgenomes) with the progenitor species Aegilops tauschii (syn Ae. squarrosa, T. tauschii; 2n = 2x = 14, DD subgenome). The population was phenotyped for 10 fungal/nematode resistance traits as well as two abiotic stresses. We showed that the wild D subgenome dominated the additive effect and this dominance affected the A more than the B subgenome. We provide evidence that this dominance was not inflated by population structure, relatedness among individuals or by longer linkage disequilibrium blocks observed in the D subgenome within the population used for this study. The cumulative size of the three homoeologs of the seven chromosomal groups showed a weak but significant positive correlation with their cumulative explained additive variance. Furthermore, an average of 69% for each chromosomal group's cumulative additive variance came from one homoeolog that had the highest explained variance within the group across all 12 traits. We hypothesize that structural and functional changes during diploidization may explain chromosomal group relations as allopolyploids keep balanced dosage for many genes. Our results contribute to a better understanding of trait evolution mechanisms in polyploidy, which will facilitate the effective utilization of wheat wild relatives in breeding.
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Affiliation(s)
- Abdulqader Jighly
- Agriculture Victoria, Agriculture Research Division, AgriBio, Centre for AgriBiosciences, Bundoora, VIC, Australia.,School of Applied Systems Biology, La Trobe University, Bundoora, VIC, Australia
| | - Reem Joukhadar
- Agriculture Victoria, Agriculture Research Division, AgriBio, Centre for AgriBiosciences, Bundoora, VIC, Australia.,Department of Animal, Plant and Soil Sciences, La Trobe University, Bundoora, VIC, Australia
| | - Sukhwinder Singh
- International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
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Zhao C, Li H, Zhang W, Wang H, Xu A, Tian J, Zou J, Taylor DC, Zhang M. BnDGAT1s Function Similarly in Oil Deposition and Are Expressed with Uniform Patterns in Tissues of Brassica napus. FRONTIERS IN PLANT SCIENCE 2017; 8:2205. [PMID: 29312429 PMCID: PMC5744481 DOI: 10.3389/fpls.2017.02205] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 12/14/2017] [Indexed: 05/03/2023]
Abstract
As an allotetraploid oilcrop, Brassica napus contains four duplicated Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) genes, which catalyze one of the rate-limiting steps in triacylglycerol (TAG) biosynthesis in plants. While all four BnDGAT1s have been expressed functionally in yeast, their expression patterns in different germplasms and tissues and also consequent contribution to seed oil accumulation in planta remain to be elucidated. In this study, the coding regions of the four BnDGAT1s were expressed in an Arabidopsis dgat1 mutant. All four BnDGAT1s showed similar effects on oil content and fatty acid composition, a result which is different from that observed in previous studies of their expression in yeast. Expression patterns of BnDGAT1s were analyzed in developing seeds of 34 B. napus inbred lines and in different tissues of 14 lines. Different expression patterns were observed for the four BnDGAT1s, which suggests that they express independently or randomly in different germplasm sources. Higher expression of BnDGAT1s was correlated with higher seed oil content lines. Tissue-specific analyses showed that the BnDGAT1s were expressed in a uniform pattern in different tissues. Our results suggest that it is important to maintain expression of the four BnDGAT1s for maximum return on oil content.
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Affiliation(s)
- Cuizhu Zhao
- College of Agronomy, Northwest A&F University, Yangling, China
| | - Huan Li
- College of Agronomy, Northwest A&F University, Yangling, China
| | | | - Hailan Wang
- College of Agronomy, Northwest A&F University, Yangling, China
| | - Aixia Xu
- College of Agronomy, Northwest A&F University, Yangling, China
| | | | - Jitao Zou
- National Research Council of Canada, Saskatoon, SK, Canada
| | | | - Meng Zhang
- College of Agronomy, Northwest A&F University, Yangling, China
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29
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Spoelhof JP, Chester M, Rodriguez R, Geraci B, Heo K, Mavrodiev E, Soltis PS, Soltis DE. Karyotypic variation and pollen stainability in resynthesized allopolyploids Tragopogon miscellus and T. mirus. AMERICAN JOURNAL OF BOTANY 2017; 104:1484-1492. [PMID: 29885228 DOI: 10.3732/ajb.1700180] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 09/08/2017] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Polyploidy has extensively shaped the evolution of plants, but the early stages of polyploidy are still poorly understood. The neoallopolyploid species Tragopogon mirus and T. miscellus are both characterized by widespread karyotypic variation, including frequent aneuploidy and intergenomic translocations. Our study illuminates the origins and early impacts of this variation by addressing two questions: How quickly does karyotypic variation accumulate in Tragopogon allopolyploids following whole-genome duplication (WGD), and how does the fertility of resynthesized Tragopogon allopolyploids evolve shortly after WGD? METHODS We used genomic in situ hybridization and lactophenol-cotton blue staining to estimate the karyotypic variation and pollen stainability, respectively, of resynthesized T. mirus and T. miscellus during the first five generations after WGD. KEY RESULTS Widespread karyotypic variation developed quickly in synthetics and resembled that of naturally occurring T. mirus and T. miscellus by generation S4 . Pollen stainability in resynthesized allopolyploids was consistently lower than that of natural T. mirus and T. miscellus, as well as their respective diploid progenitor species. Logistic regression showed that mean pollen stainability increased slightly over four generations in resynthesized T. mirus but remained at equivalent levels in T. miscellus. CONCLUSIONS Our results clarify some of the changes that occur in T. mirus and T. miscellus immediately following their origin, most notably the rapid onset of karyotypic variation within these species immediately following WGD.
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Affiliation(s)
- Jonathan P Spoelhof
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611, USA
- Department of Biology, University of Florida, Gainesville, Florida 32611, USA
| | - Michael Chester
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611, USA
- Department of Biology, University of Florida, Gainesville, Florida 32611, USA
- Royal Botanic Gardens, Kew, Natural Capital and Plant Health Department, Richmond, Surrey TW9 3DS, UK
| | - Roseana Rodriguez
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611, USA
- Department of Biology, University of Florida, Gainesville, Florida 32611, USA
| | - Blake Geraci
- Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611, USA
- Department of Biology, University of Florida, Gainesville, Florida 32611, USA
| | - Kweon Heo
- Kangwon National University, Department of Applied Plant Sciences, Chuncheon 24341, Korea
| | - Evgeny Mavrodiev
- Florida Museum of Natural History, 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 32610, USA
| | - 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 32610, USA
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30
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Sun Y, Wu Y, Yang C, Sun S, Lin X, Liu L, Xu C, Wendel JF, Gong L, Liu B. Segmental allotetraploidy generates extensive homoeologous expression rewiring and phenotypic diversity at the population level in rice. Mol Ecol 2017; 26:5451-5466. [PMID: 28802080 DOI: 10.1111/mec.14297] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 06/04/2017] [Accepted: 07/24/2017] [Indexed: 02/03/2023]
Abstract
Allopolyploidization, that is, concomitant merging and doubling of two or more divergent genomes in a common nucleus/cytoplasm, is known to instantly alter genomewide transcriptome dynamics, a phenomenon referred to as "transcriptomic shock." However, the immediate effects of transcriptomic alteration in generating phenotypic diversity at the population level remain underinvestigated. Here, we employed the MassARRAY-based Sequenom platform to assess and compare orthologous, allelic and homoeologous gene expression status in two tissues (leaf and root) of a set of randomly chosen individuals from populations of parental rice subspecies (indica and japonica), in vitro "hybrids" (parental mixes), reciprocal F1 hybrids and reciprocal tetraploids at the 5th-selfed generation (S5). We show that hybridization and whole genome duplication (WGD) have opposing effects on allelic and homoeologous expression in the F1 hybrids and tetraploids, respectively. Whereas hybridization exerts strong attenuating effects on allelic expression differences in diploid hybrids, WGD augments the intrinsic parental differences and generates extensive and variable homoeolog content which triggers diversification in expression patterning among the tetraploid plants. Coupled with the vast phenotypic diversity observed among the tetraploid individuals, our results provide experimental evidence in support of the notion that allopolyploidy catalyses rapid phenotypic diversification in higher plants. Our data further suggest that largely stochastic homoeolog content reshuffling rather than alteration in total expression level may be an important feature of evolution in young segmental allopolyploids, which underlies rapid expression diversity at the population level.
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Affiliation(s)
- Yue Sun
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Ying Wu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Chunwu Yang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Shuai Sun
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Xiuyun Lin
- Jilin Academy of Agriculture, Changchun, China
| | - Lixia Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Chunming Xu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Jonathan F Wendel
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Lei Gong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China.,Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
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31
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Mutti JS, Bhullar RK, Gill KS. Evolution of Gene Expression Balance Among Homeologs of Natural Polyploids. G3 (BETHESDA, MD.) 2017; 7:1225-1237. [PMID: 28193629 PMCID: PMC5386871 DOI: 10.1534/g3.116.038711] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 02/11/2017] [Indexed: 11/18/2022]
Abstract
Polyploidy is a major evolutionary process in eukaryotes, yet the expression balance of homeologs in natural polyploids is largely unknown. To study this expression balance, the expression patterns of 2180 structurally well-characterized genes of wheat were studied, of which 813 had the expected three copies and 375 had less than three. Copy numbers of the remaining 992 ranged from 4 to 14, including homeologs, orthologs, and paralogs. Of the genes with three structural copies corresponding to homeologs, 55% expressed from all three, 38% from two, and the remaining 7% expressed from only one of the three copies. Homeologs of 76-87% of the genes showed differential expression patterns in different tissues, thus have evolved different gene expression controls, possibly resulting in novel functions. Homeologs of 55% of the genes showed tissue-specific expression, with the largest percentage (14%) in the anthers and the smallest (7%) in the pistils. The highest number (1.72/3) of homeologs/gene expression was in the roots and the lowest (1.03/3) in the anthers. As the expression of homeologs changed with changes in structural copy number, about 30% of the genes showed dosage dependence. Chromosomal location also impacted expression pattern as a significantly higher proportion of genes in the proximal regions showed expression from all three copies compared to that present in the distal regions.
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Affiliation(s)
- Jasdeep S Mutti
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420
| | - Ramanjot K Bhullar
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420
| | - Kulvinder S Gill
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420
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32
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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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33
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Akagi T, Henry IM, Morimoto T, Tao R. Insights into the Prunus-Specific S-RNase-Based Self-Incompatibility System from a Genome-Wide Analysis of the Evolutionary Radiation of S Locus-Related F-box Genes. PLANT & CELL PHYSIOLOGY 2016; 57:1281-1294. [PMID: 27081098 DOI: 10.1093/pcp/pcw077] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/06/2016] [Indexed: 06/05/2023]
Abstract
Self-incompatibility (SI) is an important plant reproduction mechanism that facilitates the maintenance of genetic diversity within species. Three plant families, the Solanaceae, Rosaceae and Plantaginaceae, share an S-RNase-based gametophytic SI (GSI) system that involves a single S-RNase as the pistil S determinant and several F-box genes as pollen S determinants that act via non-self-recognition. Previous evidence has suggested a specific self-recognition mechanism in Prunus (Rosaceae), raising questions about the generality of the S-RNase-based GSI system. We investigated the evolution of the pollen S determinant by comparing the sequences of the Prunus S haplotype-specific F-box gene (SFB) with those of its orthologs in other angiosperm genomes. Our results indicate that the Prunus SFB does not cluster with the pollen S of other plants and diverged early after the establishment of the Eudicots. Our results further indicate multiple F-box gene duplication events, specifically in the Rosaceae family, and suggest that the Prunus SFB gene originated in a recent Prunus-specific gene duplication event. Transcriptomic and evolutionary analyses of the Prunus S paralogs are consistent with the establishment of a Prunus-specific SI system, and the possibility of subfunctionalization differentiating the newly generated SFB from the original pollen S determinant.
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Affiliation(s)
- Takashi Akagi
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502 Japan Department of Plant Biology and Genome Center, University of California Davis, Davis, CA 95616, USA
| | - Isabelle M Henry
- Department of Plant Biology and Genome Center, University of California Davis, Davis, CA 95616, USA
| | - Takuya Morimoto
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502 Japan
| | - Ryutaro Tao
- Laboratory of Pomology, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502 Japan
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34
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Alexander-Webber D, Abbott RJ, Chapman MA. Morphological Convergence Between an Allopolyploid and One of its Parental Species Correlates with Biased Gene Expression and DNA Loss. J Hered 2016; 107:445-54. [DOI: 10.1093/jhered/esw035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 05/20/2016] [Indexed: 11/14/2022] Open
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35
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Gallagher JP, Grover CE, Hu G, Wendel JF. Insights into the Ecology and Evolution of Polyploid Plants through Network Analysis. Mol Ecol 2016; 25:2644-60. [PMID: 27027619 DOI: 10.1111/mec.13626] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 03/09/2016] [Accepted: 03/22/2016] [Indexed: 12/18/2022]
Abstract
Polyploidy is a widespread phenomenon throughout eukaryotes, with important ecological and evolutionary consequences. Although genes operate as components of complex pathways and networks, polyploid changes in genes and gene expression have typically been evaluated as either individual genes or as a part of broad-scale analyses. Network analysis has been fruitful in associating genomic and other 'omic'-based changes with phenotype for many systems. In polyploid species, network analysis has the potential not only to facilitate a better understanding of the complex 'omic' underpinnings of phenotypic and ecological traits common to polyploidy, but also to provide novel insight into the interaction among duplicated genes and genomes. This adds perspective to the global patterns of expression (and other 'omic') change that accompany polyploidy and to the patterns of recruitment and/or loss of genes following polyploidization. While network analysis in polyploid species faces challenges common to other analyses of duplicated genomes, present technologies combined with thoughtful experimental design provide a powerful system to explore polyploid evolution. Here, we demonstrate the utility and potential of network analysis to questions pertaining to polyploidy with an example involving evolution of the transgressively superior cotton fibres found in polyploid Gossypium hirsutum. By combining network analysis with prior knowledge, we provide further insights into the role of profilins in fibre domestication and exemplify the potential for network analysis in polyploid species.
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Affiliation(s)
- Joseph P Gallagher
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, 50011, USA
| | - Corrinne E Grover
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, 50011, USA
| | - Guanjing Hu
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, 50011, USA
| | - Jonathan F Wendel
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, 50011, USA
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36
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Fulneček J, Matyášek R. The origin of exon 3 skipping of paternal GLOBOSA pre-mRNA in some Nicotiana tabacum lines correlates with a point mutation of the very last nucleotide of the exon. Mol Genet Genomics 2016; 291:801-18. [PMID: 26603606 DOI: 10.1007/s00438-015-1149-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 11/13/2015] [Indexed: 10/22/2022]
Abstract
In plants, genome duplication followed by genome diversification and selection is recognized as a major evolutionary process. Rapid epigenetic and genetic changes that affect the transcription of parental genes are frequently observed after polyploidization. The pattern of alternative splicing is also frequently altered, yet the related molecular processes remain largely unresolved. Here, we study the inheritance and expression of parental variants of three floral organ identity genes in allotetraploid tobacco. DEFICIENS and GLOBOSA are B-class genes, and AGAMOUS is a C-class gene. Parental variants of these genes were found to be maintained in the tobacco genome, and the respective mRNAs were present in flower buds in comparable amounts. However, among five tobacco cultivars, we identified two in which the majority of paternal GLOBOSA pre-mRNA transcripts undergo exon 3 skipping, producing an mRNA with a premature termination codon. At the DNA level, we identified a G-A transition at the very last position of exon 3 in both cultivars. Although alternative splicing resulted in a dramatic decrease in full-length paternal GLOBOSA mRNA, no phenotypic effect was observed. Our finding likely serves as an example of the initiation of homoeolog diversification in a relatively young polyploid genome.
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Affiliation(s)
- Jaroslav Fulneček
- Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-61265, Brno, Czech Republic.
| | - Roman Matyášek
- Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-61265, Brno, Czech Republic
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37
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Soltis DE, Misra BB, Shan S, Chen S, Soltis PS. Polyploidy and the proteome. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:896-907. [PMID: 26993527 DOI: 10.1016/j.bbapap.2016.03.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 03/06/2016] [Accepted: 03/11/2016] [Indexed: 12/23/2022]
Abstract
Although major advances have been made during the past 20 years in our understanding of the genetic and genomic consequences of polyploidy, our knowledge of polyploidy and the proteome is in its infancy. One of our goals is to stimulate additional study, particularly broad-scale proteomic analyses of polyploids and their progenitors. Although it may be too early to generalize regarding the extent to which transcriptomic data are predictive of the proteome of polyploids, it is clear that the proteome does not always reflect the transcriptome. Despite limited data, important observations on the proteomes of polyploids are emerging. In some cases, proteomic profiles show qualitatively and/or quantitatively non-additive patterns, and proteomic novelty has been observed. Allopolyploids generally combine the parental contributions, but there is evidence of parental dominance of one contributing genome in some allopolyploids. Autopolyploids are typically qualitatively identical to but quantitatively different from their parents. There is also evidence of parental legacy at the proteomic level. Proteomes clearly provide insights into the consequences of genomic merger and doubling beyond what is obtained from genomic and/or transcriptomic data. Translating proteomic changes in polyploids to differences in morphology and physiology remains the holy grail of polyploidy--this daunting task of linking genotype to proteome to phenotype should emerge as a focus of polyploidy research in the next decade. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.
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Affiliation(s)
- Douglas E Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA; Department of Biology, University of Florida, Gainesville, FL 32611, USA; Genetics Institute, University of Florida, Gainesville, FL 32608, USA; Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32610, USA.
| | - Biswapriya B Misra
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Shengchen Shan
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA; Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32610, USA
| | - Sixue Chen
- Department of Biology, University of Florida, Gainesville, FL 32611, USA; Genetics Institute, University of Florida, Gainesville, FL 32608, USA; Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32610, USA; Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL 32610, USA
| | - Pamela S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA; Genetics Institute, University of Florida, Gainesville, FL 32608, USA; Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32610, USA.
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38
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Zhu QH, Zhang J, Liu D, Stiller W, Liu D, Zhang Z, Llewellyn D, Wilson I. Integrated mapping and characterization of the gene underlying the okra leaf trait in Gossypium hirsutum L. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:763-74. [PMID: 26567355 PMCID: PMC4737076 DOI: 10.1093/jxb/erv494] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Diverse leaf morphology has been observed among accessions of Gossypium hirsutum, including okra leaf, which has advantages and disadvantages in cotton production. The okra leaf locus has been mapped to chromosome 15 of the Dt subgenome, but the underlying gene has yet to be identified. In this study, we used a combination of targeted association analysis, F2 population-based fine mapping, and comparative sequencing of orthologues to identify a candidate gene underlying the okra leaf trait in G. hirsutum. The okra leaf gene identified, GhOKRA, encoded a homeodomain leucine-zipper class I protein, whose closely related genes in several other plant species have been shown to be involved in regulating leaf morphology. The transcript levels of GhOKRA in shoot apices were positively correlated with the phenotypic expression of the okra leaf trait. Of the multiple sequence variations observed in the coding region among GrOKRA of Gossypium raimondii and GhOKRA-Dt of normal and okra/superokra leaf G. hirsutum accessions, a non-synonymous substitution near the N terminus and the variable protein sequences at the C terminus may be related to the leaf shape difference. Our results suggest that both transcription and protein activity of GhOKRA may be involved in regulating leaf shape. Furthermore, we found that non-reciprocal homoeologous recombination, or gene conversion, may have played a role in the origin of the okra leaf allele. Our results provided tools for further investigating and understanding the fundamental biological processes that are responsible for the cotton leaf shape variation and will help in the design of cotton plants with an ideal leaf shape for enhanced cotton production.
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Affiliation(s)
- Qian-Hao Zhu
- CSIRO Agriculture, Black Mountain Laboratories, ACT 2601, Australia
| | - Jian Zhang
- CSIRO Agriculture, Black Mountain Laboratories, ACT 2601, Australia College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, PR China
| | - Dexin Liu
- College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, PR China
| | - Warwick Stiller
- CSIRO Agriculture, Locked Bag 59, Narrabri NSW 2390, Australia
| | - Dajun Liu
- College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, PR China
| | - Zhengsheng Zhang
- College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, PR China
| | - Danny Llewellyn
- CSIRO Agriculture, Black Mountain Laboratories, ACT 2601, Australia
| | - Iain Wilson
- CSIRO Agriculture, Black Mountain Laboratories, ACT 2601, Australia
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Wang X, Zhang H, Li Y, Zhang Z, Li L, Liu B. Transcriptome asymmetry in synthetic and natural allotetraploid wheats, revealed by RNA-sequencing. THE NEW PHYTOLOGIST 2016; 209:1264-77. [PMID: 26436593 DOI: 10.1111/nph.13678] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 08/20/2015] [Indexed: 05/20/2023]
Abstract
Allopolyploidization has occurred frequently within the Triticum-Aegilops complex which provides a suitable system to investigate how allopolyploidization shapes the expression patterns of duplicated homeologs. We have conducted transcriptome-profiling of leaves and young inflorescences in wild and domesticated tetraploid wheats, Triticum turgidum ssp. dicoccoides (BBAA) and ssp. durum (BBAA), an extracted tetraploid (BBAA), and a synthetic tetraploid (S(l) S(l) AA) wheat together with its diploid parents, Aegilops longissima (S(l) S(l) ) and Triticum urartu (AA). The two diploid species showed tissue-specific differences in genome-wide ortholog expression, which plays an important role in transcriptome shock-mediated homeolog expression rewiring and hence transcriptome asymmetry in the synthetic tetraploid. Further changes of homeolog expression apparently occurred in natural tetraploid wheats, which led to novel transcriptome asymmetry between the two subgenomes. In particular, our results showed that extremely biased homeolog expression can occur rapidly upon the allotetraploidzation and this trend is further enhanced in the course of domestication and evolution of polyploid wheats. Our results suggest that allopolyploidization is accompanied by distinct phases of homeolog expression changes, with parental legacy playing major roles in the immediate rewiring of homeolog expression upon allopolyploidization, while evolution and domestication under allotetraploidy drive further homeolog-expression changes toward re-established subgenome expression asymmetry.
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Affiliation(s)
- Xutong Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Huakun Zhang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Yaling Li
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Zhibin Zhang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
| | - Linfeng Li
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
- Department of Biology, Washington University in St Louis, St Louis, MO, 63130, USA
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, 130024, China
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40
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Sequence and gene expression evolution of paralogous genes in willows. Sci Rep 2015; 5:18662. [PMID: 26689951 PMCID: PMC4687058 DOI: 10.1038/srep18662] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 11/23/2015] [Indexed: 01/15/2023] Open
Abstract
Whole genome duplications (WGD) have had strong impacts on species diversification by triggering evolutionary novelties, however, relatively little is known about the balance between gene loss and forces involved in the retention of duplicated genes originating from a WGD. We analyzed putative Salicoid duplicates in willows, originating from the Salicoid WGD, which took place more than 45 Mya. Contigs were constructed by de novo assembly of RNA-seq data derived from leaves and roots from two genotypes. Among the 48,508 contigs, 3,778 pairs were, based on fourfold synonymous third-codon transversion rates and syntenic positions, predicted to be Salicoid duplicates. Both copies were in most cases expressed in both tissues and 74% were significantly differentially expressed. Mean Ka/Ks was 0.23, suggesting that the Salicoid duplicates are evolving by purifying selection. Gene Ontology enrichment analyses showed that functions related to DNA- and nucleic acid binding were over-represented among the non-differentially expressed Salicoid duplicates, while functions related to biosynthesis and metabolism were over-represented among the differentially expressed Salicoid duplicates. We propose that the differentially expressed Salicoid duplicates are regulatory neo- and/or subfunctionalized, while the non-differentially expressed are dose sensitive, hence, functionally conserved. Multiple evolutionary processes, thus drive the retention of Salicoid duplicates in willows.
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41
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Polyploidy and genome evolution in plants. Curr Opin Genet Dev 2015; 35:119-25. [PMID: 26656231 DOI: 10.1016/j.gde.2015.11.003] [Citation(s) in RCA: 358] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 11/10/2015] [Indexed: 11/20/2022]
Abstract
Plant genomes vary in size and complexity, fueled in part by processes of whole-genome duplication (WGD; polyploidy) and subsequent genome evolution. Despite repeated episodes of WGD throughout the evolutionary history of angiosperms in particular, the genomes are not uniformly large, and even plants with very small genomes carry the signatures of ancient duplication events. The processes governing the evolution of plant genomes following these ancient events are largely unknown. Here, we consider mechanisms of diploidization, evidence of genome reorganization in recently formed polyploid species, and macroevolutionary patterns of WGD in plant genomes and propose that the ongoing genomic changes observed in recent polyploids may illustrate the diploidization processes that result in ancient signatures of WGD over geological timescales.
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42
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Gene-expression novelty in allopolyploid cotton: a proteomic perspective. Genetics 2015; 200:91-104. [PMID: 25735302 DOI: 10.1534/genetics.115.174367] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/28/2015] [Indexed: 01/20/2023] Open
Abstract
Allopolyploidization is accompanied by changes in gene expression that are thought to contribute to phenotypic diversification. Here we describe global changes in the single-celled cotton fiber proteome of two natural allopolyploid species (Gossypium hirsutum and G. barbadense) and living models of their diploid parents using two different proteomic approaches. In total, 1323 two-dimensional gel electrophoresis spots and 1652 identified proteins by isobaric tags for relative and absolute quantitation were quantitatively profiled during fiber elongation. Between allopolyploids and their diploid A- and D-genome progenitors, amounts of differential expression ranged from 4.4 to 12.8%. Over 80% of the allopolyploid proteome was additively expressed with respect to progenitor diploids. Interestingly, the fiber proteome of G. hirsutum resembles the parental A-genome more closely, where long, spinable fiber first evolved, than does the fiber proteome of G. barbadense. More protein expression patterns were A-dominant than D-dominant in G. hirsutum, but in G. barbadense, the direction of expression-level dominance switched from the D-genome to the A-genome during fiber development. Comparison of developmental changes between the two allopolyploid species revealed a high level of proteomic differentiation despite their shared ancestry, relatively recent evolutionary divergence, and similar gross morphology. These results suggest that the two allopolyploid species have achieved superficially similar modern fiber phenotypes through different evolutionary routes at the proteome level. We also detected homeolog-specific expression for 1001 proteins and present a novel approach to infer the relationship between homeolog-specific and duplicate expression patterns. Our study provides a proteomic perspective on understanding evolutionary consequences of allopolyploidization, showing how protein expression has been altered by polyploidization and subsequently has diversified among species.
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Chester M, Riley RK, Soltis PS, Soltis DE. Patterns of chromosomal variation in natural populations of the neoallotetraploid Tragopogon mirus (Asteraceae). Heredity (Edinb) 2015; 114:309-17. [PMID: 25370212 PMCID: PMC4815575 DOI: 10.1038/hdy.2014.101] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 09/04/2014] [Accepted: 09/09/2014] [Indexed: 12/16/2022] Open
Abstract
Cytological studies have shown many newly formed allopolyploids (neoallopolyploids) exhibit chromosomal variation as a result of meiotic irregularities, but few naturally occurring neoallopolyploids have been examined. Little is known about how long chromosomal variation may persist and how it might influence the establishment and evolution of allopolyploids in nature. In this study we assess chromosomal composition in a natural neoallotetraploid, Tragopogon mirus, and compare it with T. miscellus, which is an allotetraploid of similar age (~40 generations old). We also assess whether parental gene losses in T. mirus correlate with entire or partial chromosome losses. Of 37 T. mirus individuals that were karyotyped, 23 (62%) were chromosomally additive of the parents, whereas the remaining 14 individuals (38%) had aneuploid compositions. The proportion of additive versus aneuploid individuals differed from that found previously in T. miscellus, in which aneuploidy was more common (69%; Fisher's exact test, P=0.0033). Deviations from parental chromosome additivity within T. mirus individuals also did not reach the levels observed in T. miscellus, but similar compensated changes were observed. The loss of T. dubius-derived genes in two T. mirus individuals did not correlate with any chromosomal changes, indicating a role for smaller-scale genetic alterations. Overall, these data for T. mirus provide a second example of prolonged chromosomal instability in natural neoallopolyploid populations.
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Affiliation(s)
- M Chester
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - R K Riley
- Department of Biology, University of Florida, Gainesville, FL, USA
- Department of Plant Biology, University of Georgia, Athens, GA, USA
| | - P S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL, USA
| | - D E Soltis
- Department of Biology, University of Florida, Gainesville, FL, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL, USA
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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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Renny-Byfield S, Gong L, Gallagher JP, Wendel JF. Persistence of subgenomes in paleopolyploid cotton after 60 my of evolution. Mol Biol Evol 2015; 32:1063-71. [PMID: 25573906 DOI: 10.1093/molbev/msv001] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The importance of whole-genome multiplication (WGM) in plant evolution has long been recognized. In flowering plants, WGM is both ubiquitous and in many lineages cyclical, each round followed by substantial gene loss (fractionation). This process may be biased with respect to duplicated chromosomes, often with overexpression of genes in less fractionated relative to more fractionated regions. This bias is hypothesized to arise through downregulation of gene expression through silencing of local transposable elements (TEs). We assess differences in gene expression between duplicated regions of the paleopolyploid cotton genome and demonstrate that the rate of fractionation is negatively correlated with gene expression. We examine recent hypotheses regarding the source of fractionation bias and show that TE-mediated, positional downregulation is absent in the modern cotton genome, seemingly excluding this phenomenon as the primary driver of biased gene loss. Nevertheless, the paleo subgenomes of diploid cotton are still distinguishable with respect to TE content, targeting of 24-nt-small interfering RNAs and GC content, despite approximately 60 My of evolution. We propose that repeat content per se and differential recombination rates may drive biased fractionation following WGM. These data highlight the likely importance of ancient genomic fractionation biases in shaping modern crop genomes.
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Affiliation(s)
- Simon Renny-Byfield
- Department of Ecology, Evolution and Organismal Biology, Iowa State University Department of Ecology, Evolution and Organismal Biology, Iowa State University
| | - Lei Gong
- Department of Ecology, Evolution and Organismal Biology, Iowa State University
| | - Joseph P Gallagher
- Department of Ecology, Evolution and Organismal Biology, Iowa State University
| | - Jonathan F Wendel
- Department of Ecology, Evolution and Organismal Biology, Iowa State University
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Singh VK, Jain M. Genome-wide survey and comprehensive expression profiling of Aux/IAA gene family in chickpea and soybean. FRONTIERS IN PLANT SCIENCE 2015; 6:918. [PMID: 26579165 PMCID: PMC4621760 DOI: 10.3389/fpls.2015.00918] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 10/12/2015] [Indexed: 05/07/2023]
Abstract
Auxin plays a central role in many aspects of plant growth and development. Auxin/Indole-3-Acetic Acid (Aux/IAA) genes cooperate with several other components in the perception and signaling of plant hormone auxin. An investigation of chickpea and soybean genomes revealed 22 and 63 putative Aux/IAA genes, respectively. These genes were classified into six subfamilies on the basis of phylogenetic analysis. Among 63 soybean Aux/IAA genes, 57 (90.5%) were found to be duplicated via whole genome duplication (WGD)/segmental events. Transposed duplication played a significant role in tandem arrangements between the members of different subfamilies. Analysis of Ka/Ks ratio of duplicated Aux/IAA genes revealed purifying selection pressure with restricted functional divergence. Promoter sequence analysis revealed several cis-regulatory elements related to auxin, abscisic acid, desiccation, salt, seed, and endosperm, indicating their role in development and stress responses. Expression analysis of chickpea and soybean Aux/IAA genes in various tissues and stages of development demonstrated tissue/stage specific differential expression. In soybean, at least 16 paralog pairs, duplicated via WGD/segmental events, showed almost indistinguishable expression pattern, but eight pairs exhibited significantly diverse expression patterns. Under abiotic stress conditions, such as desiccation, salinity and/or cold, many Aux/IAA genes of chickpea and soybean revealed differential expression. qRT-PCR analysis confirmed the differential expression patterns of selected Aux/IAA genes in chickpea. The analyses presented here provide insights on putative roles of chickpea and soybean Aux/IAA genes and will facilitate elucidation of their precise functions during development and abiotic stress responses.
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47
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Renny-Byfield S, Wendel JF. Doubling down on genomes: polyploidy and crop plants. AMERICAN JOURNAL OF BOTANY 2014; 101:1711-25. [PMID: 25090999 DOI: 10.3732/ajb.1400119] [Citation(s) in RCA: 212] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Polyploidy, or whole genome multiplication, is ubiquitous among angiosperms. Many crop species are relatively recent allopolyploids, resulting from interspecific hybridization and polyploidy. Thus, an appreciation of the evolutionary consequences of (allo)polyploidy is central to our understanding of crop plant domestication, agricultural improvement, and the evolution of angiosperms in general. Indeed, many recent insights into plant biology have been gleaned from polyploid crops, including, but not limited to wheat, tobacco, sugarcane, apple, and cotton. A multitude of evolutionary processes affect polyploid genomes, including rapid and substantial genome reorganization, transgressive gene expression alterations, gene fractionation, gene conversion, genome downsizing, and sub- and neofunctionalization of duplicate genes. Often these genomic changes are accompanied by heterosis, robustness, and the improvement of crop yield, relative to closely related diploids. Historically, however, the genome-wide analysis of polyploid crops has lagged behind those of diploid crops and other model organisms. This lag is partly due to the difficulties in genome assembly, resulting from the genomic complexities induced by combining two or more evolutionarily diverged genomes into a single nucleus and by the significant size of polyploid genomes. In this review, we explore the role of polyploidy in angiosperm evolution, the domestication process and crop improvement. We focus on the potential of modern technologies, particularly next-generation sequencing, to inform us on the patterns and processes governing polyploid crop improvement and phenotypic change subsequent to domestication.
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Affiliation(s)
- Simon Renny-Byfield
- Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa 50011 USA
| | - Jonathan F Wendel
- Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa 50011 USA
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48
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49
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Origin, inheritance, and gene regulatory consequences of genome dominance in polyploids. Proc Natl Acad Sci U S A 2014; 111:5283-8. [PMID: 24706847 DOI: 10.1073/pnas.1402475111] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Whole-genome duplications happen repeatedly in a typical flowering plant lineage. Following most ancient tetraploidies, the two subgenomes are distinguishable because one subgenome, the dominant subgenome, tends to have more genes than the other subgenome. Additionally, among retained pairs, the gene on the dominant subgenome tends to be expressed more than its recessive homeolog. Using comparative genomics, we show that genome dominance is heritable. The dominant subgenome of one postpolyploidy event remains dominant through a subsequent polyploidy event. We show that transposon-derived 24-nt RNAs target and cover the upstream region of retained genes preferentially when located on the recessive subgenome, and with little regard for a gene's level of expression. We hypothesize that small RNA (smRNA)-mediated silencing of transposons near genes causes position-effect down-regulation. Unlike 24-nt smRNA coverage, transposon coverage tracks gene expression, so not all transposons behave identically. We propose that successful ancient tetraploids begin as wide crosses between two lines, each evolved for different tradeoffs between transposon silencing and negative position effects on gene expression. We hypothesize that following a chaotic wide-cross/new tetraploid period, genes acquire their new expression balances based on differences in transposon coverage in the parents. We envision patches of silenceable transposon as quantitative cis-regulators of baseline transcription rate. Attractive solutions to heterosis and the C-value paradox are mentioned.
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50
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Renny-Byfield S, Gallagher JP, Grover CE, Szadkowski E, Page JT, Udall JA, Wang X, Paterson AH, Wendel JF. Ancient gene duplicates in Gossypium (cotton) exhibit near-complete expression divergence. Genome Biol Evol 2014; 6:559-71. [PMID: 24558256 PMCID: PMC3971588 DOI: 10.1093/gbe/evu037] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2014] [Indexed: 12/25/2022] Open
Abstract
Whole genome duplication (WGD) is widespread in flowering plants and is a driving force in angiosperm diversification. The redundancy introduced by WGD allows the evolution of novel gene interactions and functions, although the patterns and processes of diversification are poorly understood. We identified ∼ 2,000 pairs of paralogous genes in Gossypium raimondii (cotton) resulting from an approximately 60 My old 5- to 6-fold ploidy increase. Gene expression analyses revealed that, in G. raimondii, 99.4% of the gene pairs exhibit differential expression in at least one of the three tissues (petal, leaf, and seed), with 93% to 94% exhibiting differential expression on a per-tissue basis. For 1,666 (85%) pairs, differential expression was observed in all tissues. These observations were mirrored in a time series of G. raimondii seed, and separately in leaf, petal, and seed of G. arboreum, indicating expression level diversification before species divergence. A generalized linear model revealed 92.4% of the paralog pairs exhibited expression divergence, with most exhibiting significant gene and tissue interactions indicating complementary expression patterns in different tissues. These data indicate massive, near-complete expression level neo- and/or subfunctionalization among ancient gene duplicates, suggesting these processes are essential in their maintenance over ∼ 60 Ma.
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Affiliation(s)
- Simon Renny-Byfield
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa
| | - Joseph P. Gallagher
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa
| | - Corrinne E. Grover
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa
| | - Emmanuel Szadkowski
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa
| | - Justin T. Page
- Plant and Wildlife Science Department, Brigham Young University, Provo, Utah
| | - Joshua A. Udall
- Plant and Wildlife Science Department, Brigham Young University, Provo, Utah
| | - Xiyin Wang
- Plant Genome Mapping Laboratory, University of Georgia, Athens, Georgia
| | | | - Jonathan F. Wendel
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa
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