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Nguyen AK, Blacksmith MS, Kidd JM. Duplications and Retrogenes Are Numerous and Widespread in Modern Canine Genomic Assemblies. Genome Biol Evol 2024; 16:evae142. [PMID: 38946312 PMCID: PMC11259980 DOI: 10.1093/gbe/evae142] [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: 11/01/2023] [Revised: 05/08/2024] [Accepted: 06/24/2024] [Indexed: 07/02/2024] Open
Abstract
Recent years have seen a dramatic increase in the number of canine genome assemblies available. Duplications are an important source of evolutionary novelty and are also prone to misassembly. We explored the duplication content of nine canine genome assemblies using both genome self-alignment and read-depth approaches. We find that 8.58% of the genome is duplicated in the canFam4 assembly, derived from the German Shepherd Dog Mischka, including 90.15% of unplaced contigs. Highlighting the continued difficulty in properly assembling duplications, less than half of read-depth and assembly alignment duplications overlap, but the mCanLor1.2 Greenland wolf assembly shows greater concordance. Further study shows the presence of multiple segments that have alignments to four or more duplicate copies. These high-recurrence duplications correspond to gene retrocopies. We identified 3,892 candidate retrocopies from 1,316 parental genes in the canFam4 assembly and find that ∼8.82% of duplicated base pairs involve a retrocopy, confirming this mechanism as a major driver of gene duplication in canines. Similar patterns are found across eight other recent canine genome assemblies, with metrics supporting a greater quality of the PacBio HiFi mCanLor1.2 assembly. Comparison between the wolf and other canine assemblies found that 92% of retrocopy insertions are shared between assemblies. By calculating the number of generations since genome divergence, we estimate that new retrocopy insertions appear, on average, in 1 out of 3,514 births. Our analyses illustrate the impact of retrogene formation on canine genomes and highlight the variable representation of duplicated sequences among recently completed canine assemblies.
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Affiliation(s)
- Anthony K Nguyen
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Matthew S Blacksmith
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Jeffrey M Kidd
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
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2
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Thomas SK, Hoek KV, Ogoti T, Duong H, Angelovici R, Pires JC, Mendoza-Cozatl D, Washburn J, Schenck CA. Halophytes and heavy metals: A multi-omics approach to understand the role of gene and genome duplication in the abiotic stress tolerance of Cakile maritima. AMERICAN JOURNAL OF BOTANY 2024:e16310. [PMID: 38600732 DOI: 10.1002/ajb2.16310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 04/12/2024]
Abstract
PREMISE The origin of diversity is a fundamental biological question. Gene duplications are one mechanism that provides raw material for the emergence of novel traits, but evolutionary outcomes depend on which genes are retained and how they become functionalized. Yet, following different duplication types (polyploidy and tandem duplication), the events driving gene retention and functionalization remain poorly understood. Here we used Cakile maritima, a species that is tolerant to salt and heavy metals and shares an ancient whole-genome triplication with closely related salt-sensitive mustard crops (Brassica), as a model to explore the evolution of abiotic stress tolerance following polyploidy. METHODS Using a combination of ionomics, free amino acid profiling, and comparative genomics, we characterize aspects of salt stress response in C. maritima and identify retained duplicate genes that have likely enabled adaptation to salt and mild levels of cadmium. RESULTS Cakile maritima is tolerant to both cadmium and salt treatments through uptake of cadmium in the roots. Proline constitutes greater than 30% of the free amino acid pool in C. maritima and likely contributes to abiotic stress tolerance. We find duplicated gene families are enriched in metabolic and transport processes and identify key transport genes that may be involved in C. maritima abiotic stress tolerance. CONCLUSIONS These findings identify pathways and genes that could be used to enhance plant resilience and provide a putative understanding of the roles of duplication types and retention on the evolution of abiotic stress response.
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Affiliation(s)
- Shawn K Thomas
- Division of Biological Sciences, University of Missouri, Columbia, 65211, MO, USA
- Bioinformatics and Analytics Core, University of Missouri, Columbia, 65211, MO, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, 65211, MO, USA
| | - Kathryn Vanden Hoek
- Department of Biochemistry, University of Missouri, Columbia, 65211, MO, USA
| | - Tasha Ogoti
- Department of Computer Science, University of Missouri, Columbia, 65211, MO, USA
| | - Ha Duong
- Interdisciplinary Plant Group, University of Missouri, Columbia, 65211, MO, USA
- Department of Biochemistry, University of Missouri, Columbia, 65211, MO, USA
| | - Ruthie Angelovici
- Division of Biological Sciences, University of Missouri, Columbia, 65211, MO, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, 65211, MO, USA
| | - J Chris Pires
- Soil and Crop Sciences, Colorado State University, Fort Collins, 80523-1170, CO, USA
| | - David Mendoza-Cozatl
- Interdisciplinary Plant Group, University of Missouri, Columbia, 65211, MO, USA
- Division of Plant Sciences and Technology, University of Missouri, Columbia, 65211, MO, USA
| | - Jacob Washburn
- Interdisciplinary Plant Group, University of Missouri, Columbia, 65211, MO, USA
- Plant Genetics Research Unit, USDA-ARS, Columbia, 65211, MO, USA
| | - Craig A Schenck
- Interdisciplinary Plant Group, University of Missouri, Columbia, 65211, MO, USA
- Department of Biochemistry, University of Missouri, Columbia, 65211, MO, USA
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3
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Navarro-Quiles C, Lup SD, Muñoz-Nortes T, Candela H, Micol JL. The genetic and molecular basis of haploinsufficiency in flowering plants. TRENDS IN PLANT SCIENCE 2024; 29:72-85. [PMID: 37633803 DOI: 10.1016/j.tplants.2023.07.009] [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: 03/04/2023] [Revised: 07/15/2023] [Accepted: 07/19/2023] [Indexed: 08/28/2023]
Abstract
In diploid organisms, haploinsufficiency can be defined as the requirement for more than one fully functional copy of a gene. In contrast to most genes, whose loss-of-function alleles are recessive, loss-of-function alleles of haploinsufficient genes are dominant. However, forward and reverse genetic screens are biased toward obtaining recessive, loss-of-function mutations, and therefore, dominant mutations of all types are underrepresented in mutant collections. Despite this underrepresentation, haploinsufficient loci have intriguing implications for studies of genome evolution, gene dosage, stability of protein complexes, genetic redundancy, and gene expression. Here we review examples of haploinsufficiency in flowering plants and describe the underlying molecular mechanisms and evolutionary forces driving haploinsufficiency. Finally, we discuss the masking of haploinsufficiency by genetic redundancy, a widespread phenomenon among angiosperms.
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Affiliation(s)
- Carla Navarro-Quiles
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Spain
| | - Samuel Daniel Lup
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Spain
| | - Tamara Muñoz-Nortes
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Spain
| | - Héctor Candela
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Spain
| | - José Luis Micol
- Instituto de Bioingeniería, Universidad Miguel Hernández, Campus de Elche, 03202 Elche, Spain.
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4
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Clifton BD, Hariyani I, Kimura A, Luo F, Nguyen A, Ranz JM. Paralog transcriptional differentiation in the D. melanogaster-specific gene family Sdic across populations and spermatogenesis stages. Commun Biol 2023; 6:1069. [PMID: 37864070 PMCID: PMC10589255 DOI: 10.1038/s42003-023-05427-4] [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: 05/12/2023] [Accepted: 10/05/2023] [Indexed: 10/22/2023] Open
Abstract
How recently originated gene copies become stable genomic components remains uncertain as high sequence similarity of young duplicates precludes their functional characterization. The tandem multigene family Sdic is specific to Drosophila melanogaster and has been annotated across multiple reference-quality genome assemblies. Here we show the existence of a positive correlation between Sdic copy number and total expression, plus vast intrastrain differences in mRNA abundance among paralogs, using RNA-sequencing from testis of four strains with variable paralog composition. Single cell and nucleus RNA-sequencing data expose paralog expression differentiation in meiotic cell types within testis from third instar larva and adults. Additional RNA-sequencing across synthetic strains only differing in their Y chromosomes reveal a tissue-dependent trans-regulatory effect on Sdic: upregulation in testis and downregulation in male accessory gland. By leveraging paralog-specific expression information from tissue- and cell-specific data, our results elucidate the intraspecific functional diversification of a recently expanded tandem gene family.
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Affiliation(s)
- Bryan D Clifton
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, 92697, USA.
| | - Imtiyaz Hariyani
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, 92697, USA
| | - Ashlyn Kimura
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, 92697, USA
| | - Fangning Luo
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, 92697, USA
| | - Alvin Nguyen
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, 92697, USA
| | - José M Ranz
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, 92697, USA.
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5
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De Silva NP, Lee C, Battlay P, Fournier-Level A, Moore JL, Hodgins KA. Genome assembly of an Australian native grass species reveals a recent whole-genome duplication and biased gene retention of genes involved in stress response. Gigascience 2022; 12:giad034. [PMID: 37171129 PMCID: PMC10176504 DOI: 10.1093/gigascience/giad034] [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: 06/24/2022] [Revised: 01/04/2023] [Accepted: 04/24/2023] [Indexed: 05/13/2023] Open
Abstract
BACKGROUND The adaptive significance of polyploidy has been extensively debated, and chromosome-level genome assemblies of polyploids can provide insight into this. The Australian grass Bothriochloa decipiens belongs to the BCD clade, a group with a complex history of hybridization and polyploid. This is the first genome assembly and annotation of a species that belongs to this fascinating yet complex group. FINDINGS Using Illumina short reads, 10X Genomics linked reads, and Hi-C sequencing data, we assembled a highly contiguous genome of B. decipiens, with a total length of 1,218.22 Mb and scaffold N50 of 42.637 Mb. Comparative analysis revealed that the species experienced a relatively recent whole-genome duplication. We clustered the 20 major scaffolds, representing the 20 chromosomes, into the 2 subgenomes of the parental species using unique repeat signatures. We found evidence of biased fractionation and differences in the activity of transposable elements between the subgenomes prior to hybridization. Duplicates were enriched for genes involved in transcription and response to external stimuli, supporting a biased retention of duplicated genes following whole-genome duplication. CONCLUSIONS Our results support the hypotheses of a biased retention of duplicated genes following polyploidy and point to differences in repeat activity associated with subgenome dominance. B. decipiens is a widespread species with the ability to establish across many soil types, making it a prime candidate for climate change- resilient ecological restoration of Australian grasslands. This reference genome is a valuable resource for future population genomic research on Australian grasses.
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Affiliation(s)
- Nissanka P De Silva
- School of Biological Sciences, Monash University, Clayton, 3800 Victoria, Australia
| | - Christopher Lee
- School of Biological Sciences, Monash University, Clayton, 3800 Victoria, Australia
| | - Paul Battlay
- School of Biological Sciences, Monash University, Clayton, 3800 Victoria, Australia
| | - A Fournier-Level
- School of BioSciences, University of Melbourne, Melbourne, 3010 Victoria, Australia
| | - Joslin L Moore
- School of Biological Sciences, Monash University, Clayton, 3800 Victoria, Australia
- Arthur Rylah Institute for Environment Research, Heidelberg, 3084 Victoria, Australia
| | - Kathryn A Hodgins
- School of Biological Sciences, Monash University, Clayton, 3800 Victoria, Australia
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6
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The road less travelled? Exploring the nuanced evolutionary consequences of duplicated genes. Essays Biochem 2022; 66:737-744. [PMID: 36449319 DOI: 10.1042/ebc20220213] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 10/14/2022] [Accepted: 10/24/2022] [Indexed: 12/05/2022]
Abstract
Duplicated genes have long been appreciated as both substrates and catalysts of evolutionary processes. From even the simplest cell to complex multicellular animals and plants, duplicated genes have made immeasurable contributions to the phenotypic evolution of all life on Earth. Not merely drivers of morphological innovation and speciation events, however, gene duplications sculpt the evolution of genetic architecture in ways we are only just coming to understand now we have the experimental tools to do so. As such, the present article revisits our understanding of the ways in which duplicated genes evolve, examining closely the various fates they can adopt in light of recent work that yields insights from studies of paralogues from across the tree of life that challenge the classical framework.
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7
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Cui F, Ye X, Li X, Yang Y, Hu Z, Overmyer K, Brosché M, Yu H, Salojärvi J. Chromosome-level genome assembly of the diploid blueberry Vaccinium darrowii provides insights into its subtropical adaptation and cuticle synthesis. PLANT COMMUNICATIONS 2022; 3:100307. [PMID: 35605198 PMCID: PMC9284290 DOI: 10.1016/j.xplc.2022.100307] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 02/09/2022] [Accepted: 02/24/2022] [Indexed: 05/25/2023]
Abstract
Vaccinium darrowii is a subtropical wild blueberry species that has been used to breed economically important southern highbush cultivars. The adaptive traits of V. darrowii to subtropical climates can provide valuable information for breeding blueberry and perhaps other plants, especially against the background of global warming. Here, we assembled the V. darrowii genome into 12 pseudochromosomes using Oxford Nanopore long reads complemented with Hi-C scaffolding technologies, and we predicted 41 815 genes using RNA-sequencing evidence. Syntenic analysis across three Vaccinium species revealed a highly conserved genome structure, with the highest collinearity between V. darrowii and Vaccinium corymbosum. This conserved genome structure may explain the high fertility observed during crossbreeding of V. darrowii with other blueberry cultivars. Analysis of gene expansion and tandem duplication indicated possible roles for defense- and flowering-associated genes in the adaptation of V. darrowii to the subtropics. Putative SOC1 genes in V. darrowii were identified based on phylogeny and expression analysis. Blueberries are covered in a thick cuticle layer and contain anthocyanins, which confer their powdery blue color. Using RNA sequencing, we delineated the cuticle biosynthesis pathways of Vaccinium species in V. darrowii. This result can serve as a reference for breeding berries whose colors are appealing to customers. The V. darrowii reference genome, together with the unique traits of this species, including its diploid genome, short vegetative phase, and high compatibility in hybridization with other blueberries, make V. darrowii a potential research model for blueberry species.
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Affiliation(s)
- Fuqiang Cui
- College of Forestry and Biotechnology, State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou 311300, China.
| | - Xiaoxue Ye
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan 571101, China; School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Xiaoxiao Li
- College of Forestry and Biotechnology, State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou 311300, China
| | - Yifan Yang
- College of Forestry and Biotechnology, State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou 311300, China
| | - Zhubing Hu
- State Key Laboratory of Cotton Biology, Department of Biology, Institute of Plant Stress Biology, Henan University, Kaifeng, China
| | - Kirk Overmyer
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and the Viikki Plant Science Centre, University of Helsinki, PO Box 65 (Viikinkaari 1), 00014 Helsinki, Finland
| | - Mikael Brosché
- Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and the Viikki Plant Science Centre, University of Helsinki, PO Box 65 (Viikinkaari 1), 00014 Helsinki, Finland
| | - Hong Yu
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing, China
| | - Jarkko Salojärvi
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore; Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and the Viikki Plant Science Centre, University of Helsinki, PO Box 65 (Viikinkaari 1), 00014 Helsinki, Finland.
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8
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Gera T, Jonas F, More R, Barkai N. Evolution of binding preferences among whole-genome duplicated transcription factors. eLife 2022; 11:73225. [PMID: 35404235 PMCID: PMC9000951 DOI: 10.7554/elife.73225] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 01/20/2022] [Indexed: 01/10/2023] Open
Abstract
Throughout evolution, new transcription factors (TFs) emerge by gene duplication, promoting growth and rewiring of transcriptional networks. How TF duplicates diverge was studied in a few cases only. To provide a genome-scale view, we considered the set of budding yeast TFs classified as whole-genome duplication (WGD)-retained paralogs (~35% of all specific TFs). Using high-resolution profiling, we find that ~60% of paralogs evolved differential binding preferences. We show that this divergence results primarily from variations outside the DNA-binding domains (DBDs), while DBD preferences remain largely conserved. Analysis of non-WGD orthologs revealed uneven splitting of ancestral preferences between duplicates, and the preferential acquiring of new targets by the least conserved paralog (biased neo/sub-functionalization). Interactions between paralogs were rare, and, when present, occurred through weak competition for DNA-binding or dependency between dimer-forming paralogs. We discuss the implications of our findings for the evolutionary design of transcriptional networks.
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Affiliation(s)
- Tamar Gera
- Department of Molecular Genetics, Weizmann Institute of Science
| | - Felix Jonas
- Department of Molecular Genetics, Weizmann Institute of Science
| | - Roye More
- Department of Molecular Genetics, Weizmann Institute of Science
| | - Naama Barkai
- Department of Molecular Genetics, Weizmann Institute of Science
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9
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Genome-wide survey of sugar beet (Beta vulgaris subsp. vulgaris) Dof transcription factors reveals structural diversity, evolutionary expansion and involvement in taproot development and biotic stress response. Biologia (Bratisl) 2021. [DOI: 10.1007/s11756-021-00777-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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Gaynor ML, Lim-Hing S, Mason CM. Impact of genome duplication on secondary metabolite composition in non-cultivated species: a systematic meta-analysis. ANNALS OF BOTANY 2020; 126:363-376. [PMID: 32504537 PMCID: PMC7424755 DOI: 10.1093/aob/mcaa107] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 06/02/2020] [Indexed: 05/05/2023]
Abstract
BACKGROUND AND AIMS Whole-genome duplication is known to influence ecological interactions and plant physiology; however, despite abundant case studies, much is still unknown about the typical impact of genome duplication on plant secondary metabolites (PSMs). In this study, we assessed the impact of polyploidy events on PSM characteristics in non-cultivated plants. METHODS We conducted a systematic review and meta-analysis to compare composition and concentration of PSMs among closely related plant species or species complexes differing in ploidy level. KEY RESULTS We assessed 53 studies that focus on PSMs among multiple cytotypes, of which only 14 studies compared concentration quantitatively among cytotypes. We found that whole-genome duplication can have a significant effect on PSM concentration; however, these effects are highly inconsistent. CONCLUSION Overall, there was no consistent effect of whole-genome duplication on PSM concentrations or profiles.
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Affiliation(s)
- Michelle L Gaynor
- Department of Biology, University of Central Florida, Orlando, FL, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL, USA
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - Simone Lim-Hing
- Department of Biology, University of Central Florida, Orlando, FL, USA
- Department of Plant Biology, University of Georgia, Athens, GA, USA
| | - Chase M Mason
- Department of Biology, University of Central Florida, Orlando, FL, USA
- For correspondence. E-mail
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11
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Shi T, Rahmani RS, Gugger PF, Wang M, Li H, Zhang Y, Li Z, Wang Q, Van de Peer Y, Marchal K, Chen J. Distinct Expression and Methylation Patterns for Genes with Different Fates following a Single Whole-Genome Duplication in Flowering Plants. Mol Biol Evol 2020; 37:2394-2413. [PMID: 32343808 PMCID: PMC7403625 DOI: 10.1093/molbev/msaa105] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
For most sequenced flowering plants, multiple whole-genome duplications (WGDs) are found. Duplicated genes following WGD often have different fates that can quickly disappear again, be retained for long(er) periods, or subsequently undergo small-scale duplications. However, how different expression, epigenetic regulation, and functional constraints are associated with these different gene fates following a WGD still requires further investigation due to successive WGDs in angiosperms complicating the gene trajectories. In this study, we investigate lotus (Nelumbo nucifera), an angiosperm with a single WGD during the K-pg boundary. Based on improved intraspecific-synteny identification by a chromosome-level assembly, transcriptome, and bisulfite sequencing, we explore not only the fundamental distinctions in genomic features, expression, and methylation patterns of genes with different fates after a WGD but also the factors that shape post-WGD expression divergence and expression bias between duplicates. We found that after a WGD genes that returned to single copies show the highest levels and breadth of expression, gene body methylation, and intron numbers, whereas the long-retained duplicates exhibit the highest degrees of protein-protein interactions and protein lengths and the lowest methylation in gene flanking regions. For those long-retained duplicate pairs, the degree of expression divergence correlates with their sequence divergence, degree in protein-protein interactions, and expression level, whereas their biases in expression level reflecting subgenome dominance are associated with the bias of subgenome fractionation. Overall, our study on the paleopolyploid nature of lotus highlights the impact of different functional constraints on gene fate and duplicate divergence following a single WGD in plant.
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Affiliation(s)
- Tao Shi
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
| | - Razgar Seyed Rahmani
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
| | - Paul F Gugger
- Appalachian Laboratory, University of Maryland Center for Environmental Science, Frostburg, MD
| | - Muhua Wang
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, China
| | - Hui Li
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yue Zhang
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhizhong Li
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qingfeng Wang
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- Sino-African Joint Research Center, Chinese Academy of Sciences, Wuhan, China
| | - Yves Van de Peer
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Centre for Plant Systems Biology, VIB, Ghent, Belgium
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- College of Horticulture, Nanjing Agricultural University, Nanjing, China
| | - Kathleen Marchal
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Department of Information Technology, IDLab, IMEC, Ghent University, Ghent, Belgium
| | - Jinming Chen
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
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12
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Defoort J, Van de Peer Y, Carretero-Paulet L. The Evolution of Gene Duplicates in Angiosperms and the Impact of Protein-Protein Interactions and the Mechanism of Duplication. Genome Biol Evol 2020; 11:2292-2305. [PMID: 31364708 PMCID: PMC6735927 DOI: 10.1093/gbe/evz156] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2019] [Indexed: 01/17/2023] Open
Abstract
Gene duplicates, generated through either whole genome duplication (WGD) or small-scale duplication (SSD), are prominent in angiosperms and are believed to play an important role in adaptation and in generating evolutionary novelty. Previous studies reported contrasting evolutionary and functional dynamics of duplicate genes depending on the mechanism of origin, a behavior that is hypothesized to stem from constraints to maintain the relative dosage balance between the genes concerned and their interaction context. However, the mechanisms ultimately influencing loss and retention of gene duplicates over evolutionary time are not yet fully elucidated. Here, by using a robust classification of gene duplicates in Arabidopsis thaliana, Solanum lycopersicum, and Zea mays, large RNAseq expression compendia and an extensive protein-protein interaction (PPI) network from Arabidopsis, we investigated the impact of PPIs on the differential evolutionary and functional fate of WGD and SSD duplicates. In all three species, retained WGD duplicates show stronger constraints to diverge at the sequence and expression level than SSD ones, a pattern that is also observed for shared PPI partners between Arabidopsis duplicates. PPIs are preferentially distributed among WGD duplicates and specific functional categories. Furthermore, duplicates with PPIs tend to be under stronger constraints to evolve than their counterparts without PPIs regardless of their mechanism of origin. Our results support dosage balance constraint as a specific property of genes involved in biological interactions, including physical PPIs, and suggest that additional factors may be differently influencing the evolution of genes following duplication, depending on the species, time, and mechanism of origin.
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Affiliation(s)
- Jonas Defoort
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Belgium.,VIB Center for Plant Systems Biology, Ghent, Belgium.,Bioinformatics Institute Ghent, Ghent University, Belgium
| | - Yves Van de Peer
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Belgium.,VIB Center for Plant Systems Biology, Ghent, Belgium.,Bioinformatics Institute Ghent, Ghent University, Belgium.,Department of Biochemistry, Genetics and Microbiology, University of Pretoria, South Africa
| | - Lorenzo Carretero-Paulet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Belgium.,VIB Center for Plant Systems Biology, Ghent, Belgium.,Bioinformatics Institute Ghent, Ghent University, Belgium
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Wilson AE, Tian L. Phylogenomic analysis of UDP-dependent glycosyltransferases provides insights into the evolutionary landscape of glycosylation in plant metabolism. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 100:1273-1288. [PMID: 31446648 DOI: 10.1111/tpj.14514] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/09/2019] [Accepted: 08/19/2019] [Indexed: 05/05/2023]
Abstract
Glycosylated metabolites generated by UDP-dependent glycosyltransferases (UGTs) play critical roles in plant interactions with the environment as well as human and animal nutrition. The evolution of plant UGTs has previously been explored, but with a limited taxon sampling. In this study, 65 fully sequenced plant genomes were analyzed, and stringent criteria for selection of candidate UGTs were applied to ensure a more comprehensive taxon sampling and reliable sequence inclusion. In addition to revealing the overall evolutionary landscape of plant UGTs, the phylogenomic analysis also resolved the phylogenetic association of UGTs from free-sporing plants and gymnosperms, and identified an additional UGT group (group R) in seed plants. Furthermore, lineage-specific expansions and contractions of UGT groups were detected in angiosperms, with the total number of UGTs per genome remaining constant generally. The loss of group Q UGTs in Poales and Brassicales, rather than functional convergence in the group Q containing species, was supported by a gene tree of group Q UGTs sampled from many species, and further corroborated by the absence of group Q homologs on the syntenic chromosomal regions in Arabidopsis thaliana (Brassicales). Branch-site analyses of the group Q UGT gene tree allowed for identification of branches and amino acid sites that experienced episodic positive selection. The positively selected sites are located on the surface of a representative group Q UGT (PgUGT95B2), away from the active site, suggesting their role in protein folding/stability or protein-protein interactions.
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Affiliation(s)
- Alexander E Wilson
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA
| | - Li Tian
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA
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Vaattovaara A, Brandt B, Rajaraman S, Safronov O, Veidenberg A, Luklová M, Kangasjärvi J, Löytynoja A, Hothorn M, Salojärvi J, Wrzaczek M. Mechanistic insights into the evolution of DUF26-containing proteins in land plants. Commun Biol 2019; 2:56. [PMID: 30775457 PMCID: PMC6368629 DOI: 10.1038/s42003-019-0306-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 01/14/2019] [Indexed: 01/01/2023] Open
Abstract
Large protein families are a prominent feature of plant genomes and their size variation is a key element for adaptation. However, gene and genome duplications pose difficulties for functional characterization and translational research. Here we infer the evolutionary history of the DOMAIN OF UNKNOWN FUNCTION (DUF) 26-containing proteins. The DUF26 emerged in secreted proteins. Domain duplications and rearrangements led to the appearance of CYSTEINE-RICH RECEPTOR-LIKE PROTEIN KINASES (CRKs) and PLASMODESMATA-LOCALIZED PROTEINS (PDLPs). The DUF26 is land plant-specific but structural analyses of PDLP ectodomains revealed strong similarity to fungal lectins and thus may constitute a group of plant carbohydrate-binding proteins. CRKs expanded through tandem duplications and preferential retention of duplicates following whole genome duplications, whereas PDLPs evolved according to the dosage balance hypothesis. We propose that new gene families mainly expand through small-scale duplications, while fractionation and genetic drift after whole genome multiplications drive families towards dosage balance.
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Affiliation(s)
- Aleksia Vaattovaara
- Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, VIPS, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1 (POB65), FI-00014 Helsinki, Finland
| | - Benjamin Brandt
- Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Sitaram Rajaraman
- Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, VIPS, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1 (POB65), FI-00014 Helsinki, Finland
| | - Omid Safronov
- Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, VIPS, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1 (POB65), FI-00014 Helsinki, Finland
| | - Andres Veidenberg
- Institute of Biotechnology, University of Helsinki, Viikinkaari 5 (POB56), FI-00014 Helsinki, Finland
| | - Markéta Luklová
- Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, VIPS, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1 (POB65), FI-00014 Helsinki, Finland
- Present Address: Laboratory of Plant Molecular Biology, Institute of Biophysics AS CR, v.v.i. and CEITEC—Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic
| | - Jaakko Kangasjärvi
- Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, VIPS, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1 (POB65), FI-00014 Helsinki, Finland
| | - Ari Löytynoja
- Institute of Biotechnology, University of Helsinki, Viikinkaari 5 (POB56), FI-00014 Helsinki, Finland
| | - Michael Hothorn
- Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Jarkko Salojärvi
- Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, VIPS, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1 (POB65), FI-00014 Helsinki, Finland
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551 Singapore
| | - Michael Wrzaczek
- Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, VIPS, Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1 (POB65), FI-00014 Helsinki, Finland
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Chai W, Peng X, Liu B, Wang J, Zhu Z, Liu Y, Zhao K, Cheng B, Si W, Jiang H. Comparative Genomics, Whole-Genome Re-sequencing and Expression Profile Analysis of Nucleobase:Cation Symporter 2 ( NCS2) Genes in Maize. FRONTIERS IN PLANT SCIENCE 2018; 9:856. [PMID: 30002663 PMCID: PMC6031955 DOI: 10.3389/fpls.2018.00856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/01/2018] [Indexed: 06/08/2023]
Abstract
Nucleobase:cation symporter 2 (NCS2) proteins are important for the transport of free nucleobases, participating in diverse plant growth and developmental processes, as well as response to abiotic stress. To date, a comprehensive analysis of the NCS2 gene family has not been performed in maize. In this study, we conducted a comparative genomics analysis of NCS2 genes in 28 plant species, ranging from aquatic algae to land plants, concentrating mainly on maize. Gene duplication events contributed to the expansion of NCS2 genes from lower aquatic plants to higher angiosperms, and whole-genome/segmental and single-gene duplication events were responsible for the expansion of the maize NCS2 gene family. Phylogenetic construction showed three NCS2 subfamilies, I, II, and III. According to homology-based relationships, members of subfamily I are NCS2/AzgA-like genes, whereas those in subfamilies II and III are NCS2/NATs. Moreover, subfamily I exhibited ancient origins. A motif compositional analysis showed that one symbolic motif (motif 4) of the NCS2/NAT genes was absent in subfamily I. In maize, three NCS2/AzgA-like and 21 NCS2/NAT genes were identified, and purifying selection influenced the duplication of maize NCS2 genes. Additionally, a population genetic analysis of NCS2 genes revealed that ZmNCS2-21 showed the greatest diversity between the 78 inbred and 22 wild surveyed maize populations. An expression profile analysis using transcriptome data and quantitative real-time PCR revealed that NCS2 genes in maize are involved in diverse developmental processes and responses to abiotic stresses, including abscisic acid, salt (NaCl), polyethylene glycol, and low (4°C) and high (42°C) temperatures. ZmNCS2 genes with relatively close relationships had similar expression patterns, strongly indicating functional redundancy. Finally, ZmNCS2-16 and ZmNCS2-23 localize in the plasma membrane, which confirmed their predicted membrane structures. These results provide a foundation for future studies regarding the functions of ZmNCS2 proteins, particularly those with potentially important roles in plant responses to abiotic stresses.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Weina Si
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, China
| | - Haiyang Jiang
- National Engineering Laboratory of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei, China
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Kaltenegger E, Leng S, Heyl A. The effects of repeated whole genome duplication events on the evolution of cytokinin signaling pathway. BMC Evol Biol 2018; 18:76. [PMID: 29843594 PMCID: PMC5975490 DOI: 10.1186/s12862-018-1153-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 03/14/2018] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND It is thought that after whole-genome duplications (WGDs), a large fraction of the duplicated gene copies is lost over time while few duplicates are retained. Which factors promote survival or death of a duplicate remains unclear and the underlying mechanisms are poorly understood. According to the model of gene dosage balance, genes encoding interacting proteins are predicted to be preferentially co-retained after WGDs. Among these are genes encoding proteins involved in complexes or in signal transduction. RESULTS We have investigated the way that repeated WGDs during land plant evolution have affected cytokinin signaling to study patterns of gene duplicability and co-retention in this important signal transduction pathway. Through the integration of phylogenetic analyses with comparisons of genome collinearity, we have found that signal input mediated by cytokinin receptors proved to be highly conserved over long evolutionary time-scales, with receptors showing predominantly gene loss after repeated WGDs. However, the downstream elements, e,g. response regulators, were mainly retained after WGDs and thereby formed gene families in most plant lineages. CONCLUSIONS Gene dosage balance between the interacting components indicated by co-retention after WGDs seems to play a minor role in the evolution of cytokinin signaling pathway. Overall, core genes of cytokinin signaling show a highly heterogeneous pattern of gene retention after WGD, reflecting complex relationships between the various factors that shape the long-term fate of a duplicated gene.
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Affiliation(s)
- Elisabeth Kaltenegger
- Department Biochemical Ecology and Molecular Evolution, Botanical Institute, Christian-Albrechts-University, Kiel, Germany
- Institute of Applied Genetics, Freie Universität Berlin, Berlin, Germany
| | - Svetlana Leng
- Institute of Applied Genetics, Freie Universität Berlin, Berlin, Germany
| | - Alexander Heyl
- Institute of Applied Genetics, Freie Universität Berlin, Berlin, Germany
- Biology Department, Adelphi University, Garden City, USA
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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: 179] [Impact Index Per Article: 29.8] [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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18
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Multiple large-scale gene and genome duplications during the evolution of hexapods. Proc Natl Acad Sci U S A 2018; 115:4713-4718. [PMID: 29674453 DOI: 10.1073/pnas.1710791115] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Polyploidy or whole genome duplication (WGD) is a major contributor to genome evolution and diversity. Although polyploidy is recognized as an important component of plant evolution, it is generally considered to play a relatively minor role in animal evolution. Ancient polyploidy is found in the ancestry of some animals, especially fishes, but there is little evidence for ancient WGDs in other metazoan lineages. Here we use recently published transcriptomes and genomes from more than 150 species across the insect phylogeny to investigate whether ancient WGDs occurred during the evolution of Hexapoda, the most diverse clade of animals. Using gene age distributions and phylogenomics, we found evidence for 18 ancient WGDs and six other large-scale bursts of gene duplication during insect evolution. These bursts of gene duplication occurred in the history of lineages such as the Lepidoptera, Trichoptera, and Odonata. To further corroborate the nature of these duplications, we evaluated the pattern of gene retention from putative WGDs observed in the gene age distributions. We found a relatively strong signal of convergent gene retention across many of the putative insect WGDs. Considering the phylogenetic breadth and depth of the insect phylogeny, this observation is consistent with polyploidy as we expect dosage balance to drive the parallel retention of genes. Together with recent research on plant evolution, our hexapod results suggest that genome duplications contributed to the evolution of two of the most diverse lineages of eukaryotes on Earth.
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