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Zhao Y, Liu G, Yang F, Liang Y, Gao Q, Xiang C, Li X, Yang R, Zhang G, Jiang H, Yu L, Yang S. Multilayered regulation of secondary metabolism in medicinal plants. MOLECULAR HORTICULTURE 2023; 3:11. [PMID: 37789448 PMCID: PMC10514987 DOI: 10.1186/s43897-023-00059-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 04/27/2023] [Indexed: 10/05/2023]
Abstract
Medicinal plants represent a huge reservoir of secondary metabolites (SMs), substances with significant pharmaceutical and industrial potential. However, obtaining secondary metabolites remains a challenge due to their low-yield accumulation in medicinal plants; moreover, these secondary metabolites are produced through tightly coordinated pathways involving many spatiotemporally and environmentally regulated steps. The first regulatory layer involves a complex network of transcription factors; a second, more recently discovered layer of complexity in the regulation of SMs is epigenetic modification, such as DNA methylation, histone modification and small RNA-based mechanisms, which can jointly or separately influence secondary metabolites by regulating gene expression. Here, we summarize the findings in the fields of genetic and epigenetic regulation with a special emphasis on SMs in medicinal plants, providing a new perspective on the multiple layers of regulation of gene expression.
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Affiliation(s)
- Yan Zhao
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Guanze Liu
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
| | - Feng Yang
- Institute of Chinese Medicinal Materials, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yanli Liang
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Qingqing Gao
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Chunfan Xiang
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Xia Li
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Run Yang
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Guanghui Zhang
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Huifeng Jiang
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
| | - Lei Yu
- College of Agronomy, Yunnan Urban Agricultural Engineering and Technological Research Center, Kunming University, Kunming, 650214, China.
| | - Shengchao Yang
- Key Laboratory of Medicinal Plant Biology of Yunnan Province, National & Local Joint Engineering Research Center on Germplasms Innovation & Utilization of Chinese Medicinal Materials in Southwest China, Yunnan Agricultural University, 650201, Kunming, China.
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Zhang YX, Niu YQ, Wang XF, Wang ZH, Wang ML, Yang J, Wang YG, Zhang WJ, Song ZP, Li LF. Phenotypic and transcriptomic responses of the shade-grown species Panax ginseng to variable light conditions. ANNALS OF BOTANY 2022; 130:749-762. [PMID: 35961674 PMCID: PMC9670753 DOI: 10.1093/aob/mcac105] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/10/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND AND AIMS Elucidating how plant species respond to variable light conditions is important to understand the ecological adaptation to heterogeneous natural habitats. Plant performance and its underlying gene regulatory network have been well documented in sun-grown plants. However, the phenotypic and molecular responses of shade-grown plants under variable light conditions have remained largely unclear. METHODS We assessed the differences in phenotypic performance between Panax ginseng (shade-grown) and Arabidopsis thaliana (sun-grown) under sunlight, shade and deep-shade conditions. To further address the molecular bases underpinning the phenotypic responses, we compared time-course transcriptomic expression profiling and candidate gene structures between the two species. KEY RESULTS Our results show that, compared with arabidopsis, ginseng plants not only possess a lower degree of phenotypic plasticity among the three light conditions, but also exhibit higher photosynthetic efficiency under shade and deep-shade conditions. Further comparisons of the gene expression and structure reveal that differential transcriptional regulation together with increased copy number of photosynthesis-related genes (e.g. electron transfer and carbon fixation) may improve the photosynthetic efficiency of ginseng plants under the two shade conditions. In contrast, the inactivation of phytochrome-interacting factors (i.e. absent and no upregulation of the PIF genes) are potentially associated with the observed low degree of phenotypic plasticity of ginseng plants under variable light conditions. CONCLUSIONS Our study provides new insights into how shade-grown plants respond to variable light conditions. Candidate genes related to shade adaptation in ginseng provide valuable genetic resources for future molecular breeding of high-density planting crops.
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Affiliation(s)
- Yu-Xin Zhang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yu-Qian Niu
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xin-Feng Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Zhen-Hui Wang
- Department of Agronomy, Jilin Agricultural University, Changchun 130118, China
| | - Meng-Li Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Ji Yang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yu-Guo Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Wen-Ju Zhang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Zhi-Ping Song
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Lin-Feng Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China
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Sun M, Zhang M, Chen X, Liu Y, Liu B, Li J, Wang R, Zhao K, Wu J. Rearrangement and domestication as drivers of Rosaceae mitogenome plasticity. BMC Biol 2022; 20:181. [PMID: 35986276 PMCID: PMC9392253 DOI: 10.1186/s12915-022-01383-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 08/04/2022] [Indexed: 11/10/2022] Open
Abstract
Background The mitochondrion is an important cellular component in plants and that functions in producing vital energy for the cell. However, the evolution and structure of mitochondrial genomes (mitogenomes) remain unclear in the Rosaceae family. In this study, we assembled 34 Rosaceae mitogenomes and characterized genome variation, rearrangement rate, and selection signal variation within these mitogenomes. Results Comparative analysis of six genera from the Amygdaloideae and five from the Rosoideae subfamilies of Rosaceae revealed that three protein-coding genes were absent from the mitogenomes of five Rosoideae genera. Positive correlations between genome size and repeat content were identified in 38 Rosaceae mitogenomes. Twenty repeats with high recombination frequency (> 50%) provided evidence for predominant substoichiometric conformation of the mitogenomes. Variations in rearrangement rates were identified between eleven genera, and within the Pyrus, Malus, Prunus, and Fragaria genera. Based on population data, phylogenetic inferences from Pyrus mitogenomes supported two distinct maternal lineages of Asian cultivated pears. A Pyrus-specific deletion (DEL-D) in selective sweeps was identified based on the assembled genomes and population data. After the DEL-D sequence fragments originally arose, they may have experienced a subsequent doubling event via homologous recombination and sequence transfer in the Amygdaloideae; afterwards, this variant sequence may have significantly expanded to cultivated groups, thereby improving adaptation during the domestication process. Conclusions This study characterizes the variations in gene content, genome size, rearrangement rate, and the impact of domestication in Rosaceae mitogenomes and provides insights into their structural variation patterns and phylogenetic relationships. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01383-3.
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Wang ZH, Wang XF, Lu T, Li MR, Jiang P, Zhao J, Liu ST, Fu XQ, Wendel JF, Van de Peer Y, Liu B, Li LF. Reshuffling of the ancestral core-eudicot genome shaped chromatin topology and epigenetic modification in Panax. Nat Commun 2022; 13:1902. [PMID: 35393424 PMCID: PMC8989883 DOI: 10.1038/s41467-022-29561-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 03/23/2022] [Indexed: 12/21/2022] Open
Abstract
All extant core-eudicot plants share a common ancestral genome that has experienced cyclic polyploidizations and (re)diploidizations. Reshuffling of the ancestral core-eudicot genome generates abundant genomic diversity, but the role of this diversity in shaping the hierarchical genome architecture, such as chromatin topology and gene expression, remains poorly understood. Here, we assemble chromosome-level genomes of one diploid and three tetraploid Panax species and conduct in-depth comparative genomic and epigenomic analyses. We show that chromosomal interactions within each duplicated ancestral chromosome largely maintain in extant Panax species, albeit experiencing ca. 100–150 million years of evolution from a shared ancestor. Biased genetic fractionation and epigenetic regulation divergence during polyploidization/(re)diploidization processes generate remarkable biochemical diversity of secondary metabolites in the Panax genus. Our study provides a paleo-polyploidization perspective of how reshuffling of the ancestral core-eudicot genome leads to a highly dynamic genome and to the metabolic diversification of extant eudicot plants. The role of polyploidization generated genomic diversity in shaping the hierarchical genome architecture remains unclear. Here, the authors show that repatterning of the ancestral eudicot genome has resulted in multi-dimensional genome plasticity and secondary metabolite diversification via comparisons of Panax genomes.
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Affiliation(s)
- Zhen-Hui Wang
- Faculty of Agronomy, Jilin Agricultural University, 130118, Changchun, China.,Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, 200438, Shanghai, China.,Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, 130024, Changchun, China
| | - Xin-Feng Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Tianyuan Lu
- McGill University and Genome Quebec Innovation Center, Montreal, QC, H3A 0G1, Canada
| | - Ming-Rui Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Peng Jiang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, 130024, Changchun, China
| | - Jing Zhao
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, 130024, Changchun, China
| | - Si-Tong Liu
- School of Life Sciences, Jilin University, 130061, Changchun, China
| | - Xue-Qi Fu
- School of Life Sciences, Jilin University, 130061, Changchun, China
| | - Jonathan F Wendel
- Department of Ecology, Evolution & Organismal Biology, Iowa State University, Ames, IA, 50011, USA
| | - Yves Van de Peer
- Department of Plant Biotechnology and Bioinformatics, Ghent University and VIB Center for Plant Systems Biology, Gent, Belgium. .,Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa. .,College of Horticulture, Academy for Advanced Interdisciplinary Studies, Nanjing Agricultural University, 210095, Nanjing, China.
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, 130024, Changchun, China.
| | - Lin-Feng Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, 200438, Shanghai, China.
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Guo W, Ma H, Wang CZ, Wan JY, Yao H, Yuan CS. Epigenetic Studies of Chinese Herbal Medicine: Pleiotropic Role of DNA Methylation. Front Pharmacol 2021; 12:790321. [PMID: 34950039 PMCID: PMC8688941 DOI: 10.3389/fphar.2021.790321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 11/22/2021] [Indexed: 12/03/2022] Open
Abstract
Accumulating knowledge has been achieved on DNA methylation participating in numerous cellular processes and multiple human diseases; however, few studies have addressed the pleiotropic role of DNA methylation in Chinese herbal medicine (CHM). CHM has been used worldwide for the prevention and treatment of multiple diseases. Newly developed epigenetic techniques have brought great opportunities for the development of CHM. In this review, we summarize the DNA methylation studies and portray the pleiotropic role of DNA methylation in CHM. DNA methylation serves as a mediator participating in plant responses to environmental factors, and thus affecting CHM medicinal plants growth and bioactive compound biosynthesis which are vital for therapeutic effects. Furthermore, DNA methylation helps to uncover the pharmaceutical mechanisms of CHM formulae, herbs, and herbal-derived compounds. It also provides scientific validation for constitution theory and other essential issues of CHM. This newly developed field of DNA methylation is up-and-coming to address many complicated scientific questions of CHM; it thus not only promotes disease treatment but also facilitates health maintenance.
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Affiliation(s)
- Wenqian Guo
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.,National Institute of TCM Constitution and Preventive Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Han Ma
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.,National Institute of TCM Constitution and Preventive Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Chong-Zhi Wang
- Tang Center for Herbal Medicine Research, The University of Chicago, Chicago, IL, United States.,Department of Anesthesia and Critical Care, The University of Chicago, Chicago, IL, United States
| | - Jin-Yi Wan
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.,National Institute of TCM Constitution and Preventive Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Haiqiang Yao
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.,National Institute of TCM Constitution and Preventive Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Chun-Su Yuan
- Tang Center for Herbal Medicine Research, The University of Chicago, Chicago, IL, United States.,Department of Anesthesia and Critical Care, The University of Chicago, Chicago, IL, United States
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Li MR, Ding N, Lu T, Zhao J, Wang ZH, Jiang P, Liu ST, Wang XF, Liu B, Li LF. Evolutionary Contribution of Duplicated Genes to Genome Evolution in the Ginseng Species Complex. Genome Biol Evol 2021; 13:6169528. [PMID: 33713106 PMCID: PMC8103499 DOI: 10.1093/gbe/evab051] [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] [Accepted: 03/06/2021] [Indexed: 11/22/2022] Open
Abstract
Genes duplicated by whole genome duplication (WGD) and small-scale duplication (SSD) have played important roles in adaptive evolution of all flowering plants. However, it still remains underinvestigated how the distinct models of duplication events and their contending evolutionary patterns have shaped the genome and epigenomes of extant plant species. In this study, we investigated the contribution of the WGD- and SSD-derived duplicate genes to the genome evolution of one diploid and three closely related allotetraploid Panax species based on genome, methylome, and proteome data sets. Our genome-wide comparative analyses revealed that although the ginseng species complex was recently diverged, they have evolved distinct overall patterns of nucleotide variation, cytosine methylation, and protein-level expression. In particular, genetic and epigenetic asymmetries observed in the recent WGD-derived genes are largely consistent across the ginseng species complex. In addition, our results revealed that gene duplicates generated by ancient WGD and SSD mechanisms exhibited distinct evolutionary patterns. We found the ancient WGD-derived genes (i.e., ancient collinear gene) are genetically more conserved and hypomethylated at the cytosine sites. In contrast, some of the SSD-derived genes (i.e., dispersal duplicated gene) showed hypermethylation and high variance in nucleotide variation pattern. Functional enrichment analyses of the duplicated genes indicated that adaptation-related traits (i.e., photosynthesis) created during the distant ancient WGDs are further strengthened by both the more recent WGD and SSD. Together, our findings suggest that different types of duplicated genes may have played distinct but relaying evolutionary roles in the polyploidization and speciation processes in the ginseng species complex.
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Affiliation(s)
- Ming-Rui Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Ning Ding
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Tianyuan Lu
- McGill University and Genome Quebec Innovation Center, Montreal, Quebec, Canada
| | - Jing Zhao
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Zhen-Hui Wang
- Faculty of Agronomy, Jilin Agricultural University, Changchun, China
| | - Peng Jiang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Si-Tong Liu
- School of Life Sciences, Jilin University, Changchun, China
| | - Xin-Feng Wang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Lin-Feng Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
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Till 2018: a survey of biomolecular sequences in genus Panax. J Ginseng Res 2020; 44:33-43. [PMID: 32095095 PMCID: PMC7033366 DOI: 10.1016/j.jgr.2019.06.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 06/07/2019] [Accepted: 06/12/2019] [Indexed: 12/22/2022] Open
Abstract
Ginseng is popularly known to be the king of ancient medicines and is used widely in most of the traditional medicinal compositions due to its various pharmaceutical properties. Numerous studies are being focused on this plant's curative effects to discover their potential health benefits in most human diseases, including cancer- the most life-threatening disease worldwide. Modern pharmacological research has focused mainly on ginsenosides, the major bioactive compounds of ginseng, because of their multiple therapeutic applications. Various issues on ginseng plant development, physiological processes, and agricultural issues have also been studied widely through state-of-the-art, high-throughput sequencing technologies. Since the beginning of the 21st century, the number of publications on ginseng has rapidly increased, with a recent count of more than 6,000 articles and reviews focusing notably on ginseng. Owing to the implementation of various technologies and continuous efforts, the ginseng plant genomes have been decoded effectively in recent years. Therefore, this review focuses mainly on the cellular biomolecular sequences in ginseng plants from the perspective of the central molecular dogma, with an emphasis on genomes, transcriptomes, and proteomes, together with a few other related studies.
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Li MR, Wang HY, Ding N, Lu T, Huang YC, Xiao HX, Liu B, Li LF. Rapid Divergence Followed by Adaptation to Contrasting Ecological Niches of Two Closely Related Columbine Species Aquilegia japonica and A. oxysepala. Genome Biol Evol 2019; 11:919-930. [PMID: 30793209 PMCID: PMC6433176 DOI: 10.1093/gbe/evz038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2019] [Indexed: 12/20/2022] Open
Abstract
Elucidating the mechanisms underlying the genetic divergence between closely related species is crucial to understanding the origin and evolution of biodiversity. The genus Aquilegia L. has undergone rapid adaptive radiation, generating about 70 well-recognized species that are specialized to distinct habitats and pollinators. In this study, to address the underlying evolutionary mechanisms that drive the genetic divergence, we analyzed the whole genomes of two ecologically isolated Aquilegia species, A. oxysepala and A. japonica as well as their putative hybrid. Our comparative genomic analyses reveal that while the two species diverged only recently and experienced recurrent gene flow, a high level of genetic divergence is observed in their nuclear genomes. In particular, candidate genomic regions that show signature of selection differ dramatically between the two species. Given that the splitting time of the two species is broadly matched with the decrease in effective population sizes, we propose that allopatric isolation together with natural selection have preceded the interspecific gene flow in the process of speciation. The observed high genetic divergence is likely an outcome of combined effects of natural selection, genetic drift and divergent sorting of ancestral polymorphisms. Our study provides a genome-wide view of how genetic divergence has evolved between closely related species.
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Affiliation(s)
- Ming-Rui Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Hua-Ying Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Ning Ding
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Tianyuan Lu
- McGill University and Genome Quebec Innovation Center, Montreal, Quebec, Canada
| | - Ye-Chao Huang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Hong-Xing Xiao
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun, China
| | - Lin-Feng Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
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Jiang P, Shi FX, Li MR, Liu B, Wen J, Xiao HX, Li LF. Positive Selection Driving Cytoplasmic Genome Evolution of the Medicinally Important Ginseng Plant Genus Panax. FRONTIERS IN PLANT SCIENCE 2018; 9:359. [PMID: 29670636 PMCID: PMC5893753 DOI: 10.3389/fpls.2018.00359] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Accepted: 03/05/2018] [Indexed: 05/30/2023]
Abstract
Panax L. (the ginseng genus) is a shade-demanding group within the family Araliaceae and all of its species are of crucial significance in traditional Chinese medicine. Phylogenetic and biogeographic analyses demonstrated that two rounds of whole genome duplications accompanying with geographic and ecological isolations promoted the diversification of Panax species. However, contributions of the cytoplasmic genomes to the adaptive evolution of Panax species remained largely uninvestigated. In this study, we sequenced the chloroplast and mitochondrial genomes of 11 accessions belonging to seven Panax species. Our results show that heterogeneity in nucleotide substitution rate is abundant in both of the two cytoplasmic genomes, with the mitochondrial genome possessing more variants at the total level but the chloroplast showing higher sequence polymorphisms at the genic regions. Genome-wide scanning of positive selection identified five and 12 genes from the chloroplast and mitochondrial genomes, respectively. Functional analyses further revealed that these selected genes play important roles in plant development, cellular metabolism and adaptation. We therefore conclude that positive selection might be one of the potential evolutionary forces that shaped nucleotide variation pattern of these Panax species. In particular, the mitochondrial genes evolved under stronger selective pressure compared to the chloroplast genes.
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Affiliation(s)
- Peng Jiang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
| | - Feng-Xue Shi
- Northeast Normal University Natural History Museum, Changchun, China
| | - Ming-Rui Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Bao Liu
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
| | - Jun Wen
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, United States
| | - Hong-Xing Xiao
- Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
| | - Lin-Feng Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Sciences, Fudan University, Shanghai, China
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