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Xie DF, Li J, Sun JH, Cheng RY, Wang Y, Song BN, He XJ, Zhou SD. Peering through the hedge: Multiple datasets yield insights into the phylogenetic relationships and incongruences in the tribe Lilieae (Liliaceae). Mol Phylogenet Evol 2024; 200:108182. [PMID: 39222738 DOI: 10.1016/j.ympev.2024.108182] [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: 11/09/2023] [Revised: 08/06/2024] [Accepted: 08/26/2024] [Indexed: 09/04/2024]
Abstract
The increasing use of genome-scale data has significantly facilitated phylogenetic analyses, contributing to the dissection of the underlying evolutionary mechanisms that shape phylogenetic incongruences, such as incomplete lineage sorting (ILS) and hybridization. Lilieae, a prominent member of the Liliaceae family, comprises four genera and approximately 260 species, representing 43% of all species within Liliaceae. They possess high ornamental, medicinal and edible values. Yet, no study has explored the validity of various genome-scale data in phylogenetic analyses within this tribe, nor have potential evolutionary mechanisms underlying its phylogenetic incongruences been investigated. Here, transcriptome, Angiosperms353, plastid and mitochondrial data, were collected from 50 to 93 samples of Lilieae, covering all four recognized genera. Multiple datasets were created and used for phylogenetic analyses based on concatenated and coalescent-based methods. Evolutionary rates of different datasets were calculated, and divergence times were estimated. Various approaches, including coalescence simulation, Quartet Sampling (QS), calculation of concordance factors (gCF and sCF), as well as MSCquartets and reticulate network inference, were carried out to infer the phylogenetic discordances and analyze their underlying mechanisms using a reduced 33-taxon dataset. Despite extensive phylogenetic discordances among gene trees, robust phylogenies were inferred from nuclear and plastid data compared to mitochondrial data, with lower synonymous substitution detected in mitochondrial genes than in nuclear and plastid genes. Significant ILS was detected across the phylogeny of Lilieae, with clear evidence of reticulate evolution identified. Divergence time estimation indicated that most of lineages in Lilieae diverged during a narrow time frame (ranging from 5.0 Ma to 10.0 Ma), consistent with the notion of rapid radiation evolution. Our results suggest that integrating transcriptomic and plastid data can serve as cost-effective and efficient tools for phylogenetic inference and evolutionary analysis within Lilieae, and Angiosperms353 data is also a favorable choice. Mitochondrial data are more suitable for phylogenetic analyses at higher taxonomic levels due to their stronger conservation and lower synonymous substitution rates. Significant phylogenetic incongruences detected in Lilieae were caused by both incomplete lineage sorting (ILS) and reticulate evolution, with hybridization and "ghost introgression" likely prevalent in the evolution of Lilieae species. Our findings provide new insights into the phylogeny of Lilieae, enhancing our understanding of the evolution of species in this tribe.
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Affiliation(s)
- Deng-Feng Xie
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, 610065 Chengdu, Sichuan, PR China.
| | - Juan Li
- Southwest Minzu University, Institute Of Qinghai-Tibetan Plateau, 610225 Chengdu, Sichuan, PR China
| | - Jia-Hui Sun
- State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, PR China
| | - Rui-Yu Cheng
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, 610065 Chengdu, Sichuan, PR China
| | - Yuan Wang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, 610065 Chengdu, Sichuan, PR China
| | - Bo-Ni Song
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, 610065 Chengdu, Sichuan, PR China
| | - Xing-Jin He
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, 610065 Chengdu, Sichuan, PR China
| | - Song-Dong Zhou
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, 610065 Chengdu, Sichuan, PR China.
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2
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Potter S, Moritz C, Piggott MP, Bragg JG, Afonso Silva AC, Bi K, McDonald-Spicer C, Turakulov R, Eldridge MDB. Museum Skins Enable Identification of Introgression Associated with Cytonuclear Discordance. Syst Biol 2024; 73:579-593. [PMID: 38577768 PMCID: PMC11377193 DOI: 10.1093/sysbio/syae016] [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: 03/10/2022] [Revised: 03/14/2024] [Accepted: 04/03/2024] [Indexed: 04/06/2024] Open
Abstract
Increased sampling of genomes and populations across closely related species has revealed that levels of genetic exchange during and after speciation are higher than previously thought. One obvious manifestation of such exchange is strong cytonuclear discordance, where the divergence in mitochondrial DNA (mtDNA) differs from that for nuclear genes more (or less) than expected from differences between mtDNA and nuclear DNA (nDNA) in population size and mutation rate. Given genome-scale data sets and coalescent modeling, we can now confidently identify cases of strong discordance and test specifically for historical or recent introgression as the cause. Using population sampling, combining exon capture data from historical museum specimens and recently collected tissues we showcase how genomic tools can resolve complex evolutionary histories in the brachyotis group of rock-wallabies (Petrogale). In particular, applying population and phylogenomic approaches we can assess the role of demographic processes in driving complex evolutionary patterns and assess a role of ancient introgression and hybridization. We find that described species are well supported as monophyletic taxa for nDNA genes, but not for mtDNA, with cytonuclear discordance involving at least 4 operational taxonomic units across 4 species which diverged 183-278 kya. ABC modeling of nDNA gene trees supports introgression during or after speciation for some taxon pairs with cytonuclear discordance. Given substantial differences in body size between the species involved, this evidence for gene flow is surprising. Heterogenous patterns of introgression were identified but do not appear to be associated with chromosome differences between species. These and previous results suggest that dynamic past climates across the monsoonal tropics could have promoted reticulation among related species.
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Affiliation(s)
- Sally Potter
- School of Natural Sciences, 14 Eastern Road, Macquarie University, Macquarie Park, NSW 2109, Australia
- Division of Ecology and Evolution, Research School of Biology, 134 Linnaeus Way, The Australian National University, Acton, ACT 2601, Australia
- Australian Museum Research Institute, Australian Museum, 1 William St, Sydney, NSW 2010, Australia
| | - Craig Moritz
- Division of Ecology and Evolution, Research School of Biology, 134 Linnaeus Way, The Australian National University, Acton, ACT 2601, Australia
| | - Maxine P Piggott
- Division of Ecology and Evolution, Research School of Biology, 134 Linnaeus Way, The Australian National University, Acton, ACT 2601, Australia
- Research Institute for the Environment and Livelihoods, Charles Darwin University, Casuarina, NT 0811, Australia
| | - Jason G Bragg
- National Herbarium of New South Wales, The Royal Botanical Gardens and Domain Trust, Mrs Macquaries Road, Sydney, NSW 2000, Australia
| | | | - Ke Bi
- Museum of Vertebrate Zoology and Department of Integrative Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Christiana McDonald-Spicer
- Division of Ecology and Evolution, Research School of Biology, 134 Linnaeus Way, The Australian National University, Acton, ACT 2601, Australia
| | - Rustamzhon Turakulov
- Australian Genome Research Facility, Victorian Comprehensive Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia
- Earth Sciences, College of Science and Engineering, Flinders University GPO Box 2100, Adelaide, SA 5001, Australia
| | - Mark D B Eldridge
- Australian Museum Research Institute, Australian Museum, 1 William St, Sydney, NSW 2010, Australia
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3
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Zhou J, Wang S, Yu S, Li Y, Qiao M, Zhao Q, Hughes E, Liu H, Bu W. Limits of mitochondrial genes in delimiting species within a Carbula species complex (Hemiptera: Pentatomidae). ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 115:e22075. [PMID: 38288487 DOI: 10.1002/arch.22075] [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: 05/29/2023] [Revised: 11/27/2023] [Accepted: 12/08/2023] [Indexed: 02/01/2024]
Abstract
Molecular data has become a powerful tool for species delimitation, particularly among those that present limited morphological differences; while the mitochondrial genome, with its moderate length, low cost of sequencing and fast lineage sorting, has emerged as a practical data set. Due to the limited morphological differences among the closely related species of Carbula Stål 1865, the species boundaries between Carbula abbreviata (Motschulsky, 1866), Carbula humerigera (Uhler, 1860), and Carbula putoni (Jakovlev, 1876) have remained particularly unclear. In this study, we applied two phylogenetic reconstruction methods to two data sets (mitogenome and COI) to assess the phylogeny of Carbula distributed in Asia, and five species delimitation methods to determine the boundaries between East Asian Carbula species. Our phylogenetic analyses showed Carbula to be paraphyletic; the seven known species distributed within East Asia to form a single monophyletic group, and within this, C. abbreviata, C. humerigera, C. putoni and middle-type to comprise a C. humerigera species complex. Our results show that mitogenome data alone, while effective in the differentiation of more distantly related Carbula species, is not sufficient to accurately delimit the species within this newly described complex.
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Affiliation(s)
- Jiayue Zhou
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, PR China
| | - Shujing Wang
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, PR China
| | - Shengjie Yu
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, PR China
| | - Yanfei Li
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, PR China
| | - Mu Qiao
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, PR China
| | - Qing Zhao
- College of Plant Protection, Shanxi Agricultural University, Taigu, PR China
| | | | - Huaxi Liu
- Department of Life Science, Natural History Museum, London, UK
| | - Wenjun Bu
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, PR China
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Tukhbatullin A, Ermakov O, Kapustina S, Starikov V, Tambovtseva V, Titov S, Brandler O. Surrounded by Kindred: Spermophilus major Hybridization with Other Spermophilus Species in Space and Time. BIOLOGY 2023; 12:880. [PMID: 37372163 DOI: 10.3390/biology12060880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/05/2023] [Accepted: 06/15/2023] [Indexed: 06/29/2023]
Abstract
Among the numerous described cases of hybridization in mammals, the most intriguing are (a) cases of introgressive hybridization deeply affecting the evolutionary history of species, and (b) models involving not a pair of species but a multi-species complex. Therefore, the hybridization history of the russet ground squirrel Spermophilus major, whose range has repeatedly changed due to climatic fluctuations and now borders the ranges of four related species, is of great interest. The main aims of this study were to determine the direction and intensity of gene introgression, the spatial depth of the infiltration of extraneous genes into the S. major range, and to refine the hypothesis of the hybridogenic replacement of mitochondrial genomes in the studied group. Using phylogenetic analysis of the variability of mitochondrial (CR, cytb) and nuclear (SmcY, BGN, PRKCI, c-myc, i6p53) markers, we determined the contribution of neighboring species to the S. major genome. We showed that 36% of S. major individuals had extraneous alleles. All peripheral species that were in contact with S. major contributed towards its genetic variability. We also proposed a hypothesis for the sequence and localization of serial hybridization events. Our assessment of the S. major genome implications of introgression highlights the importance of implementing conservation measures to protect this species.
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Affiliation(s)
- Andrey Tukhbatullin
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova Str. 26, Moscow 119334, Russia
| | - Oleg Ermakov
- Faculty of Physics, Mathematics and Natural Sciences, Belinsky Institute of Teacher Education, Penza State University, Lermontov Str. 37, Penza 440026, Russia
| | - Svetlana Kapustina
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova Str. 26, Moscow 119334, Russia
| | - Vladimir Starikov
- Department of Biology and Biotechnology, Institute of Natural and Technical Sciences, Surgut State University, Lenin Avenue 1, Surgut 628412, Russia
| | - Valentina Tambovtseva
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova Str. 26, Moscow 119334, Russia
| | - Sergey Titov
- Faculty of Physics, Mathematics and Natural Sciences, Belinsky Institute of Teacher Education, Penza State University, Lermontov Str. 37, Penza 440026, Russia
| | - Oleg Brandler
- Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova Str. 26, Moscow 119334, Russia
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5
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Ji J, Jackson DJ, Leaché AD, Yang Z. Power of Bayesian and Heuristic Tests to Detect Cross-Species Introgression with Reference to Gene Flow in the Tamias quadrivittatus Group of North American Chipmunks. Syst Biol 2023; 72:446-465. [PMID: 36504374 PMCID: PMC10275556 DOI: 10.1093/sysbio/syac077] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 11/15/2022] [Accepted: 12/01/2022] [Indexed: 10/25/2023] Open
Abstract
In the past two decades, genomic data have been widely used to detect historical gene flow between species in a variety of plants and animals. The Tamias quadrivittatus group of North America chipmunks, which originated through a series of rapid speciation events, are known to undergo massive amounts of mitochondrial introgression. Yet in a recent analysis of targeted nuclear loci from the group, no evidence for cross-species introgression was detected, indicating widespread cytonuclear discordance. The study used the heuristic method HYDE to detect gene flow, which may suffer from low power. Here we use the Bayesian method implemented in the program BPP to re-analyze these data. We develop a Bayesian test of introgression, calculating the Bayes factor via the Savage-Dickey density ratio using the Markov chain Monte Carlo (MCMC) sample under the model of introgression. We take a stepwise approach to constructing an introgression model by adding introgression events onto a well-supported binary species tree. The analysis detected robust evidence for multiple ancient introgression events affecting the nuclear genome, with introgression probabilities reaching 63%. We estimate population parameters and highlight the fact that species divergence times may be seriously underestimated if ancient cross-species gene flow is ignored in the analysis. We examine the assumptions and performance of HYDE and demonstrate that it lacks power if gene flow occurs between sister lineages or if the mode of gene flow does not match the assumed hybrid-speciation model with symmetrical population sizes. Our analyses highlight the power of likelihood-based inference of cross-species gene flow using genomic sequence data. [Bayesian test; BPP; chipmunks; introgression; MSci; multispecies coalescent; Savage-Dickey density ratio.].
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Affiliation(s)
- Jiayi Ji
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - Donavan J Jackson
- Department of Biology and Burke Museum of Natural History and Culture, University of Washington, Box 351800, Seattle, WA 98195-1800, USA
| | - Adam D Leaché
- Department of Biology and Burke Museum of Natural History and Culture, University of Washington, Box 351800, Seattle, WA 98195-1800, USA
| | - Ziheng Yang
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
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6
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Maternal Donor and Genetic Variation of Lagerstroemia indica Cultivars. Int J Mol Sci 2023; 24:ijms24043606. [PMID: 36835020 PMCID: PMC9964644 DOI: 10.3390/ijms24043606] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/30/2022] [Accepted: 02/08/2023] [Indexed: 02/16/2023] Open
Abstract
Lagerstroemia indica L. is a well-known ornamental plant with large pyramidal racemes, long flower duration, and diverse colors and cultivars. It has been cultivated for nearly 1600 years and is essential for investigating the germplasm and assessing genetic variation to support international cultivar identification and breeding programs. In this study, 20 common Lagerstroemia indica cultivars from different varietal groups and flower morphologies, as well as multiple wild relative species, were analyzed to investigate the maternal donor of Lagerstroemia indica cultivars and to discover the genetic variation and relationships among cultivars based on plastome and nuclear ribosomal DNA (nrDNA) sequences. A total of 47 single nucleotide polymorphisms (SNPs) and 24 insertion/deletions (indels) were identified in the 20 L. indica cultivars' plastome and 25 SNPs were identified in the nrDNA. Phylogenetic analysis based on the plastome sequences showed that all the cultivars formed a clade with the species of L. indica, indicating that L. indica was the maternal donor of the cultivars. Population structure and PCA analyses supported two clades of cultivars, which exhibited significant genetic differences according to the plastome dataset. The results of the nrDNA supported that all 20 cultivars were divided into three clades and most of the cultivars had at least two genetic backgrounds and higher gene flow. Our results suggest that the plastome and nrDNA sequences can be used as molecular markers for assessing the genetic variation and relationships of L. indica cultivars.
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Herrera ND, Bell KC, Callahan CM, Nordquist E, Sarver BAJ, Sullivan J, Demboski JR, Good JM. Genomic resolution of cryptic species diversity in chipmunks. Evolution 2022; 76:2004-2019. [PMID: 35778920 DOI: 10.1111/evo.14546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 06/01/2022] [Accepted: 06/06/2022] [Indexed: 01/22/2023]
Abstract
Discovery of cryptic species is essential to understand the process of speciation and assessing the impacts of anthropogenic stressors. Here, we used genomic data to test for cryptic species diversity within an ecologically well-known radiation of North American rodents, western chipmunks (Tamias). We assembled a de novo reference genome for a single species (Tamias minimus) combined with new and published targeted sequence-capture data for 21,551 autosomal and 493 X-linked loci sampled from 121 individuals spanning 22 species. We identified at least two cryptic lineages corresponding with an isolated subspecies of least chipmunk (T. minimus grisescens) and with a restricted subspecies of the yellow-pine chipmunk (Tamias amoenus cratericus) known only from around the extensive Craters of the Moon lava flow. Additional population-level sequence data revealed that the so-called Crater chipmunk is a distinct species that is abundant throughout the coniferous forests of southern Idaho. This cryptic lineage does not appear to be most closely related to the ecologically and phenotypically similar yellow-pine chipmunk but does show evidence for recurrent hybridization with this and other species.
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Affiliation(s)
- Nathanael D Herrera
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Kayce C Bell
- Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - Colin M Callahan
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Erin Nordquist
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Brice A J Sarver
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Jack Sullivan
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, USA.,Institute for Bioinformatics and Evolutionary Studies (IBEST), University of Idaho, Moscow, Idaho, USA
| | - John R Demboski
- Department of Zoology, Denver Museum of Nature & Sciences, Denver, Colorado, USA
| | - Jeffrey M Good
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA.,Wildlife Biology Program, University of Montana, Missoula, Montana, USA
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Kao T, Wang T, Ku C. Rampant nuclear-mitochondrial-plastid phylogenomic discordance in globally distributed calcifying microalgae. THE NEW PHYTOLOGIST 2022; 235:1394-1408. [PMID: 35556250 PMCID: PMC9539906 DOI: 10.1111/nph.18219] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
Incongruent phylogenies have been widely observed between nuclear and plastid or mitochondrial genomes in terrestrial plants and animals. However, few studies have examined these patterns in microalgae or the discordance between the two organelles. Here we investigated the nuclear-mitochondrial-plastid phylogenomic incongruence in Emiliania-Gephyrocapsa, a group of cosmopolitan calcifying phytoplankton with enormous populations and recent speciations. We assembled mitochondrial and plastid genomes of 27 strains from across global oceans and temperature regimes, and analyzed the phylogenomic histories of the three compartments using concatenation and coalescence methods. Six major clades with varying morphology and distribution are well recognized in the nuclear phylogeny, but such relationships are absent in the mitochondrial and plastid phylogenies, which also differ substantially from each other. The rampant phylogenomic discordance is due to a combination of organellar capture (introgression), organellar genome recombination, and incomplete lineage sorting of ancient polymorphic organellar genomes. Hybridization can lead to replacements of whole organellar genomes without introgression of nuclear genes and the two organelles are not inherited as a single cytoplasmic unit. This study illustrates the convoluted evolution and inheritance of organellar genomes in isogamous haplodiplontic microalgae and provides a window into the phylogenomic complexity of marine unicellular eukaryotes.
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Affiliation(s)
- Tzu‐Tong Kao
- Institute of Plant and Microbial BiologyAcademia SinicaTaipei11529Taiwan
| | - Tzu‐Haw Wang
- Institute of Plant and Microbial BiologyAcademia SinicaTaipei11529Taiwan
| | - Chuan Ku
- Institute of Plant and Microbial BiologyAcademia SinicaTaipei11529Taiwan
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Yang Z, Flouri T. Estimation of Cross-Species Introgression Rates Using Genomic Data Despite Model Unidentifiability. Mol Biol Evol 2022; 39:msac083. [PMID: 35417543 PMCID: PMC9087891 DOI: 10.1093/molbev/msac083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Full-likelihood implementations of the multispecies coalescent with introgression (MSci) model treat genealogical fluctuations across the genome as a major source of information to infer the history of species divergence and gene flow using multilocus sequence data. However, MSci models are known to have unidentifiability issues, whereby different models or parameters make the same predictions about the data and cannot be distinguished by the data. Previous studies of unidentifiability have focused on heuristic methods based on gene trees and do not make an efficient use of the information in the data. Here we study the unidentifiability of MSci models under the full-likelihood methods. We characterize the unidentifiability of the bidirectional introgression (BDI) model, which assumes that gene flow occurs in both directions. We derive simple rules for arbitrary BDI models, which create unidentifiability of the label-switching type. In general, an MSci model with k BDI events has 2k unidentifiable modes or towers in the posterior, with each BDI event between sister species creating within-model parameter unidentifiability and each BDI event between nonsister species creating between-model unidentifiability. We develop novel algorithms for processing Markov chain Monte Carlo samples to remove label-switching problems and implement them in the bpp program. We analyze real and synthetic data to illustrate the utility of the BDI models and the new algorithms. We discuss the unidentifiability of heuristic methods and provide guidelines for the use of MSci models to infer gene flow using genomic data.
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Affiliation(s)
- Ziheng Yang
- Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK
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10
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UCE sequencing-derived mitogenomes reveal the timing of mitochondrial replacement in Malagasy shrew tenrecs (Afrosoricida, Tenrecidae, Microgale). Mamm Biol 2022. [DOI: 10.1007/s42991-022-00246-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AbstractMalagasy shrew tenrecs (Microgale) have increasingly been used to study speciation genetics over the last years. A previous study recently uncovered gene flow between the Shrew-toothed shrew tenrec (M. soricoides) and sympatric southern population of the Pale shrew tenrec (M. fotsifotsy). This gene flow has been suggested to be accompanied by complete mitochondrial replacement in M. fotsifotsy. To explore the temporal framework of this replacement, we assembled mitogenomes from publicly available sequencing data of ultra-conserved elements. We were able to assemble complete and partial mitogenomes for 19 specimens from five species of shrew tenrecs, which represents a multifold increase in mitogenomic resources available for all tenrecs. Phylogenetic inferences and sequence simulations support the close relationship between the mitochondrial lineages of M. soricoides and the southern population of M. fotsifotsy. Based on the nuclear divergence of northern and southern populations of M. fotsifotsy and the mitochondrial divergence between the latter and M. soricoides, there was a mean time window for replacement of ~ 350,000 years. This timeframe implies that the effective size of the ancestral M. fotsifotsy southern population was less 70,000.
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11
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McLean BS, Bell KC, Cook JA. SNP-based Phylogenomic Inference in Holarctic Ground Squirrels (Urocitellus). Mol Phylogenet Evol 2022; 169:107396. [PMID: 35031463 DOI: 10.1016/j.ympev.2022.107396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 12/02/2021] [Accepted: 12/08/2021] [Indexed: 11/24/2022]
Abstract
Resolution of rapid evolutionary radiations requires harvesting maximal signal from phylogenomic datasets. However, studies of non-model clades often target conserved loci that are characterized by reduced information content, which can negatively affect gene tree precision and species tree accuracy. Single nucleotide polymorphism (SNP)-based methods are an underutilized but potentially valuable tool for estimating phylogeny and divergence times because they do not rely on resolved gene trees, allowing information from many or all variant loci to be leveraged in species tree reconstruction. We evaluated the utility of SNP-based methods in resolving phylogeny of Holarctic ground squirrels (Urocitellus), a radiation that has been difficult to disentangle, even in prior phylogenomic studies. We inferred phylogeny from a dataset of >3,000 ultraconserved element loci (UCEs) using two methods (SNAPP, SVDquartets) and compared our results with a new mitogenome phylogeny. We also systematically evaluated how phasing of UCEs improves per-locus information content, and inference of topology and other parameters within each of these SNP-based methods. Phasing improved topological resolution and branch length estimation at shallow levels (within species complexes), but less so at deeper levels, likely reflecting true uncertainty due to ancestral polymorphisms segregating in these rapidly diverging lineages. We resolved several key clades in Urocitellus and present targeted opportunities for future phylogenomic inquiry. Our results extend the roadmap for use of SNPs to address vertebrate radiations and support comparative analyses at multiple temporal scales.
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Affiliation(s)
- Bryan S McLean
- University of North Carolina Greensboro, Department of Biology, Greensboro, NC 27402 USA.
| | - Kayce C Bell
- Natural History Museum of Los Angeles County, Department of Mammalogy, Los Angeles, CA 90007 USA.
| | - Joseph A Cook
- University of New Mexico, Department of Biology and Museum of Southwestern Biology, Albuquerque, NM 87131 USA.
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12
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Adavoudi R, Pilot M. Consequences of Hybridization in Mammals: A Systematic Review. Genes (Basel) 2021; 13:50. [PMID: 35052393 PMCID: PMC8774782 DOI: 10.3390/genes13010050] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/14/2021] [Accepted: 12/20/2021] [Indexed: 12/18/2022] Open
Abstract
Hybridization, defined as breeding between two distinct taxonomic units, can have an important effect on the evolutionary patterns in cross-breeding taxa. Although interspecific hybridization has frequently been considered as a maladaptive process, which threatens species genetic integrity and survival via genetic swamping and outbreeding depression, in some cases hybridization can introduce novel adaptive variation and increase fitness. Most studies to date focused on documenting hybridization events and analyzing their causes, while relatively little is known about the consequences of hybridization and its impact on the parental species. To address this knowledge gap, we conducted a systematic review of studies on hybridization in mammals published in 2010-2021, and identified 115 relevant studies. Of 13 categories of hybridization consequences described in these studies, the most common negative consequence (21% of studies) was genetic swamping and the most common positive consequence (8%) was the gain of novel adaptive variation. The total frequency of negative consequences (49%) was higher than positive (13%) and neutral (38%) consequences. These frequencies are biased by the detection possibilities of microsatellite loci, the most common genetic markers used in the papers assessed. As negative outcomes are typically easier to demonstrate than positive ones (e.g., extinction vs hybrid speciation), they may be over-represented in publications. Transition towards genomic studies involving both neutral and adaptive variation will provide a better insight into the real impacts of hybridization.
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Affiliation(s)
| | - Małgorzata Pilot
- Museum and Institute of Zoology, Polish Academy of Sciences, ul. Nadwiślańska 108, 80-680 Gdańsk, Poland;
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13
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Nickel J, Schell T, Holtzem T, Thielsch A, Dennis SR, Schlick-Steiner BC, Steiner FM, Möst M, Pfenninger M, Schwenk K, Cordellier M. Hybridization Dynamics and Extensive Introgression in the Daphnia longispina Species Complex: New Insights from a High-Quality Daphnia galeata Reference Genome. Genome Biol Evol 2021; 13:6448229. [PMID: 34865004 PMCID: PMC8695838 DOI: 10.1093/gbe/evab267] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2021] [Indexed: 01/02/2023] Open
Abstract
Hybridization and introgression are recognized as an important source of variation that influence adaptive processes; both phenomena are frequent in the genus Daphnia, a keystone zooplankton taxon in freshwater ecosystems that comprises several species complexes. To investigate genome-wide consequences of introgression between species, we provide here the first high-quality genome assembly for a member of the Daphnia longispina species complex, Daphnia galeata. We further resequenced 49 whole genomes of three species of the complex and their interspecific hybrids both from genotypes sampled in the water column and from single resting eggs extracted from sediment cores. Populations from habitats with diverse ecological conditions offered an opportunity to study the dynamics of hybridization linked to ecological changes and revealed a high prevalence of hybrids. Using phylogenetic and population genomic approaches, we provide first insights into the intra- and interspecific genome-wide variability in this species complex and identify regions of high divergence. Finally, we assess the length of ancestry tracts in hybrids to characterize introgression patterns across the genome. Our analyses uncover a complex history of hybridization and introgression reflecting multiple generations of hybridization and backcrossing in the Daphnia longispina species complex. Overall, this study and the new resources presented here pave the way for a better understanding of ancient and contemporary gene flow in the species complex and facilitate future studies on resting egg banks accumulating in lake sediment.
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Affiliation(s)
- Jana Nickel
- Institute of Zoology, Universität Hamburg, Germany
| | - Tilman Schell
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt am Main, Germany
| | - Tania Holtzem
- Department of Ecology, University of Innsbruck, Austria
| | - Anne Thielsch
- Molecular Ecology, Institute for Environmental Sciences, University Koblenz-Landau, Landau in der Pfalz, Germany
| | - Stuart R Dennis
- Department of Aquatic Ecology, EAWAG, Dübendorf, Switzerland
| | | | | | - Markus Möst
- Department of Ecology, University of Innsbruck, Austria
| | - Markus Pfenninger
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt am Main, Germany.,Molecular Ecology, Senckenberg Biodiversity and Climate Research Centre, Frankfurt, Germany.,IoME, Gutenberg University, Mainz, Germany
| | - Klaus Schwenk
- Molecular Ecology, Institute for Environmental Sciences, University Koblenz-Landau, Landau in der Pfalz, Germany
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14
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Nagorsen DW, Panter N, Copley D. Phenotypes and Distribution of Yellow-Pine Chipmunk (Neotamias amoenus) of Hybrid Ancestry from the Rocky Mountains of Canada. WEST N AM NATURALIST 2021. [DOI: 10.3398/064.081.0303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- David W. Nagorsen
- Royal British Columbia Museum, 675 Bellville Street, Victoria, BC V8W 9W2, Canada
| | - Nick Panter
- Royal British Columbia Museum, 675 Bellville Street, Victoria, BC V8W 9W2, Canada
| | - Darren Copley
- Royal British Columbia Museum, 675 Bellville Street, Victoria, BC V8W 9W2, Canada
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15
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Mitonuclear mismatch alters nuclear gene expression in naturally introgressed Rhinolophus bats. Front Zool 2021; 18:42. [PMID: 34488775 PMCID: PMC8419968 DOI: 10.1186/s12983-021-00424-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/20/2021] [Indexed: 01/23/2023] Open
Abstract
Background Mitochondrial function involves the interplay between mitochondrial and nuclear genomes. Such mitonuclear interactions can be disrupted by the introgression of mitochondrial DNA between taxa or divergent populations. Previous studies of several model systems (e.g. Drosophila) indicate that the disruption of mitonuclear interactions, termed mitonuclear mismatch, can alter nuclear gene expression, yet few studies have focused on natural populations. Results Here we study a naturally introgressed population in the secondary contact zone of two subspecies of the intermediate horseshoe bat (Rhinolophus affinis), in which individuals possess either mitonuclear matched or mismatched genotypes. We generated transcriptome data for six tissue types from five mitonuclear matched and five mismatched individuals. Our results revealed strong tissue-specific effects of mitonuclear mismatch on nuclear gene expression with the largest effect seen in pectoral muscle. Moreover, consistent with the hypothesis that genes associated with the response to oxidative stress may be upregulated in mitonuclear mismatched individuals, we identified several such gene candidates, including DNASE1L3, GPx3 and HSPB6 in muscle, and ISG15 and IFI6 in heart. Conclusion Our study reveals how mitonuclear mismatch arising from introgression in natural populations is likely to have fitness consequences. Underlying the processes that maintain mitonuclear discordance is a step forward to understand the role of mitonuclear interactions in population divergence and speciation. Supplementary Information The online version contains supplementary material available at 10.1186/s12983-021-00424-x.
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16
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Huang J, Bennett J, Flouri T, Leaché AD, Yang Z. Phase Resolution of Heterozygous Sites in Diploid Genomes is Important to Phylogenomic Analysis under the Multispecies Coalescent Model. Syst Biol 2021; 71:334-352. [PMID: 34143216 PMCID: PMC8977997 DOI: 10.1093/sysbio/syab047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 06/03/2021] [Accepted: 06/21/2021] [Indexed: 01/01/2023] Open
Abstract
Genome sequencing projects routinely generate haploid consensus sequences from diploid
genomes, which are effectively chimeric sequences with the phase at heterozygous sites
resolved at random. The impact of phasing errors on phylogenomic analyses under the
multispecies coalescent (MSC) model is largely unknown. Here, we conduct a computer
simulation to evaluate the performance of four phase-resolution strategies (the true phase
resolution, the diploid analytical integration algorithm which averages over all phase
resolutions, computational phase resolution using the program PHASE, and random
resolution) on estimation of the species tree and evolutionary parameters in analysis of
multilocus genomic data under the MSC model. We found that species tree estimation is
robust to phasing errors when species divergences were much older than average coalescent
times but may be affected by phasing errors when the species tree is shallow. Estimation
of parameters under the MSC model with and without introgression is affected by phasing
errors. In particular, random phase resolution causes serious overestimation of population
sizes for modern species and biased estimation of cross-species introgression probability.
In general, the impact of phasing errors is greater when the mutation rate is higher, the
data include more samples per species, and the species tree is shallower with recent
divergences. Use of phased sequences inferred by the PHASE program produced small biases
in parameter estimates. We analyze two real data sets, one of East Asian brown frogs and
another of Rocky Mountains chipmunks, to demonstrate that heterozygote phase-resolution
strategies have similar impacts on practical data analyses. We suggest that genome
sequencing projects should produce unphased diploid genotype sequences if fully phased
data are too challenging to generate, and avoid haploid consensus sequences, which have
heterozygous sites phased at random. In case the analytical integration algorithm is
computationally unfeasible, computational phasing prior to population genomic analyses is
an acceptable alternative. [BPP; introgression; multispecies coalescent; phase; species
tree.]
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Affiliation(s)
- Jun Huang
- Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK.,Department of Mathematics, Beijing Jiaotong University, Beijing, 100044, P.R. China
| | - Jeremy Bennett
- Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK.,Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, Unit 3043, Storrs, CT 06269-3043, USA
| | - Tomáš Flouri
- Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK
| | - Adam D Leaché
- Department of Biology & Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195-1800, USA
| | - Ziheng Yang
- Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK
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