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Steenwyk JL, Li Y, Zhou X, Shen XX, Rokas A. Incongruence in the phylogenomics era. Nat Rev Genet 2023; 24:834-850. [PMID: 37369847 DOI: 10.1038/s41576-023-00620-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2023] [Indexed: 06/29/2023]
Abstract
Genome-scale data and the development of novel statistical phylogenetic approaches have greatly aided the reconstruction of a broad sketch of the tree of life and resolved many of its branches. However, incongruence - the inference of conflicting evolutionary histories - remains pervasive in phylogenomic data, hampering our ability to reconstruct and interpret the tree of life. Biological factors, such as incomplete lineage sorting, horizontal gene transfer, hybridization, introgression, recombination and convergent molecular evolution, can lead to gene phylogenies that differ from the species tree. In addition, analytical factors, including stochastic, systematic and treatment errors, can drive incongruence. Here, we review these factors, discuss methodological advances to identify and handle incongruence, and highlight avenues for future research.
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Affiliation(s)
- Jacob L Steenwyk
- Howards Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Evolutionary Studies Initiative, Vanderbilt University, Nashville, TN, USA
| | - Yuanning Li
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
| | - Xiaofan Zhou
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Xing-Xing Shen
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA.
- Vanderbilt Evolutionary Studies Initiative, Vanderbilt University, Nashville, TN, USA.
- Heidelberg Institute for Theoretical Studies, Heidelberg, Germany.
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2
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Ranade SS, García-Gil MR. Clinal variation in PHY (PAS domain) and CRY (CCT domain)-Signs of local adaptation to light quality in Norway spruce. PLANT, CELL & ENVIRONMENT 2023. [PMID: 37291974 DOI: 10.1111/pce.14638] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 05/19/2023] [Accepted: 05/25/2023] [Indexed: 06/10/2023]
Abstract
Detection of the genomic basis of local adaptation to environmental conditions is challenging in forest trees. Phytochromes (PHY) and cryptochromes (CRY) perceive the red (R)/far-red (FR) and blue light respectively, thus playing a fundamental role in regulating plant growth and development. PHYO and PHYP from conifers are the equivalents of PHYA/PHYC and PHYB in angiosperms, respectively. Norway spruce shows an adaptive latitudinal cline for shade (low R:FR or FR-enriched light) tolerance and requirement of FR light for its growth. We analyzed the exome capture data that included a uniquely large data set of 1654 Norway spruce trees sampled across many latitudes in Sweden to capture the natural clines for photoperiod and FR light exposure during the growth season. Statistically significant clinal variation was detected in allele and genotype frequencies of missense mutations in coding regions belonging to well-defined functional domains of PHYO (PAS-B), PHYP2 (PAS fold-2), CRY1 (CCT1) and CRY2 (CCT2) that strongly correlates with the latitudinal gradient in response to variable light quality in Norway spruce. The missense SNP in PHYO resulting in Asn835Ser, displayed the steepest cline among all other polymorphisms. We propose that these variations in the photoreceptors represent signs of local adaptation to light quality.
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Affiliation(s)
- Sonali Sachin Ranade
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - María Rosario García-Gil
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, Umeå, Sweden
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3
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Scutt CP. Model Species to Investigate the Origin of Flowers. Methods Mol Biol 2023; 2686:83-109. [PMID: 37540355 DOI: 10.1007/978-1-0716-3299-4_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
The angiosperms, or flowering plants, arose at least 135 million years ago (Ma) and rapidly diversified to form over 300,000 species alive today. This group appears, however, to have separated from its closest living relatives, the extant gymnosperms, much earlier: over 300 Ma. Representatives of basally-diverging angiosperm lineages are of key importance to studies aimed at reconstructing the most recent common ancestor of living angiosperms, including its morphological, anatomical, eco-physiological and molecular aspects. Furthermore, evo-devo comparisons of angiosperms with living gymnosperms may help to determine how the many novel aspects of angiosperms, including those of the flower, first came about. This chapter reviews literature on the origin of angiosperms and focusses on basally-diverging angiosperms and gymnosperms that show advantages as potential experimental models, reviewing information and protocols for the use of these species in an evo-devo context. The final section suggests a means by which data from living and fossil groups could be integrated to better elucidate evolutionary events that took place on the long stem-lineage that apparently preceded the radiation of living angiosperms.
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Affiliation(s)
- Charles P Scutt
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon-1, CNRS, INRA, Lyon, France.
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4
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Tseng ZJ, Wang X, Li Q, Xie G. Qurliqnoria (Mammalia: Bovidae) fossils from Qaidam Basin, Tibetan Plateau and deep-time endemism of the Tibetan antelope lineage. Zool J Linn Soc 2022. [DOI: 10.1093/zoolinnean/zlab117] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
The Tibetan antelope (Pantholops hodgsonii) is an endemic bovid of the Tibetan Plateau, which was, until recently, considered an endangered species. Researchers have long speculated on the evolutionary origin of Pantholops, suggesting a connection to the rare fossil bovid Qurliqnoria. However, the lack of adequate fossil samples has prevented the testing of this deep-time endemism hypothesis for eight decades. Here, we report new fossils of Qurliqnoria cheni from the northern Tibetan Plateau, substantially increasing the amount of morphological data that can be brought to bear on the question of Tibetan antelope evolution. Phylogenetic analysis supports a Pantholops–Qurliqnoria clade and suggests that this lineage has been endemic to the Plateau for 11 Myr. Recent morphological and molecular studies that support the outgroup position of Pantholops relative to caprins (goats and relatives) and the fossil record of stem bovids from Europe together suggest that the Qurliqnoria–Pantholops lineage is likely to have dispersed to the Tibetan Plateau 15–11 Mya. Furthermore, the harsh environmental conditions to which Pantholops has adapted are likely to extend back to the time of its evolutionary origin. These findings provide an important new context for conservation management and research into the near-threatened Tibetan antelope, as the longest-living endemic member of the Tibetan Plateau fauna.
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Affiliation(s)
- Z Jack Tseng
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA 94720, California, USA
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, California, USA
| | - Xiaoming Wang
- Department of Vertebrate Paleontology, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, California, USA
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijng 100044, China
| | - Qiang Li
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijng 100044, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guangpu Xie
- Natural Science Department, Gansu Provincial Museum, No. 3 Xijingxi Road, Lanzhou 730050, Gansu, China
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5
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Mascotti ML. Resurrecting Enzymes by Ancestral Sequence Reconstruction. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2397:111-136. [PMID: 34813062 DOI: 10.1007/978-1-0716-1826-4_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Ancestral Sequence Reconstruction (ASR) allows one to infer the sequences of extinct proteins using the phylogeny of extant proteins. It consists of disclosing the evolutionary history-i.e., the phylogeny-of a protein family of interest and then inferring the sequences of its ancestors-i.e., the nodes in the phylogeny. Assisted by gene synthesis, the selected ancestors can be resurrected in the lab and experimentally characterized. The crucial step to succeed with ASR is starting from a reliable phylogeny. At the same time, it is of the utmost importance to have a clear idea on the evolutionary history of the family under study and the events that influenced it. This allows us to implement ASR with well-defined hypotheses and to apply the appropriate experimental methods. In the last years, ASR has become popular to test hypotheses about the origin of functionalities, changes in activities, understanding physicochemical properties of proteins, among others. In this context, the aim of this chapter is to present the ASR approach applied to the reconstruction of enzymes-i.e., proteins with catalytic roles. The spirit of this contribution is to provide a basic, hands-to-work guide for biochemists and biologists who are unfamiliar with molecular phylogenetics.
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Affiliation(s)
- Maria Laura Mascotti
- Molecular Enzymology group, University of Groningen, Groningen, The Netherlands. .,IMIBIO-SL CONICET, Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina.
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6
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Yuan C, Sha X, Xiong M, Zhong W, Wei Y, Li M, Tao S, Mou F, Peng F, Zhang C. Uncovering dynamic evolution in the plastid genome of seven Ligusticum species provides insights into species discrimination and phylogenetic implications. Sci Rep 2021; 11:988. [PMID: 33441833 PMCID: PMC7806627 DOI: 10.1038/s41598-020-80225-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 12/16/2020] [Indexed: 12/02/2022] Open
Abstract
Ligusticum L., one of the largest members in Apiaceae, encompasses medicinally important plants, the taxonomic statuses of which have been proved to be difficult to resolve. In the current study, the complete chloroplast genomes of seven crucial plants of the best-known herbs in Ligusticum were presented. The seven genomes ranged from 148,275 to 148,564 bp in length with a highly conserved gene content, gene order and genomic arrangement. A shared dramatic decrease in genome size resulted from a lineage-specific inverted repeat (IR) contraction, which could potentially be a promising diagnostic character for taxonomic investigation of Ligusticum, was discovered, without affecting the synonymous rate. Although a higher variability was uncovered in hotspot divergence regions that were unevenly distributed across the chloroplast genome, a concatenated strategy for rapid species identification was proposed because separate fragments inadequately provided variation for fine resolution. Phylogenetic inference using plastid genome-scale data produced a concordant topology receiving a robust support value, which revealed that L. chuanxiong had a closer relationship with L. jeholense than L. sinense, and L. sinense cv. Fuxiong had a closer relationship to L. sinense than L. chuanxiong, for the first time. Our results not only furnish concrete evidence for clarifying Ligusticum taxonomy but also provide a solid foundation for further pharmaphylogenetic investigation.
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Affiliation(s)
- Can Yuan
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China.,Comprehensive Experimental Station of Cheng Du, Chinese Materia Medica of China Agriculture Research System, Chengdu, 610300, China
| | - Xiufen Sha
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China.,Comprehensive Experimental Station of Cheng Du, Chinese Materia Medica of China Agriculture Research System, Chengdu, 610300, China
| | - Miao Xiong
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China.,Comprehensive Experimental Station of Cheng Du, Chinese Materia Medica of China Agriculture Research System, Chengdu, 610300, China
| | - Wenjuan Zhong
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China.,Comprehensive Experimental Station of Cheng Du, Chinese Materia Medica of China Agriculture Research System, Chengdu, 610300, China
| | - Yu Wei
- National Key Facility for Crop Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Mingqian Li
- Cancer Institute of Integrated Traditional Chinese and Western Medicine, Zhejiang Academy of Traditional Chinese Medicine, Tongde Hospital of Zhejiang Province, Hangzhou, 310012, Zhejiang, China
| | - Shan Tao
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China.,Comprehensive Experimental Station of Cheng Du, Chinese Materia Medica of China Agriculture Research System, Chengdu, 610300, China
| | - Fangsheng Mou
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China
| | - Fang Peng
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China. .,Comprehensive Experimental Station of Cheng Du, Chinese Materia Medica of China Agriculture Research System, Chengdu, 610300, China.
| | - Chao Zhang
- Industrial Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610300, China. .,Comprehensive Experimental Station of Cheng Du, Chinese Materia Medica of China Agriculture Research System, Chengdu, 610300, China.
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7
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Roa-Varón A, Dikow RB, Carnevale G, Tornabene L, Baldwin CC, Li C, Hilton EJ. Confronting Sources of Systematic Error to Resolve Historically Contentious Relationships: A Case Study Using Gadiform Fishes (Teleostei, Paracanthopterygii, Gadiformes). Syst Biol 2020; 70:739-755. [PMID: 33346841 PMCID: PMC8561434 DOI: 10.1093/sysbio/syaa095] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 11/27/2020] [Accepted: 12/02/2020] [Indexed: 11/14/2022] Open
Abstract
Reliable estimation of phylogeny is central to avoid inaccuracy in downstream macroevolutionary inferences. However, limitations exist in the implementation of concatenated and summary coalescent approaches, and Bayesian and full coalescent inference methods may not yet be feasible for computation of phylogeny using complicated models and large data sets. Here, we explored methodological (e.g., optimality criteria, character sampling, model selection) and biological (e.g., heterotachy, branch length heterogeneity) sources of systematic error that can result in biased or incorrect parameter estimates when reconstructing phylogeny by using the gadiform fishes as a model clade. Gadiformes include some of the most economically important fishes in the world (e.g., Cods, Hakes, and Rattails). Despite many attempts, a robust higher-level phylogenetic framework was lacking due to limited character and taxonomic sampling, particularly from several species-poor families that have been recalcitrant to phylogenetic placement. We compiled the first phylogenomic data set, including 14,208 loci (\documentclass[12pt]{minimal}
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}{}$>$\end{document}2.8 M bp) from 58 species representing all recognized gadiform families, to infer a time-calibrated phylogeny for the group. Data were generated with a gene-capture approach targeting coding DNA sequences from single-copy protein-coding genes. Species-tree and concatenated maximum-likelihood (ML) analyses resolved all family-level relationships within Gadiformes. While there were a few differences between topologies produced by the DNA and the amino acid data sets, most of the historically unresolved relationships among gadiform lineages were consistently well resolved with high support in our analyses regardless of the methodological and biological approaches used. However, at deeper levels, we observed inconsistency in branch support estimates between bootstrap and gene and site coefficient factors (gCF, sCF). Despite numerous short internodes, all relationships received unequivocal bootstrap support while gCF and sCF had very little support, reflecting hidden conflict across loci. Most of the gene-tree and species-tree discordance in our study is a result of short divergence times, and consequent lack of informative characters at deep levels, rather than incomplete lineage sorting. We use this phylogeny to establish a new higher-level classification of Gadiformes as a way of clarifying the evolutionary diversification of the order. We recognize 17 families in five suborders: Bregmacerotoidei, Gadoidei, Ranicipitoidei, Merluccioidei, and Macrouroidei (including two subclades). A time-calibrated analysis using 15 fossil taxa suggests that Gadiformes evolved \documentclass[12pt]{minimal}
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}{}$\sim $\end{document}79.5 Ma in the late Cretaceous, but that most extant lineages diverged after the Cretaceous–Paleogene (K-Pg) mass extinction (66 Ma). Our results reiterate the importance of examining phylogenomic analyses for evidence of systematic error that can emerge as a result of unsuitable modeling of biological factors and/or methodological issues, even when data sets are large and yield high support for phylogenetic relationships. [Branch length heterogeneity; Codfishes; commercial fish species; Cretaceous-Paleogene (K-Pg); heterotachy; systematic error; target enrichment.]
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Affiliation(s)
- Adela Roa-Varón
- National Systematics Laboratory of the National Oceanic Atmospheric Administration Fisheries Service, 10th St. & Constitution Ave. NW, Washington, DC 20560, USA.,Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, 10th St. & Constitution Ave. NW, Washington, DC 20560, USA.,Virginia Institute of Marine Science, William & Mary, Gloucester Point, VA 23062, USA
| | - Rebecca B Dikow
- Data Science Lab, Office of the Chief Information Officer, Smithsonian Institution, 10th St. & Constitution Ave. NW, Washington, DC 20560, USA
| | - Giorgio Carnevale
- Dipartimento di Scienze della Terra, Università degli Studi di Torino, Via Valperga Caluso, 35, 10125 Torino, Italy
| | - Luke Tornabene
- School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat Street, Seattle, WA 98105, USA.,Burke Museum of Natural History and Culture, 4300 15th Ave NE, Seattle, WA 98105, USA
| | - Carole C Baldwin
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, 10th St. & Constitution Ave. NW, Washington, DC 20560, USA
| | - Chenhong Li
- Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution, 999 Hucheng Ring Rd, Pudong, Shanghai, China
| | - Eric J Hilton
- Virginia Institute of Marine Science, William & Mary, Gloucester Point, VA 23062, USA
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8
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Biswal DP, Panigrahi KCS. Light- and hormone-mediated development in non-flowering plants: An overview. PLANTA 2020; 253:1. [PMID: 33245411 DOI: 10.1007/s00425-020-03501-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 10/21/2020] [Indexed: 06/11/2023]
Abstract
Light, hormones and their interaction regulate different aspects of development in non-flowering plants. They might have played a role in the evolution of different plant groups by conferring specific adaptive evolutionary changes. Plants are sessile organisms. Unlike animals, they lack the opportunity to abandon their habitat in unfavorable conditions. They respond to different environmental cues and adapt accordingly to control their growth and developmental pattern. While phytohormones are known to be internal regulators of plant development, light is a major environmental signal that shapes plant processes. It is plausible that light-hormone crosstalk might have played an important role in plant evolution. But how the crosstalk between light and phytohormone signaling pathways might have shaped the plant evolution is unclear. One of the possible reasons is that flowering plants have been studied extensively in context of plant development, which cannot serve the purpose of evolutionary comparisons. In order to elucidate the role of light, hormone and their crosstalk in the evolutionary adaptation in plant kingdom, one needs to understand various light- and hormone-mediated processes in diverse non-flowering plants. This review is an attempt to outline major light- and phytohormone-mediated responses in non-flowering plant groups such as algae, bryophytes, pteridophytes and gymnosperms.
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Affiliation(s)
- Durga Prasad Biswal
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, Odisha, India
- Homi Bhabha National Institute (HBNI), Training School Complex, Anushakti Nagar, Mumbai, 400094, India
| | - Kishore Chandra Sekhar Panigrahi
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, Odisha, India.
- Homi Bhabha National Institute (HBNI), Training School Complex, Anushakti Nagar, Mumbai, 400094, India.
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9
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Alakärppä E, Taulavuori E, Valledor L, Marttila T, Jokipii-Lukkari S, Karppinen K, Nguyen N, Taulavuori K, Häggman H. Early growth of Scots pine seedlings is affected by seed origin and light quality. JOURNAL OF PLANT PHYSIOLOGY 2019; 237:120-128. [PMID: 31078909 DOI: 10.1016/j.jplph.2019.03.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/22/2019] [Accepted: 03/22/2019] [Indexed: 06/09/2023]
Abstract
Plants have evolved a suite of photoreceptors to perceive information from the surrounding light conditions. The aim of this study was to examine photomorphogenic effects of light quality on the growth of Scots pine (Pinus sylvestris L.) seedlings representing southern (60 °N) and northern (68 °N) origins in Finland. We measured the growth characteristics and the expression of light-responsive genes from seedlings grown under two LED light spectra: (1) Retarder (blue and red wavelengths in ratio 0.7) inducing compact growth, and (2) Booster (moderate in blue, green and far-red wavelengths, and high intensity of red light) promoting shoot elongation. The results show that root elongation, biomass, and branching were reduced under Retarder spectrum in the seedlings representing both origins, while inhibition in seed germination and shoot elongation was mainly detected in the seedlings of northern origin. The expression of ZTL and HY5 was related to Scots pine growth under both light spectra. Moreover, the expression of PHYN correlated with growth when exposed to Retarder, whereas CRY2 expression was associated with growth under Booster. Our data indicates that blue light and the deficiency of far-red light limit the growth of Scots pine seedlings and that northern populations are more sensitive to blue light than southern populations. Furthermore, the data analyses suggest that ZTL and HY5 broadly participate in the light-mediated growth regulation of Scots pine, whereas PHYN responses to direct sunlight and the role of CRY2 is in shade avoidance. Altogether, our study extends the knowledge of light quality and differential gene expression affecting the early growth of Scots pines representing different latitudinal origins.
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Affiliation(s)
- Emmi Alakärppä
- Ecology and Genetics Research Unit, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland.
| | - Erja Taulavuori
- Ecology and Genetics Research Unit, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland.
| | - Luis Valledor
- Plant Physiology, Faculty of Biology, University of Oviedo, Cat. Rodrígo Uría s/n, E-33071, Oviedo, Spain.
| | - Toni Marttila
- Ecology and Genetics Research Unit, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland.
| | - Soile Jokipii-Lukkari
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, P.O. Box 27, FI-00014, Helsinki, Finland.
| | - Katja Karppinen
- Ecology and Genetics Research Unit, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland.
| | - Nga Nguyen
- Ecology and Genetics Research Unit, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland.
| | - Kari Taulavuori
- Ecology and Genetics Research Unit, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland.
| | - Hely Häggman
- Ecology and Genetics Research Unit, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland.
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10
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Hohmann N, Wolf EM, Rigault P, Zhou W, Kiefer M, Zhao Y, Fu CX, Koch MA. Ginkgo biloba's footprint of dynamic Pleistocene history dates back only 390,000 years ago. BMC Genomics 2018; 19:299. [PMID: 29703145 PMCID: PMC5921299 DOI: 10.1186/s12864-018-4673-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 04/13/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND At the end of the Pliocene and the beginning of Pleistocene glaciation and deglaciation cycles Ginkgo biloba went extinct all over the world, and only few populations remained in China in relict areas serving as sanctuary for Tertiary relict trees. Yet the status of these regions as refuge areas with naturally existing populations has been proven not earlier than one decade ago. Herein we elaborated the hypothesis that during the Pleistocene cooling periods G. biloba expanded its distribution range in China repeatedly. Whole plastid genomes were sequenced, assembled and annotated, and sequence data was analyzed in a phylogenetic framework of the entire gymnosperms to establish a robust spatio-temporal framework for gymnosperms and in particular for G. biloba Pleistocene evolutionary history. RESULTS Using a phylogenetic approach, we identified that Ginkgoatae stem group age is about 325 million years, whereas crown group radiation of extant Ginkgo started not earlier than 390,000 years ago. During repeated warming phases, Gingko populations were separated and isolated by contraction of distribution range and retreated into mountainous regions serving as refuge for warm-temperate deciduous forests. Diversification and phylogenetic splits correlate with the onset of cooling phases when Ginkgo expanded its distribution range and gene pools merged. CONCLUSIONS Analysis of whole plastid genome sequence data representing the entire spatio-temporal genetic variation of wild extant Ginkgo populations revealed the deepest temporal footprint dating back to approximately 390,000 years ago. Present-day directional West-East admixture of genetic diversity is shown to be the result of pronounced effects of the last cooling period. Our evolutionary framework will serve as a conceptual roadmap for forthcoming genomic sequence data, which can then provide deep insights into the demographic history of Ginkgo.
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Affiliation(s)
- Nora Hohmann
- Center for Organismal Studies (COS) Heidelberg/Botanic Garden and Herbarium Heidelberg (HEID), University of Heidelberg, Im Neuenheimer Feld 345, D-69120, Heidelberg, Germany.,Present address: Department of Environmental Sciences, Botany, University of Basel, Schönbeinstrasse 6, CH-4056, Basel, Switzerland
| | - Eva M Wolf
- Center for Organismal Studies (COS) Heidelberg/Botanic Garden and Herbarium Heidelberg (HEID), University of Heidelberg, Im Neuenheimer Feld 345, D-69120, Heidelberg, Germany
| | - Philippe Rigault
- Center for Organismal Studies (COS) Heidelberg/Botanic Garden and Herbarium Heidelberg (HEID), University of Heidelberg, Im Neuenheimer Feld 345, D-69120, Heidelberg, Germany.,GYDLE Inc., 1135 Grande Allée Ouest, Suite 220, QC, Québec, G1S 1E7, Canada
| | - Wenbin Zhou
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Markus Kiefer
- Center for Organismal Studies (COS) Heidelberg/Botanic Garden and Herbarium Heidelberg (HEID), University of Heidelberg, Im Neuenheimer Feld 345, D-69120, Heidelberg, Germany
| | - Yunpeng Zhao
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Cheng-Xin Fu
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Marcus A Koch
- Center for Organismal Studies (COS) Heidelberg/Botanic Garden and Herbarium Heidelberg (HEID), University of Heidelberg, Im Neuenheimer Feld 345, D-69120, Heidelberg, Germany.
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Qu XJ, Jin JJ, Chaw SM, Li DZ, Yi TS. Multiple measures could alleviate long-branch attraction in phylogenomic reconstruction of Cupressoideae (Cupressaceae). Sci Rep 2017; 7:41005. [PMID: 28120880 PMCID: PMC5264392 DOI: 10.1038/srep41005] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 12/12/2016] [Indexed: 11/18/2022] Open
Abstract
Long-branch attraction (LBA) is a major obstacle in phylogenetic reconstruction. The phylogenetic relationships among Juniperus (J), Cupressus (C) and the Hesperocyparis-Callitropsis-Xanthocyparis (HCX) subclades of Cupressoideae are controversial. Our initial analyses of plastid protein-coding gene matrix revealed both J and C with much longer stem branches than those of HCX, so their sister relationships may be attributed to LBA. We used multiple measures including data filtering and modifying, evolutionary model selection and coalescent phylogenetic reconstruction to alleviate the LBA artifact. Data filtering by strictly removing unreliable aligned regions and removing substitution saturation genes and rapidly evolving sites could significantly reduce branch lengths of subclades J and C and recovered a relationship of J (C, HCX). In addition, using coalescent phylogenetic reconstruction could elucidate the LBA artifact and recovered J (C, HCX). However, some valid methods for other taxa were inefficient in alleviating the LBA artifact in J-C-HCX. Different strategies should be carefully considered and justified to reduce LBA in phylogenetic reconstruction of different groups. Three subclades of J-C-HCX were estimated to have experienced ancient rapid divergence within a short period, which could be another major obstacle in resolving relationships. Furthermore, our plastid phylogenomic analyses fully resolved the intergeneric relationships of Cupressoideae.
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Affiliation(s)
- Xiao-Jian Qu
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
- Kunming College of Life Sciences, University of Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Jian-Jun Jin
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
- Kunming College of Life Sciences, University of Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Shu-Miaw Chaw
- Biodiversity Research Center, Academia Sinica, Nankang District, Taipei 11529, Taiwan
| | - De-Zhu Li
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
- Kunming College of Life Sciences, University of Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Ting-Shuang Yi
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
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12
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Jud NA. Morphotype Catalog of a Zone I (Aptian—Earliest Albian) Flora from Fairlington, Virginia, USA. BULLETIN OF THE PEABODY MUSEUM OF NATURAL HISTORY 2014. [DOI: 10.3374/014.055.0204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Evolution and biogeography of gymnosperms. Mol Phylogenet Evol 2014; 75:24-40. [DOI: 10.1016/j.ympev.2014.02.005] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 02/06/2014] [Accepted: 02/10/2014] [Indexed: 11/20/2022]
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Reconstructing the age and historical biogeography of the ancient flowering-plant family Hydatellaceae (Nymphaeales). BMC Evol Biol 2014; 14:102. [PMID: 24884487 PMCID: PMC4030046 DOI: 10.1186/1471-2148-14-102] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 05/01/2014] [Indexed: 12/26/2022] Open
Abstract
Background The aquatic flowering-plant family Hydatellaceae has a classic Gondwanan distribution, as it is found in Australia, India and New Zealand. To shed light on the biogeographic history of this apparently ancient branch of angiosperm phylogeny, we dated the family in the context of other seed-plant divergences, and evaluated its biogeography using parsimony and likelihood methods. We also explicitly tested the effect of different extinction rates on biogeographic inferences. Results We infer that the stem lineage of Hydatellaceae originated in the Lower Cretaceous; in contrast, its crown originated much more recently, in the early Miocene, with the bulk of its diversification after the onset of the Pliocene. Biogeographic reconstructions predict a mix of dispersal and vicariance events, but considerations of geological history preclude most vicariance events, besides a split at the root of the family between southern and northern clades. High extinction rates are plausible in the family, and when these are taken into account there is greater uncertainty in biogeographic inferences. Conclusions A stem origin for Hydatellaceae in the Lower Cretaceous is consistent with the initial appearance of fossils attributed to its sister clade, the water lilies. In contrast, the crown clade is young, indicating that vicariant explanations for species outside Australia are improbable. Although long-distance dispersal is likely the primary driver of biogeographic distribution in Hydatellaceae, we infer that the recent drying out of central Australia divided the family into tropical vs. subtropical/temperate clades around the beginning of the Miocene.
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Li FW, Villarreal JC, Kelly S, Rothfels CJ, Melkonian M, Frangedakis E, Ruhsam M, Sigel EM, Der JP, Pittermann J, Burge DO, Pokorny L, Larsson A, Chen T, Weststrand S, Thomas P, Carpenter E, Zhang Y, Tian Z, Chen L, Yan Z, Zhu Y, Sun X, Wang J, Stevenson DW, Crandall-Stotler BJ, Shaw AJ, Deyholos MK, Soltis DE, Graham SW, Windham MD, Langdale JA, Wong GKS, Mathews S, Pryer KM. Horizontal transfer of an adaptive chimeric photoreceptor from bryophytes to ferns. Proc Natl Acad Sci U S A 2014; 111:6672-7. [PMID: 24733898 PMCID: PMC4020063 DOI: 10.1073/pnas.1319929111] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ferns are well known for their shade-dwelling habits. Their ability to thrive under low-light conditions has been linked to the evolution of a novel chimeric photoreceptor--neochrome--that fuses red-sensing phytochrome and blue-sensing phototropin modules into a single gene, thereby optimizing phototropic responses. Despite being implicated in facilitating the diversification of modern ferns, the origin of neochrome has remained a mystery. We present evidence for neochrome in hornworts (a bryophyte lineage) and demonstrate that ferns acquired neochrome from hornworts via horizontal gene transfer (HGT). Fern neochromes are nested within hornwort neochromes in our large-scale phylogenetic reconstructions of phototropin and phytochrome gene families. Divergence date estimates further support the HGT hypothesis, with fern and hornwort neochromes diverging 179 Mya, long after the split between the two plant lineages (at least 400 Mya). By analyzing the draft genome of the hornwort Anthoceros punctatus, we also discovered a previously unidentified phototropin gene that likely represents the ancestral lineage of the neochrome phototropin module. Thus, a neochrome originating in hornworts was transferred horizontally to ferns, where it may have played a significant role in the diversification of modern ferns.
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Affiliation(s)
- Fay-Wei Li
- Department of Biology, Duke University, Durham, NC 27708
| | - Juan Carlos Villarreal
- Systematic Botany and Mycology, Department of Biology, University of Munich, 80638 Munich, Germany
| | - Steven Kelly
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Carl J. Rothfels
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
| | - Michael Melkonian
- Botany Department, Cologne Biocenter, University of Cologne, 50674 Cologne, Germany
| | | | - Markus Ruhsam
- Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, Scotland
| | - Erin M. Sigel
- Department of Biology, Duke University, Durham, NC 27708
| | - Joshua P. Der
- Department of Biology and
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802
| | - Jarmila Pittermann
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95064
| | | | | | - Anders Larsson
- Systematic Biology, Evolutionary Biology Centre, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Tao Chen
- Fairy Lake Botanical Garden, Shenzhen, Guangdong 518004, China
| | - Stina Weststrand
- Systematic Biology, Evolutionary Biology Centre, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Philip Thomas
- Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, Scotland
| | - Eric Carpenter
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E9
| | | | | | - Li Chen
- BGI-Shenzhen, Shenzhen 518083, China
| | | | - Ying Zhu
- BGI-Shenzhen, Shenzhen 518083, China
| | - Xiao Sun
- BGI-Shenzhen, Shenzhen 518083, China
| | - Jun Wang
- BGI-Shenzhen, Shenzhen 518083, China
| | | | | | | | - Michael K. Deyholos
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E9
| | - Douglas E. Soltis
- Florida Museum of Natural History
- Department of Biology, and
- Genetics Institute, University of Florida, Gainesville, FL 32611
| | - Sean W. Graham
- Department of Botany, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
| | | | - Jane A. Langdale
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Gane Ka-Shu Wong
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E9
- BGI-Shenzhen, Shenzhen 518083, China
- Department of Medicine, University of Alberta, Edmonton, AB, Canada T6G 2E1; and
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Plastid phylogenomics and green plant phylogeny: almost full circle but not quite there. BMC Biol 2014; 12:11. [PMID: 24533863 PMCID: PMC3925952 DOI: 10.1186/1741-7007-12-11] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Indexed: 11/16/2022] Open
Abstract
A study in BMC Evolutionary Biology represents the most comprehensive effort to clarify the phylogeny of green plants using sequences from the plastid genome. This study highlights the strengths and limitations of plastome data for resolving the green plant phylogeny, and points toward an exciting future for plant phylogenetics, during which the vast and largely untapped territory of nuclear genomes will be explored.
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17
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Ruhfel BR, Gitzendanner MA, Soltis PS, Soltis DE, Burleigh JG. From algae to angiosperms-inferring the phylogeny of green plants (Viridiplantae) from 360 plastid genomes. BMC Evol Biol 2014; 14:23. [PMID: 24533922 PMCID: PMC3933183 DOI: 10.1186/1471-2148-14-23] [Citation(s) in RCA: 322] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 01/13/2014] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Next-generation sequencing has provided a wealth of plastid genome sequence data from an increasingly diverse set of green plants (Viridiplantae). Although these data have helped resolve the phylogeny of numerous clades (e.g., green algae, angiosperms, and gymnosperms), their utility for inferring relationships across all green plants is uncertain. Viridiplantae originated 700-1500 million years ago and may comprise as many as 500,000 species. This clade represents a major source of photosynthetic carbon and contains an immense diversity of life forms, including some of the smallest and largest eukaryotes. Here we explore the limits and challenges of inferring a comprehensive green plant phylogeny from available complete or nearly complete plastid genome sequence data. RESULTS We assembled protein-coding sequence data for 78 genes from 360 diverse green plant taxa with complete or nearly complete plastid genome sequences available from GenBank. Phylogenetic analyses of the plastid data recovered well-supported backbone relationships and strong support for relationships that were not observed in previous analyses of major subclades within Viridiplantae. However, there also is evidence of systematic error in some analyses. In several instances we obtained strongly supported but conflicting topologies from analyses of nucleotides versus amino acid characters, and the considerable variation in GC content among lineages and within single genomes affected the phylogenetic placement of several taxa. CONCLUSIONS Analyses of the plastid sequence data recovered a strongly supported framework of relationships for green plants. This framework includes: i) the placement of Zygnematophyceace as sister to land plants (Embryophyta), ii) a clade of extant gymnosperms (Acrogymnospermae) with cycads + Ginkgo sister to remaining extant gymnosperms and with gnetophytes (Gnetophyta) sister to non-Pinaceae conifers (Gnecup trees), and iii) within the monilophyte clade (Monilophyta), Equisetales + Psilotales are sister to Marattiales + leptosporangiate ferns. Our analyses also highlight the challenges of using plastid genome sequences in deep-level phylogenomic analyses, and we provide suggestions for future analyses that will likely incorporate plastid genome sequence data for thousands of species. We particularly emphasize the importance of exploring the effects of different partitioning and character coding strategies.
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Affiliation(s)
- Brad R Ruhfel
- Department of Biological Sciences, Eastern Kentucky University, Richmond, KY 40475, USA
| | - Matthew A Gitzendanner
- Department of Biology, University of Florida, Gainesville, FL 32611-8525, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611-7800, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Pamela S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611-7800, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Douglas E Soltis
- Department of Biology, University of Florida, Gainesville, FL 32611-8525, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611-7800, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - J Gordon Burleigh
- Department of Biology, University of Florida, Gainesville, FL 32611-8525, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
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Turner B, Munzinger J, Duangjai S, Temsch EM, Stockenhuber R, Barfuss MHJ, Chase MW, Samuel R. Molecular phylogenetics of New Caledonian Diospyros (Ebenaceae) using plastid and nuclear markers. Mol Phylogenet Evol 2013; 69:740-63. [PMID: 23850609 PMCID: PMC3913082 DOI: 10.1016/j.ympev.2013.07.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 07/01/2013] [Accepted: 07/03/2013] [Indexed: 01/11/2023]
Abstract
To clarify phylogenetic relationships among New Caledonian species of Diospyros, sequences of four plastid markers (atpB, rbcL, trnK-matK and trnS-trnG) and two low-copy nuclear markers (ncpGS and PHYA) were analysed. New Caledonian Diospyros species fall into three clades, two of which have only a few members (1 or 5 species); the third has 21 closely related species for which relationships among species have been mostly unresolved in a previous study. Although species of the third group (NC clade III) are morphologically distinct and largely occupy different habitats, they exhibit little molecular variability. Diospyros vieillardii is sister to the rest of the NC clade III, followed by D. umbrosa and D. flavocarpa, which are sister to the rest of this clade. Species from coastal habitats of western Grande Terre (D. cherrieri and D. veillonii) and some found on coralline substrates (D. calciphila and D. inexplorata) form two well-supported subgroups. The species of NC clade III have significantly larger genomes than found in diploid species of Diospyros from other parts of the world, but they all appear to be diploids. By applying a molecular clock, we infer that the ancestor of the NC clade III arrived in New Caledonia around 9 million years ago. The oldest species are around 7 million years old and the youngest ones probably much less than 1 million years.
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Affiliation(s)
- Barbara Turner
- Department of Systematic and Evolutionary Botany, Faculty of Life Sciences, University Vienna, Rennweg 14, 1030 Wien, Austria.
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Xi Z, Rest JS, Davis CC. Phylogenomics and coalescent analyses resolve extant seed plant relationships. PLoS One 2013; 8:e80870. [PMID: 24278335 PMCID: PMC3836751 DOI: 10.1371/journal.pone.0080870] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 10/15/2013] [Indexed: 12/29/2022] Open
Abstract
The extant seed plants include more than 260,000 species that belong to five main lineages: angiosperms, conifers, cycads, Ginkgo, and gnetophytes. Despite tremendous effort using molecular data, phylogenetic relationships among these five lineages remain uncertain. Here, we provide the first broad coalescent-based species tree estimation of seed plants using genome-scale nuclear and plastid data By incorporating 305 nuclear genes and 47 plastid genes from 14 species, we identify that i) extant gymnosperms (i.e., conifers, cycads, Ginkgo, and gnetophytes) are monophyletic, ii) gnetophytes exhibit discordant placements within conifers between their nuclear and plastid genomes, and iii) cycads plus Ginkgo form a clade that is sister to all remaining extant gymnosperms. We additionally observe that the placement of Ginkgo inferred from coalescent analyses is congruent across different nucleotide rate partitions. In contrast, the standard concatenation method produces strongly supported, but incongruent placements of Ginkgo between slow- and fast-evolving sites. Specifically, fast-evolving sites yield relationships in conflict with coalescent analyses. We hypothesize that this incongruence may be related to the way in which concatenation methods treat sites with elevated nucleotide substitution rates. More empirical and simulation investigations are needed to understand this potential weakness of concatenation methods.
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Affiliation(s)
- Zhenxiang Xi
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Joshua S. Rest
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, New York, United States of America
| | - Charles C. Davis
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States of America
- * E-mail:
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Little SA, Jacobs B, McKechnie SJ, Cooper RL, Christianson ML, Jernstedt JA. Branch architecture in Ginkgo biloba: wood anatomy and long shoot-short shoot interactions. AMERICAN JOURNAL OF BOTANY 2013; 100:1923-1935. [PMID: 24061214 DOI: 10.3732/ajb.1300123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PREMISE Ginkgo, centrally placed in seed plant phylogeny, is considered important in many phylogenetic and evolutionary studies. Shoot dimorphism of Ginkgo has been long noted, but no work has yet been done to evaluate the relationships between overall branch architecture and wood ring characters, shoot growth, and environmental conditions. • METHODS Branches, sampled from similar canopy heights, were mapped with the age of each long shoot segment determined by counting annual leaf-scar series on its short shoots. Transverse sections were made for each long shoot segment and an adjacent short shoot; wood ring thickness, number of rings, and number of tracheids/ring were determined. Using branch maps, we identified wood rings for each long shoot segment to year and developmental context of each year (distal short shoot growth only vs. at least one distal long shoot). Climate data were also analyzed in conjunction with developmental context. • KEY RESULTS Significantly thicker wood rings occur in years with distal long shoot development. The likelihood that a branch produced long shoots in a given year was lower with higher maximum annual temperature. Annual maximum temperature was negatively correlated with ring thickness in microsporangiate trees only. Annual minimum temperatures were correlated differently with ring thickness of megasporangiate and microsporangiate trees, depending on the developmental context. There were no significant effects associated with precipitation. • CONCLUSIONS Overall, developmental context alone predicts wood ring thickness about as well as models that include temperature. This suggests that although climatic factors may be strongly correlated with wood ring data among many gymnosperm taxa, at least for Ginkgo, correlations with climate data are primarily due to changes in proportions of shoot developmental types (LS vs. SS) across branches.
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Affiliation(s)
- Stefan A Little
- Department of Plant Sciences, One Shields Avenue, University of California, Davis, California 95616, USA
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21
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Primary endosymbiosis events date to the later Proterozoic with cross-calibrated phylogenetic dating of duplicated ATPase proteins. Proc Natl Acad Sci U S A 2013; 110:12355-60. [PMID: 23776247 DOI: 10.1073/pnas.1305813110] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Chloroplasts and mitochondria descended from bacterial ancestors, but the dating of these primary endosymbiosis events remains very uncertain, despite their importance for our understanding of the evolution of both bacteria and eukaryotes. All phylogenetic dating in the Proterozoic and before is difficult: Significant debates surround potential fossil calibration points based on the interpretation of the Precambrian microbial fossil record, and strict molecular clock methods cannot be expected to yield accurate dates over such vast timescales because of strong heterogeneity in rates. Even with more sophisticated relaxed-clock analyses, nodes that are distant from fossil calibrations will have a very high uncertainty in dating. However, endosymbiosis events and gene duplications provide some additional information that has never been exploited in dating; namely, that certain nodes on a gene tree must represent the same events, and thus must have the same or very similar dates, even if the exact date is uncertain. We devised techniques to exploit this information: cross-calibration, in which node date calibrations are reused across a phylogeny, and cross-bracing, in which node date calibrations are formally linked in a hierarchical Bayesian model. We apply these methods to proteins with ancient duplications that have remained associated and originated from plastid and mitochondrial endosymbionts: the α and β subunits of ATP synthase and its relatives, and the elongation factor thermo unstable. The methods yield reductions in dating uncertainty of 14-26% while only using date calibrations derived from phylogenetically unambiguous Phanerozoic fossils of multicellular plants and animals. Our results suggest that primary plastid endosymbiosis occurred ∼900 Mya and mitochondrial endosymbiosis occurred ∼1,200 Mya.
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Zimmer EA, Wen J. Reprint of: using nuclear gene data for plant phylogenetics: progress and prospects. Mol Phylogenet Evol 2013; 66:539-50. [PMID: 23375140 DOI: 10.1016/j.ympev.2013.01.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 06/14/2012] [Accepted: 07/16/2012] [Indexed: 12/25/2022]
Abstract
The paper reviews the current state of low and single copy nuclear markers that have been applied successfully in plant phylogenetics to date, and discusses case studies highlighting the potential of massively parallel high throughput or next-generation sequencing (NGS) approaches for molecular phylogenetic and evolutionary investigations. The current state, prospects and challenges of specific single- or low-copy plant nuclear markers as well as phylogenomic case studies are presented and evaluated.
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Affiliation(s)
- Elizabeth A Zimmer
- Department of Botany, National Museum of Natural History, MRC 166, Smithsonian Institution, Washington, DC 20013-7012, USA.
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23
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Zimmer EA, Wen J. Using nuclear gene data for plant phylogenetics: Progress and prospects. Mol Phylogenet Evol 2012; 65:774-85. [DOI: 10.1016/j.ympev.2012.07.015] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 06/14/2012] [Accepted: 07/16/2012] [Indexed: 10/28/2022]
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Cooke JEK, Eriksson ME, Junttila O. The dynamic nature of bud dormancy in trees: environmental control and molecular mechanisms. PLANT, CELL & ENVIRONMENT 2012; 35:1707-28. [PMID: 22670814 DOI: 10.1111/j.1365-3040.2012.02552.x] [Citation(s) in RCA: 298] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In tree species native to temperate and boreal regions, the activity-dormancy cycle is an important adaptive trait both for survival and growth. We discuss recent research on mechanisms controlling the overlapping developmental processes that define the activity-dormancy cycle, including cessation of apical growth, bud development, induction, maintenance and release of dormancy, and bud burst. The cycle involves an extensive reconfiguration of metabolism. Environmental control of the activity-dormancy cycle is based on perception of photoperiodic and temperature signals, reflecting adaptation to prevailing climatic conditions. Several molecular actors for control of growth cessation have been identified, with the CO/FT regulatory network and circadian clock having important coordinating roles in control of growth and dormancy. Other candidate regulators of bud set, dormancy and bud burst have been identified, such as dormancy-associated MADS-box factors, but their exact roles remain to be discovered. Epigenetic mechanisms also appear to factor in control of the activity-dormancy cycle. Despite evidence for gibberellins as negative regulators in growth cessation, and ABA and ethylene in bud formation, understanding of the roles that plant growth regulators play in controlling the activity-dormancy cycle is still very fragmentary. Finally, some of the challenges for further research in bud dormancy are discussed.
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Affiliation(s)
- Janice E K Cooke
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
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25
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Williams JH. Pollen Tube Growth Rates and the Diversification of Flowering Plant Reproductive Cycles. INTERNATIONAL JOURNAL OF PLANT SCIENCES 2012. [PMID: 0 DOI: 10.1086/665822] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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Mathews S, Kramer EM. The evolution of reproductive structures in seed plants: a re-examination based on insights from developmental genetics. THE NEW PHYTOLOGIST 2012; 194:910-923. [PMID: 22413867 DOI: 10.1111/j.1469-8137.2012.04091.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The study of developmental genetics is providing insights into how plant morphology can and does evolve, and into the fundamental nature of specific organs. This new understanding has the potential to revise significantly the way we think about seed plant evolution, especially with regard to reproductive structures. Here, we have sought to take a step in bridging the divide between genetic data and critical fields such as paleobotany and systematics. We discuss the evidence for several evolutionarily important interpretations, including the possibility that ovules represent meristematic axes with their own type of lateral determinate organs (integuments) and a model that considers carpels as analogs of complex leaves. In addition, we highlight the aspects of reproductive development that are likely to be highly labile and homoplastic, factors that have major implications for the understanding of seed plant relationships. Although these hypotheses may suggest that some long-standing interpretations are misleading, they also open up whole new avenues for comparative study and suggest concrete best practices for evolutionary analyses of development.
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Affiliation(s)
- Sarah Mathews
- Arnold Arboretum, Harvard University, 1300 Centre Street, Boston, MA 02131, USA
| | - Elena M Kramer
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave., Cambridge, MA, USA
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27
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Crisp MD, Cook LG. Cenozoic extinctions account for the low diversity of extant gymnosperms compared with angiosperms. THE NEW PHYTOLOGIST 2011; 192:997-1009. [PMID: 21895664 DOI: 10.1111/j.1469-8137.2011.03862.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We test the widely held notion that living gymnosperms are 'ancient' and 'living fossils' by comparing them with their sister group, the angiosperms. This perception derives partly from the lack of gross morphological differences between some Mesozoic gymnosperm fossils and their living relatives (e.g. Ginkgo, cycads and dawn redwood), suggesting that the rate of evolution of gymnosperms has been slow. We estimated the ages and diversification rates of gymnosperm lineages using Bayesian relaxed molecular clock dating calibrated with 21 fossils, based on the phylogenetic analysis of alignments of matK chloroplast DNA (cpDNA) and 26S nuclear ribosomal DNA (nrDNA) sequences, and compared these with published estimates for angiosperms. Gymnosperm crown groups of Cenozoic age are significantly younger than their angiosperm counterparts (median age: 32 Ma vs 50 Ma) and have long unbranched stems, indicating major extinctions in the Cenozoic, in contrast with angiosperms. Surviving gymnosperm genera have diversified more slowly than angiosperms during the Neogene as a result of their higher extinction rate. Compared with angiosperms, living gymnosperm groups are not ancient. The fossil record also indicates that gymnosperms suffered major extinctions when climate changed in the Oligocene and Miocene. Extant gymnosperm groups occupy diverse habitats and some probably survived after making adaptive shifts.
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Affiliation(s)
- Michael D Crisp
- Division of Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Lyn G Cook
- School of Biological Sciences, The University of Queensland, Brisbane, Qld 4072, Australia
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Wu CS, Wang YN, Hsu CY, Lin CP, Chaw SM. Loss of different inverted repeat copies from the chloroplast genomes of Pinaceae and cupressophytes and influence of heterotachy on the evaluation of gymnosperm phylogeny. Genome Biol Evol 2011; 3:1284-95. [PMID: 21933779 PMCID: PMC3219958 DOI: 10.1093/gbe/evr095] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2011] [Indexed: 12/13/2022] Open
Abstract
The relationships among the extant five gymnosperm groups--gnetophytes, Pinaceae, non-Pinaceae conifers (cupressophytes), Ginkgo, and cycads--remain equivocal. To clarify this issue, we sequenced the chloroplast genomes (cpDNAs) from two cupressophytes, Cephalotaxus wilsoniana and Taiwania cryptomerioides, and 53 common chloroplast protein-coding genes from another three cupressophytes, Agathis dammara, Nageia nagi, and Sciadopitys verticillata, and a non-Cycadaceae cycad, Bowenia serrulata. Comparative analyses of 11 conifer cpDNAs revealed that Pinaceae and cupressophytes each lost a different copy of inverted repeats (IRs), which contrasts with the view that the same IR has been lost in all conifers. Based on our structural finding, the character of an IR loss no longer conflicts with the "gnepines" hypothesis (gnetophytes sister to Pinaceae). Chloroplast phylogenomic analyses of amino acid sequences recovered incongruent topologies using different tree-building methods; however, we demonstrated that high heterotachous genes (genes that have highly different rates in different lineages) contributed to the long-branch attraction (LBA) artifact, resulting in incongruence of phylogenomic estimates. Additionally, amino acid compositions appear more heterogeneous in high than low heterotachous genes among the five gymnosperm groups. Removal of high heterotachous genes alleviated the LBA artifact and yielded congruent and robust tree topologies in which gnetophytes and Pinaceae formed a sister clade to cupressophytes (the gnepines hypothesis) and Ginkgo clustered with cycads. Adding more cupressophyte taxa could not improve the accuracy of chloroplast phylogenomics for the five gymnosperm groups. In contrast, removal of high heterotachous genes from data sets is simple and can increase confidence in evaluating the phylogeny of gymnosperms.
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Affiliation(s)
- Chung-Shien Wu
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Ya-Nan Wang
- School of Forestry and Resource Conservation, National Taiwan University, Taipei, Taiwan
| | - Chi-Yao Hsu
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Ching-Ping Lin
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Shu-Miaw Chaw
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
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Rooting phylogenies using gene duplications: An empirical example from the bees (Apoidea). Mol Phylogenet Evol 2011; 60:295-304. [DOI: 10.1016/j.ympev.2011.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 04/26/2011] [Accepted: 05/03/2011] [Indexed: 12/23/2022]
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Abercrombie JM, O'Meara BC, Moffatt AR, Williams JH. Developmental evolution of flowering plant pollen tube cell walls: callose synthase (CalS) gene expression patterns. EvoDevo 2011; 2:14. [PMID: 21722365 PMCID: PMC3146827 DOI: 10.1186/2041-9139-2-14] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 07/01/2011] [Indexed: 03/04/2023] Open
Abstract
BACKGROUND A number of innovations underlie the origin of rapid reproductive cycles in angiosperms. A critical early step involved the modification of an ancestrally short and slow-growing pollen tube for faster and longer distance transport of sperm to egg. Associated with this shift are the predominantly callose (1,3-β-glucan) walls and septae (callose plugs) of angiosperm pollen tubes. Callose synthesis is mediated by callose synthase (CalS). Of 12 CalS gene family members in Arabidopsis, only one (CalS5) has been directly linked to pollen tube callose. CalS5 orthologues are present in several monocot and eudicot genomes, but little is known about the evolutionary origin of CalS5 or what its ancestral function may have been. RESULTS We investigated expression of CalS in pollen and pollen tubes of selected non-flowering seed plants (gymnosperms) and angiosperms within lineages that diverged below the monocot/eudicot node. First, we determined the nearly full length coding sequence of a CalS5 orthologue from Cabomba caroliniana (CcCalS5) (Nymphaeales). Semi-quantitative RT-PCR demonstrated low CcCalS5 expression within several vegetative tissues, but strong expression in mature pollen. CalS transcripts were detected in pollen tubes of several species within Nymphaeales and Austrobaileyales, and comparative analyses with a phylogenetically diverse group of sequenced genomes indicated homology to CalS5. We also report in silico evidence of a putative CalS5 orthologue from Amborella. Among gymnosperms, CalS5 transcripts were recovered from germinating pollen of Gnetum and Ginkgo, but a novel CalS paralog was instead amplified from germinating pollen of Pinus taeda. CONCLUSION The finding that CalS5 is the predominant callose synthase in pollen tubes of both early-diverging and model system angiosperms is an indicator of the homology of their novel callosic pollen tube walls and callose plugs. The data suggest that CalS5 had transient expression and pollen-specific functions in early seed plants and was then recruited to novel expression patterns and functions within pollen tube walls in an ancestor of extant angiosperms.
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Affiliation(s)
- Jason M Abercrombie
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, USA.
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Schliep KP. phangorn: phylogenetic analysis in R. Bioinformatics 2011; 27:592-3. [PMID: 21169378 PMCID: PMC3035803 DOI: 10.1093/bioinformatics/btq706] [Citation(s) in RCA: 1976] [Impact Index Per Article: 152.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 11/26/2010] [Accepted: 12/14/2010] [Indexed: 12/25/2022] Open
Abstract
SUMMARY phangorn is a package for phylogenetic reconstruction and analysis in the R language. Previously it was only possible to estimate phylogenetic trees with distance methods in R. phangorn, now offers the possibility of reconstructing phylogenies with distance based methods, maximum parsimony or maximum likelihood (ML) and performing Hadamard conjugation. Extending the general ML framework, this package provides the possibility of estimating mixture and partition models. Furthermore, phangorn offers several functions for comparing trees, phylogenetic models or splits, simulating character data and performing congruence analyses. AVAILABILITY phangorn can be obtained through the CRAN homepage http://cran.r-project.org/web/packages/phangorn/index.html. phangorn is licensed under GPL 2.
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Affiliation(s)
- Klaus Peter Schliep
- UMR CNRS 7138 Systématique, Adaptation, Evolution, Université Pierre et Marie Curie, Muséum National d'Histoire Naturelle, Paris, France.
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Magallón S. Using Fossils to Break Long Branches in Molecular Dating: A Comparison of Relaxed Clocks Applied to the Origin of Angiosperms. Syst Biol 2010; 59:384-99. [DOI: 10.1093/sysbio/syq027] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Susana Magallón
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, 3er Circuito de Ciudad Universitaria, Del. Coyoacán, México D.F. 04510, México
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Crane PR, Friis EM, Chaloner WG. Darwin and the evolution of flowers. Philos Trans R Soc Lond B Biol Sci 2010; 365:347-50. [DOI: 10.1098/rstb.2009.0277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Peter R. Crane
- School of Forestry and Environmental Studies, Yale University, 195 Prospect Street, New Haven, CT 06511, USA
| | - Else Marie Friis
- Department of Palaeobotany, Swedish Museum of Natural History, Box 50007, SE-10405 Stockholm, Sweden
| | - William G. Chaloner
- Department of Earth Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK
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Mathews S. Evolutionary studies illuminate the structural-functional model of plant phytochromes. THE PLANT CELL 2010; 22:4-16. [PMID: 20118225 PMCID: PMC2828699 DOI: 10.1105/tpc.109.072280] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 01/12/2010] [Accepted: 01/13/2010] [Indexed: 05/18/2023]
Abstract
A synthesis of insights from functional and evolutionary studies reveals how the phytochrome photoreceptor system has evolved to impart both stability and flexibility. Phytochromes in seed plants diverged into three major forms, phyA, phyB, and phyC, very early in the history of seed plants. Two additional forms, phyE and phyD, are restricted to flowering plants and Brassicaceae, respectively. While phyC, D, and E are absent from at least some taxa, phyA and phyB are present in all sampled seed plants and are the principal mediators of red/far-red-induced responses. Conversely, phyC-E apparently function in concert with phyB and, where present, expand the repertoire of phyB activities. Despite major advances, aspects of the structural-functional models for these photoreceptors remain elusive. Comparative sequence analyses expand the array of locus-specific mutant alleles for analysis by revealing historic mutations that occurred during gene lineage splitting and divergence. With insights from crystallographic data, a subset of these mutants can be chosen for functional studies to test their importance and determine the molecular mechanism by which they might impact light perception and signaling. In the case of gene families, where redundancy hinders isolation of some proportion of the relevant mutants, the approach may be particularly useful.
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Affiliation(s)
- Sarah Mathews
- Arnold Arboretum of Harvard University, Cambridge, Massachusetts 02138, USA.
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