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Freire-Rallo S, Wedin M, Diederich P, Millanes AM. To explore strange new worlds - The diversification in Tremella caloplacae was linked to the adaptive radiation of the Teloschistaceae. Mol Phylogenet Evol 2023; 180:107680. [PMID: 36572164 DOI: 10.1016/j.ympev.2022.107680] [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: 12/13/2021] [Revised: 09/12/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022]
Abstract
Lichenicolous fungi are a heterogeneous group of organisms that grow exclusively on lichens, forming obligate associations with them. It has often been assumed that cospeciation has occurred between lichens and lichenicolous fungi, but this has been seldom analysed from a macroevolutionary perspective. Many lichenicolous species are rare or are rarely observed, which results in frequent and large gaps in the knowledge of the diversity of many groups. This, in turn, hampers evolutionary studies that necessarily are based on a reasonable knowledge of this diversity. Tremella caloplacae is a heterobasidiomycete growing on various hosts from the lichen-forming family Teloschistaceae, and evidence suggests that it may represent a species complex. We combine an exhaustive sampling with molecular and ecological data to study species delimitation, cophylogenetic events and temporal concordance of this association. Tremella caloplacae is here shown to include at least six distinct host-specific lineages (=putative species). Host switch is the dominant and most plausible event influencing diversification and explaining the coupled evolutionary history in this system, although cospeciation cannot be discarded. Speciation in T. caloplacae would therefore have occurred coinciding with the rapid diversification - by an adaptive radiation starting in the late Cretaceous - of their hosts. New species in T. caloplacae would have developed as a result of specialization on diversifying lichen hosts that suddenly offered abundant new ecological niches to explore or adapt to.
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Affiliation(s)
- Sandra Freire-Rallo
- Rey Juan Carlos University/Departamento de Biología y Geología, Física y Química Inorgánica, E-28933 Móstoles, Spain
| | - Mats Wedin
- Swedish Museum of Natural History/Botany Dept., PO Box 50007, SE-10405 Stockholm, Sweden.
| | - Paul Diederich
- Musée national d'histoire naturelle, 25 rue Munster, L-2160 Luxembourg, Luxembourg
| | - Ana M Millanes
- Rey Juan Carlos University/Departamento de Biología y Geología, Física y Química Inorgánica, E-28933 Móstoles, Spain
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The yeast lichenosphere: High diversity of basidiomycetes from the lichens Tephromela atra and Rhizoplaca melanophthalma. Fungal Biol 2022; 126:587-608. [DOI: 10.1016/j.funbio.2022.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/26/2022] [Accepted: 07/13/2022] [Indexed: 01/03/2023]
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Transcriptomics Reveals the Putative Mycoparasitic Strategy of the Mushroom Entoloma abortivum on Species of the Mushroom Genus Armillaria. mSystems 2021; 6:e0054421. [PMID: 34636668 PMCID: PMC8510539 DOI: 10.1128/msystems.00544-21] [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] [Indexed: 12/13/2022] Open
Abstract
During mycoparasitism, a fungus—the host—is parasitized by another fungus—the mycoparasite. The genetic underpinnings of these relationships have been best characterized in ascomycete fungi. However, within basidiomycete fungi, there are rare instances of mushroom-forming species parasitizing the reproductive structures, or sporocarps, of other mushroom-forming species, which have been rarely investigated on a genetic level. One of the most enigmatic of these occurs between Entoloma abortivum and species of Armillaria, where hyphae of E. abortivum are hypothesized to disrupt the development of Armillaria sporocarps, resulting in the formation of carpophoroids. However, it remains unknown whether carpophoroids are the direct result of a mycoparasitic relationship. To address the nature of this unique interaction, we analyzed gene expression of field-collected Armillaria and E. abortivum sporocarps and carpophoroids. Transcripts in the carpophoroids are primarily from E. abortivum, supporting the hypothesis that this species is parasitizing Armillaria. Most notably, we identified differentially upregulated E. abortivum β-trefoil-type lectins in the carpophoroid, which we hypothesize bind to Armillaria cell wall galactomannoproteins, thereby mediating recognition between the mycoparasite and the host. The most differentially upregulated E. abortivum transcripts in the carpophoroid code for oxalate decarboxylases—enzymes that degrade oxalic acid. Oxalic acid is a virulence factor in many plant pathogens, including Armillaria species; however, E. abortivum has evolved a sophisticated strategy to overcome this defense mechanism. The number of gene models and genes that code for carbohydrate-active enzymes in the E. abortivum transcriptome was reduced compared to other closely related species, perhaps as a result of the specialized nature of this interaction. IMPORTANCE By studying fungi that parasitize other fungi, we can understand the basic biology of these unique interactions. Studies focused on the genetic mechanisms regulating mycoparasitism between host and parasite have thus far concentrated on a single fungal lineage within the Ascomycota. The work presented here expands our understanding of mycoparasitic relationships to the Basidiomycota and represents the first transcriptomic study to our knowledge that examines fungal-fungal relationships in their natural setting. The results presented here suggest that even distantly related mycoparasites utilize similar mechanisms to parasitize their host. Given that species of the mushroom-forming pathogen Armillaria cause plant root-rot diseases in many agroecosystems, an enhanced understanding of this interaction may contribute to better control of these diseases through biocontrol applications.
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Fan LF, Alvarenga RLM, Gibertoni TB, Wu F, Dai YC. Four new species in the Tremellafibulifera complex (Tremellales, Basidiomycota). MycoKeys 2021; 82:33-56. [PMID: 34393591 PMCID: PMC8357700 DOI: 10.3897/mycokeys.82.63241] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 07/12/2021] [Indexed: 11/13/2022] Open
Abstract
Samples of species close to Tremellafibulifera from China and Brazil are studied, and T.fibulifera is confirmed as a species complex including nine species. Five known species (T.cheejenii, T.fibulifera s.s., T. “neofibulifera”, T.lloydiae-candidae and T.olens) and four new species (T.australe, T.guangxiensis, T.latispora and T.subfibulifera) in the complex are recognized based on morphological characteristics, molecular evidence, and geographic distribution. Sequences of eight species of the complex were included in the phylogenetic analyses because T.olens lacks molecular data. The phylogenetic analyses were performed by a combined sequence dataset of the internal transcribed spacer (ITS) and the partial nuclear large subunit rDNA (nLSU), and a combined sequence dataset of the ITS, partial nLSU, the small subunit mitochondrial rRNA gene (mtSSU), the translation elongation factor 1-α (TEF1), the largest and second largest subunits of RNA polymerase II (RPB1 and RPB2). The eight species formed eight independent lineages with robust support in phylogenies based on both datasets. Illustrated description of the six species including Tremellafibulifera s.s., T. “neofibulifera” and four new species, and discussions with their related species, are provided. A table of the comparison of the important characteristics of nine species in the T.fibulifera complex and a key to the whitish species in Tremella s.s. are provided.
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Affiliation(s)
- Long-Fei Fan
- Institute of Microbiology, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China.,College of Forestry, Beijing Forestry University, Beijing 100083, China
| | - Renato Lúcio Mendes Alvarenga
- Departamento de Micologia, Centro de Biociências, Universidade Federal de Pernambuco, Av. da Engenharia s/n, Recife, Pernambuco 50740-570, Brazil
| | - Tatiana Baptista Gibertoni
- Departamento de Micologia, Centro de Biociências, Universidade Federal de Pernambuco, Av. da Engenharia s/n, Recife, Pernambuco 50740-570, Brazil
| | - Fang Wu
- Institute of Microbiology, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
| | - Yu-Cheng Dai
- Institute of Microbiology, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
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Mack J, Assabgui R, Seifert K. Taxonomy and phylogeny of the basidiomycetous hyphomycete genus Hormomyces. Fungal Syst Evol 2021; 7:177-196. [PMID: 34124623 PMCID: PMC8166209 DOI: 10.3114/fuse.2021.07.09] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/21/2021] [Indexed: 01/08/2023] Open
Abstract
The taxonomy of the genus Hormomyces, typified by Hormomyces aurantiacus, which based on circumstantial evidence was long assumed to be the hyphomycetous asexual morph of Tremella mesenterica (Tremellales, Tremellomycetes) or occasionally Dacrymyces (Dacrymycetales, Dacrymycetes), is revised. Phylogenies based on the three nuc rDNA markers [internal transcribed spacers (ITS), 28S large ribosomal subunit nrDNA (28S) and 18S small ribosomal subunit nrDNA (18S)], based on cultures from Canada and the United States, suggest that the genus is synonymous with Tulasnella (Cantharellales, Agaricomycetes) rather than Tremella or Dacrymyces. Morphological studies of 38 fungarium specimens of Hormomyces, including the type specimens of H. callorioides, H. fragiformis, H. paridiphilus and H. peniophorae and examination of the protologues of H. abieticola, H. aurantiacus and H. pezizoideus suggest that H. callorioides and H. fragiformis are conspecific with H. aurantiacus while the remaining species are unlikely to be related to Tulasnella. The conidial chains produced by H. aurantiacus are similar to monilioid cells of asexual morphs of Tulasnella species formerly referred to the genus Epulorhiza. The new combination Tulasnella aurantiaca is proposed and the species is redescribed, illustrated and compared with similar fungi. The ecological niche of T. aurantiaca and its possible relationship to orchid root endophytes is discussed. A key to asexual genera with similar conidium ontogeny to T. aurantiaca is provided. Citation: Mack J, Assabgui RA, Seifert KA (2021). Taxonomy and phylogeny of the basidiomycetous hyphomycete genus Hormomyces. Fungal Systematics and Evolution 7: 177-196. doi: 10.3114/fuse.2021.07.09.
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Affiliation(s)
- J. Mack
- Biodiversity (Mycology and Microbiology), Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - R.A. Assabgui
- Biodiversity (Mycology and Microbiology), Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
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Tuovinen V, Millanes AM, Freire-Rallo S, Rosling A, Wedin M. Tremella macrobasidiata and Tremella variae have abundant and widespread yeast stages in Lecanora lichens. Environ Microbiol 2021; 23:2484-2498. [PMID: 33684261 DOI: 10.1111/1462-2920.15455] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/03/2021] [Accepted: 03/03/2021] [Indexed: 01/22/2023]
Abstract
Dimorphism is a widespread feature of tremellalean fungi in general, but a little-studied aspect of the biology of lichen-associated Tremella. We show that Tremella macrobasidiata and Tremella variae have an abundant and widespread yeast stage in their life cycles that occurs in Lecanora lichens. Their sexual filamentous stage is restricted to a specific lichen: T. macrobasidiata only forms basidiomata on Lecanora chlarotera hymenia and T. variae only on Lecanora varia thalli. However, the yeast stage of T. macrobasidiata is less specific and can occur in L. varia lichens, whilst all life stages of T. variae may be specific to L. varia. Contrary to the hyphal stages, the yeasts are distributed across the thalli and hymenia of Lecanora lichens, and not limited to specimens with basidiomata. Tremella macrobasidiata was present in all studied L. chlarotera, and in 59% of L. varia specimens. Only in 8% of the L. varia thalli could none of the two Tremella species be detected. Our results indicate that lichen-associated Tremella may be much more abundant and widespread than previously assumed leading to skewed estimations about their distribution ranges and lichen specificity, and raise new questions about their biology, ecology and function in the symbiosis.
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Affiliation(s)
- Veera Tuovinen
- Department of Ecology and Genetics, Uppsala University, Uppsala, Norbyvägen 18D, 752 36, Sweden.,Department of Botany, Swedish Museum of Natural History, Stockholm, P.O. Box 50007, SE-104 05, Sweden
| | - Ana Maria Millanes
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, Móstoles, E-28933, Spain
| | - Sandra Freire-Rallo
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, Móstoles, E-28933, Spain
| | - Anna Rosling
- Department of Ecology and Genetics, Uppsala University, Uppsala, Norbyvägen 18D, 752 36, Sweden
| | - Mats Wedin
- Department of Botany, Swedish Museum of Natural History, Stockholm, P.O. Box 50007, SE-104 05, Sweden
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Zamora J, Ekman S. Phylogeny and character evolution in the Dacrymycetes, and systematics of Unilacrymaceae and Dacryonaemataceae fam. nov. PERSOONIA 2020; 44:161-205. [PMID: 33116340 PMCID: PMC7567964 DOI: 10.3767/persoonia.2020.44.07] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 10/24/2019] [Indexed: 02/07/2023]
Abstract
We present a multilocus phylogeny of the class Dacrymycetes, based on data from the 18S, ITS, 28S, RPB1, RPB2, TEF-1α, 12S, and ATP6 DNA regions, with c. 90 species including the types of most currently accepted genera. A variety of methodological approaches was used to infer phylogenetic relationships among the Dacrymycetes, from a supermatrix strategy using maximum likelihood and Bayesian inference on a concatenated dataset, to coalescence-based calculations, such as quartet-based summary methods of independent single-locus trees, and Bayesian integration of single-locus trees into a species tree under the multispecies coalescent. We evaluate for the first time the taxonomic usefulness of some cytological phenotypic characters, i.e., vacuolar contents (vacuolar bodies and lipid bodies), number of nuclei of recently discharged basidiospores, and pigments, with especial emphasis on carotenoids. These characters, along with several others traditionally used for the taxonomy of this group (basidium shape, presence and morphology of clamp connections, morphology of the terminal cells of cortical/marginal hyphae, presence and degree of ramification of the hyphidia), are mapped on the resulting phylogenies and their evolution through the class Dacrymycetes discussed. Our analyses reveal five lineages that putatively represent five different families, four of which are accepted and named. Three out of these four lineages correspond to previously circumscribed and published families (Cerinomycetaceae, Dacrymycetaceae, and Unilacrymaceae), and one is proposed as the new family Dacryonaemataceae. Provisionally, only a single order, Dacrymycetales, is accepted within the class. Furthermore, the systematics of the two smallest families, Dacryonaemataceae and Unilacrymaceae, are investigated to the species level, using coalescence-based species delimitation on multilocus DNA data, and a detailed morphological study including morphometric analyses of the basidiospores. Three species are accepted in Dacryonaema, the type, Da. rufum, the newly combined Da. macnabbii (basionym Dacrymyces macnabbii), and a new species named Da. macrosporum. Two species are accepted in Unilacryma, the new U. bispora, and the type, U. unispora, the latter treated in a broad sense pending improved sampling across the Holarctic.
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Affiliation(s)
- J.C. Zamora
- Museum of Evolution, Uppsala University, Norbyvägen 16, SE-75236 Uppsala, Sweden
- Departamento de Biología Vegetal II, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, plaza de Ramón y Cajal s/n, E-28040, Madrid, Spain
| | - S. Ekman
- Museum of Evolution, Uppsala University, Norbyvägen 16, SE-75236 Uppsala, Sweden
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He MQ, Zhao RL, Hyde KD, Begerow D, Kemler M, Yurkov A, McKenzie EHC, Raspé O, Kakishima M, Sánchez-Ramírez S, Vellinga EC, Halling R, Papp V, Zmitrovich IV, Buyck B, Ertz D, Wijayawardene NN, Cui BK, Schoutteten N, Liu XZ, Li TH, Yao YJ, Zhu XY, Liu AQ, Li GJ, Zhang MZ, Ling ZL, Cao B, Antonín V, Boekhout T, da Silva BDB, De Crop E, Decock C, Dima B, Dutta AK, Fell JW, Geml J, Ghobad-Nejhad M, Giachini AJ, Gibertoni TB, Gorjón SP, Haelewaters D, He SH, Hodkinson BP, Horak E, Hoshino T, Justo A, Lim YW, Menolli N, Mešić A, Moncalvo JM, Mueller GM, Nagy LG, Nilsson RH, Noordeloos M, Nuytinck J, Orihara T, Ratchadawan C, Rajchenberg M, Silva-Filho AGS, Sulzbacher MA, Tkalčec Z, Valenzuela R, Verbeken A, Vizzini A, Wartchow F, Wei TZ, Weiß M, Zhao CL, Kirk PM. Notes, outline and divergence times of Basidiomycota. FUNGAL DIVERS 2019. [DOI: 10.1007/s13225-019-00435-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
AbstractThe Basidiomycota constitutes a major phylum of the kingdom Fungi and is second in species numbers to the Ascomycota. The present work provides an overview of all validly published, currently used basidiomycete genera to date in a single document. An outline of all genera of Basidiomycota is provided, which includes 1928 currently used genera names, with 1263 synonyms, which are distributed in 241 families, 68 orders, 18 classes and four subphyla. We provide brief notes for each accepted genus including information on classification, number of accepted species, type species, life mode, habitat, distribution, and sequence information. Furthermore, three phylogenetic analyses with combined LSU, SSU, 5.8s, rpb1, rpb2, and ef1 datasets for the subphyla Agaricomycotina, Pucciniomycotina and Ustilaginomycotina are conducted, respectively. Divergence time estimates are provided to the family level with 632 species from 62 orders, 168 families and 605 genera. Our study indicates that the divergence times of the subphyla in Basidiomycota are 406–430 Mya, classes are 211–383 Mya, and orders are 99–323 Mya, which are largely consistent with previous studies. In this study, all phylogenetically supported families were dated, with the families of Agaricomycotina diverging from 27–178 Mya, Pucciniomycotina from 85–222 Mya, and Ustilaginomycotina from 79–177 Mya. Divergence times as additional criterion in ranking provide additional evidence to resolve taxonomic problems in the Basidiomycota taxonomic system, and also provide a better understanding of their phylogeny and evolution.
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Zhao Y, Liu XZ, Bai FY. Four new species of Tremella (Tremellales, Basidiomycota) based on morphology and DNA sequence data. MycoKeys 2019:75-95. [PMID: 30853836 PMCID: PMC6403202 DOI: 10.3897/mycokeys.47.29180] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Accepted: 01/16/2019] [Indexed: 12/31/2022] Open
Abstract
In the present study, a total of 33 Tremella specimens in China were collected and examined using molecular phylogenetic analysis based on a combined sequence dataset of the nuc rDNA internal transcribed spacer (ITS) region and nuc 28S rDNA D1/D2 domain in conjunction with the morphological characters. Four new species, namely Tremellabasidiomaticola, T.cheejenii, T.erythrina, and T.salmonea, are newly described based on their distinct phylogenetic relationships and the comparison of morphological characters with known Tremella species. Our results indicate a high species diversity of Tremella waiting to be discovered.
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Affiliation(s)
- Ying Zhao
- State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China 1 State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China 2 Key Laboratory of Microbiology Diversity Research and Application of Hebei Province, College of Life Sciences, Hebei University, Baoding 071002, PR China Beijing China.,Key Laboratory of Microbiology Diversity Research and Application of Hebei Province, College of Life Sciences, Hebei University, Baoding 071002, China 1 State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China Beijing China
| | - Xin-Zhan Liu
- State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China 1 State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China 2 Key Laboratory of Microbiology Diversity Research and Application of Hebei Province, College of Life Sciences, Hebei University, Baoding 071002, PR China Beijing China
| | - Feng-Yan Bai
- State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China 1 State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China 2 Key Laboratory of Microbiology Diversity Research and Application of Hebei Province, College of Life Sciences, Hebei University, Baoding 071002, PR China Beijing China
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Abstract
Identification of the fungus Tremella as a consistent fourth component of wolf lichens further challenges the conventional view of lichen symbiosis as a mutualistic interaction between two players.
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Affiliation(s)
- Benjamin Jenkins
- Living Systems Institute, Biosciences, University of Exeter, Geoffrey Pope Building, Exeter EX4 4QD, UK
| | - Thomas A Richards
- Living Systems Institute, Biosciences, University of Exeter, Geoffrey Pope Building, Exeter EX4 4QD, UK.
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Tuovinen V, Ekman S, Thor G, Vanderpool D, Spribille T, Johannesson H. Two Basidiomycete Fungi in the Cortex of Wolf Lichens. Curr Biol 2019; 29:476-483.e5. [PMID: 30661799 DOI: 10.1016/j.cub.2018.12.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 10/04/2018] [Accepted: 12/13/2018] [Indexed: 01/26/2023]
Abstract
Since the late 1800s, mycologists have been detecting fungi above and beyond the assumed single fungus in lichen thalli [1-6]. Over the last century, these fungi have been accorded roles ranging from commensalists to pathogens. Recently, Cyphobasidiales yeasts were shown to be ubiquitous in the cortex layer of many macrolichens [7], but for most species, little is known of their cellular distribution and constancy beyond visible fruiting structures. Here, we demonstrate the occurrence of an additional and distantly related basidiomycete, Tremella, in 95% of studied thalli in a global sample of one of the most intensively studied groups of lichens, the wolf lichens (genus Letharia). Tremella species are reported from a wide range of lichen genera [8], but until now, their biology was deduced from fruiting bodies (basidiomata) formed on lichen thalli. Based on this, they have been thought to be uncommon to rare, to occur exclusively in a hyphal form, and to be parasitic on the dominant fungal partner [9, 10]. We show that, in wolf lichens, Tremella occurs as yeast cells also in thalli that lack basidiomata and infer that this is its dominant stage in nature. We further show that the hyphal stage, when present in Letharia, is in close contact with algal cells, challenging the assumption that lichen-associated Tremella species are uniformly mycoparasites. Our results suggest that extent of occurrence and cellular interactions of known fungi within lichens have historically been underestimated and raise new questions about their function in specific lichen symbioses.
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Affiliation(s)
- Veera Tuovinen
- Department of Biological Sciences CW 405, University of Alberta, Edmonton, AB T6G 2R3, Canada; Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden; Department of Ecology, Swedish University of Agricultural Sciences, PO Box 7044, 750 07 Uppsala, Sweden.
| | - Stefan Ekman
- Museum of Evolution, Uppsala University, Norbyvägen 16, 752 36 Uppsala, Sweden
| | - Göran Thor
- Department of Ecology, Swedish University of Agricultural Sciences, PO Box 7044, 750 07 Uppsala, Sweden
| | - Dan Vanderpool
- Department of Biological Sciences, University of Montana, 32 Campus Drive, Missoula, MT 59812, USA; Department of Biology, Indiana University, 1001 East Third Street, Bloomington, IN 47405, USA
| | - Toby Spribille
- Department of Biological Sciences CW 405, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Hanna Johannesson
- Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden
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