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2.
J Fungi (Basel) ; 9(10)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37888262

RESUMO

During nocturnal field expeditions in the Brazilian Atlantic Rainforest, an unexpected bioluminescent fungus with reduced form was found. Based on morphological data, the taxon was first identified as belonging to the cyphelloid genus Maireina, but in our phylogenetic analyses, Maireina was recovered and confirmed as a paraphyletic group related to genera Merismodes and Cyphellopsis. Maireina filipendula, Ma. monacha, and Ma. subsphaerospora are herein transferred to Merismodes. Based upon morphological and molecular characters, the bioluminescent cyphelloid taxon is described as the new genus Eoscyphella, characterized by a vasiform to urceolate basidiomata, subglobose to broadly ellipsoid basidiospores, being pigmented, weakly to densely encrusted external hyphae, regularly bi-spored basidia, unclamped hyphae, and an absence of both conspicuous long external hairs and hymenial cystidia. Phylogenetic analyses based on ITS rDNA and LSU rDNA support the proposal of the new genus and confirm its position in Cyphellopsidaceae. Eoscyphella luciurceolata represents a new lineage of bioluminescent basidiomycetes with reduced forms.

3.
J Fungi (Basel) ; 9(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37623559

RESUMO

The nuclear ribosomal internal transcribed spacer (nrITS) region has been widely used in fungal diversity studies. Environmental metabarcoding has increased the importance of the fungal DNA barcode in documenting fungal diversity and distribution. The DNA barcode gap is seen as the difference between intra- and inter-specific pairwise distances in a DNA barcode. The current understanding of the barcode gap in macrofungi is limited, inhibiting the development of best practices in applying the nrITS region toward research on fungal diversity. This study examined the barcode gap using 5146 sequences representing 717 species of macrofungi from eleven genera, eight orders and two phyla in datasets assembled by taxonomic experts. Intra- and inter-specific pairwise distances were measured from sequence and phylogenetic data. The results demonstrate that barcode gaps are influenced by differences in intra- and inter-specific variance in pairwise distances. In terms of DNA barcode behavior, variance is greater in the ITS1 than ITS2, and variance is greater in both relative to the combined nrITS region. Due to the difference in variance, the barcode gaps in the ITS2 region are greater than in the ITS1. Additionally, the taxonomic approach of "splitting" taxa into numerous taxonomic units produces greater barcode gaps when compared to "lumping". The results show variability in the barcode gaps between fungal taxa, demonstrating a need to understand the accuracy of DNA barcoding in quantifying species richness. For taxonomic studies, variability in nrITS sequence data supports the application of multiple molecular markers to corroborate the taxonomic and systematic delineation of species.

4.
Mol Ecol ; 29(16): 3103-3116, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32640084

RESUMO

A phylogenetically diverse array of fungi live within healthy leaf tissue of dicotyledonous plants. Many studies have examined these endophytes within a single plant species and/or at small spatial scales, but landscape-scale variables that determine their community composition are not well understood, either across geographic space, across climatic conditions, or in the context of host plant phylogeny. Here, we evaluate the contributions of these variables to endophyte beta diversity using a survey of foliar endophytic fungi in native Hawaiian dicots sampled across the Hawaiian archipelago. We used Illumina technology to sequence fungal ITS1 amplicons to characterize foliar endophyte communities across five islands and 80 host plant genera. We found that communities of foliar endophytic fungi showed strong geographic structuring between distances of 7 and 36 km. Endophyte community structure was most strongly associated with host plant phylogeny and evapotranspiration, and was also significantly associated with NDVI, elevation and solar radiation. Additionally, our bipartite network analysis revealed that the five islands we sampled each harboured significantly specialized endophyte communities. These results demonstrate how the interaction of factors at large and small spatial and phylogenetic scales shapes fungal symbiont communities.


Assuntos
Micobioma , Biodiversidade , DNA Fúngico/genética , Endófitos/genética , Fungos/genética , Havaí , Humanos , Micobioma/genética , Havaiano Nativo ou Outro Ilhéu do Pacífico , Filogenia , Folhas de Planta
5.
Mycologia ; 111(2): 319-338, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30908110

RESUMO

Seven species of bioluminescent fungi are recorded from the cloud forests in Mexico. Six represent new species belonging to the genus Mycena, whereas Mycena globulispora is a new distribution record for the country. Descriptions, illustrations, photographs, and an identification key to bioluminescent fungi species from Mexico are provided. Sequences of nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) region were generated for barcoding purposes and comparisons with similar species.


Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Luminescência , Filogenia , Agaricales/genética , Agaricales/fisiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , México , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA
6.
Mycologia ; 108(6): 1165-1174, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27621286

RESUMO

Four species of mycenoid fungi are reported as luminescent (or putatively luminescent) on the basis of specimens collected from São Paulo State, Brazil. Two of them represent new species (Mycena oculisnymphae, Resinomycena petarensis), and two represent new reports of luminescence in previously described species (M. deformis, M. globulispora). Comprehensive descriptions, illustrations, photographs, and comparisons with phenetically similar species are provided. Sequences of nuc rDNA internal transcribed spacer regions were generated for barcoding purposes and for comparisons with similar species.


Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Agaricales/química , Agaricales/crescimento & desenvolvimento , Brasil , Análise por Conglomerados , Código de Barras de DNA Taxonômico , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Luminescência , Microscopia , Filogenia
7.
Mycologia ; 106(3): 456-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24871608

RESUMO

Pseudobaeospora wipapatiae is described as new based on material collected in alien wet habitats on the island of Hawaii. Unique features of this beautiful species include deep ruby-colored basidiomes with two-spored basidia, amyloid cheilocystidia and a hymeniderm pileipellis with abundant pileocystidia that is initially deep ruby in KOH then changes to lilac gray. Phylogenetic analysis of nuclear large ribosomal subunit sequence data suggest a close relationship between Pseudobaeospora and Tricholoma. BLAST comparisons of internal transcribed spacer and 5.8S nuclear ribosomal subunit regions sequence data reveal greatest similarity with existing sequences of Pseudobaeospora species. A comprehensive description, color photograph, illustrations of salient micromorphological features and comparisons with phenetically similar taxa are provided.


Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Agaricales/química , Agaricales/genética , Cor , Ecossistema , Havaí , Ilhas , Dados de Sequência Molecular , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação
8.
Mycologia ; 106(1): 86-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23945541

RESUMO

Phylogenetic placement of the infrageneric section Hygrometrici (genus Marasmius sensu stricto) in prior molecular phylogenetic studies have been unresolved and problematical. Molecular analyses based on newly generated ribosomal nuc-LSU and 5.8S sequences resolve members of section Hygrometrici to the family Physalacriaceae. The new genus Cryptomarasmius is proposed to accommodate members of Marasmius section Hygrometrici. Fourteen species belonging to section Hygrometrici whose available type specimens bear morphological features corresponding to the new genus are formally combined in Cryptomarasmius. Taxonomic transfers are made only for taxa in which type specimens have been studied and/or representative material sequenced. Although other species placed in section Hygrometrici may belong in Cryptomarasmius, further transfers are not proposed until additional studies on type material are conducted.


Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Agaricales/genética , DNA Fúngico/genética , DNA Ribossômico/genética , Marasmius/classificação , Marasmius/genética , Marasmius/isolamento & purificação , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
9.
Pain Med ; 15(3): 418-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24033875

RESUMO

BACKGROUND: Low back pain is a common cause of chronic pain in human immunodeficiency virus (HIV)-infected patients. The American College of Physicians and American Pain Society guidelines for diagnostic imaging in low back pain are difficult to apply to patients with chronic illnesses like HIV who may have risk factors for cancer or compression fractures, but whether imaging all such patients for low back pain improves outcomes is unknown. OBJECTIVE: Our objective was to describe patients referred to a chronic pain-focused HIV/palliative care clinic (HPCC) with back pain and their associated lumbar spine imaging findings. METHODS: We conducted a retrospective chart review of patients at a palliative care clinic that sees patients with HIV, most of whom have chronic pain. Charts with a diagnosis of low back pain were cross-referenced with an imaging database and any magnetic resonance imaging (MRI) of the lumbar spine with or without contrast were identified. RESULTS: Seventy-six of 137 patients referred to the HPCC were found to have back pain. These patients were mainly young (median age 45, interquartile range 40-51) with well-controlled HIV. Twenty-two (29%) of these patients had an MRI of the lumbar spine, and 11 (50%) of these warranted follow-up, most of whom had degenerative disc disease, including four with findings concerning for malignancy. DISCUSSION: This is the first study to explore the role of spinal imaging in HIV-infected patients. In our study, four patients had findings concerning for malignancy. These findings suggest that spinal imaging should be considered in the work up of HIV-infected patients with moderate to severe back pain.


Assuntos
Infecções por HIV/complicações , Dor Lombar/epidemiologia , Dor Lombar/terapia , Vértebras Lombares/cirurgia , Cuidados Paliativos , Adulto , Doença Crônica , Diagnóstico por Imagem , Feminino , Humanos , Dor Lombar/complicações , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
J Palliat Med ; 16(8): 934-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23477304

RESUMO

BACKGROUND: Many HIV-infected patients in the current treatment era have substantial symptom burden, but few HIV palliative care clinics have been described. Our objective was to describe the University of Alabama at Birmingham (UAB) HIV palliative care clinic (HPCC) and compare it to the overall HIV clinic. METHODS: We conducted a chart review of patients referred to the HPCC between April 2008 and June 2011. We evaluated the reason for referral and other issues addressed during palliative care visits. Patient Reported Outcome (PRO) data was used to assess depression (PHQ-9), anxiety (PHQ-A), and substance abuse (ASSIST). RESULTS: Among 124 patients, mean age was 44 (range 27-64), and median CD4 count was 352 cells/mm(3) (IQR 209-639). Depression (43, 35%), anxiety (40, 32%), and current 8 (7%) or prior 68 (56%) substance abuse occurred at higher rates than in the overall HIV clinic (p<0.05). Pain was the most common reason for referral (118, 95%); most was chronic (113, 90%) and included back pain (26, 21%) and neuropathic pain (15, 12%). Other problems commonly addressed by the palliative team included nonpain symptoms such as depression (39, 48%) and anxiety (17, 21%), insomnia (25, 30%), and constipation (26, 32%). CONCLUSIONS: This is the first description of a palliative care clinic embedded within an HIV primary care clinic in a developed country that sees patients at all stages of illness. Chronic pain and nonpain symptom management in patients with psychiatric and substance abuse comorbidities are important components of ambulatory palliative care for HIV-infected patients.


Assuntos
Infecções por HIV/psicologia , Ambulatório Hospitalar/organização & administração , Manejo da Dor/métodos , Cuidados Paliativos/psicologia , Adulto , Alabama , Ansiedade/diagnóstico , Ansiedade/psicologia , Ansiedade/terapia , Comorbidade , Depressão/diagnóstico , Depressão/psicologia , Depressão/terapia , Feminino , Infecções por HIV/terapia , Hospitais Universitários , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Ambulatório Hospitalar/normas , Cuidados Paliativos/métodos , Cuidados Paliativos/normas , Encaminhamento e Consulta , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/psicologia , Transtornos Relacionados ao Uso de Substâncias/terapia
11.
Mol Phylogenet Evol ; 67(2): 311-35, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23403226

RESUMO

Pyronemataceae is the largest and most heterogeneous family of Pezizomycetes. It is morphologically and ecologically highly diverse, comprising saprobic, ectomycorrhizal, bryosymbiotic and parasitic species, occurring in a broad range of habitats (on soil, burnt ground, debris, wood, dung and inside living bryophytes, plants and lichens). To assess the monophyly of Pyronemataceae and provide a phylogenetic hypothesis of the group, we compiled a four-gene dataset including one nuclear ribosomal and three protein-coding genes for 132 distinct Pezizomycetes species (4437 nucleotides with all markers available for 80% of the total 142 included taxa). This is the most comprehensive molecular phylogeny of Pyronemataceae, and Pezizomycetes, to date. Three hundred ninety-four new sequences were generated during this project, with the following numbers for each gene: RPB1 (124), RPB2 (99), EF-1α (120) and LSU rDNA (51). The dataset includes 93 unique species from 40 genera of Pyronemataceae, and 34 species from 25 genera representing an additional 12 families of the class. Parsimony, maximum likelihood and Bayesian analyses suggest that Pyronemataceae is paraphyletic due to the nesting of both Ascodesmidaceae and Glaziellaceae within the family. Four lineages with taxa currently classified in the family, the Boubovia, Geopyxis, Pseudombrophila and Pulvinula lineages, form a monophyletic group with Ascodesmidaceae and Glaziellaceae. We advocate the exclusion of these four lineages in order to recognize a monophyletic Pyronemataceae. The genus Coprotus (Thelebolales, Leotiomycetes) is shown to belong to Pezizomycetes, forming a strongly supported monophyletic group with Boubovia. Ten strongly supported lineages are identified within Pyronemataceae s. str. Of these, the Pyropyxis and Otidea lineages are identified as successive sister lineages to the rest of Pyronemataceae s. str. The highly reduced (gymnohymenial) Monascella is shown to belong to Pezizomycetes and is for the first time suggested to be closely related to the cleistothecial Warcupia, as a sister group to the primarily apothecial Otidea. None of the lineages of pyronemataceous taxa identified here correspond to previous families or subfamily classifications. Ancestral character state reconstructions (ASR) using a Bayesian approach support that the ancestors of Pezizomycetes and Pyronemataceae were soil inhabiting and saprobic. Ectomycorrhizae have arisen within both lineages A, B and C of Pezizomycetes and are suggested to have evolved independently seven to eight times within Pyronemataceae s. l., whereas an obligate bryosymbiotic lifestyle has arisen only twice. No reversals to a free-living, saprobic lifestyle have happened from symbiotic or parasitic Pyronemataceae. Specializations to various substrates (e.g. burnt ground and dung) are suggested to have occurred several times in mainly saprobic lineages. Although carotenoids in the apothecia are shown to have arisen at least four times in Pezizomycetes, the ancestor of Pyronemataceae s. str., excluding the Pyropyxis and Otidea lineages, most likely produced carotenoids, which were then subsequently lost in some clades (- and possibly gained again). Excipular hairs were found with a high probability to be absent from apothecia in the deepest nodes of Pezizomycetes and in the ancestor of Pyronemataceae s. str. True hairs are restricted to the core group of Pyronemataceae s. str., but are also found in Lasiobolus (Ascodesmidaceae), the Pseudombrophila lineage and the clade of Chorioactidaceae, Sarcoscyphaceae and Sarcosomataceae. The number of gains and losses of true hairs within Pyronemataceae s. str., however, remains uncertain. The ASR of ascospore guttulation under binary coding (present or absent) indicates that this character is fast evolving and prone to shifts.


Assuntos
Ascomicetos/genética , Evolução Molecular , Proteínas Fúngicas/genética , Filogenia , Teorema de Bayes , Carotenoides/genética , Núcleo Celular/genética , DNA Ribossômico/genética , Micorrizas/genética , Análise de Sequência de DNA , Simbiose
12.
Photochem Photobiol Sci ; 11(5): 848-52, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22495263

RESUMO

Since the early 20th century, many researchers have attempted to determine how fungi are able to emit light. The first successful experiment was obtained using the classical luciferin-luciferase test that consists of mixing under controlled conditions hot (substrate/luciferin) and cold (enzyme/luciferase) water extracts prepared from bioluminescent fungi. Failures by other researchers to reproduce those experiments using different species of fungi lead to the hypothesis of a non-enzymatic luminescent pathway. Only recently, the involvement of a luciferase in this system was proven, thus confirming its enzymatic nature. Of the 100,000 described species in Kingdom Fungi, only 71 species are known to be luminescent and they are distributed unevenly amongst four distantly related lineages. The question we address is whether the mechanism of bioluminescence is the same in all four evolutionary lineages suggesting a single origin of luminescence in the Fungi, or whether each lineage has a unique mechanism for light emission implying independent origins. We prepared hot and cold extracts of numerous species representing the four bioluminescent fungal lineages and performed cross-reactions (luciferin × luciferase) in all possible combinations using closely related non-luminescent species as controls. All cross-reactions with extracts from luminescent species yielded positive results, independent of lineage, whereas no light was emitted in cross-reactions with extracts from non-luminescent species. These results support the hypothesis that all four lineages of luminescent fungi share the same type of luciferin and luciferase, that there is a single luminescent mechanism in the Fungi, and that fungal luciferin is not a ubiquitous molecule in fungal metabolism.


Assuntos
Fungos/classificação , Fungos/metabolismo , Luminescência , Evolução Biológica , Proteínas Fúngicas/metabolismo , Luciferases/metabolismo , Substâncias Luminescentes/metabolismo , Proteínas Luminescentes/metabolismo , Modelos Biológicos , Filogenia
13.
Mycologia ; 103(6): 1433-40, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21700638

RESUMO

The bioluminescent agaric, Agaricus gardneri Berk., was rediscovered recently in central Brazil. The new combination, Neonothopanus gardneri, is proposed for this long-forgotten taxon supported by morphological and molecular data.


Assuntos
Agaricus/classificação , Agaricus/genética , Brasil , Medições Luminescentes , Filogenia
14.
PLoS One ; 5(7): e11815, 2010 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-20676400

RESUMO

Adenoviral (Ad) vectors have been used for a variety of vaccine applications including cancer and infectious diseases. Traditionally, Ad-based vaccines are designed to express antigens through transgene expression of a given antigen. However, in some cases these conventional Ad-based vaccines have had sub-optimal clinical results. These sub-optimal results are attributed in part to pre-existing Ad serotype 5 (Ad5) immunity. In order to circumvent the need for antigen expression via transgene incorporation, the "antigen capsid-incorporation" strategy has been developed and used for Ad-based vaccine development in the context of a few diseases. This strategy embodies the incorporation of antigenic peptides within the capsid structure of viral vectors. The major capsid protein hexon has been utilized for these capsid incorporation strategies due to hexon's natural role in the generation of anti-Ad immune response and its numerical representation within the Ad virion. Using this strategy, we have developed the means to incorporate heterologous peptide epitopes specifically within the major surface-exposed domains of the Ad capsid protein hexon. Our study herein focuses on generation of multivalent vaccine vectors presenting HIV antigens within the Ad capsid protein hexon, as well as expressing an HIV antigen as a transgene. These novel vectors utilize HVR2 as an incorporation site for a twenty-four amino acid region of the HIV membrane proximal ectodomain region (MPER), derived from HIV glycoprotein gp41 (gp41). Our study herein illustrates that our multivalent anti-HIV vectors elicit a cellular anti-HIV response. Furthermore, vaccinations with these vectors, which present HIV antigens at HVR2, elicit a HIV epitope-specific humoral immune response.


Assuntos
Vacinas contra a AIDS/imunologia , Adenoviridae/genética , Antígenos HIV/imunologia , Vacinas contra a AIDS/genética , Animais , Western Blotting , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Vetores Genéticos/genética , Anticorpos Anti-HIV/imunologia , Antígenos HIV/química , Antígenos HIV/genética , Proteína gp41 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/imunologia , Humanos , Imunidade Humoral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/síntese química , Peptídeos/química , Peptídeos/imunologia
15.
Mycologia ; 102(2): 459-77, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20361513

RESUMO

Seven species of Mycena are reported as luminescent, representing specimens collected in Belize, Brazil, Dominican Republic, Jamaica, Japan (Bonin Islands), Malaysia (Borneo) and Puerto Rico. Four of them represent new species (Mycena luxaeterna, M. luxarboricola, M. luxperpetua, M. silvaelucens) and three represent new reports of luminescence in previously described species (M. aff. abieticola, M. aspratilis, M. margarita). Mycena subepipterygia is synonymized with M. margarita, and M. chlorinosma is proposed as a possible synonym. Comprehensive descriptions, illustrations, photographs and comparisons with phenetically similar species are provided. A redescription of M. chlorophos, based on analyses of type specimens and recently collected topotypical material, is provided. The addition of these seven new or newly reported luminescent species of Mycena brings the total to 71 known bioluminescent species of fungi.


Assuntos
Agaricales/isolamento & purificação , Agaricales/fisiologia , Agaricales/ultraestrutura , Luminescência
16.
Plant Signal Behav ; 5(4): 349-53, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20061806

RESUMO

Mycoheterotrophic plants are achlorophyllous plants that obtain carbon from their mycorrhizal fungi. They are usually considered to associate with fungi that are (1) specific of each mycoheterotrophic species and (2) mycorrhizal on surrounding green plants, which are the ultimate carbon source of the entire system. Here we review recent works revealing that some mycoheterotrophic plants are not fungal-specific, and that some mycoheterotrophic orchids associate with saprophytic fungi. A re-examination of earlier data suggests that lower specificity may be less rare than supposed in mycoheterotrophic plants. Association between mycoheterotrophic orchids and saprophytic fungi arose several times in the evolution of the two partners. We speculate that this indirectly illustrates why transition from saprotrophy to mycorrhizal status is common in fungal evolution. Moreover, some unexpected fungi occasionally encountered in plant roots should not be discounted as 'molecular scraps', since these facultatively biotrophic encounters may evolve into mycorrhizal symbionts in some other plants.


Assuntos
Micorrizas/fisiologia , Orchidaceae/microbiologia , Simbiose , Evolução Biológica , Micorrizas/genética , Filogenia , Especificidade da Espécie
17.
Mycologia ; 101(4): 545-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19623935

RESUMO

A new lignicolous species of phalloid fungi, discovered recently on the western African island of São Tomé, is described as Phallus drewesii. A comprehensive description, photographs and comparison with phenetically similar species are provided.


Assuntos
Basidiomycota/classificação , África , Ecossistema , Especificidade da Espécie , Esporos Fúngicos
18.
Mycol Res ; 111(Pt 5): 549-71, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17572335

RESUMO

Partial sequences of nuLSU rDNA were obtained to investigate the phylogenetic relationships of Pyronemataceae, the largest and least studied family of Pezizales. The dataset includes sequences for 162 species from 51 genera of Pyronemataceae, and 39 species from an additional 13 families of Pezizales. Parsimony, ML, and Bayesian analyses suggest that Pyronemataceae is not monophyletic as it is currently circumscribed. Ascodesmidaceae is nested within Pyronemataceae, and several pyronemataceous taxa are resolved outside the family. Glaziellaceae forms the sister group to Pyronemataceae in ML analyses, but this relationship, as well as those of Pyronemataceae to the other members of the lineage, are not resolved with support. Fourteen clades of pyronemataceous taxa are well supported and/or present in all recovered trees. Several pyronemataceous genera are suggested to be non-monophyletic, including Anthracobia, Cheilymenia, Geopyxis, Humaria, Lasiobolidium, Neottiella, Octospora, Pulvinula, Stephensia, Tricharina, and Trichophaea. Cleistothecial and truffle or truffle-like ascomata forms appear to have evolved independently multiple times within Pyronemataceae. Results of these analyses do not support previous classifications of Pyronemataceae, and suggest that morphological characters traditionally used to segregate the family into subfamilial groups are not phylogenetically informative above the genus level.


Assuntos
Ascomicetos/classificação , Ascomicetos/genética , DNA Fúngico/genética , DNA Ribossômico/genética , Evolução Molecular , Genes Fúngicos , Fenótipo , Filogenia , Alinhamento de Sequência
19.
New Phytol ; 170(3): 581-96, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16626478

RESUMO

A growing body of molecular research is discovering a high diversity of pezizalean ectomycorrhiza (EcM), yet most remain unidentified at the genus or species level. This study describes EcM-forming taxa within the Pezizales. EcM-forming Pezizales were revealed by morphotyping and sequencing of EcM root tips from forests in Estonia and Denmark. The taxa on EcM root tips were identified using phylogenetic analyses of large-subunit rDNA sequences derived from sporocarps of 301 pezizalean species, and comparisons with internal transcribed spacer rDNA sequences. Thirty-three species are suggested as EcM symbionts, representing all three major clades of Pezizales, the genera Genea, Geopora, Humaria, Tarzetta, Trichophaea, Wilcoxina, Helvella, Hydnotrya, Tuber, Pachyphloeus, Peziza and Sarcosphaera, and two Pezizaceae anamorphs. EcM of Pezizales species are easily distinguished by their anatomy, particularly thick cell walls and stout hyphae. This study demonstrates that Pezizales species constitute a considerable proportion of the mycobionts in EcM fungal communities in mature boreal deciduous and coniferous forests, in several soil types. Fruit-body sequences and EcM descriptions will facilitate identification of pezizalean EcM in future studies.


Assuntos
Ascomicetos/classificação , Micorrizas/classificação , Ascomicetos/citologia , Ascomicetos/genética , Biodiversidade , DNA Ribossômico/genética , Dinamarca , Estônia , Micorrizas/citologia , Micorrizas/genética , Filogenia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/microbiologia , Análise de Sequência de DNA
20.
Dev Growth Differ ; 31(2): 157-164, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37282167

RESUMO

Proteins of the detergent-resistant cytoskeleton fraction and the detergent-soluble fraction from Xenopus oocytes and embryos are examined using a procedure which allows rapid and uniform extraction of tissues and large, single cells. SDS-polyacrylamide gels reveal only a few prominent cytoskeletal proteins in the early embryo, however qualitatively different proteins begin to appear after gastrulation. Incorporation of [35 S]-methionine into newly synthesized proteins indicates that there is synthesis and assembly of proteins into the cytoskeleton, but the amount remains low until after gastrulation. The use of nucleic acid probes for alpha-tubulin and actin mRNA indicates that about 80% of these mRNAs in the oocyte and meiotically mature egg are bound to the detergent-resistant cytoskeleton.

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