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1.
Mol Phylogenet Evol ; 79: 132-68, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24747130

RESUMO

The Lecanoromycetes is the largest class of lichenized Fungi, and one of the most species-rich classes in the kingdom. Here we provide a multigene phylogenetic synthesis (using three ribosomal RNA-coding and two protein-coding genes) of the Lecanoromycetes based on 642 newly generated and 3329 publicly available sequences representing 1139 taxa, 317 genera, 66 families, 17 orders and five subclasses (four currently recognized: Acarosporomycetidae, Lecanoromycetidae, Ostropomycetidae, Umbilicariomycetidae; and one provisionarily recognized, 'Candelariomycetidae'). Maximum likelihood phylogenetic analyses on four multigene datasets assembled using a cumulative supermatrix approach with a progressively higher number of species and missing data (5-gene, 5+4-gene, 5+4+3-gene and 5+4+3+2-gene datasets) show that the current classification includes non-monophyletic taxa at various ranks, which need to be recircumscribed and require revisionary treatments based on denser taxon sampling and more loci. Two newly circumscribed orders (Arctomiales and Hymeneliales in the Ostropomycetidae) and three families (Ramboldiaceae and Psilolechiaceae in the Lecanorales, and Strangosporaceae in the Lecanoromycetes inc. sed.) are introduced. The potential resurrection of the families Eigleraceae and Lopadiaceae is considered here to alleviate phylogenetic and classification disparities. An overview of the photobionts associated with the main fungal lineages in the Lecanoromycetes based on available published records is provided. A revised schematic classification at the family level in the phylogenetic context of widely accepted and newly revealed relationships across Lecanoromycetes is included. The cumulative addition of taxa with an increasing amount of missing data (i.e., a cumulative supermatrix approach, starting with taxa for which sequences were available for all five targeted genes and ending with the addition of taxa for which only two genes have been sequenced) revealed relatively stable relationships for many families and orders. However, the increasing number of taxa without the addition of more loci also resulted in an expected substantial loss of phylogenetic resolving power and support (especially for deep phylogenetic relationships), potentially including the misplacements of several taxa. Future phylogenetic analyses should include additional single copy protein-coding markers in order to improve the tree of the Lecanoromycetes. As part of this study, a new module ("Hypha") of the freely available Mesquite software was developed to compare and display the internodal support values derived from this cumulative supermatrix approach.


Assuntos
Ascomicetos/classificação , Filogenia , Ascomicetos/genética , Núcleo Celular/genética , Genes Fúngicos , Genes Mitocondriais , Funções Verossimilhança , Modelos Genéticos , RNA Ribossômico/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Software
2.
Sci Rep ; 14(1): 19682, 2024 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-39181961

RESUMO

The analysis of the interaction between main bionts (mycobiont and photobiont) in the lichen symbiosis delivers substantial information about their preferences in the selection of symbiotic partners, and their ecological preferences. The selectivity in the Parmelia genus has been defined as strong so far. However, data on this lichen genus, which includes several widely distributed species, are biogeographically limited. Therefore, using specialization indicators and extended sampling, in this study, we estimated the interactions between the main bionts of selected Parmelia spp., using two levels of estimation (species/OTU and haplotype). A comparison of mycobiont-photobiont interactions at different levels showed that considering only mycobiont species and Trebouxia OTUs, greater specialization is found, while Parmelia species studied in this work present a more generalistic strategy in photobiont choice when haplotypes are considered. Despite the uneven sampling of Parmelia species, the interpretation of specialization within species and individuals of the genus leads to a more precise and accurate interpretation of their adaptation strategies. Furthermore, the data from P. sulcata indicate the existence of a different pool of compatible haplotypes in some geographical regions compared to neighboring areas. This observation suggests the potential influence of climatic factors.


Assuntos
Haplótipos , Líquens , Simbiose , Simbiose/genética , Líquens/genética , Líquens/microbiologia , Líquens/fisiologia , Parmeliaceae/genética , Filogenia
3.
Biol Futur ; 70(3): 218-239, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34554446

RESUMO

BACKGROUND AND AIMS: Betony (Betonica officinalis L.) is one of the rarest and most spectacular plants in the Scandinavian flora. A long-term question has been whether it is spontaneous or introduced, or whether it comprises both spontaneous and introduced populations. This study aimed to answer this question by analyzing sequence data from the nuclear external transcribed spacer (ETS) region and three regions of the plastid genome, the trnT-trnL intergenic spacer (IGS) region, tRNA-Leu (trnL) intron, and the trnS-trnG IGS. MATERIALS AND METHODS: Altogether 41 samples from 11 European countries were analyzed. A unique duplication in the trnT-trnL IGS was detected in material from Skåne (southern Sweden), the "Skåne-duplication." Populations with this duplication are united on a moderately supported branch in the phylogeny based on plastid sequences. A distinct heath genotype from Yorkshire was discovered in the phylogeny based on plastid sequences and in a comparative cultivation. RESULTS: Phylogeny based on ETS sequences does not support any Scandinavian group, whereas a principal coordinates analysis ordination based on variable ETS positions indicated a spontaneous origin for all Scandinavian populations, which comprise a genetically well-defined subgroup of the species, most closely related to other spontaneous populations from adjacent parts of continental parts of northern Europe. DISCUSSION: Seven possible naturally occurring localities remain in Scandinavia, five in central Skåne, southernmost Sweden, and two on the southwestern part of the Danish island of Lolland.

4.
Cladistics ; 18(3): 237-278, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34911250

RESUMO

Phylogenetic relationships within the genus Cladonia, including Cladina (Cladoniaceae, Lecanoromycetes), were reconstructed based upon simultaneous analyses of DNA sequences and morphological and chemical data. We used sequences from the internal transcribed spacer 1 (ITS1), the 5.8 rDNA gene, and the internal transcribed spacer 2 (ITS2) of the nuclear rDNA gene cluster, and partial sequences from the protein-coding ß-tubulin gene. The analyses included 235 specimens of 168 taxa representing all currently recognized sections of Cladonia and Cladina and the outgroup genera Cladia, Pycnothelia, and Ramalea. Analyses were performed using optimization alignment with three different parameter values. The results of all analyses support the inclusion of Cladina in Cladonia. The current sectional division of Cladonia was not supported, and a new provisional classification for the genus is proposed.

5.
New Phytol ; 173(3): 621-629, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17244057

RESUMO

Here, cyanobiont selectivity of epiphytic lichen species was examined in an old growth forest area in Finland. Samples of the eight lichen species were collected from the same aspen (Populus tremula) and adjacent aspens in the same stand. The cyanobionts of these samples were compared with free and symbiotic Nostoc obtained from other habitats and geographic regions. Our results, based on the phylogenetic analysis of a partial small subunit of the ribosomal DNA (16S rDNA) and the rbcLX gene complex did not show any correlation with the geographic origin of the samples at any spatial scale. Instead, there was a correlation between the cyanobionts and the alleged taxonomy of their mycobionts. The results indicate that the lichen species examined are highly selective towards their cyanobiont partners. Only Lobaria pulmonaria proved to be more flexible, being able to associate with a wide range of Nostoc. A same Nostoc strain was found to form associations with taxonomically unrelated lichens indicating that the cyanobiont-mycobiont associations as a whole were not highly specific in the examined species.


Assuntos
Líquens/fisiologia , Populus/fisiologia , Simbiose , Árvores/fisiologia , DNA Ribossômico/genética , Finlândia , Genes de Plantas , Filogenia , Populus/crescimento & desenvolvimento , Especificidade da Espécie , Árvores/crescimento & desenvolvimento
6.
Mol Phylogenet Evol ; 27(1): 58-69, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12679071

RESUMO

Phylogenetic relationships and levels of geographic differentiation of two closely related bipolar taxa, Cladonia arbuscula and Cladonia mitis, were cladistically examined with ITS regions, SSU rDNA introns, partial beta-tubulin, and partial glyceraldehyde 3-phosphate dehydrogenase (GAPDH) genes. In the combined analysis of the four genes, C. arbuscula was paraphyletic, while C. mitis, nested within C. arbuscula, formed a strongly supported monophyletic group. C. arbuscula samples were divided into three separate clades: "arbuscula I," appearing as basal to the other ingroup taxa, "arbuscula II," and "arbuscula III" (the latter represented by only one specimen), which were not correlated with any morphological trait. Only C. mitis specimens formed a morphologically and chemically distinct group. None of the main clades was correlated with geographic origin. The separate analyses were poorly resolved, and in most cases samples from "arbuscula I," "arbuscula II," and "arbuscula III" clades were intermixed. An incongruence test revealed conflict among the four gene regions in almost all cases. Only ITS regions and introns were not significantly incongruent, suggesting lack of recombination within the ribosomal DNA locus. Incomplete lineage sorting and recombination were considered to be the main reasons accounting for the incongruencies. The high proportion of shared polymorphisms between the "arbuscula I" and "arbuscula II" clades, especially found from the beta-tubulin gene and from the ITS regions, and the lack of corroborating morphological characters both indicate a short history of reproductive isolation among the groups. The lack of genetic differentiation among the northern and southern samples within the main clades indicates a relatively recent gene flow, which may have resulted from migrations during the Pleistocene glaciations or from more recent long-distance dispersal.


Assuntos
Ascomicetos/classificação , Filogenia , Ascomicetos/genética , Sequência de Bases , Geografia , Dados de Sequência Molecular , Análise de Sequência de DNA
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