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1.
J Plant Res ; 133(3): 291-296, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32002717

RESUMO

The independent origin of roots in lycophytes and euphyllophytes has been proposed, mainly based on paleobotanical records. However, the question of how roots evolved within these lineages remains unresolved. Root apical meristem (RAM) organization in lycophytes would provide a clue toward understanding the early evolution of roots. Recently, we examined RAM organization in lycophytes (Lycopodiaceae, Isoetaceae, and Selaginellaceae) in terms of cell division activity and anatomy, comparing RAM among vascular plants. Lycophyte RAM exhibited four organization types (I, II, III, and apical); thus, RAM organization in extant lycophytes was more diverse than expected. Type I RAM contained a region with very low cell division frequency, reminiscent of the quiescent center (QC) in seed plant RAM. Although some euphyllophyte RAMs were structurally similar to types II and III and apical cell-type RAM, lycophyte RAM of types II and III had no QC-like area. These results support the paleobotanical predictions that roots evolved several times in lycophytes, as well as in euphyllophytes. In this review, we also introduce recent findings on RAM organization in extant lycophytes and discuss the origin of roots in vascular plants.


Assuntos
Lycopodiaceae/crescimento & desenvolvimento , Meristema/citologia , Raízes de Plantas/citologia , Evolução Biológica , Divisão Celular , Lycopodiaceae/citologia
2.
Nucleic Acids Res ; 48(5): 2661-2675, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-31915815

RESUMO

The occurrence of group II introns in plant mitochondrial genomes is strikingly different between the six major land plant clades, contrasting their highly conserved counterparts in chloroplast DNA. Their present distribution likely reflects numerous ancient intron gains and losses during early plant evolution before the emergence of seed plants. As a novelty for plant organelles, we here report on five cases of twintrons, introns-within-introns, in the mitogenomes of lycophytes and hornworts. An internal group II intron interrupts an intron-borne maturase of an atp9 intron in Lycopodiaceae, whose splicing precedes splicing of the external intron. An invasive, hypermobile group II intron in cox1, has conquered nine further locations including a previously overlooked sdh3 intron and, most surprisingly, also itself. In those cases, splicing of the external introns does not depend on splicing of the internal introns. Similar cases are identified in the mtDNAs of hornworts. Although disrupting a group I intron-encoded protein in one case, we could not detect splicing of the internal group II intron in this 'mixed' group I/II twintron. We suggest the name 'zombie' twintrons (half-dead, half-alive) for such cases where splicing of external introns does not depend any more on prior splicing of fossilized internal introns.


Assuntos
Íntrons/genética , Lycopodiaceae/genética , Mitocôndrias/genética , Sequência de Bases , Sequência Conservada/genética , Evolução Molecular , Hepatófitas/genética , Conformação de Ácido Nucleico , Filogenia , Terminologia como Assunto
3.
Fitoterapia ; 139: 104378, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31676395

RESUMO

Five previously undescribed lycodine-type alkaloids, named huperzine Y (1), 8,15-epoxy-N-demethylhuperzinine (2), 7-hydroxyl-huperzinine (3), huperzine Z (4), and huperzine D N-oxide (5), were isolated from the aerial parts and roots of Lycopodiastrum casuarinoides (Lycopodiaceae), along with ten known analogues. The structures of the new compounds were elucidated by means of spectroscopic technique (IR, UV, MS and NMR). The absolute configurations of the new compounds were established on the basis of comparison of their experimental and TD-DFT (time-dependent density functional theory) calculated ECD spectra. Moreover, all the isolates were evaluated for acetylcholinesterase (AChE) inhibitory activity. Only huperzine C showed moderate activity, with an IC50 value of 0.525 ±â€¯0.140 µM, which was comparable with the positive control, huperzine A (IC50 = 0.143 ±â€¯0.029 µM).


Assuntos
Alcaloides/farmacologia , Inibidores da Colinesterase/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Lycopodiaceae/química , Alcaloides/isolamento & purificação , China , Inibidores da Colinesterase/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Raízes de Plantas/química
4.
Genome Biol Evol ; 11(11): 3181-3193, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31633753

RESUMO

Transposable elements represent the largest components of many eukaryotic genomes and different genomes harbor different combinations of elements. Here, we discovered a novel DNA transposon in the genome of the clubmoss Selaginella lepidophylla. Further searching for related sequences to the conserved DDE region uncovered the presence of this superfamily of elements in fish, coral, sea anemone, and other animal species. However, this element appears restricted to Bryophytes and Lycophytes in plants. This transposon, named GingerRoot, is associated with a 6 bp (base pair) target site duplication, and 100-150 bp terminal inverted repeats. Analysis of transposase sequences identified the DDE motif, a catalytic domain, which shows similarity to the integrase of Gypsy-like long terminal repeat retrotransposons, the most abundant component in plant genomes. A total of 77 intact and several hundred truncated copies of GingerRoot elements were identified in S. lepidophylla. Like Gypsy retrotransposons, GingerRoots show a lack of insertion preference near genes, which contrasts to the compact genome size of about 100 Mb. Nevertheless, a considerable portion of GingerRoot elements was found to carry gene fragments, suggesting the capacity of duplicating gene sequences is unlikely attributed to the proximity to genes. Elements carrying gene fragments appear to be less methylated, more diverged, and more distal to genes than those without gene fragments, indicating they are preferentially retained in gene-poor regions. This study has identified a broadly dispersed, novel DNA transposon, and the first plant DNA transposon with an integrase-related transposase, suggesting the possibility of de novo formation of Gypsy-like elements in plants.


Assuntos
Briófitas/genética , Elementos de DNA Transponíveis , Evolução Molecular , Lycopodiaceae/genética , Transposases/genética , Animais , Integrases , Filogenia , Plantas
5.
Fitoterapia ; 139: 104366, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31629868

RESUMO

Phytochemical investigation of the ethyl acetate extract of Lycopodiastrum casuarinoides (Spring) Holub (Lycopodiaceae) led to the isolation of nine compounds, including two new serratene triterpenoids, serrat-14-en-3α,21α-diol (1), 26-nor-8-oxo-21-one-α-onocerin (6), one new abietane diterpenoid, lycocasuarinone A (7), one new sesquiterpene acid, 7, 9-diene-1,4-epoxy-2-hydroxy-10-carboxylic acid (8) and one new chromone derivative, 5,7-dihydroxy-2-methyl esterchromone (9), together with four known serratene triterpenoids (2-5). Abietane diterpenoid (7) and sesquiterpene acid (8) from Lycopodiastrum casuarinoides are reported for the first time. Their structures and stereochemistry were unambiguously elucidated by spectroscopic analysis and comparison with known ones. All the compounds were tested for acetylcholinesterase (AChE) and butyrocholinesterase (BuChE) inhibitory activities. Bioactivity assays revealed that compound 6 exhibited the most potent AChE inhibitory effect.


Assuntos
Abietanos/farmacologia , Inibidores da Colinesterase/farmacologia , Lycopodiaceae/química , Sesquiterpenos/farmacologia , Triterpenos/farmacologia , Abietanos/isolamento & purificação , China , Inibidores da Colinesterase/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Sesquiterpenos/isolamento & purificação , Triterpenos/isolamento & purificação
6.
J Plant Res ; 132(6): 719-721, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31595362

RESUMO

The past quarter-century has witnessed a revolution in our understanding of the phylogenetics, systematics, and ecology of pteridophytes (ferns and lycophytes), particularly due to the rapid accumulation of plastid sequence data and a renewed interest in the ecology of the sexual phase of the life cycle. We here compile 19 papers recently published in the Journal of Plant Research dealing with the biology of pteridophytes, grouped into six categories: (1) breeding systems, (2) species complexes and polyploidization, (3) fossil taxa, (4) gametophyte ecology, (5) systematics, (6) biodiversity. We hope this collection of papers will be of value to researchers interested in this fascinating group of plants.


Assuntos
Evolução Biológica , Gleiquênias/fisiologia , Traços de História de Vida , Lycopodiaceae/fisiologia , Selaginellaceae/fisiologia , Evolução Molecular , Gleiquênias/classificação , Gleiquênias/genética , Lycopodiaceae/classificação , Lycopodiaceae/genética , Selaginellaceae/classificação , Selaginellaceae/genética
7.
J Plant Res ; 132(6): 723-738, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31529289

RESUMO

The fern and lycophyte flora of Japan comprising 721 native taxa (including subspecies and varieties) plus 371 interspecific hybrids was reassessed using a nearly comprehensively sampled distribution map at 10 km resolution vouchered by 216,687 specimens, up-to-date cytotaxonomic information covering 74% of the taxa, and an rbcL sequence dataset covering 97.9% of the taxa. Spatial distribution of species richness and phylogenetic diversity was visualized. Apomixis was observed in 11.0% of the native taxa whose reproductive modes are known. The number of sexually reproducing polyploid taxa (n = 199) is less than sexual diploids (n = 241), and 30 of them are evidently allopolyploid, in contrast with the low number of possible autopolyploids (n = 4). Apomictic taxa were found to have smaller latitudinal ranges than sexual taxa or taxa with multiple reproductive modes. A morphological character dataset in Lucid format is provided for taxonomic identification of the native taxa.


Assuntos
Gleiquênias/fisiologia , Lycopodiaceae/fisiologia , Selaginellaceae/fisiologia , Biodiversidade , DNA de Plantas , Evolução Molecular , Gleiquênias/classificação , Gleiquênias/genética , Japão , Lycopodiaceae/classificação , Lycopodiaceae/genética , Selaginellaceae/classificação , Selaginellaceae/genética
8.
J Ethnopharmacol ; 245: 112130, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31376517

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The most speciose subfamily Huperzioideae (Lycopodiaceae, Lycopodiophyta) contains about 276 species, and some (ca. 20 species) have traditionally been used for the treatment of e.g., dementia, rheumatism and traumatic injury. Ethnopharmacological studies have also contributed to the development of huperzine A as a drug lead, a compound first isolated from the club moss Huperzia serrata (Thunb. ex Murray) Trevis. AIM OF THE REVIEW: This review, with a phylogenetic and chemosystematic perspective, intends to highlight plant identification challenges in these taxa with examples from club moss phytochemical and ethnopharmacological studies, as these lead to data inconsistency and confusion. We suggest that future studies should include more details on plant identification including for example plant specimen images and DNA barcoding data. An integrative approach combining DNA barcoding and chemical fingerprinting is also introduced. MATERIALS AND METHODS: Literature concerning ethnopharmacology and chemosystematics of Huperzioideae club mosses was searched from databases, e.g. PubMed, Web of Science, SciFinder, etc. Plant names were retrieved from original publications, and compared with up-to-date taxonomic and phylogenetic status. Ethnobotanical uses and herbal preparations were summarized. Production of certain pharmaceutically interesting compounds, such as the alkaloid huperzine A, was explored in a phylogenetic context. RESULTS: Most traditionally used club mosses are associated with psychoactivity, followed by medicinal uses against rheumatism and traumatic injury. Herbs are often prepared as infusions, decoctions or tinctures, and this implies importance of water- or aqueous-alcohol-soluble substances, such as alkaloids. Most ethnopharmacological papers on club mosses need to update or correct plant names according to recent taxonomic nomenclature, and there are still a number of unidentified species with traditional use. Advanced LC-MS chemical profiling techniques, enable distinction of genotypes of the same species as well as annotation of potential chemotaxonomic markers. In combination with DNA barcoding, chemosystematics could also help us select plant taxa with higher pharmaceutical potential. Caution should be taken when interpreting bioassay results, in terms of compounds or extract preparation and bioassay standardization. CONCLUSION: Huperzioideae club mosses have interesting pharmaceutical potential supported by ethnopharmacological investigations. Bioprospecting of these plants should be preceded by careful plant identification to produce consistent and reproducible data. We expect that DNA barcoding and LC-MS-based chemical fingerprinting could facilitate and improve ethnopharmaceutical studies in selection of club moss taxa.


Assuntos
Lycopodiaceae , Etnofarmacologia , Lycopodiaceae/química , Lycopodiaceae/genética , Filogenia , Compostos Fitoquímicos/análise
9.
Fitoterapia ; 136: 104181, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31145984

RESUMO

The plants of Lycopodiaceae family, distributed across China, India and also Southeast Asia, have been used as folk medicines. The phytochemical constitutent studies of this family was widely reported. Serratene trierpenoids is one of phytochemical constitutent type, which have been mainly isolated from this plant family. To date, more than 100 serratene-type triterpenoids have been reported and several of them have been shown promising biological activities, especially cytotoxicity and chemopreventive activity. This review covers the structural classification, biological activities and hypotheses about biosynthetic pathways of serratene-type triterpenes.


Assuntos
Lycopodiaceae/química , Triterpenos/farmacologia , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Triterpenos/química
10.
Fitoterapia ; 134: 474-480, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30923010

RESUMO

Lycocasuarines I-Q (1-9), nine new lycodine-type Lycopodium alkaloids were isolated from the aerial parts of Lycopodiastrum casuarinoides (Spring) Holub ex R.D.Dixit. Their structures were unambiguously determined via extensive spectroscopic analyses, including HRESIMS, NMR, and electronic circular dichroism (ECD). The new alkaloids were evaluated for their in vitro inhibitory activity against acetylcholinesterase (AChE). Compounds 3, 5-8 exhibited marginal or weak activities with IC50 values ranging from 97.2 to 171.9 µM.


Assuntos
Alcaloides/farmacologia , Inibidores da Colinesterase/farmacologia , Lycopodiaceae/química , Alcaloides/isolamento & purificação , China , Inibidores da Colinesterase/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química
11.
12.
New Phytol ; 222(3): 1256-1270, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30623444

RESUMO

Photosynthesis in bryophytes and lycophytes has received less attention than terrestrial plant groups. In particular, few studies have addressed the nonstomatal diffusion conductance to CO2 gnsd of these plant groups. Their lower photosynthetic rate per leaf mass area at any given nitrogen concentration compared with vascular plants suggested a stronger limitation by CO2 diffusion. We hypothesized that bryophyte and lycophyte photosynthesis is largely limited by low gnsd . Here, we studied CO2 diffusion inside the photosynthetic tissues and its relationships with photosynthesis and anatomical parameters in bryophyte and lycophyte species in Antarctica, Australia, Estonia, Hawaii and Spain. On average, lycophytes and, specially, bryophytes had the lowest photosynthetic rates and nonstomatal diffusion conductance reported for terrestrial plants. These low values are related to their very thick cell walls and their low exposure of chloroplasts to cell perimeter. We conclude that the reason why bryophytes lie at the lower end of the leaf economics spectrum is their strong nonstomatal diffusion conductance limitation to photosynthesis, which is driven by their specific anatomical characteristics.


Assuntos
Briófitas/anatomia & histologia , Briófitas/fisiologia , Lycopodiaceae/anatomia & histologia , Lycopodiaceae/fisiologia , Fotossíntese , Estômatos de Plantas/anatomia & histologia , Estômatos de Plantas/fisiologia , Biomassa , Difusão , Geografia , Filogenia
13.
Environ Entomol ; 48(1): 53-60, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30561603

RESUMO

Fern-insect interactions have not received the same attention as angiosperm-insect interactions have. It has even been stated that ferns may have very few interactions with animals because of their lack of flowers, fruits, and seeds. Consequently, for many decades fern-insect interactions have been overlooked and underestimated, especially for highly developed interactions such as those with gall-formers. The present work aims to review the galls of ferns and lycophytes worldwide, to provide an updated checklist including unpublished data and to estimate the global gall diversity of ferns and lycophytes. We recorded 93 host species, belonging to 41 genera. Galls were found in 20 fern families and one lycophyte family (Selaginellaceae). Most galls occur within the more derived ferns of the order Polypodiales, especially the fern families Polypodiaceae (21 host species), Dryopteridaceae (14 host species) and Athyriaceae (11 host species). Thirty-eight of the 133 gall morphotypes were induced by mites and 95 by insects of six orders (Coleoptera, Diptera, Hymenoptera, Lepidoptera, Thysanoptera, and Hemiptera). Among the insects, Cecidomyiidae (Diptera) caused most of the galls (35 morphotypes). So far, most galls have been reported from the Neotropical region (40 spp.) and Oriental region (28 spp.).


Assuntos
Biodiversidade , Gleiquênias/parasitologia , Lycopodiaceae/parasitologia , Tumores de Planta , Animais , Insetos , Ácaros
14.
New Phytol ; 222(2): 1061-1075, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30556907

RESUMO

Lycophytes are a key group for understanding vascular plant evolution. Lycophyte plastomes are highly distinct, indicating a dynamic evolutionary history, but detailed evaluation is hindered by the limited availability of sequences. Eight diverse plastomes were sequenced to assess variation in structure and functional content across lycophytes. Lycopodiaceae plastomes have remained largely unchanged compared with the common ancestor of land plants, whereas plastome evolution in Isoetes and especially Selaginella is highly dynamic. Selaginella plastomes have the highest GC content and fewest genes and introns of any photosynthetic land plant. Uniquely, the canonical inverted repeat was converted into a direct repeat (DR) via large-scale inversion in some Selaginella species. Ancestral reconstruction identified additional putative transitions between an inverted and DR orientation in Selaginella and Isoetes plastomes. A DR orientation does not disrupt the activity of copy-dependent repair to suppress substitution rates within repeats. Lycophyte plastomes include the most archaic examples among vascular plants and the most reconfigured among land plants. These evolutionary trends correlate with the mitochondrial genome, suggesting shared underlying mechanisms. Copy-dependent repair for DR-localized genes indicates that recombination and gene conversion are not inhibited by the DR orientation. Gene relocation in lycophyte plastomes occurs via overlapping inversions rather than transposase/recombinase-mediated processes.


Assuntos
Composição de Bases/genética , Genes de Plantas , Variação Genética , Genomas de Plastídeos , Íntrons/genética , Sequências Repetidas Invertidas/genética , Lycopodiaceae/genética , RNA Ribossômico/genética , Evolução Molecular , Dosagem de Genes , Tamanho do Genoma , Filogenia , Selaginellaceae/genética
15.
Ann Bot ; 123(1): 145-152, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107388

RESUMO

Background and Aims: Structures that simultaneously perform many functional roles are likely to show a variety of morphological solutions to these demands, and thus probably exhibit high morphological disparity. In contrast, specialization for a few simple functions should result in a more limited suite of morphologies. We explore this idea using lycopsid reproductive structures, which, throughout their history, have performed a limited set of functional roles compared with the reproductive structures of other plant groups such as seed plants. Methods: We scored living and fossil lycopsid taxa for 18 discrete character measurements and several continuous traits, including sporangium size, supporting axis diameter, and strobilus length and width. We used the discrete characters to construct a multivariate morphospace for lycopsid reproductive morphology through time, and the continuous characters to test whether fossil and extant lycopsids show similar patterns of tissue allocation within reproductive structures. Results: Lycopsids occupy similar areas of reproductive morphospace and show similar patterns of tissue allocation over most of their history, alternating between diffuse fertile zones with leaf-like sporophylls and compact strobili with specialized sporophylls that allow sporangia to be closely packed while also protected during their development. Growth habit also plays an important role in lycopsid reproductive evolution, broadly influencing the size and shape of reproductive structures. Conclusions: Lycopsid reproductive structures are primarily specialized for densely packaging sporangia, and are consistent with the idea that performing limited functional roles is associated with reduced morphological disparity. Morphologies similar to lycopsid strobili are also found in other groups with simple, wind-dispersed propagules, suggesting that the same processes occur across plant lineages.


Assuntos
Evolução Biológica , Fósseis/anatomia & histologia , Esporângios/anatomia & histologia , Traqueófitas/anatomia & histologia , Lycopodiaceae/anatomia & histologia , Estruturas Vegetais/anatomia & histologia , Selaginellaceae/anatomia & histologia
16.
Braz J Biol ; 79(3): 495-504, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30304255

RESUMO

Forest edges typically exhibit higher luminosity and lower humidity than the forest interior, resulting in an abiotic gradient. However, the degree of abiotic difference can be affected from the type of the matrix, influencing the selection of species. We compared the floristic and phytosociological structure of understory communities of ferns and lycophytes of the edge and interior of three forest sites influenced by different types of surrounding matrices (natural field, Pinus plantation, and cultivation of crops). In the region of Araucaria Forest, in Rio Grande do Sul, Brazil, twelve 10 × 10 m plots were selected at the edge and interior of each site, totaling 72 plots and to evaluate the phytosociological contrast, using as a parameter coverage and species richness per plot to evaluate this contrast. We recorded a total of 38 species in the studied areas, distributed in 15 families. The results show that the edge effect acts at different intensities in the analyzed sites. In the site with unnatural matrix, the composition was more homogeneous both in the edges and in the interiors and presented lower richness, showing a more pronounced and deep impact. Already in the site with natural matrix surroundings, although the border also presents low richness, the interior was about 3x richer. Based on our results, we concluded that fern conservation efforts should focus on fragments of Araucaria Forest inserted in the natural field, because the conversion of natural field into Pinus planting and cultivation of crops decreases ferns species both in the edges and forest interiors of the studied fragments, besides altering the phytosociological structure leading the communities to simplification.


Assuntos
Biota , Gleiquênias , Florestas , Lycopodiaceae , Brasil
17.
New Phytol ; 222(1): 604-613, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30326543

RESUMO

Tropical mountains are disproportionately biodiverse relative to their surface area, but the processes underlying their exceptional diversity require further study. Here, we use comparative phylogenetic methods to examine the impact of the Andean orogeny on the diversification of Neotropical Phlegmariurus, a species-rich lycophyte clade. We generated a time-calibrated phylogeny of 105 species of Neotropical Phlegmariurus and estimated lineage diversification rates. We tested for correlations between lineage diversification rates and species range size, niche breadth, elevational range amplitude, and mean elevation of occurrence. A recently developed macroevolutionary model was used to incorporate geological data and test for an association between diversification rates and the Andean uplift. Diversification rates of Neotropical Phlegmariurus are negatively correlated with species range size and positively correlated with mean elevation of species occurrence. The rise of the Andes is strongly associated with increased rates of diversification in Neotropical Phlegmariurus during the last 10 Myr. Our study demonstrates the importance of mountain-building events and geographical isolation of alpine populations as drivers of rapid diversification, even in spore-dispersed plants. This work also highlights the usefulness of combined phylogenetic, geological and ecological datasets, and the promise of comparative environment-dependent diversification models in better understanding the evolutionary origins of biodiversity.


Assuntos
Biodiversidade , Ecossistema , Lycopodiaceae/fisiologia , Clima Tropical , Altitude , Paleontologia , Filogenia
18.
Mol Phylogenet Evol ; 131: 181-192, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30415022

RESUMO

In Europe, the genus Diphasiastrum (Lycopodiophyta) forms a reticulate network of six diploid taxa, including three parent species (D. alpinum, D. complanatum and D. tristachyum) and three hybrids (D. × issleri, D. × oellgaardii and D. × zeilleri). It was not clear if the hybrids arose once or repeatedly, if they have reproductive competence and if backcrossing occurs. We addressed these questions by analysing 209 accessions for chloroplast microsatellites (cp), two nuclear markers (introns of the RPB and LFY genes) and AFLP. For D. complanatum we show a sexual life cycle with alternation of generations: the gametophytic DNA amount is half of that of the sporophyte. With the exception of a single accession all hybrids display one of the two parental cp haplotypes; their frequencies do not differ significantly from a 1:1 ratio. Genotypes of nuclear markers are species-specific, displaying 2/4/1 (RPB) and 1/8/1 alleles (LFY) for the three parents mentioned above; all hybrids have one allele from each parent. All three hybrid taxa apparently represent independent F1 crosses. Hybridisation occurs bidirectional; no evidence for recent backcrossing was found. Asexual reproduction via agamospory is at least rare, since AFLP showed all hybrid plants to be different.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Núcleo Celular/genética , Variação Genética , Hibridização Genética , Lycopodiaceae/genética , Repetições de Microssatélites/genética , Alelos , Briófitas , Cloroplastos/genética , Europa (Continente) , Marcadores Genéticos , Haplótipos , Íntrons/genética , Filogenia , Análise de Componente Principal , Reprodução/genética
19.
Fitoterapia ; 131: 86-90, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30352296

RESUMO

A chemical investigation on the 70% EtOH extract of the aerial parts of Lycopodiastrum casuarinoides led to the isolation of six novel lycodine type alkaloids, lycocasuarines A-F (1-6). The structures of the isolated compounds were established based on 1D and 2D (1H1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated alkaloids were tested in vitro for cytotoxic potentials against seven malignant melanoma cell lines as well as acetylcholinesterase (AChE) and butyrocholinesterase (BuChE) inhibitory activities. As a result, alkaloids 1 and 3 exhibited significant cytotoxic activities against all the tested tumor cell lines with IC50 values <10 µM and the inhibitory activities for AchE (0.94 ±â€¯0.15 and 0.24 ±â€¯0.03 µM, respectively) and BuchE (1.82 ±â€¯0.12 and 7.31 ±â€¯0.42 µM, respectively).


Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Inibidores da Colinesterase/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Lycopodiaceae/química , Acetilcolinesterase , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Butirilcolinesterase , Linhagem Celular Tumoral , Inibidores da Colinesterase/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química
20.
Phytochemistry ; 156: 83-88, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30237134

RESUMO

Phytochemical constituents in alkaloid extracts from three Thai club mosses Huperzia squarrosa, Huperzia phlegmaria and Phlegmariurus nummularifolius were investigated. Squarrosinoxide was an undescribed Lycopodium alkaloid from H. squarrosa possessing an unprecedented 6/5/7 tricyclic spiro system. Acetyllycophlegmarianol was an undescribed N-oxide lycopodine-type alkaloid isolated from H. phlegmaria. 4-Epilycopodine, an undescribed epimer of lycopodine, was first isolated from P. nummularifolius. The structural assignments were established through comprehensive spectroscopic techniques and chemical correlations. All compounds were assayed for their anti-acetylcholinesterase activity in vitro.


Assuntos
Acetilcolinesterase/metabolismo , Alcaloides/farmacologia , Inibidores da Colinesterase/farmacologia , Lycopodiaceae/química , Lycopodium/química , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Electrophorus , Conformação Molecular , Tailândia
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