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1.
Sci Rep ; 12(1): 9145, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650209

RESUMO

The Pteris fauriei group (Pteridaceae) has a wide distribution in Eastern Asia and includes 18 species with similar but varied morphology. We collected more than 300 specimens of the P. fauriei group and determined ploidy by flow cytometry and inferred phylogenies by molecular analyses of chloroplast and nuclear DNA markers. Our results reveal a complicated reticulate evolution, consisting of seven parental taxa and 58 hybrids. The large number of hybrid taxa have added significant morphological complexity to the group leading to difficult taxonomic issues. The hybrids generally had broader ranges and more populations than their parental taxa. Genetic combination of different pairs of parental species created divergent phenotypes of hybrids, exhibited by both morphological characteristics and ecological fidelities. Niche novelty could facilitate hybrid speciation. Apogamy is common in this group and potentially contributes to the sustainability of the whole group. We propose that frequent hybridizations among members of the P. fauriei group generate and maintain genetic diversity, via novel genetic combinations, niche differentiation, and apogamy.


Assuntos
Pteridaceae , Pteris , Variação Genética , Hibridização Genética , Filogenia
2.
Am J Bot ; 109(5): 821-850, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35568966

RESUMO

PREMISE: The taxonomic status of Wright's cliff brake fern, Pellaea wrightiana, has been in dispute ever since it was first described by Hooker in 1858. Previously published evidence suggested that this "taxon" may represent a polyploid complex rather than a single discrete species, a hypothesis tested here using a multifaceted analytical approach. METHODS: Data derived from cytogenetics, spore analyses, leaf morphometrics, enzyme electrophoresis, and phylogenetic analyses of plastid and nuclear DNA sequences are used to elucidate the origin, relationships, and taxonomic circumscription of P. wrightiana. RESULTS: Plants traditionally assigned to this taxon represent three distinct polyploids. The most widespread, P. wrightiana, is a fertile allotetraploid that arose through hybridization between two divergent diploid species, P. truncata and P. ternifolia. Sterile triploids commonly identified as P. wrightiana, were found to be backcross hybrids between this fertile tetraploid and diploid P. truncata. Relatively common across Arizona and New Mexico, they are here assigned to P. ×wagneri hyb. nov. In addition, occasional sterile tetraploid plants assigned to P. wrightiana are shown here to be hybrids between the fertile allotetraploid and the tetraploid P. ternifolia subsp. arizonica. These tetraploid hybrids originated independently in two regions of parental sympatry (southern Arizona and west Texas) and are here assigned to P. ×gooddingii hyb. nov. CONCLUSIONS: Weaving together data from a diversity of taxonomic approaches, we show that plants identified as P. wrightiana represent three morphologically distinguishable polyploids that have arisen through repeated hybridization events involving the divergent sexual taxa P. ternifolia and P. truncata.


Assuntos
Pteridaceae , Tetraploidia , Filogenia , Poliploidia
3.
Elife ; 112022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35311640

RESUMO

The fern Ceratopteris richardii has been studied as a model organism for over 50 years because it is easy to grow and has a short life cycle. In particular, as the first homosporous vascular plant for which genomic resources were developed, C. richardii has been an important system for studying plant evolution. However, we know relatively little about the natural history of C. richardii. In this article, we summarize what is known about this aspect of C. richardii, and discuss how learning more about its natural history could greatly increase our understanding of the evolution of land plants.


Assuntos
Gleiquênias , Pteridaceae , Gleiquênias/genética , Genômica , Plantas/genética
4.
Microsc Res Tech ; 85(2): 487-498, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34467588

RESUMO

Scanning electron microscopy (SEM) was used to characterize spore morphology of 24 taxa of the subfamily Pteridoideae C. Chr. ex Crabbe, Jermy & Mickel of the family Pteridaceae E.D.M. Kirchn. The family is considered to be one of the most taxonomically confusing families due to its high level of polymorphism. The standardized data on spore morphology of the subfamily Pteridoideae were projected onto the final phylogenetic tree in the Mesquite program. This approach made it possible to carry out a comprehensive interdisciplinary analysis of the evolution of spore morphology characters of the subfamily Pteridoideae, as well as to assess the relationships in the family Pteridaceae. The equatorial ridge (cingulum, "flange") has been proven as one of the key spore morphology features, which confirms the close relationship of "Onychium clade" with Pteris. The species-specific characters of the subfamily are fold and tubercle along laesura, equatorial ridge on proximal and distal side, tubercle, and folds on proximal and distal side. The knowledge will help to solve the problems of taxonomy in the family Preridaceae and to supplement the information on the natural classification of the subfamily Pteridoideae.


Assuntos
Gleiquênias , Pteridaceae , Traqueófitas , Humanos , Filogenia , Esporos
5.
Microsc Res Tech ; 85(2): 533-537, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34558769

RESUMO

In this article, we explored systematically the spore morphology of Pteridaceae by observation of the species distributed in Shandong Province using scanning electron microscopy (SEM). The results showed that the spore morphology of all the species in the family is tetrahedral and trilete. The characters of spore ornamentation are intraspecies stable, but significantly different among species and genera. Spore morphology is significant in exploring the phylogenetic relationships of Pteridaceae as well as in generic and specific delimitations.


Assuntos
Pteridaceae , China , Microscopia Eletrônica de Varredura , Filogenia , Esporos
6.
Methods Mol Biol ; 2368: 43-51, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34647246

RESUMO

Tropisms are among the most important growth responses for plant adaptation to the surrounding environment. One of the most common tropisms is root gravitropism. Root gravitropism enables the plant to anchor securely to the soil enabling the absorption of water and nutrients. Most of the knowledge related to the plant gravitropism has been acquired from the flowering plants, due to limited research in non-seed plants. Limited research on non-seed plants is due in large part to the lack of standard research methods. Here, we describe the experimental methods to evaluate gravitropism in representative non-seed plant species, including the non-vascular plant moss Physcomitrium patens, the early diverging extant vascular plant lycophyte Selaginella moellendorffii and fern Ceratopteris richardii. In addition, we introduce the methods used for statistical analysis of the root gravitropism in non-seed plant species.


Assuntos
Gravitropismo , Bryopsida , Plantas , Pteridaceae
7.
Methods Mol Biol ; 2368: 53-60, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34647247

RESUMO

Early studies revealed a highly predictable pattern of gravity-directed growth and development in Ceratopteris richardii spores. This makes the spore a valuable model system for the study of how a single-cell senses and responds to the force of gravity. Gravity regulates both the direction and magnitude of a trans-cell calcium current in germinating spores, and the orientation of this current predicts the polarization of spore development. In order to make Ceratopteris richardii cells easier to transform and image during this developmental process, a procedure for isolating protoplasts from Ceratopteris richardii gametophytes has been developed and optimized. These protoplasts follow the same developmental pattern as Ceratopteris richardii spores and can be used to monitor the molecular and developmental processes during single-cell polarization. Here, we describe this optimized procedure, along with protocols for sterilizing the spores, sowing them in solid or liquid growth media, and evaluating germination and polarization.


Assuntos
Sensação Gravitacional , Pteridaceae , Polaridade Celular , Protoplastos , Esporos
8.
Microsc Res Tech ; 84(12): 2867-2882, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34121271

RESUMO

Taxonomy and spore morphology of 12 taxa of Cheilanthoideae and Pteridoideae (Pteridaceae, Polypodiales) from Pakistan is illustrated with scanning electron microscopy images based upon the specimens collected from various localities. A total of six genera belong to 12 taxa viz. Actiniopteris radiata, Aleuritopteris albomarginata, A. ancepes, Notholaena himalaica, Oeosporangium nitidulum, O. pteridioides subsp. acrosticum, Onychium cryptogrammoides subsp. cryptogrammoides, O. vermae, Pteris cretica subsp. cretica, P. cretica subsp. laeta, P. vittata subsp. emodi, and P. vittata subsp. vittata were reported. Spore morphology of the taxa was trilete, triangular in proximal and distal view, ellipsoidal and hemicircular in equatorial view, polar proximal and distal surface with cristate, granulose, reticulate, perforate and tuberculate ornamentation.


Assuntos
Pteridaceae , Microscopia Eletrônica de Varredura , Paquistão , Esporos
9.
Plant Signal Behav ; 16(10): 1940001, 2021 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-34152254

RESUMO

Shoot meristems contain stem cells, and they sustain growth and development of the above-ground tissues in land plants. The HAIRY MERISTEM (HAM) family genes, encoding GRAS-domain transcriptional regulators, play essential roles in the control of shoot meristem development and stem cell homeostasis in several flowering plants. Similar to other GRAS proteins, the C-terminal regions of HAM family proteins across land plants are conserved, containing signature motifs that define the GRAS domain. In contrast, the N-terminal regions of HAM family proteins display substantial divergence in sequence and length. Whether the variable and divergent N-termini are required for the conserved functions of HAM proteins is unknown. Our recent work showed that CrHAM - the HAM homolog in the fern Ceratopteris richardii was able to replace the role of type-II HAM genes in Arabidopsis, maintaining established shoot apical meristems and promoting the initiation of new stem cell niches. Here, we provide additional information and show that CrHAM contains a much longer N-terminal region compared to Arabidopsis HAM proteins, which is conserved among different fern HAM homologs. The deletion of this region largely compromises the ability of CrHAM to replace the function of Arabidopsis HAM proteins in shoot meristems. These new data together with previous results suggest that, although lacking the sequence conservation among HAM homologs from different plant lineages, the N-termini are important for the conserved functions of HAM family proteins.


Assuntos
Arabidopsis/fisiologia , Genes de Plantas , Proteínas de Plantas/química , Pteridaceae/fisiologia , Fatores de Transcrição/química , Arabidopsis/química , Arabidopsis/genética , Família Multigênica , Proteínas de Plantas/genética , Plantas , Pteridaceae/química , Pteridaceae/genética , Fatores de Transcrição/genética
10.
J Exp Bot ; 72(20): 6990-7001, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34181730

RESUMO

The alternation of generations in land plants occurs between the sporophyte phase and the gametophyte phase. The sporophytes of seed plants develop self-maintained, multicellular meristems, and these meristems determine plant architecture. The gametophytes of seed plants lack meristems and are heterotrophic. In contrast, the gametophytes of seed-free vascular plants, including ferns, are autotrophic and free-living, developing meristems to sustain their independent growth and proliferation. Compared with meristems in the sporophytes of seed plants, the cellular mechanisms underlying meristem development in fern gametophytes remain largely unknown. Here, using confocal time-lapse live imaging and computational segmentation and quantification, we determined different patterns of cell divisions associated with the initiation and proliferation of two distinct types of meristems in gametophytes of two closely related Pteridaceae ferns, Pteris vittata and Ceratopteris richardii. Our results reveal how the simple timing of a switch between two meristems has considerable consequences for the divergent gametophyte morphologies of the two ferns. They further provide evolutionary insight into the function and regulation of gametophyte meristems in seed-free vascular plants.


Assuntos
Gleiquênias , Pteridaceae , Evolução Biológica , Células Germinativas Vegetais , Meristema
11.
Plant Physiol Biochem ; 164: 147-159, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33991860

RESUMO

The terrestrial fern Pityrogramma calomelanos, a cosmopolitan tropical species, is one of the strongest known arsenic (As) hyperaccumulator plants. This study aimed to determine whether P. calomelanos preferentially forages for arsenite (As3+) or arsenate (As5+) in As-contaminated soils, and whether a positive root response to As enhances accumulation in P. calomelanos. Therefore, an experiment using rhizoboxes divided in two halves were constructed with a control soil (C) and As3+ or As5+ dosed soil at either 50 and 100 µg g-1 As. Micro-X-ray Fluorescence elemental mapping (µXRF) was employed to analyze the distribution of As in roots and fronds, and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) was used to determine As distribution in the reproductive tissues of P. calomelanos. The results showed that Pityrogramma roots do not specifically forage for As-contaminated soil; the area based on pixel counts was similar across all the treatments with no statistical differences. However, frond biomass was slightly higher in the treatments C ǀ As3+ and C ǀ As5+, and the highest accumulation of As in fronds was in the As5+ ǀ As3+ (100 µg g-1) treatment, with 3418 and 2370 µg g-1 in old and young fronds respectively. Arsenic cycling across the roots was observed by the µXRF mapping; in C ǀ As5+ (100) the As was higher and evenly distributed in both sections, whilst in C ǀ As3+ (50), the As was higher in the As3+ side. The µXRF mapping showed a broader As distribution in older fronds, where As was highest in the rachis and extended into the pinnule through the midrib. Pityrogramma calomelanos does not specifically root forage for As-enriched zones in the soil and grows healthily without signs of toxicity at lower (50 µg g-1) and higher (100 µg g-1) concentrations of As3+ and As5+ in the soil.


Assuntos
Arsênio , Gleiquênias , Pteridaceae , Poluentes do Solo , Arsênio/análise , Biodegradação Ambiental , Raízes de Plantas/química , Solo , Poluentes do Solo/análise
12.
Microsc Res Tech ; 84(11): 2727-2736, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34051004

RESUMO

Taxonomy and spore morphology of genus Adiantum (Vittarioideae; Pteridaceae) from Pakistan is illustrated with scanning electron microscopy images based upon the specimens examined in herbaria of Pakistan, United Kingdom, and United States. A total of five species viz. Adiantum capillus-veneris, A. incisum subsp. incisum, A. pedatum subsp. pedatum, A. tibeticum, and A. venustum were reported with the habitat ecology of the species from Pakistan. Spore morphology of the taxa was trilete, triangular in proximal and distal view, ellipsoidal and hemicircular in equatorial view, polar proximal and distal surface was with tuberculate and granulose ornamentation.


Assuntos
Adiantum , Pteridaceae , Microscopia Eletrônica de Varredura , Paquistão , Esporos
13.
Genome Biol Evol ; 13(3)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33681974

RESUMO

As the closest extant sister group to seed plants, ferns are an important reference point to study the origin and evolution of plant genes and traits. One bottleneck to the use of ferns in phylogenetic and genetic studies is the fact that genome-level sequence information of this group is limited, due to the extreme genome sizes of most ferns. Ceratopteris richardii (hereafter Ceratopteris) has been widely used as a model system for ferns. In this study, we generated a transcriptome of Ceratopteris, through the de novo assembly of the RNA-seq data from 17 sequencing libraries that are derived from two sexual types of gametophytes and five different sporophyte tissues. The Ceratopteris transcriptome, together with 38 genomes and transcriptomes from other species across the Viridiplantae, were used to uncover the evolutionary dynamics of orthogroups (predicted gene families using OrthoFinder) within the euphyllophytes and identify proteins associated with the major shifts in plant morphology and physiology that occurred in the last common ancestors of euphyllophytes, ferns, and seed plants. Furthermore, this resource was used to identify and classify the GRAS domain transcriptional regulators of many developmental processes in plants. Through the phylogenetic analysis within each of the 15 GRAS orthogroups, we uncovered which GRAS family members are conserved or have diversified in ferns and seed plants. Taken together, the transcriptome database and analyses reported here provide an important platform for exploring the evolution of gene families in land plants and for studying gene function in seed-free vascular plants.


Assuntos
Embriófitas/genética , Embriófitas/metabolismo , Pteridaceae/genética , Pteridaceae/metabolismo , Transcriptoma , Evolução Molecular , Gleiquênias/classificação , Gleiquênias/genética , Genes de Plantas , Células Germinativas Vegetais , Filogenia , Domínios Proteicos , Pteridaceae/classificação
14.
Am J Bot ; 108(2): 263-283, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33624306

RESUMO

PREMISE: Xeric environments impose major constraints on the fern life cycle, yet many lineages overcome these limitations by evolving apomixis. Here, we synthesize studies of apomixis in ferns and present an evidence-based model for the evolution and establishment of this reproductive strategy, focusing on genetic and environmental factors associated with its two defining traits: the production of "unreduced" spores (n = 2n) and the initiation of sporophytes from gametophyte tissue (i.e., diplospory and apogamy, respectively). METHODS: We evaluated existing literature in light of the hypothesis that abiotic characteristics of desert environments (e.g., extreme diurnal temperature fluctuations, high light intensity, and water limitation) drive the evolution of obligate apomixis. Pellaeid ferns (Cheilanthoideae: Pteridaceae) were examined in detail, as an illustrative example. We reconstructed a plastid (rbcL, trnG-trnR, atpA) phylogeny for the clade and mapped reproductive mode (sexual versus apomictic) and ploidy across the resulting tree. RESULTS: Our six-stage model for the evolution of obligate apomixis in ferns emphasizes the role played by drought and associated abiotic conditions in the establishment of this reproductive approach. Furthermore, our updated phylogeny of pellaeid ferns reveals repeated origins of obligate apomixis and shows an increase in the frequency of apomixis, and rarity of sexual reproduction, among taxa inhabiting increasingly dry North American deserts. CONCLUSIONS: Our findings reinforce aspects of other evolutionary, physiological, developmental, and omics-based studies, indicating a strong association between abiotic factors and the establishment of obligate apomixis in ferns. Water limitation, in particular, appears critical to establishment of this reproductive mode.


Assuntos
Apomixia , Gleiquênias , Pteridaceae , Apomixia/genética , Secas , Gleiquênias/genética , Células Germinativas Vegetais
15.
Genes (Basel) ; 11(12)2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33291610

RESUMO

Ferns are a representative clade in plant evolution although underestimated in the genomic era. Ceratopteris richardii is an emergent model for developmental processes in ferns, yet a complete scheme of the different growth stages is necessary. Here, we present a developmental analysis, at the tissue and cellular levels, of the first shoot-borne root of Ceratopteris. We followed early stages and emergence of the root meristem in sporelings. While assessing root growth, the first shoot-borne root ceases its elongation between the emergence of the fifth and sixth roots, suggesting Ceratopteris roots follow a determinate developmental program. We report cell division frequencies in the stem cell niche after detecting labeled nuclei in the root apical cell (RAC) and derivatives after 8 h of exposure. These results demonstrate the RAC has a continuous mitotic activity during root development. Detection of cell cycle activity in the RAC at early times suggests this cell acts as a non-quiescent organizing center. Overall, our results provide a framework to study root function and development in ferns and to better understand the evolutionary history of this organ.


Assuntos
Ciclo Celular , Meristema/metabolismo , Pteridaceae/metabolismo , Meristema/citologia , Pteridaceae/citologia
16.
Mol Phylogenet Evol ; 152: 106938, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32791300

RESUMO

Cryptic species are present throughout the tree of life. They are especially prevalent in ferns, because of processes such hybridization, polyploidy, and reticulate evolution. In addition, the simple morphology of ferns limits phenotypic variation and makes it difficult to detect cryptic species. The model fern genus Ceratopteris has long been suspected to harbor cryptic diversity, in particular within the highly polymorphic C. thalictroides. Yet no studies have included samples from throughout its pan-tropical range or utilized genomic sequencing, making it difficult to assess the full extent of cryptic variation within this genus. Here, we present the first multilocus phylogeny of the genus using reduced representation genomic sequencing (RADseq) and examine population structure, phylogenetic relationships, and ploidy level variation. We recover similar species relationships found in previous studies, find support for the cryptic species C. gaudichaudii as genetically distinct, and identify novel genomic variation within two of the mostly broadly distributed species in the genus, C. thalictroides and C. cornuta. Finally, we detail the utility of our approach for working on cryptic, reticulate groups of ferns. Specifically, it does not require a reference genome, of which there are very few available for ferns. RADseq is a cost-effective way to work with study groups lacking genomic resources, and to obtain the thousands of nuclear markers needed to untangle species complexes.


Assuntos
Genoma de Planta/genética , Filogenia , Pteridaceae/classificação , Pteridaceae/genética , Sequência de Bases , Mapeamento Cromossômico , Genômica , Hibridização Genética , Poliploidia , Especificidade da Espécie
17.
Ecotoxicol Environ Saf ; 197: 110599, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32304919

RESUMO

Hydroponic experiment was conducted to investigate the biochemical responses and accumulation behaviour of cadmium (Cd) in aquatic fern, Ceratopteris pteridoides, under four different levels of exposure. Plants were grown in 10 µM (CdT1), 20 µM (CdT2), 40 µM (CdT3) and 60 µM (CdT4) concentrations of Cd for 12 consecutive days and Cd accumulation in different plant parts, cell levels and growth medium was estimated. In C. pteridoides, Cd removal kinetics was best described by pseudo-second-order kinetic model. Increased accumulation of Cd in the plants was detected in a concentration dependent manner with maximum under 60 µM of Cd (CdT4) exposure (191.38 mg kg-1, 186.19 mg kg-1 and 1316.34 mg kg-1 in leaves, stems and roots, respectively). Cell wall of C. pteridoides is identified as crucial Cd storage site with the highest (28-69%) accumulation followed by organelles (14-44%) and soluble fraction (6-46%). Increased leaf proline, malondialdehyde (MDA) and protein content with significant reduction (P < 0.05) in chlorophyll concentration and upregulation of antioxidant enzymes catalase (CAT), guaiacol peroxidase (POD) and superoxide dismutase (SOD) reveals the presence of Cd resistance mechanism in C. pteridoides. Calculated higher (>1) bioconcentration factor (BCF) and lower (<1) translocation factor (TF) values evinced the suitability of C. pteridoides in Cd phytostabilization rather than phytoextraction.


Assuntos
Cádmio/farmacocinética , Pteridaceae/metabolismo , Antioxidantes/metabolismo , Transporte Biológico , Cádmio/toxicidade , Catalase/metabolismo , Parede Celular/metabolismo , Clorofila/metabolismo , Hidroponia , Malondialdeído/metabolismo , Peroxidase/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Pteridaceae/efeitos dos fármacos , Pteridaceae/enzimologia , Superóxido Dismutase/metabolismo
18.
Am J Bot ; 107(4): 658-675, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32253761

RESUMO

PREMISE: Not all ferns grow in moist and shaded habitats. One well-known example is Notholaena standleyi, a species that thrives in deserts of the southwestern United States and Mexico. This species exhibits several "chemotypes" that differ in farina (flavonoid exudates) color and chemistry. By integrating data from molecular phylogenetics, cytology, biochemistry, and biogeography, we circumscribed the major evolutionary lineages within N. standleyi and reconstructed their diversification histories. METHODS: Forty-eight samples were selected from across the geographic distribution of N. standleyi. Phylogenetic relationships were inferred using four plastid and five nuclear markers. Ploidy levels were inferred using spore sizes calibrated by chromosome counts, and farina chemistry was compared using thin-layer chromatography. RESULTS: Four clades are recognized, three of which roughly correspond to previously recognized chemotypes. The diploid clades G and Y are found in the Sonoran and Chihuahuan deserts, respectively; they are estimated to have diverged in the Pleistocene, congruent with the postulated timing of climatological events separating these two deserts. Clade P/YG is tetraploid and partially overlaps the distribution of clade Y in the eastern Chihuahuan Desert. It is apparently confined to limestone, a geologic substrate rarely occupied by members of the other clades. The cryptic (C) clade, a diploid group known only from southern Mexico and highly disjunct from the other three clades, is newly recognized here. CONCLUSIONS: Our results reveal a complex intraspecific diversification history of N. standleyi, traceable to a variety of evolutionary drivers including classic allopatry, parapatry with or without changes in geologic substrate, and sympatric divergence through polyploidization.


Assuntos
Gleiquênias , Pteridaceae , México , Filogenia , Sudoeste dos Estados Unidos , Estados Unidos
19.
Bioorg Chem ; 98: 103756, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32200331

RESUMO

Aleuritopteris argentea (S. G. Gmél.) Fée is a medicinal fern consisting of an ent-labdane diterpene, i.e. alepterolic aicd, as the major metabolite. We recently isolated grams of alepterolic acid from A. argentea enabling subsequent structural modification. By incorporation of amino moiety to alepterolic acid, fifteen amide derivatives were synthesized, characterized, and further biological evaluated regarding their activity against four cancer cells and normal human liver cells. The potency of synthesized amides dramatically improved as compared to alepterolic aicd itself. The best hit (compound 11) inhibits HeLa cells with an IC50 of 7.39 ± 0.80 µM, and is nearly nontoxic to normal cells. Compound 11 exhibits an inhibitory effect on the colony forming ability of the four cancer cells, especially of HeLa cells. Moreover, it induces apoptosis of HeLa cells by decreasing mitochondrial membrane potential and altering expression of apoptosis-associated proteins. Release of cytochrome c, activation of caspases-3, caspases-9 and alteration of Bax/Bcl-2 balance was detected in the biological assays. These results imply that compound 11 can inhibit the proliferation of cervical cancer cell line HeLa and induce apoptosis through the mitochondrial pathway. These findings encourage further rational structural modification of 15- carboxyl group of alepterolic acid.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Pteridaceae/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diterpenos/química , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
20.
Mol Biol Evol ; 37(5): 1387-1393, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504735

RESUMO

The root originated independently in euphyllophytes (ferns and seed plants) and lycophytes; however, the molecular evolutionary route of root initiation remains elusive. By analyses of the fern Ceratopteris richardii and seed plants, here we show that the molecular pathway involving auxin, intermediate-clade WUSCHEL-RELATED HOMEOBOX (IC-WOX) genes, and WUSCHEL-clade WOX (WC-WOX) genes could be conserved in root initiation. We propose that the "auxin>IC-WOX>WC-WOX" module in root initiation might have arisen in the common ancestor of euphyllophytes during the second origin of roots, and that this module has further developed during the evolution of different root types in ferns and seed plants.


Assuntos
Evolução Molecular , Genes Homeobox , Ácidos Indolacéticos , Raízes de Plantas/crescimento & desenvolvimento , Pteridaceae/genética , Pteridaceae/crescimento & desenvolvimento
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