RESUMEN
(1) Background: In China and South Asia, Alstonia scholaris (Apocynaceae) is an important medicinal plant that has been historically used in traditional ethnopharmacy to treat infectious diseases. Although various pharmacological activities have been reported, the anti-lung cancer components of A. scholaris have not yet been identified. The objective of this study is to evaluate the active components of the leaf extract of A. scholaris, and assess the anti-proliferation effects of isolated compounds against non-small-cell lung carcinoma cells; (2) Methods: NMR was used to identify the chemical constitutes isolated from the leaf extract of A. scholaris. The anti-proliferative activity of compounds against non-small-cell lung carcinoma cells was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; (3) Results: Eight triterpenoids and five sterols were isolated from the hexane portion of A. scholaris, and structurally identified as: (1) ursolic acid, (2) oleanolic acid, (3) betulinic acid, (4) betulin, (5) 2ß,3ß,28-lup-20(29)-ene-triol, (6) lupeol, (7) ß-amyrin, (8) α-amyrin, (9) poriferasterol, (10) epicampesterol, (11) ß-sitosterol, (12) 6ß-hydroxy-4-stigmasten-3-one, and (13) ergosta-7,22-diene-3ß,5α,6ß-triol. Compound 5 was isolated from a plant source for the first time. In addition, compounds 9, 10, 12, and 13 were also isolated from A. scholaris for the first time. Ursolic acid, betulinic acid, betulin, and 2ß,3ß,28-lup-20(29)-ene-triol showed anti-proliferative activity against NSCLC, with IC50 of 39.8, 40.1, 240.5 and 172.6 µM, respectively.; (4) Conclusion: These findings reflect that pentacyclic triterpenoids are the anti-lung cancer chemicals in A. scholaris. The ability of ursolic acid, betulinic acid, betulin, and 2ß,3ß,28-lup-20(29)-ene-triol to inhibit the proliferative activity of NSCLC can constitute a valuable group of therapeutic agents in the future.
Asunto(s)
Alstonia/química , Antineoplásicos/farmacología , Fitosteroles/farmacología , Esteroles/farmacología , Triterpenos/farmacología , Células A549 , Antineoplásicos/química , Carcinoma de Pulmón de Células no Pequeñas , Proliferación Celular/efectos de los fármacos , Humanos , Neoplasias Pulmonares , Triterpenos Pentacíclicos , Fitosteroles/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Esteroles/química , Sales de Tetrazolio/química , Tiazoles/química , Triterpenos/química , Ácido Betulínico , Ácido UrsólicoRESUMEN
BACKGROUND: Gastrodia elata Blume (Orchidaceae) is an important Chinese medicine with several functional components. In the life cycle of G. elata, the orchid develops a symbiotic relationship with two compatible mycorrhizal fungi Mycena spp. and Armillaria mellea during seed germination to form vegetative propagation corm and vegetative growth to develop tubers, respectively. Gastrodin (p-hydroxymethylphenol-beta-D-glucoside) is the most important functional component in G. elata, and gastrodin significantly increases from vegetative propagation corms to tubers. To address the gene regulation mechanism in gastrodin biosynthesis in G. elata, a comparative analysis of de novo transcriptome sequencing among the vegetative propagation corms and tubers of G. elata and A. mellea was conducted using deep sequencing. RESULTS: Transcriptome comparison between the vegetative propagation corms and juvenile tubers of G. elata revealed 703 differentially expressed unigenes, of which 298 and 405 unigenes were, respectively up-regulated (fold-change ≥ 2, q-value < 0.05, the trimmed mean of M-values (TMM)-normalized fragments per kilobase of transcript per Million mapped reads (FPKM) > 10) and down-regulated (fold-change ≤ 0.5, q-value <0.05, TMM-normalized FPKM > 10) in juvenile tubers. After Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, 112 up-regulated unigenes with KEGG Ortholog identifiers (KOids) or enzyme commission (EC) numbers were assigned to 159 isogroups involved in seventy-eight different pathways, and 132 down-regulated unigenes with KOids or EC numbers were assigned to 168 isogroups, involved in eighty different pathways. The analysis of the isogroup genes from all pathways revealed that the two unigenes TRINITY_DN54282_c0_g1 (putative monooxygenases) and TRINITY_DN50323_c0_g1 (putative glycosyltransferases) might participate in hydroxylation and glucosylation in the gastrodin biosynthetic pathway. CONCLUSIONS: The gene expression of the two unique unigenes encoding monooxygenase and glycosyltransferase significantly increases from vegetative propagation corms to tubers, and the molecular basis of gastrodin biosynthesis in the tubers of G. elata is proposed.
Asunto(s)
Gastrodia/genética , Glucósidos/biosíntesis , Simbiosis/genética , Transcriptoma , Agaricales , Alcoholes Bencílicos , Gastrodia/microbiología , Regulación de la Expresión Génica de las Plantas , Ontología de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Micorrizas , Tubérculos de la Planta/genética , Tubérculos de la Planta/microbiología , ARN de Planta/genética , Análisis de Secuencia de ARNRESUMEN
(1) BACKGROUND: Several triterpenoids were found to act synergistically with classes of antibiotic, indicating that plant-derived chemicals have potential to be used as therapeutics to enhance the activity of antibiotics against multidrug-resistant pathogens. However, the mode of action of triterpenoids against bacterial pathogens remains unclear. The objective of this study is to evaluate the interaction between ursolic acid against methicillin-resistant Staphylococcus aureus (MRSA); (2) METHODS: The ability of ursolic acid to damage mammalian and bacterial membranes was examined. The proteomic response of methicillin-resistant S. aureus in ursolic acid treatment was investigated using two-dimensional (2D) proteomic analysis; (3) RESULTS: Ursolic acid caused the loss of staphylococcal membrane integrity without hemolytic activity. The comparison of the protein pattern of ursolic acid-treated and normal MRSA cells revealed that ursolic acid affected a variety of proteins involved in the translation process with translational accuracy, ribonuclease and chaperon subunits, glycolysis and oxidative responses; (4) CONCLUSION: The mode of action of ursolic acid appears to be the influence on the integrity of the bacterial membrane initially, followed by inhibition of protein synthesis and the metabolic pathway. These findings reflect that the pleiotropic effects of ursolic acid against MRSA make it a promising antibacterial agent in pharmaceutical research.
Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Triterpenos/química , Triterpenos/farmacología , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Membrana Celular/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/fisiología , Pruebas de Sensibilidad Microbiana , Modelos Biológicos , Estructura Molecular , Biosíntesis de Proteínas/efectos de los fármacos , Mapeo de Interacción de Proteínas , Mapas de Interacción de Proteínas , Proteómica/métodos , Ovinos , Ácido UrsólicoRESUMEN
(1) BACKGROUND: Alstonia scholaris (Apocynaceae) is an important medicinal plant that has been historically used in "Dai" ethnopharmacy to treat infectious diseases in China. Although various pharmacological activities have been reported, the antimicrobial constitutes of A. scholaris have not yet been identified. The objective of this study is to evaluate the antibacterial constitutes from the leaf extract of A. scholaris and to assess the synergistic effects of isolated compounds with antibiotics against bacterial pathogens.; (2) METHODS: The chemical constitutes isolated from the leaf extract of A. scholaris were structurally identified by NMR. The antibacterial and synergistic effect of compounds was assessed by calculating the minimal inhibitory concentration (MIC), checkerboard dilution test, and time-kill assay.; (3) RESULTS: Six pentacyclic triterpenoids were structurally identified as (1) lupeol, (2) betulin, (3) 3-hydroxy-11-ursen-28,13-olide, (4) betulinic acid, (5) oleanolic acid and (6) ursolic acid. Both oleanolic and ursolic acid showed antibacterial activity but were limited to Gram-positive bacteria. Ursolic acid showed a synergistic effect with ampicillin and tetracycline against both Bacillus cereus and S. aureus.; (4) CONCLUSION: These findings reflect that pentacyclic triterpenoids are the antibacterial chemicals in A. scholaris. The ability of ursolic acid to enhance the activity of antibiotics can constitute a valuable group of therapeutic agents in the future.
Asunto(s)
Alstonia/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Triterpenos Pentacíclicos/aislamiento & purificación , Triterpenos Pentacíclicos/farmacología , Ampicilina/farmacología , Bacillus cereus/efectos de los fármacos , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Staphylococcus aureus/efectos de los fármacos , Tetraciclina/farmacologíaRESUMEN
Young incipient species provide ideal materials for untangling the process of ecological speciation in the presence of gene flow. The Miscanthus floridulus/sinensis complex exhibits diverse phenotypic and ecological differences despite recent divergence (approximately 1.59 million years ago). To elucidate the process of genetic differentiation during early stages of ecological speciation, we analyzed genomic divergence in the Miscanthus complex using 72 randomly selected genes from a newly assembled transcriptome. In this study, rampant gene flow was detected between species, estimated as M = 3.36 × 10(-9) to 1.20 × 10(-6) , resulting in contradicting phylogenies across loci. Nevertheless, beast analyses revealed the species identity and the effects of extrinsic cohesive forces that counteracted the non-stop introgression. As expected, early in speciation with gene flow, only 3-13 loci were highly diverged; two to five outliers (approximately 2.78-6.94% of the genome) were characterized by strong linkage disequilibrium, and asymmetrically distributed among ecotypes, indicating footprints of diversifying selection. In conclusion, ecological speciation of incipient species of Miscanthus probably followed the parapatric model, whereas allopatric speciation cannot be completely ruled out, especially between the geographically isolated northern and southern M. sinensis, for which no significant gene flow across oceanic barriers was detected. Divergence between local ecotypes in early-stage speciation began at a few genomic regions under the influence of natural selection and divergence hitchhiking that overcame gene flow.
Asunto(s)
Flujo Génico , Filogenia , Poaceae/genética , China , Ecotipo , Especiación Genética , Variación Genética , Genética de Población , Desequilibrio de Ligamiento , Modelos Genéticos , TaiwánRESUMEN
BACKGROUND: Phalaenopsis is one of the important commercial orchids in the world. Members of the P. amabilis species complex represent invaluable germplasm for the breeding program. However, the phylogeny of the P. amabilis species complex is still uncertain. The Phalaenopsis amabilis species complex (Orchidaceae) consists of subspecies amabilis, moluccana, and rosenstromii of P. amabilis, as well as P. aphrodite ssp. aphrodite, P. ap. ssp. formosana, and P. sanderiana. The aims of this study were to reconstruct the phylogeny and biogeographcial patterns of the species complex using Neighbor Joining (NJ), Maxinum Parsimony (MP), Bayesian Evolutionary Analysis Sampling Trees (BEAST) and Reconstruct Ancestral State in Phylogenies (RASP) analyses based on sequences of internal transcribed spacers 1 and 2 from the nuclear ribosomal DNA and the trnH-psbA spacer from the plastid DNA. RESULTS: A pattern of vicariance, dispersal, and vicariance + dispersal among disjunctly distributed taxa was uncovered based on RASP analysis. Although two subspecies of P. aphrodite could not be differentiated from each other in dispersal state, they were distinct from P. amabilis and P. sanderiana. Within P. amabilis, three subspecies were separated phylogenetically, in agreement with the vicariance or vicariance + dispersal scenario, with geographic subdivision along Huxley's, Wallace's and Lydekker's Lines. Molecular dating revealed such subdivisions among taxa of P. amabilis complex dating back to the late Pleistocene. Population-dynamic analyses using a Bayesian skyline plot suggested that the species complex experienced an in situ range expansion and population concentration during the late Last Glacial Maximum (LGM). CONCLUSIONS: Taxa of the P. amabilis complex with disjunct distributions were differentiated due to vicariance or vicariance + dispersal, with events likely occurring in the late Pleistocene. Demographic growth associated with the climatic oscillations in the Würm glacial period followed the species splits. Nevertheless, a subsequent population slowdown occurred in the late LGM due to extinction of regional populations. The reduction of suitable habitats resulted in geographic fragmenttation of the remaining taxa.
Asunto(s)
ADN de Plantas/genética , ADN Ribosómico/genética , Flujo Génico , Orchidaceae/fisiología , Dispersión de las Plantas , Teorema de Bayes , Núcleo Celular/genética , Núcleo Celular/metabolismo , ADN de Cloroplastos/genética , ADN de Cloroplastos/metabolismo , ADN de Plantas/metabolismo , ADN Ribosómico/metabolismo , ADN Espaciador Ribosómico/genética , ADN Espaciador Ribosómico/metabolismo , Datos de Secuencia Molecular , Orchidaceae/citología , Orchidaceae/genética , Filogenia , Filogeografía , Análisis de Secuencia de ADNRESUMEN
Rhododendron formosanum is an endemic species distributed in the central mountains of Taiwan. In this study, the biological activities of major procyanidins isolated from the leaf extract of R. formosanum were investigated. Four compounds, including two procyanidin dimers, procyanidin A1 (1) and B3 (2), and two procyanidin trimmers, procyanidin C4 (4) and cinnamtannin D1 (5), were isolated and identified on the basis of spectroscopic data. The structure of a new procyanidin dimer, rhodonidin A (3), was elucidated by 2D-NMR, CD spectrum and MS. The procyanidin trimmers and rhodonidin A are reported for the first time in Ericaceae. The biological activities of these procyanidins were evaluated using anti-bacterial and anti-oxidative assays. Only the new compound 3 demonstrated strong anti-bacterial activity against Staphylococcus aureus at an MIC value of 4 µg/mL. All compounds showed pronounced antioxidant activities and the activities are enhanced as the amount of OH groups in procyanidins increased. In conclusion, the pleiotropic effects of procyanidins isolated from the leaves of R. formosanum can be a source of promising compounds for the development of future pharmacological applications.
Asunto(s)
Antibacterianos/química , Antioxidantes/química , Hojas de la Planta/química , Proantocianidinas/química , Rhododendron/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/química , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Oxidación-Reducción , Picratos/antagonistas & inhibidores , Picratos/química , Extractos Vegetales/química , Proantocianidinas/aislamiento & purificación , Proantocianidinas/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Relación Estructura-Actividad , TaiwánRESUMEN
Alstonia scholaris is a tropical evergreen tree native to South and Southeast Asia. Alstonia forests frequently lack understory species. However, potential mechanisms-particularly the allelochemicals involved-remain unclear. In the present study, we identified allelochemicals of A. scholaris, and clarified the role of allelopathic substances from A. scholaris in interactions with neighboring plants. We showed that the leaves, litter, and soil from A. scholaris inhibited growth of Bidens pilosa-a weed found growing abundantly near A. scholaris forests. The allelochemicals were identified as pentacyclic triterpenoids, including betulinic acid, oleanolic acid, and ursolic acid by using (1)H and (13)C-NMR spectroscopy. The half-maximal inhibitory concentration (IC50) for radicle growth of B. pilosa and Lactuca sativa ranged from 78.8 µM to 735.2 µM, and ursolic acid inhibited seed germination of B. pilosa. The triterpenoid concentrations in the leaves, litter, and soil were quantified with liquid chromatography-electrospray ionization/tandem mass spectrometry. Ursolic acid was present in forest soil at a concentration of 3,095 µg/g, i.e., exceeding the IC50. In the field, ursolic acid accumulated abundantly in the soil in A. scholaris forests, and suppressed weed growth during summer and winter. Our results indicate that A. scholaris pentacyclic triterpenoids influence the growth of neighboring weeds by inhibiting seed germination, radicle growth, and functioning of photosystem II.
Asunto(s)
Alelopatía , Alstonia/metabolismo , Feromonas/química , Feromonas/farmacología , Triterpenos/química , Triterpenos/farmacología , Bidens/efectos de los fármacos , Bidens/crecimiento & desarrollo , Bidens/metabolismo , Germinación/efectos de los fármacos , Feromonas/análisis , Feromonas/metabolismo , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/metabolismo , Malezas/efectos de los fármacos , Malezas/crecimiento & desarrollo , Malezas/metabolismo , Suelo/química , Triterpenos/análisis , Triterpenos/metabolismo , Ácido UrsólicoRESUMEN
BACKGROUND: Autotoxicity plays an important role in regulating crop yield and quality. To help characterize the autotoxicity mechanism of rice, we performed a large-scale, transcriptomic analysis of the rice root response to ferulic acid, an autotoxin from rice straw. RESULTS: Root growth rate was decreased and reactive oxygen species, calcium content and lipoxygenase activity were increased with increasing ferulic acid concentration in roots. Transcriptome analysis revealed more transcripts responsive to short ferulic-acid exposure (1- and 3-h treatments, 1,204 genes) than long exposure (24 h, 176 genes). Induced genes were involved in cell wall formation, chemical detoxification, secondary metabolism, signal transduction, and abiotic stress response. Genes associated with signaling and biosynthesis for ethylene and jasmonic acid were upregulated with ferulic acid. Ferulic acid upregulated ATP-binding cassette and amino acid/auxin permease transporters as well as genes encoding signaling components such as leucine-rich repeat VIII and receptor-like cytoplasmic kinases VII protein kinases, APETALA2/ethylene response factor, WRKY, MYB and Zinc-finger protein expressed in inflorescence meristem transcription factors. CONCLUSIONS: The results of a transcriptome analysis suggest the molecular mechanisms of plants in response to FA, including toxicity, detoxicification and signaling machinery. FA may have a significant effect on inhibiting rice root elongation through modulating ET and JA hormone homeostasis. FA-induced gene expression of AAAP transporters may contribute to detoxicification of the autotoxin. Moreover, the WRKY and Myb TFs and LRR-VIII and SD-2b kinases might regulate downstream genes under FA stress but not general allelochemical stress. This comprehensive description of gene expression information could greatly facilitate our understanding of the mechanisms of autotoxicity in plants.
Asunto(s)
Ácidos Cumáricos/farmacología , Oryza/efectos de los fármacos , Oryza/genética , Raíces de Plantas/efectos de los fármacos , Transcriptoma , Calcio/metabolismo , Pared Celular/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Peroxidación de Lípido/efectos de los fármacos , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Anotación de Secuencia Molecular , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Reguladores del Crecimiento de las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Polisacáridos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Estrés FisiológicoRESUMEN
Three novel C19 homolignans, taiwankadsurins D (1), E (2) and F (4), and two new C18 lignans kadsuphilins N (3) and O (5) were isolated from the aerial parts of Taiwanese medicinal plant Kadsura philippinensis. The structures of compounds 1-5 were determined by spectroscopic analyses, especially 2D NMR techniques. The structure of compound 5 was further confirmed by X-ray crystallographic analysis. Compounds 1 and 2 have a 3,4-{1'-[(Z)-2''-methoxy-2''-oxoethylidene]}-pentano(2,3-dihydrobenzo[b]furano)-3-(2'''-methoxycarbonyl-2'''-hydroxy-2''',3'-epoxide) skeleton.
Asunto(s)
Kadsura/química , Lignanos/química , Hojas de la Planta/química , Tallos de la Planta/química , Lignanos/análisis , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Extractos Vegetales/análisis , Extractos Vegetales/químicaRESUMEN
Nine new derivatives of oleanane triterpenoids isolated from Fatsia polycarpa Hayata were synthesized through chemical transformations. Acetylation was effected by reaction with acetic anhydride in pyridine to afford compounds 1-5, while compound 6 was obtained using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl) in CH2Cl2. The others derivatives 7-9 were obtained in reactions of the corresponding triterpenoids with EDC·HCl, 4-N,N-dimethylaminopyridine hydrochloride and 4-N,N-dimethylaminopyridine in CH2Cl2. The structures of 1-9 were elucidated from extensive spectroscopic and HRESIMS data, while the structure of 9 was further confirmed by X-ray diffraction analysis. The cytotoxic, anti-hepatitis B virus (HBV), antibacterial, hypoglycaemic and Wnt signaling activities of these derivatives were evaluated in vitro.
Asunto(s)
Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacología , Antibacterianos/síntesis química , Antibacterianos/farmacología , Antivirales/síntesis química , Antivirales/farmacología , Araliaceae/química , Glucosa/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Células Hep G2 , Virus de la Hepatitis B/efectos de los fármacos , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/farmacología , Concentración 50 Inhibidora , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Conformación Molecular , Ácido Oleanólico/síntesis química , Vía de Señalización Wnt/efectos de los fármacosRESUMEN
Increasing evidence suggests that in disease-suppressive soils, microbial volatile compounds (mVCs) released from bacteria may inhibit the growth of plant-pathogenic fungi. However, the antifungal activities and molecular responses of fungi to different mVCs remain largely undescribed. In this study, we first evaluated the responses of pathogenic fungi to treatment with mVCs from Paenarthrobacter ureafaciens. Then, we utilized the well-characterized fungal model organism Saccharomyces cerevisiae to study the potential mechanistic effects of the mVCs. Our data showed that exposure to P. ureafaciens mVCs leads to reduced growth of several pathogenic fungi, and in yeast cells, mVC exposure prompts the accumulation of reactive oxygen species. Further experiments with S. cerevisiae deletion mutants indicated that Slt2/Mpk1 and Hog1 MAPKs play major roles in the yeast response to P. ureafaciens mVCs. Transcriptomic analysis revealed that exposure to mVCs was associated with 1,030 differentially expressed genes (DEGs) in yeast. According to gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses, many of these DEGs are involved in mitochondrial dysfunction, cell integrity, mitophagy, cellular metabolism, and iron uptake. Genes encoding antimicrobial proteins were also significantly altered in the yeast after exposure to mVCs. These findings suggest that oxidative damage and mitochondrial dysfunction are major contributors to the fungal toxicity of mVCs. Furthermore, our data showed that cell wall, antioxidant, and antimicrobial defenses are induced in yeast exposed to mVCs. Thus, our findings expand upon previous research by delineating the transcriptional responses of the fungal model. IMPORTANCE Since the use of bacteria-emitted volatile compounds in phytopathogen control is of considerable interest, it is important to understand the molecular mechanisms by which fungi may adapt to microbial volatile compounds (mVCs). Paenarthrobacter ureafaciens is an isolated bacterium from disease-suppressive soil that belongs to the Actinomycetota phylum. P. ureafaciens mVCs showed a potent antifungal effect on phytopathogens, which may contribute to disease suppression in soil. However, our knowledge about the antifungal mechanism of mVCs is limited. This study has proven that mVCs are toxic to fungi due to oxidative stress and mitochondrial dysfunction. To deal with mVC toxicity, antioxidants and physical defenses are required. Furthermore, iron uptake and CAP proteins are required for antimicrobial defense, which is necessary for fungi to deal with the thread from mVCs. This study provides essential foundational knowledge regarding the molecular responses of fungi to inhibitory mVCs.
Asunto(s)
Antiinfecciosos , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Antifúngicos/farmacología , Suelo , Hongos , Antiinfecciosos/farmacología , HierroRESUMEN
A prominent hypothesis in ecology is that larger species ranges are found in more variable climates because species develop broader environmental tolerances, predicting a positive range size-temperature variability relationship. However, this overlooks the extreme temperatures that variable climates impose on species, with upper or lower thermal limits more likely to be exceeded. Accordingly, we propose the 'temperature range squeeze' hypothesis, predicting a negative range size-temperature variability relationship. We test these contrasting predictions by relating 88,000 elevation range sizes of vascular plants in 44 mountains to short- and long-term temperature variation. Consistent with our hypothesis, we find that species' range size is negatively correlated with diurnal temperature range. Accurate predictions of short-term temperature variation will become increasingly important for extinction risk assessment in the future.
Asunto(s)
Clima , Ecosistema , Temperatura , Calor , Cambio ClimáticoRESUMEN
BACKGROUND AND AIMS: Investigating intraspecific karyotypic and genetic variations jointly can provide unique insights into how historical, ecological and cytogenetic factors influence microevolution. A coastal herb, Lysimachia mauritiana, exhibits extensive karyotypic polymorphism and displays a complex cytogeographic pattern across the Ryukyus. To explore whether a similar degree of chromosomal variation exists south of the Ryukyus, and in an attempt to ascertain the mechanisms that may have generated the patterns, comprehensive sampling was conducted in Taiwan. METHODS: Karyotypes were analysed at mitotic metaphase for 550 individuals from 42 populations throughout Taiwan Proper and its adjacent islands. In addition, genetic variation was estimated using 12 allozymes (21 loci) of 314 individuals sampled from 12 localities. KEY RESULTS: Four chromosome numbers and eight cytotypes, including four endemic cytotypes, were detected. Cytotype distributions were highly structured geographically, with single cytotypes present in most populations and four major cytotypes dominating the north, east and south of Taiwan and the Penghu Archipelago. Allozyme variation was very low and F-statistics indicated an extremely high level of population differentiation, implying limited gene flow among populations. Cluster analysis of allozyme variation uncovered four geographic groups, each corresponding perfectly to the four dominant cytotypes. The geographic structure of cytotype distribution and allozyme variation probably resulted from severe genetic drift triggered by genetic bottlenecks, suggesting that Taiwanese populations were likely to be derived from four independent founder events. In the few localities with multiple cytotypes, cytogeographic patterns and inferences of chromosomal evolution revealed a trend of northward dispersal, consistent with the course of the Kuroshio Current that has been influential in shaping the coastal biota of the region. CONCLUSIONS: The data elucidate the patterns of colonization and the effects of the Kuroshio Current on the distribution of L. mauritiana in Taiwan. These inferences are highly relevant to other coastal plant species in the region and will stimulate further studies.
Asunto(s)
Isoenzimas , Polimorfismo Genético/genética , Primulaceae/genética , Evolución Biológica , Cromosomas de las Plantas/genética , Sitios Genéticos/genética , Variación Genética , Genética de Población , Geografía , Cariotipo , Meiosis/genética , Mitosis/genética , Filogenia , Primulaceae/enzimología , TaiwánRESUMEN
PREMISE OF THE STUDY: Microsatellite loci were developed from Imperata cylindrica, a traditional medicinal herb in Asia and among the top 10 worst invasive weeds in the world, to aid in the identification of the limits of asexual clonal individuals. METHODS AND RESULTS: A total of 21 microsatellite markers, including 18 polymorphic and three monomorphic loci, were developed from I. cylindrica using a magnetic bead enrichment protocol. The primers amplified dinucleotide, trinucleotide, and complex repeats. The number of alleles ranged from one to 19 per locus, with an observed heterozygosity ranging from 0.09 to 1.00. Several loci deviated significantly from the within-population Hardy-Weinberg equilibrium as a result of asexual clonal reproduction. CONCLUSIONS: These polymorphic markers should be useful tools in further studies on the identification of the range of clonal reproduction units and the selection and classification of the medicinal cultivar.
Asunto(s)
Repeticiones de Microsatélite/genética , Malezas/genética , Plantas Medicinales/genética , Poaceae/genética , Secuencia de Bases , ADN de Plantas/química , ADN de Plantas/genética , Variación Genética , Genotipo , Geografía , Japón , Desequilibrio de Ligamiento , Datos de Secuencia Molecular , Polimorfismo Genético , Análisis de Secuencia de ADN , TaiwánRESUMEN
The landrace strains of Momordica charantia are widely cultivated vegetables throughout the tropics and subtropics, but not in Taiwan, a continental island in Southeast Asia, until a few hundred years ago. In contrast, the related wild populations with smaller fruit sizes are native to Taiwan. Because of the introduction of cultivars for agricultural purposes, these two accessions currently exhibit a sympatric or parapatric distribution in Taiwan. In this study, the cultivars and wild samples from Taiwan, India, and Korea were collected for testing of their hybridization and evolutionary patterns. The cpDNA marker showed a clear distinction between accessions of cultivars and wild populations of Taiwan and a long divergence time. In contrast, an analysis of eight selectively neutral nuclear microsatellite loci did not reveal a difference between the genetic structures of these two accessions. A relatively short divergence time and frequent but asymmetric gene flows were estimated based on the isolation-with-migration model. Historical and current introgression from cultivars to wild populations of Taiwan was also inferred using MIGRATE-n and BayesAss analyses. Our results showed that these two accessions shared abundant common ancestral polymorphisms, and the timing of the divergence and colonization of the Taiwanese wild populations is consistent with the geohistory of the Taiwan Strait land bridge of the Last Glacial Maximum (LGM). Long-term and recurrent introgression between accessions indicated the asymmetric capacity to receive foreign genes from other accessions. The modern introduction of cultivars of M. charantia during the colonization of Taiwan by the Han Chinese ethnic group enhanced the rate of gene replacement in the native populations and resulted in the loss of native genes.
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Cloroplastos/genética , ADN de Cloroplastos/análisis , Momordica charantia/clasificación , Momordica charantia/genética , Evolución Molecular , Hibridación Genética , India , Especies Introducidas , Repeticiones de Microsatélite , Momordica charantia/citología , Filogenia , Filogeografía , República de Corea , Especificidad de la Especie , TaiwánRESUMEN
Seven new oleanane-type triterpenoids (1-7), named fatsicarpains A-G, and the known compounds 3α-hydroxyolean-11,13(18)-dien-28-oic acid (8) and 3α-hydroxyolean-11-en-28,13ß-olide (9) were isolated from the leaves and twigs of Fatsia polycarpa on the basis of bioassay-guided fractionation. The structures of compounds 1-7 were elucidated through spectroscopic analyses and single-crystal X-ray crystallography of 1, 8, and 9. Cytotoxicity against HepG2 2.2.15 and AGS cells and antihepatitis B virus (HBV) and antibacterial activities of 1-9 were also evaluated in vitro.
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Antineoplásicos Fitogénicos/aislamiento & purificación , Araliaceae/química , Ácido Oleanólico/análogos & derivados , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Virus de la Hepatitis B/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Ácido Oleanólico/química , Ácido Oleanólico/aislamiento & purificación , Ácido Oleanólico/farmacología , Hojas de la Planta/química , Tallos de la Planta/químicaRESUMEN
OBJECTIVES: To identify the vulnerable regions with underlying susceptibility and poor adaptive capability in response to cold and heat events in Taiwan, and to characterise the determinants associated with such an increasing risk to design better adaptive strategies in view of predicted weather changes in the future. METHODS: The authors used spatial regression models to measure the relationships between the spatial characteristics of temperature, extracted factors from demographic and socio-economic parameters, and the mean cardiovascular mortality 2 weeks before and after cold or heat events from 1994 to 2003. RESULTS: Metropolitan regions were found to have a substantially lower mortality than rural areas after cold and heat events. Events of cold, compared with heat, had greater impacts on the mortality ratio in most townships. A negative association was identified, using a spatial lag model, between the mortality after cold and heat events and urbanisation, and the availability of medical resources. A higher percentage of older people, vulnerable and aborigines might have contributed to the increasing vulnerability of townships during cold and heat events. CONCLUSIONS: These data, using an island-wide spatial analysis, suggest that urban areas have a greater adaptive capability than rural areas, plausibly because people in urban areas have a higher socio-economic status and more medical resources. Social inequality across urban and rural townships is apparent and developing customised adaptation programmes for vulnerable regions to cope with heat and cold event should be prioritised.
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Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/mortalidad , Frío/efectos adversos , Calor/efectos adversos , Adolescente , Adulto , Factores de Edad , Anciano , Femenino , Sistemas de Información Geográfica , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Salud Rural/estadística & datos numéricos , Factores Socioeconómicos , Taiwán/epidemiología , Salud Urbana/estadística & datos numéricos , Adulto JovenRESUMEN
BACKGROUND: The present study used insurance claims data to investigate infections associated with short-term water outage because of constructions or pipe breaks. METHODS: The present study used medical claims of one million insured persons for 2004-2006. We estimated incidences of gastroenteritis and eye and skin complaints for 10 days before, during, and after 10 days of water supply restriction for outpatient visits and for emergency and in-patient care combined. RESULTS: There was an increase in medical services for these complaints in outpatient visits because of water outages. Poisson regression analyses showed that increased risks of medical services were significant for gastroenteritis (relative risk [RR] 1.31, 95% confidence interval [CI] 1.26-1.37), skin disease (RR 1.36, 95% CI 1.30-1.42), and eye disease patients (RR 1.34, 95% CI 1.26-1.44). Similar risks were observed during 10-day lag periods. Compared with those in cool days, risks of medical services are higher when average daily temperature is above 30 °C for gastroenteritis (RR 12.1, 95% CI 6.17-23.7), skin diseases (RR 4.48, 95% CI 2.29-8.78), and eye diseases (RR 40.3, 95% CI 7.23-224). CONCLUSION: We suggest promoting personal hygiene education during water supply shortages, particularly during the warm months.