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1.
Sci Rep ; 14(1): 6164, 2024 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486071

RESUMO

Stevia (Stevia rebaudiana Bertoni) is a natural sweetener plant that accumulates highly sweet steviol glycosides (SGs) especially in leaves. Stevia is native to humid areas and does not have a high tolerance to drought which is the most serious abiotic stress restricting its production worldwide. C2H2 zinc finger proteins (C2H2-ZFPs) are a group of well-known transcription factors that involves in various developmental, physiological and biochemical activities as well as in response to abiotic stresses. Here we analyzed C2H2-ZFP gene family in stevia and identified a total of 185 putative SrC2H2-ZF proteins from the genome sequence of S. rebaudiana. We further characterized the identified C2H2-ZF domains and their organization, additional domains and motifs and analyzed their physicochemical properties, localization and gene expression patterns. The cis-element analysis suggested multiple roles of SrC2H2-ZFPs in response to light, phytohormone, and abiotic stresses. In silico analysis revealed that the stevia C2H2-ZFP genes are interactively expressed in different tissues and developmental stages and some C2H2-ZFP genes are involved in response to drought stress. This study provides a background for future exploration of the functional, and regulatory aspects of the C2H2-ZFP gene family in S. rebaudiana.


Assuntos
Stevia , Stevia/genética , Folhas de Planta/genética , Estresse Fisiológico/genética
2.
Gene ; 893: 147911, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37863301

RESUMO

Sunn pest (Eurygaster integriceps Puton) is major wheat pest causing economic damage. Neuropeptides and their receptors, G protein-coupled receptors (GPCRs), are involved in the regulation of insect physiology and behavior. Herein, a transcriptome-wide analysis was conducted in order to identify genes encoding neuropeptides, and putative GPCRs to gain insight into neuropeptide-modulated processes. De novo transcriptome assembly was undertaken using paired-end sequence reads derived from RNA samples collected from whole adults and yielded 582,398 contigs. In total, 46 neuropeptides have been identified, encompassing various known insect neuropeptide families. In addition, we discovered four previously uncharacterized neuroparsin peptides, which contributes to our understanding of the neuropeptide landscape. Furthermore, 85 putative neuropeptide GPCRs were identified, comprising three classes of GPCRs, A, B, C, and LGR, of which class C is not widely reported in insects. In addition, the identified GPCRs exhibited a remarkable 80% homology with the GPCRs found in the brown marmorated stink bug. It is noteworthy that these GPCRs displayed only a 20% homology to GPCRs from many other insect species. This information may be used to understand the neuropeptide-modulated physiology and behavior of Eurygaster integriceps, and to develop specific neuropeptide-based pest management strategies.


Assuntos
Heterópteros , Neuropeptídeos , Humanos , Animais , Transcriptoma/genética , Heterópteros/genética , Neuropeptídeos/genética , Insetos/genética , Receptores Acoplados a Proteínas G/genética
3.
Phytochemistry ; 202: 113290, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35803303

RESUMO

Nigella sativa (Black cumin) has many applications in food and pharmaceutical industries. Thymoquinone has been considered as a main effective compound in N. sativa seeds and attracted researchers' attention mainly due to its medicinal potential. In this study, the essential oil components of leaves, flowers and seed developmental stages including half black seeds, soft black seeds and hard black seeds were analyzed in N. sativa. Whereas no terpenes were detected in flowers and leaves, seeds showed an essential oil composition that increased in its thymoquinone content during seed maturation. To study the proposed first step of thymoquinone biosynthesis, the formation of γ-terpinene from geranyl diphosphate (GDP), we identified and functionally characterized a γ-terpinene synthase (NsTPS1) in N. sativa. This monoterpene synthase was identified in RNA sequence data derived from seeds. After heterologous expression in Escherichia coli, partially purified NsTPS1 converted GDP to γ-terpinene. NsTPS1 is the first functionally characterized terpene synthase from N. sativa and displays a higher similarity to other terpene synthases from Ranunculaceae than known γ-terpinene synthases from more distant plant species. Characterization of NsTPS1 elucidates the first dedicated step in the biosynthesis of thymoquinone in N. sativa and paves the way towards metabolic engineering for high-level thymoquinone production.


Assuntos
Nigella sativa , Óleos Voláteis , Monoterpenos Cicloexânicos , Sementes
4.
Int J Mol Sci ; 22(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34681782

RESUMO

Thyme species are a good source of thymol and carvacrol, which play a key role in controlling diseases. For the first time, the expression patterns of γ-terpinene synthase (TPS2), CYP71D178, and CYP71D180 genes and the amount of phenolics compounds were evaluated in T. migricus and T. daenensis after different methyl jasmonate (MeJA) treatments. The highest thymol and carvacrol contents were observed in T. migricus (86.27%) and T. daenensis (17.87%) at MeJA 100 µM, which was consistent with the expression patterns of the three investigated genes. All species treated showed high total phenolic and flavonoid content compared to control plants for which the highest amounts were observed in T. vulgaris treated with 100 µM and 10 µM MeJA. Furthermore, in the 100 µM MeJA treatment, the relative expression of TPS2 and CYP71D178 in T. migricus increased 7.47 and 9.86-fold compared with the control, respectively. The highest level of CYP71D180 transcripts (5.15-fold) was also observed for T. daenensis treated. This finding highlights the notion that thymol was known as the dominant component of the essential oil rather than carvacrol in diffident thyme species. This implies that MeJA at different concentrations influenced metabolic pathways and induced expression changes, resulting in a rise in essential oil levels.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Cimenos/metabolismo , Oxilipinas/farmacologia , Compostos Fitoquímicos , Timol/metabolismo , Thymus (Planta) , Vias Biossintéticas/efeitos dos fármacos , Vias Biossintéticas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Irã (Geográfico) , Compostos Fitoquímicos/genética , Compostos Fitoquímicos/metabolismo , Especificidade da Espécie , Thymus (Planta)/química , Thymus (Planta)/efeitos dos fármacos , Thymus (Planta)/genética , Thymus (Planta)/metabolismo
5.
Atmos Chem Phys ; 20(8): 4637-4665, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33193752

RESUMO

This study provides a detailed characterization of stratocumulus clearings off the US West Coast using remote sensing, reanalysis, and airborne in situ data. Ten years (2009-2018) of Geostationary Operational Environmental Satellite (GOES) imagery data are used to quantify the monthly frequency, growth rate of total area (GRArea), and dimensional characteristics of 306 total clearings. While there is interannual variability, the summer (winter) months experienced the most (least) clearing events, with the lowest cloud fractions being in close proximity to coastal topographical features along the central to northern coast of California, including especially just south of Cape Mendocino and Cape Blanco. From 09:00 to 18:00 (PST), the median length, width, and area of clearings increased from 680 to 1231, 193 to 443, and ~ 67000 to ~ 250000km2, respectively. Machine learning was applied to identify the most influential factors governing the GRArea of clearings between 09:00 and 12:00PST, which is the time frame of most rapid clearing expansion. The results from gradient-boosted regression tree (GBRT) modeling revealed that air temperature at 850 hPa (T 850), specific humidity at 950 hPa (q 950), sea surface temperature (SST), and anomaly in mean sea level pressure (MSLPanom) were probably most impactful in enhancing GRArea using two scoring schemes. Clearings have distinguishing features such as an enhanced Pacific high shifted more towards northern California, offshore air that is warm and dry, stronger coastal surface winds, enhanced lower-tropospheric static stability, and increased subsidence. Although clearings are associated obviously with reduced cloud fraction where they reside, the domain-averaged cloud albedo was actually slightly higher on clearing days as compared to non-clearing days. To validate speculated processes linking environmental parameters to clearing growth rates based on satellite and reanalysis data, airborne data from three case flights were examined. Measurements were compared on both sides of the clear-cloudy border of clearings at multiple altitudes in the boundary layer and free troposphere, with results helping to support links suggested by this study's model simulations. More specifically, airborne data revealed the influence of the coastal low-level jet and extensive horizontal shear at cloud-relevant altitudes that promoted mixing between clear and cloudy air. Vertical profile data provide support for warm and dry air in the free troposphere, additionally promoting expansion of clearings. Airborne data revealed greater evidence of sea salt in clouds on clearing days, pointing to a possible role for, or simply the presence of, this aerosol type in clearing areas coincident with stronger coastal winds.

6.
Sci Rep ; 10(1): 19698, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184344

RESUMO

Due to the accumulation of various useful traits over evolutionary time, emmer wheat (Triticum turgidum subsp. dicoccum and dicoccoides, 2n = 4x = 28; AABB), durum wheat (T. turgidum subsp. durum, 2n = 4x = 28; AABB), T. timopheevii (2n = 4x = 28; AAGG) and D genome containing Aegilops species offer excellent sources of novel variation for the improvement of bread wheat (T. aestivum L., AABBDD). Here, we made 192 different cross combinations between diverse genotypes of wheat and Aegilops species including emmer wheat × Ae. tauschii (2n = DD or DDDD), durum wheat × Ae. tauschii, T. timopheevii × Ae. tauschii, Ae. crassa × durum wheat, Ae. cylindrica × durum wheat and Ae. ventricosa × durum wheat in the field over three successive years. We successfully recovered 56 different synthetic hexaploid and octaploid F2 lines with AABBDD, AABBDDDD, AAGGDD, D1D1XcrXcrAABB, DcDcCcCcAABB and DvDvNvNvAABB genomes via in vitro rescue of F1 embryos and spontaneous production of F2 seeds on the Fl plants. Cytogenetic analysis of F2 lines showed that the produced synthetic wheat lines were generally promising stable amphiploids. Contribution of D genome bearing Aegilops and the less-investigated emmer wheat genotypes as parents in the crosses resulted in synthetic amphiploids which are a valuable resource for bread wheat breeding.


Assuntos
Aegilops/crescimento & desenvolvimento , Melhoramento Vegetal/métodos , Triticum/crescimento & desenvolvimento , Aegilops/genética , Cruzamentos Genéticos , Análise Citogenética , Evolução Molecular , Variação Genética , Genótipo , Poliploidia , Triticum/classificação , Triticum/genética
7.
Magn Reson Imaging ; 73: 45-54, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32828985

RESUMO

PURPOSE: To develop a fast and accurate convolutional neural network based method for segmentation of thalamic nuclei. METHODS: A cascaded multi-planar scheme with a modified residual U-Net architecture was used to segment thalamic nuclei on conventional and white-matter-nulled (WMn) magnetization prepared rapid gradient echo (MPRAGE) data. A single network was optimized to work with images from healthy controls and patients with multiple sclerosis (MS) and essential tremor (ET), acquired at both 3 T and 7 T field strengths. WMn-MPRAGE images were manually delineated by a trained neuroradiologist using the Morel histological atlas as a guide to generate reference ground truth labels. Dice similarity coefficient and volume similarity index (VSI) were used to evaluate performance. Clinical utility was demonstrated by applying this method to study the effect of MS on thalamic nuclei atrophy. RESULTS: Segmentation of each thalamus into twelve nuclei was achieved in under a minute. For 7 T WMn-MPRAGE, the proposed method outperforms current state-of-the-art on patients with ET with statistically significant improvements in Dice for five nuclei (increase in the range of 0.05-0.18) and VSI for four nuclei (increase in the range of 0.05-0.19), while performing comparably for healthy and MS subjects. Dice and VSI achieved using 7 T WMn-MPRAGE data are comparable to those using 3 T WMn-MPRAGE data. For conventional MPRAGE, the proposed method shows a statistically significant Dice improvement in the range of 0.14-0.63 over FreeSurfer for all nuclei and disease types. Effect of noise on network performance shows robustness to images with SNR as low as half the baseline SNR. Atrophy of four thalamic nuclei and whole thalamus was observed for MS patients compared to healthy control subjects, after controlling for the effect of parallel imaging, intracranial volume, gender, and age (p < 0.004). CONCLUSION: The proposed segmentation method is fast, accurate, performs well across disease types and field strengths, and shows great potential for improving our understanding of thalamic nuclei involvement in neurological diseases.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Núcleos Talâmicos/diagnóstico por imagem , Automação , Estudos de Casos e Controles , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/patologia , Feminino , Humanos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Núcleos Talâmicos/patologia , Adulto Jovem
8.
Plant Physiol Biochem ; 142: 43-52, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31272034

RESUMO

Yarrow (Achillea millefolium) is a medicinal plant from the Asteracea which biosynthesize different secondary metabolites especially terpenes and phenylpropanoids. To improve our understanding of the regulatory mechanisms behind the biosynthesis of these compounds we analyzed the expression of some genes associated with the biosynthesis of terpenes and phenylpropanoids in different tissues and in response to trans-cinnamic acid (tCA) as an inhibitor of PAL activity. Isolation and expression analysis of DXR, GPPS, PAL and CHS genes together with linalool synthase (LIS) as monoterpene synthase was conducted in different developmental stages of leaves, flowers and in response to trans-cinnamic acid (tCA). Differential expression of these genes observed in different tissues. tCA up-regulated the biosynthetic genes of monterpenes and down-regulated the biosynthetic genes of phenylpropanoids. Gene expression analysis in intact leaves and leaves without glandular trichomes showed that DXR, LIS, PAL and CHS are highly expressed in glandular trichomes while GPPS expressed ubiquitously. Analysis of essential oils composition showed that sesquiterpenes and monoterpenes are main compounds; in which from 57 identified compounds the highest were germacreneD (% 11.5), guaiol (%10.38), spatulenol (%8.73) and caryophyllene oxide (%7.48).


Assuntos
Achillea/genética , Achillea/metabolismo , Fenilpropionatos/metabolismo , Proteínas de Plantas/genética , Terpenos/metabolismo , Achillea/química , Achillea/efeitos dos fármacos , Aciltransferases/genética , Aciltransferases/metabolismo , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/metabolismo , Vias Biossintéticas , Cinamatos/farmacologia , Farnesiltranstransferase/genética , Farnesiltranstransferase/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica de Plantas , Hidroliases/genética , Hidroliases/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Tricomas/genética , Tricomas/metabolismo
9.
Cell Mol Biol (Noisy-le-grand) ; 64(14): 89-95, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30511627

RESUMO

Digitalis nervosa is an important medicinal plant species belonging to the family of Scrophulariaceae that has the potential to be used for heart failure. 3ß-hydroxysteroid dehydrogenase (3ß-HSD) is a key gene in the biosynthesis of cardenolides for making digitalis effective compounds, hence identification of this gene is important for genetic engineering purposes towards increasing the yield of cardiac glycosides. In addition, mRNA-like non-coding RNAs (mlncRNAs), a class of long non coding RNAs, play key roles in various biological processes and may affect cardenolides pathway in digitalis plants.  In the present work, full sequence of 3ß-HSD was isolated from Digitalis nervosa. Gene expression patterns of 3ß-HSD along with three mlncRNAs including mlncRNA23, mlncRNA28 and mlncRNA30 were studied and the results indicated that they are differentially expressed in different tissues including roots, stems and leaves, with the highest expression levels in leaves.  Moreover, the transcript levels of these genes affected by the cold and drought stresses. The results obtained from the present study is important in order to understand the potential role of mlncRNAs in digitalis plants, especially in response to abiotic stresses.


Assuntos
17-Hidroxiesteroide Desidrogenases/genética , Digitalis/enzimologia , Digitalis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , RNA Longo não Codificante/genética , Estresse Fisiológico/genética , 17-Hidroxiesteroide Desidrogenases/química , 17-Hidroxiesteroide Desidrogenases/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Vias Biossintéticas/genética , Cardenolídeos/química , Cardenolídeos/metabolismo , Temperatura Baixa , Digitalis/fisiologia , Secas , Especificidade de Órgãos/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Chem Pharm Bull (Tokyo) ; 66(4): 423-426, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29607907

RESUMO

Hyperlipidemia is known as an elevation of plasma lipid components. It contributes significantly to atherosclerosis which is one of the most important causative factors in cardiovascular diseases. Agents that cause a dramatic decrease in serum lipid levels are of great value in the treatment of cardiovascular diseases. For this purpose, a new series of benzimidazole propyl carboxamide benzophenone derivatives have been synthesized (7, 8, and 9). These compounds were tested in vivo to evaluate their potential hypolipidemic activity using Triton WR-1339 induced hyperlipidemic rats. All the synthesized compounds have proved to be highly biologically active, with compound 9 being the most active derivative.


Assuntos
Benzimidazóis/farmacologia , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/farmacologia , Animais , Benzimidazóis/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hiperlipidemias/induzido quimicamente , Hipolipemiantes/síntese química , Hipolipemiantes/química , Injeções Intraperitoneais , Masculino , Estrutura Molecular , Polietilenoglicóis/administração & dosagem , Ratos , Ratos Wistar , Relação Estrutura-Atividade
11.
Plant Physiol Biochem ; 115: 152-162, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28365519

RESUMO

Thyme (Thymus vulgaris L.) is known to produce a variety of phenolic monoterpenes such as thymol and carvacrol. Thymol and carvacrol are health-promoting, biocide and antitoxin compounds and have been considered as the main constituents of essential oils in T. vulgaris. To improve our understanding of the regulation of monoterpene biosynthesis in thyme, the expression of genes related to thymol and carvacrol biosynthesis in different tissues and in response to abiotic elicitors was analyzed. Methyl jasmonate (MeJA), salicylic acid (SA), trans-cinnamic acid (tCA) and UV-C irradiation were applied to T. vulgare leaves and transcript levels of early (DXR) and late (TvTPS1, CYP71D178 and CYP71D180) biosynthetic genes of thymol and carvacrol were measured. The results showed that early step and late step genes in thymol/carvacrol biosynthesis are differentially regulated. DXR was not found to be exclusively expressed in glandular trichomes; in contrast, biosynthetic genes including γ-terpinene synthase (TvTPS1) and two cytochrome P450s, CYP71D178 and CYP71D180, were preferentially expressed in glandular secretory trichomes. The high expression of late biosynthetic genes in glandular trichomes, which also contain the highest concentration of thymol and carvacrol, suggests that glandular trichomes are the structure in which thymol/carvacrol biosynthesis and accumulation occur. Our results indicate that in addition to abiotic elicitors, developmental and spatial factors also play a key role in the biosynthesis of thymol and carvacrol, most likely relating to glandular trichome density and/or activity. Hence optimization of these factors could be considered as a useful strategy to achieve high yield of valuable compounds in T. vulgare or other closely related plant species.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Monoterpenos/metabolismo , Timol/metabolismo , Thymus (Planta)/metabolismo , Cimenos , Flores/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Estrutura Molecular , Monoterpenos/química , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Timol/química , Transcriptoma , Tricomas/fisiologia
12.
Environ Sci Pollut Res Int ; 24(13): 12261-12272, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28357789

RESUMO

Morphological and biochemical responses of feverfew plants exposed to low (5 µM) and high (35 and 70 µM) levels of Cd or Cu were investigated. Increasing metal supply notably reduced the plant biomass. Elevated Cd and Cu levels also resulted in an increase in the leaf proline content. Besides, decrease in ascorbic acid (AsA) and glutathione (GSH) contents was similar in the leaves of Cd- and Cu-treated plants, indicating altered biosynthesis of AsA and GSH under metal excess. High metal doses stimulated increase in antioxidative enzyme activities that could be related to elevated hydrogen peroxide (H2O2) content and subsequent lipid peroxidation. Cd was typically more accumulated in shoots and roots than Cu, leading to higher translocation factor at high Cd doses. In terms of essential oil content, it seems that Cd had an inhibitory effect during the experiment, whereas Cu was found to stimulate it only at 5 µM. Furthermore, high Cd supply enhanced the relative proportion of monoterpene hydrocarbons, while Cu increased the proportion of sesquiterpenes, especially at 5 µM. This result provides the first evidence of the response of feverfew plants to Cd or Cu by associating stress-related responses with changes in terpenoids.


Assuntos
Cádmio/metabolismo , Cobre/metabolismo , Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/metabolismo , Tanacetum parthenium , Terpenos/metabolismo
13.
Appl Microbiol Biotechnol ; 100(3): 1041-1059, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26567019

RESUMO

Sesquiterpene lactones (SLs) are one of the most diverse groups of secondary metabolites that mainly have been observed in the Asteraceae. They are composed of a C15 skeleton bearing functional groups, e.g., hydroxy, keto, or epoxy. Sesquiterpene lactones have been shown to display several biological activities; hence, their therapeutic effects are indispensable. To overcome low yield of sesquiterpene lactone content in native plants, manipulation of their biosynthetic pathway(s) has become an interesting approach for many researchers. Several genetic engineering strategies have been used in plants or microbial systems for elucidation of the biosynthetic pathway and high-level production of sesquiterpene lactones. Here, we will introduce ongoing research and perspectives about the manipulation of sesquiterpene lactone biosynthesis by various non-traditional metabolic engineering strategies, along with successful examples of high-yield production of sesquiterpene lactones mainly focused on parthenolide and artemisinin in plants and microorganisms.


Assuntos
Artemisininas/metabolismo , Bactérias/metabolismo , Plantas/genética , Plantas/metabolismo , Sesquiterpenos/metabolismo , Bactérias/genética , Vias Biossintéticas , Engenharia Metabólica
14.
Plant Cell Rep ; 34(11): 1909-18, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26183953

RESUMO

KEY MESSAGE: Up-regulation of germacrene A synthase and down-regulation of parthenolide hydroxylase genes play key role in parthenolide accumulation of feverfew plants treated with methyl jasmonate and salicylic acid. Parthenolide is an important sesquiterpene lactone due to its anti-migraine and anti-cancer properties. Parthenolide amount was quantified by high-performance liquid chromatography after foliar application of methyl jasmonate (100 µM) or salicylic acid (1.0 mM) on feverfew leaves in time course experiment (3-96 h). Results indicate that exogenous application of methyl jasmonate or salicylic acid activated parthenolide biosynthesis. Parthenolide content reached its highest amount at 24 h after methyl jasmonate or salicylic acid treatments, which were 3.1- and 1.96-fold higher than control plants, respectively. Parthenolide transiently increased due to methyl jasmonate or salicylic acid treatments until 24 h, but did not show significant difference compared with control plants at 48 and 96 h time points in both treatments. Also, the transcript levels of early pathway (upstream) genes of terpene biosynthesis including 3-hydroxy-3-methylglutaryl-coenzyme A reductase, 1-deoxy-D-xylulose-5-phosphate reductoisomerase and hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase and the biosynthetic genes of parthenolide including germacrene A synthase, germacrene A oxidase, costunolide synthase and parthenolide synthase were increased by methyl jasmonate and salicylic acid treatments, but with different intensity. The transcriptional levels of these genes were higher in methyl jasmonate-treated plants than salicylic acid-treated plants. Parthenolide content measurements along with expression pattern analysis of the aforementioned genes and parthenolide hydroxylase as side branch gene of parthenolide suggest that the expression patterns of early pathway genes were not directly consistent with parthenolide accumulation pattern; hence, parthenolide accumulation is probably further modulated by the expression of its biosynthetic genes, especially germacrene A synthase and also its side branch gene, parthenolide hydroxylase.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oxilipinas/farmacologia , Ácido Salicílico/farmacologia , Sesquiterpenos/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Tanacetum parthenium/efeitos dos fármacos , Tanacetum parthenium/genética , Tanacetum parthenium/metabolismo
15.
Physiol Mol Biol Plants ; 19(2): 189-98, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24431486

RESUMO

The response of photosynthesis parameters, catalase, superoxide dismutase and peroxidase activity, malondialdehyde, proline, chlorophyll, yield and yield components to foliar application of calcium and simulated acid rain in wheat were investigated. Foliar treatment of calcium led to significant increases in the photosynthesis rate, transpiration rate, stomatal conductance, proline, chlorophyll, yield and yield components in plants subjected to acid rain. Antioxidant enzyme activity and lipid peroxidation in the wheat leaves decreased because of calcium foliar application. Calcium hindered degradation of the rubisco subunits under acid rain treatment compared with water-treated plants. Results suggest that acid rain induces the production of free radicals resulting in lipid peroxidation of the cell membrane so that significant increase in antioxidant enzyme activity was observed. In addition, photosynthetic parameters i.e. photosynthesis rate, transpiration rate and stomatal conductance were drastically suppressed by acid rain. The cellular damage caused by free radicals might be reduced or prevented by a protective metabolism including antioxidative enzymes and calcium. We report that foliar application of calcium before acid rain may ameliorate the adverse effects of acid rain in wheat plants.

16.
PLoS One ; 6(8): e23255, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21858047

RESUMO

The sesquiterpene costunolide has a broad range of biological activities and is the parent compound for many other biologically active sesquiterpenes such as parthenolide. Two enzymes of the pathway leading to costunolide have been previously characterized: germacrene A synthase (GAS) and germacrene A oxidase (GAO), which together catalyse the biosynthesis of germacra-1(10),4,11(13)-trien-12-oic acid. However, the gene responsible for the last step toward costunolide has not been characterized until now. Here we show that chicory costunolide synthase (CiCOS), CYP71BL3, can catalyse the oxidation of germacra-1(10),4,11(13)-trien-12-oic acid to yield costunolide. Co-expression of feverfew GAS (TpGAS), chicory GAO (CiGAO), and chicory COS (CiCOS) in yeast resulted in the biosynthesis of costunolide. The catalytic activity of TpGAS, CiGAO and CiCOS was also verified in planta by transient expression in Nicotiana benthamiana. Mitochondrial targeting of TpGAS resulted in a significant increase in the production of germacrene A compared with the native cytosolic targeting. When the N. benthamiana leaves were co-infiltrated with TpGAS and CiGAO, germacrene A almost completely disappeared as a result of the presence of CiGAO. Transient expression of TpGAS, CiGAO and CiCOS in N. benthamiana leaves resulted in costunolide production of up to 60 ng.g(-1) FW. In addition, two new compounds were formed that were identified as costunolide-glutathione and costunolide-cysteine conjugates.


Assuntos
Vias Biossintéticas , Nicotiana/metabolismo , Sesquiterpenos/metabolismo , Leveduras/metabolismo , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Cichorium intybus/enzimologia , Cichorium intybus/genética , Cromatografia Líquida/métodos , Cisteína/química , Cisteína/metabolismo , Sistema Enzimático do Citocromo P-450/classificação , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Glutationa/química , Glutationa/metabolismo , Espectrometria de Massas/métodos , Dados de Sequência Molecular , Estrutura Molecular , Oxirredução , Oxirredutases/classificação , Oxirredutases/genética , Oxirredutases/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sesquiterpenos/química , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/metabolismo , Tanacetum parthenium/enzimologia , Tanacetum parthenium/genética , Nicotiana/genética , Transformação Genética , Leveduras/genética
17.
Phytochemistry ; 72(14-15): 1739-50, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21620424

RESUMO

Feverfew (Tanacetum parthenium) is a perennial medicinal herb and is a rich source of sesquiterpene lactones. Parthenolide is the main sesquiterpene lactone in feverfew and has attracted attention because of its medicinal potential for treatment of migraine and cancer. In the present work the parthenolide content in different tissues and developmental stages of feverfew was analyzed to study the timing and localization of parthenolide biosynthesis. The strongest accumulating tissue was subsequently used to isolate sesquiterpene synthases with the goal to isolate the gene encoding the first dedicated step in parthenolide biosynthesis. This led to the isolation and charachterization of a germacrene A synthase (TpGAS) and an (E)-ß-caryophyllene synthase (TpCarS). Transcript level patterns of both sesquiterpene synthases were analyzed in different tissues and glandular trichomes. Although TpGAS was expressed in all aerial tissues, the highest expression was observed in tissues that contain high concentrations of parthenolide and in flowers the highest expression was observed in the biosynthetically most active stages of flower development. The high expression of TpGAS in glandular trichomes which also contain the highest concentration of parthenolide, suggests that glandular trichomes are the secretory tissues where parthenolide biosynthesis and accumulation occur.


Assuntos
Alquil e Aril Transferases/metabolismo , Anti-Inflamatórios não Esteroides/metabolismo , Extratos Vegetais/química , Sesquiterpenos/metabolismo , Tanacetum parthenium/metabolismo , Alquil e Aril Transferases/genética , Sequência de Aminoácidos , Anti-Inflamatórios não Esteroides/análise , DNA Complementar/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Flores/genética , Frutas/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Especificidade de Órgãos , Filogenia , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Caules de Planta/genética , Plantas Medicinais , RNA Mensageiro/genética , RNA de Plantas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Sesquiterpenos/análise , Tanacetum parthenium/química , Tanacetum parthenium/enzimologia , Tanacetum parthenium/crescimento & desenvolvimento
18.
J Matern Fetal Neonatal Med ; 24(1): 104-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20528216

RESUMO

OBJECTIVE: Postpartum depression is a common complication of childbirth, and its prevention is an important public-health issue because of its negative effects on mother, infant, and family. The present randomized, double-blind, placebo-controlled trial was conducted to examine the effect of prenatal selenium supplementation on the postpartum depression level in Iranian women. DESIGN: A total of 166 primigravid pregnant women in the first trimester of pregnancy, were randomized to receive 100 µg of selenium (n = 83) or a placebo (n = 83) per day until delivery. The symptoms of postpartum depression were evaluated during the eight weeks following delivery by means of the Edinburgh Postnatal Depression Scale (EPDS). Serum selenium concentrations were measured at baseline and at the end of study. RESULTS: There was no significant difference in demographic characteristics and perceived social support between the selenium and control groups at baseline (p > 0.05). There were 22 drop-outs in the selenium-supplemented group and 19 in the placebo group. Forty-four women in the selenium group and 41 women in the placebo group completed the trial and the EPDS questionnaire. Selenium supplementation was associated with a significant increase in mean serum selenium concentration at term (p < 0.001) but remained unchanged in the control group. The mean EPDS score in the selenium group was significantly lower than that of the control group (p < 0.05). CONCLUSION: These findings suggest that supplementation with selenium during pregnancy might be an effective approach for the prevention of postpartum depression.


Assuntos
Depressão Pós-Parto/prevenção & controle , Selênio/uso terapêutico , Oligoelementos/uso terapêutico , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Irã (Geográfico) , Gravidez , Selênio/sangue , Adulto Jovem
19.
Stroke ; 41(1): e3-e10, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19926844

RESUMO

BACKGROUND AND PURPOSE: The epidemiology of stroke and its subtypes in the Middle East is unclear. Most previous studies have been performed in Western countries, and incidence rates are unlikely to apply in the Middle East. We aimed to determine the incidence of stroke in Mashhad, northeastern Iran. METHODS: During a 12-month period (2006-2007), we prospectively ascertained all strokes occurring in a population of 450 229. Multiple overlapping sources were used to identify people with stroke. A large number of volunteers assisted in finding stroke patients not admitted to hospital. Potential cases were reviewed by a group of stroke experts before inclusion. RESULTS: A total of 624 first-ever strokes occurred during the study period, 98.4% undergoing imaging. Despite a relatively low crude annual incidence rate of first-ever stroke FES (139; 95% CI, 128 to 149) per 100 000 residents, rates adjusted to the European population aged 45 to 84 years were higher than in most other countries: 616 (95% CI, 567 to 664) for ischemic stroke, 94 (95% CI, 75 to 113) for intracerebral hemorrhage, and 12 (95% CI, 5 to 19) for subarachnoid hemorrhage. Age-specific stroke incidence was higher in younger patients than is typically seen in Western countries. Comparison of age-specific incidence rates between regions revealed that stroke in Mashhad occurs approximately 1 decade earlier than in Western countries. CONCLUSIONS: The results of this study provide evidence that the incidence of stroke in Iran is considerably greater than in most Western countries, with stroke occurring at younger ages. Ischemic stroke incidence was also considerably greater than reported in other regions.


Assuntos
Acidente Vascular Cerebral/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Acessibilidade aos Serviços de Saúde/tendências , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Oriente Médio/epidemiologia , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico
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