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The widespread use of pesticides in agriculture remains a matter of major concern, prompting a critical need for alternative and sustainable practices. To address this, the use of lipid-derived molecules as elicitors to induce defence responses in grapevine plants was accessed. A Plasmopara viticola fatty acid (FA), eicosapentaenoic acid (EPA) naturally present in oomycetes, but absent in plants, was applied by foliar spraying to the leaves of the susceptible grapevine cultivar (Vitis vinifera cv. Trincadeira), while a host lipid derived phytohormone, jasmonic acid (JA) was used as a molecule known to trigger host defence. Their potential as defence triggers was assessed by analysing the expression of a set of genes related to grapevine defence and evaluating the FA modulation upon elicitation. JA prompted grapevine immunity, altering lipid metabolism and up-regulating the expression of several defence genes. EPA also induced a myriad of responses to the levels typically observed in tolerant plants. Its application activated the transcription of defence gene's regulators, pathogen-related genes and genes involved in phytoalexins biosynthesis. Moreover, EPA application resulted in the alteration of the leaf FA profile, likely by impacting biosynthetic, unsaturation and turnover processes. Although both molecules were able to trigger grapevine defence mechanisms, EPA induced a more robust and prolonged response. This finding establishes EPA as a promising elicitor for an effectively managing grapevine downy mildew diseases.
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Ciclopentanos , Ácido Eicosapentaenoico , Oomicetos , Oxilipinas , Vitis , Vitis/microbiologia , Vitis/metabolismo , Vitis/genética , Vitis/imunologia , Vitis/efeitos dos fármacos , Ácido Eicosapentaenoico/metabolismo , Oomicetos/fisiologia , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Imunidade Vegetal/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/imunologia , Folhas de Planta/microbiologiaRESUMO
The aim of this study was to investigate the correlation between depressive symptoms and the occurrence of oral mucositis in children with oncological diseases treated at a reference hospital. This was a cross-sectional study conducted with individuals aged 4 to 18 years, diagnosed with primary neoplasms. Data was collected by using a questionnaire that assessed the degree of oral mucositis according to the World Health Organization index, the risk of oral mucositis according to the Child's International Mucositis Evaluation Scale, and depressive symptoms using the Children's Depression Inventory. The data were analyzed and subjected to Spearman's correlation, chi-square test, and Fisher's exact test, considering p<0.05. A statistically significant correlation was observed between depressive symptoms and the degree of oral mucositis (p = 0.044), and also between the "pain" variable within the risk of oral mucositis and depressive symptoms (p = 0.021). Based on the findings, it can be inferred that oral mucositis may be associated with the development of depressive symptoms and may be influenced by the individual's hospitalization, thereby affecting the quality of life of pediatric patients.
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Depressão , Neoplasias , Qualidade de Vida , Estomatite , Humanos , Estomatite/psicologia , Estomatite/etiologia , Criança , Estudos Transversais , Masculino , Feminino , Adolescente , Pré-Escolar , Depressão/psicologia , Neoplasias/complicações , Neoplasias/psicologia , Índice de Gravidade de Doença , Inquéritos e Questionários , Estatísticas não Paramétricas , Fatores de RiscoRESUMO
Oomycetes are filamentous organisms that resemble fungi in terms of morphology and life cycle, primarily due to convergent evolution. The success of pathogenic oomycetes lies in their ability to adapt and overcome host resistance, occasionally transitioning to new hosts. During plant infection, these organisms secrete effector proteins and other compounds during plant infection, as a molecular arsenal that contributes to their pathogenic success. Genomic sequencing, transcriptomic analysis, and proteomic studies have revealed highly diverse effector repertoires among different oomycete pathogens, highlighting their adaptability and evolution potential.The obligate biotrophic oomycete Plasmopara viticola affects grapevine plants (Vitis vinifera L.) causing the downy mildew disease, with significant economic impact. This disease is devastating in Europe, leading to substantial production losses. Even though Plasmopara viticola is a well-known pathogen, to date there are scarce reviews summarising pathogenicity, virulence, the genetics and molecular mechanisms of interaction with grapevine.This review aims to explore the current knowledge of the infection strategy, lifecycle, effector molecules, and pathogenicity of Plasmopara viticola. The recent sequencing of the Plasmopara viticola genome has provided new insights into understanding the infection strategies employed by this pathogen. Additionally, we will highlight the contributions of omics technologies in unravelling the ongoing evolution of this oomycete, including the first in-plant proteome analysis of the pathogen.
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Oomicetos , Doenças das Plantas , Vitis , Oomicetos/patogenicidade , Oomicetos/fisiologia , Doenças das Plantas/microbiologia , Vitis/microbiologia , Vitis/genética , Virulência , Evolução Biológica , Interações Hospedeiro-PatógenoRESUMO
Purpose: This study aimed to compare the surface roughness among 3 types of glass ionomers (GI) before (no polishing) and after polishing with three different materials. Methods: 20 discs for each GI group were obtained (A-Ionolux; B-IonoStar Plus; C-Ketac). Those groups were subdivided according to finishing and polishing: subgroups 1 (control) - no polishing, 2 - polishing with prophylactic brush and pumice paste, 3 - Enhance tips with water, and 4 - Sof-Lex system with Easy Glaze and polymerization. For each disc face, the total distance analyzed was 2.88cm (6x48mm). Then, the roughness was compared using the Kruskal-Wallis with Bonferroni test, with significant data if p<0.05. Results: The mean of roughness within Group A was lower for subgroup 4 (1.07±0.54 µm) and higher for subgroup 2 (2.33±1.17 µm). Within group B, B4 had the lowest mean of roughness (0.93±0.38 µm) and B2 (1.24 ± 0.78 µm) the highest roughness. Within group C, Group C4 had the lowest mean roughness value (0.84±0.54 µm), and C3 had the highest mean (2.48±1.05 µm). After polishing, subgroup 4 had the general lowest values for surface roughness (mean Ra 0.95), followed by subgroup 1 (Ra=1.27), subgroup 2 (Ra=1.89), and higher values for subgroup 3. All intragroup analysis for A, B, and C were statistically significant. Group A presented the highest roughness (p<0.05), and no statistically significant evidence existed between groups B and C (p>0.05). Conclusion: The reduction of the roughness of the materials is dependent on their composition and the polishing and finishing techniques applied.
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Connecting vehicles to the Internet is an emerging challenge of wireless networks. There are two competing methods for achieving this. First, the wireless local area network (WLAN) approach is based on the IEEE 802.11p standard (in its European version called ETSI ITS-G5) created for Cooperative-Intelligent Transportation System applications. Second, the cellular network approach is based on LTE/5G technologies which have been exploited in recent years to support vehicular applications. Advantages such as high bandwidth, high coverage and high reliability make cellular networks a great option for the vehicular environment. This article describes two datasets that support the analysis of WLAN (ETSI ITS-G5) and Cellular (LTE/5G) technologies in a real vehicular and road environment. The two datasets summarize the results obtained in a collection of network performance tests performed in the city of Aveiro, Portugal. In these tests, a set of vehicles (8 On-Board Units) moved randomly around the city, passing near a group of stationary nodes (11 Road-Side Units) uploading data to a server. In the WLAN dataset, data was sent using the ETSI ITS-G5 technology, whereas, in the Cellular dataset, data was sent using LTE/5G technologies. While testing, location, signal quality, and network performance data (achieved throughput, jitter, etc.) were collected. This dataset can support a realistic analysis of WLAN and Cellular performance in an environment that is not only vehicular but also urban, with obstacles and interference.
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Abstract The aim of this study was to investigate the correlation between depressive symptoms and the occurrence of oral mucositis in children with oncological diseases treated at a reference hospital. This was a cross-sectional study conducted with individuals aged 4 to 18 years, diagnosed with primary neoplasms. Data was collected by using a questionnaire that assessed the degree of oral mucositis according to the World Health Organization index, the risk of oral mucositis according to the Child's International Mucositis Evaluation Scale, and depressive symptoms using the Children's Depression Inventory. The data were analyzed and subjected to Spearman's correlation, chi-square test, and Fisher's exact test, considering p<0.05. A statistically significant correlation was observed between depressive symptoms and the degree of oral mucositis (p = 0.044), and also between the "pain" variable within the risk of oral mucositis and depressive symptoms (p = 0.021). Based on the findings, it can be inferred that oral mucositis may be associated with the development of depressive symptoms and may be influenced by the individual's hospitalization, thereby affecting the quality of life of pediatric patients.
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Phlomis purpurea grows spontaneously in the southern Iberian Peninsula, namely in cork oak (Quercus suber) forests. In a previous transcriptome analysis, we reported on its immunity against Phytophthora cinnamomi. However, little is known about the involvement of secondary metabolites in the P. purpurea defense response. It is known, though, that root exudates are toxic to this pathogen. To understand the involvement of secondary metabolites in the defense of P. purpurea, a metabolome analysis was performed using the leaves and roots of plants challenged with the pathogen for over 72 h. The putatively identified compounds were constitutively produced. Alkaloids, fatty acids, flavonoids, glucosinolates, polyketides, prenol lipids, phenylpropanoids, sterols, and terpenoids were differentially produced in these leaves and roots along the experiment timescale. It must be emphasized that the constitutive production of taurine in leaves and its increase soon after challenging suggests its role in P. purpurea immunity against the stress imposed by the oomycete. The rapid increase in secondary metabolite production by this plant species accounts for a concerted action of multiple compounds and genes on the innate protection of Phlomis purpurea against Phytophthora cinnamomi. The combination of the metabolome with the transcriptome data previously disclosed confirms the mentioned innate immunity of this plant against a devastating pathogen. It suggests its potential as an antagonist in phytopathogens' biological control. Its application in green forestry/agriculture is therefore possible.
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The apoplast is the plant compartment present between the plasma membrane and the cuticle, comprised of the cell wall and the extracellular spaces where the "secretomes" are released and where the apoplastic fluid circulates. Within the many functions attributed to this compartment, its role in plant-pathogen interactions is irrefutable. It is the major point where plant and pathogen secretomes come in contact and several plant and pathogenic secreted proteins and small molecules present in this compartment are already cataloged in the literature. In plant-pathogen interactions, fatty acids and lipid molecules were shown to play a crucial role in the activation of plant immunity; however, the lipid composition of the apoplast is still a black box. Most of the studies performed to understand apoplast dynamics have used proteomic-based techniques; however, knowledge about apoplastic proteins involved in lipid metabolism and transport is still severely limited. In grapevine, only three studies have been published so far focusing on the characterization of this compartment and only one of them deals with grapevine-pathogen interaction. Here we refer to our recently established method for grapevine leaves' apoplastic fluid isolation and describe a direct methylation protocol for the analysis of apoplastic fluid fatty acids. We also point out a novel intracellular marker that may be used to assess apoplastic fluid purity.
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Ácidos Graxos , Vitis , Ácidos Graxos/metabolismo , Proteômica , Folhas de Planta/metabolismo , Espaço Extracelular/metabolismo , Proteínas de Plantas/metabolismo , Vitis/metabolismo , Doenças das PlantasRESUMO
Purpose: The aim of this study was to compare clinical periodontal conditions in HIV-positive people on HAART with an HIV-negative group, in addition to investigating factors associated with periodontitis in the entire sample. Methods: This was a cross-sectional study. Data were collected by oral clinical examination for the diagnosis of periodontitis, review of medical records, and application of a questionnaire containing personal data, deleterious habits, and oral hygiene habits for the other variables. The results were analyzed by Pearson's χ 2 test and Student's t-test. A logistic regression model was constructed for the multivariate analysis and periodontitis was defined as a dependent variable. The analysis was performed on the entire sample (HIV+ and HIV-) and also on the group consisting of only people living with HIV. Results: Individuals older than 43 years old and with HIV were more likely to develop moderate and severe periodontitis (47.80 and 4.84 times, respectively). When analyzing only HIV+, in addition to age (OR = 2.795; CI = 1.080-7.233), the use of nonnucleoside reverse transcriptase inhibitors (NNRTIs) (OR = 2.841; CI = 1.135-7.112) was also associated with moderate and severe periodontitis. Conclusion: It was possible to observe a higher prevalence of periodontitis among individuals with HIV, showing an association between the virus, advanced age, and moderate or severe periodontitis.
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Amid climate change, heatwave events are expected to increase in frequency and severity. As a result, yield losses in viticulture due to heatwave stress have increased over the years. As one of the most important crops in the world, an eco-friendly stress mitigation strategy is greatly needed. The present work aims to evaluate the physiological fitness improvement by two marine plant growth-promoting rhizobacteria consortia in Vitis vinifera cv. Antão Vaz under heatwave conditions. To assess the potential biophysical and biochemical thermal stress feedback amelioration, photochemical traits, pigment and fatty acid profiles, and osmotic and oxidative stress biomarkers were analysed. Bioaugmented grapevines exposed to heatwave stress presented a significantly enhanced photoprotection capability and higher thermo-stability, exhibiting a significantly lower dissipation energy flux than the non-inoculated plants. Additionally, one of the rhizobacterial consortia tested improved light-harvesting capabilities by increasing reaction centre availability and preserving photosynthetic efficiency. Rhizobacteria inoculation expressed an osmoprotectant promotion, revealed by the lower osmolyte concentration while maintaining leaf turgidity. Improved antioxidant mechanisms and membrane stability resulted in lowered lipid peroxidation product formation when compared to non-inoculated plants. Although the consortia were found to differ significantly in their effectiveness, these findings demonstrate that bioaugmentation induced significant heatwave stress tolerance and mitigation. This study revealed the promising usage of marine PGPR consortia to promote plant fitness and minimize heatwave impacts in grapevines.
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Grapevine is one of the most important fruit crops worldwide, being Portugal one of the top wine producers. It is well established that wine sensory characteristics from a particular region are defined by the physiological responses of the grapevine to its environment and thus, the concept of terroir in viticulture was established. Among all the factors that contribute to terroir definition, soil microorganisms play a major role from nutrient recycling to a drastic influence on plant fitness (growth and protection) and of course wine production. Soil microbiome from four different terroirs in Quinta dos Murças vineyard was analysed through long-read Oxford Nanopore sequencing. We have developed an analytical pipeline that allows the identification of function, ecologies, and indicator species based on long read sequencing data. The Douro vineyard was used as a case study, and we were able to establish microbiome signatures of each terroir.
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INTRODUCTION: The goal of this study was to assess the impact of COVID-19 on Portuguese dental students on their depression, anxiety, temporomandibular dysfunction, academic degree, and oral behaviors. METHODS: The target of this population study was to enroll third-, fourth-, and fifth-year students of the Integrated Master's degree in Dental Medicine at the Universidade Católica Portuguesa-Faculty of Dental Medicine (Viseu, Portugal) in the academic year 2021-2022. Temporomandibular disorders (TMD) symptoms, oral behaviors, anxiety, and depression were assessed using validated questionnaires. The variables under study were (a) age, gender, marital status, academic level, academic degree, medication, and any existing pathologies; (b) questions related to taste changes or thoughts that would indicate (or not) worsening psychological conditions (anxiety and depression). After data collection (Google Forms®), data were transferred to an Excel file and entered into SPSS® software. A chi-square test allowed the independence between ordinal or nominal variables. The Spearman correlation test was used to analyze the relationship between variables in the study (significant if p ≤ 0.05). RESULTS: 98.2% of the students answered the questionnaire. TMD had a prevalence of 35%, and anxiety and depression a prevalence of 29% and 24%, respectively. The results showed that the female gender was the most affected by psychological and temporomandibular disorders. Statistically significant correlations were identified between variables, such as gender and anxiety, TDM, and depression (respectively, p = 0.0001, p = 0.014, and p = 0.026); between TDM and anxiety and depression (respectively, p = 0.001 and p < 0.001); and between performing oral behaviors and TMD, anxiety, and depression (respectively, p = 0.0001, p = 0.0001, and p = 0.006). The variables, such as age and academic degree, did not establish a statistically significant relationship with TMD, oral behaviors, and the two psychological conditions. CONCLUSIONS: It was possible to conclude that there was a moderate prevalence of TMD, anxiety, and depression in the period studied. Moreover, a statistically significant relationship was found between TMD, anxiety, and depression with gender and frequency of OBs; however, no significant association was found for TMD, anxiety, and depression with the age of students and with the academic degree.
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Vitis vinifera L. is highly susceptible to the biotrophic pathogen Plasmopara viticola. To control the downy mildew disease, several phytochemicals are applied every season. Recent European Union requirements to reduce the use of chemicals in viticulture have made it crucial to use alternative and more sustainable approaches to control this disease. Our previous studies pinpoint the role of fatty acids and lipid signalling in the establishment of an incompatible interaction between grapevine and P. viticola. To further understand the mechanisms behind lipid involvement in an effective defence response we have analysed the expression of several genes related to lipid metabolism in three grapevine genotypes: Chardonnay (susceptible); Regent (tolerant), harbouring an Rpv3-1 resistance loci; and Sauvignac (resistant) that harbours a pyramid of Rpv12 and Rpv3-1 resistance loci. A highly aggressive P. viticola isolate was used (NW-10/16). Moreover, we have characterised the grapevine phospholipases C and D gene families and monitored fatty acid modulation during infection. Our results indicate that both susceptible and resistant grapevine hosts did not present wide fatty acid or gene expression modulation. The modulation of genes associated with lipid signalling and fatty acids seems to be specific to Regent, which raises the hypothesis of being specifically linked to the Rpv3 loci. In Sauvignac, the Rpv12 may be dominant concerning the defence response, and, thus, this genotype may present the activation of other pathways rather than lipid signalling.
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Oomicetos , Peronospora , Humanos , Resistência à Doença/genética , Oomicetos/fisiologia , Ácidos Graxos , LipídeosRESUMO
The apoplast is the first hub of plant-pathogen communication where pathogen effectors are recognized by plant defensive proteins and cell receptors, thus activating signal transduction pathways. As a result of this first contact, the host triggers a defense response that involves the modulation of extra- and intracellular proteins. In grapevine-pathogen interactions, little is known about the trafficking between extra- and intracellular spaces. Grapevine is an economically important crop that relies on heavy fungicide use to control several diseases, and a deeper knowledge on the activation of its immune response is crucial to define new control strategies. In this study, we focused on the first 6 h postinoculation with Plasmopara viticola to evaluate grapevine proteome modulation in the apoplast. The in planta P. viticola proteome was also assessed to enable a deeper understanding of plant-pathogen communication. Our results showed that several plant mechanisms are triggered in the tolerant grapevine cultivar Regent after inoculation, such as oomycete recognition, plant cell wall modifications, reactive oxygen species signaling, and secretion of proteins to disrupt oomycete structures. On the other hand, P. viticola proteins related to development and virulence were the most predominant. This pioneer study highlights the early dynamics of cellular communication in grapevine defense that leads to the successful establishment of an incompatible interaction.
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Oomicetos , Vitis , Proteoma , Folhas de Planta , Doenças das Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Resistência à DoençaRESUMO
Metabolomics involves the identification and quantification of metabolites to unravel the chemical footprints behind cellular regulatory processes and to decipher metabolic networks, opening new insights to understand the correlation between genes and metabolites. In plants, it is estimated the existence of hundreds of thousands of metabolites and the majority is still unknown. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) is a powerful analytical technique to tackle such challenges. The resolving power and sensitivity of this ultrahigh mass accuracy mass analyzer is such that a complex mixture, such as plant extracts, can be analyzed and thousands of metabolite signals can be detected simultaneously and distinguished based on the naturally abundant elemental isotopes. In this review, FT-ICR-MS-based plant metabolomics studies are described, emphasizing FT-ICR-MS increasing applications in plant science through targeted and untargeted approaches, allowing for a better understanding of plant development, responses to biotic and abiotic stresses, and the discovery of new natural nutraceutical compounds. Improved metabolite extraction protocols compatible with FT-ICR-MS, metabolite analysis methods and metabolite identification platforms are also explored as well as new in silico approaches. Most recent advances in MS imaging are also discussed.
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The osteolytic activity of odontogenic cysts and tumors is directly associated with their growth and aggressiveness. The influence of proteins expressed by epithelial and mesenchymal cells on this biological event differs between indolent cystic lesions, aggressive cystic lesions, and odontogenic tumors. The objective of this study was to compare the immunohistochemical expression of factors that stimulate (receptor activator of nuclear factor kappa-Β ligand - RANKL, cathepsin K - CatK and matrix metallopeptidase 8 - MMP-8) and inhibit (osteoprotegerin - OPG) osteoclastogenesis between dentigerous cyst (DC), glandular odontogenic cyst (GOC), odontogenic keratocyst (OKC), and ameloblastoma (AB). Paraffin-embedded sections of nine DCs, nine GOCs, 20 OKCs, 21 ABs, and four dental follicles (DFs) were subjected to immunohistochemistry. Immunoreactivity was analyzed semiquantitatively and quantitatively in epithelium and connective tissue, respectively. The proteins were immunoexpressed in epithelial and mesenchymal cells of all lesions studied. The expression of RANKL and CatK was higher in OKC, AB, and GOC (p<0.005). Higher expression of OPG was found in DF and DC compared to the other markers (p<0.005). MMP-8 expression was high in GOC and OKC. This study demonstrated the differential expression of factors that inhibit and stimulate bone resorption during the development of DC, GOC, OKC, and AB. Higher expression of RANKL and CatK was observed in more aggressive lesions. OPG appears to be one of the molecules responsible for the slower growth of DC.
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Ameloblastoma , Cisto Dentígero , Cistos Odontogênicos , Tumores Odontogênicos , Humanos , Cisto Dentígero/metabolismo , Cisto Dentígero/patologia , Metaloproteinase 8 da Matriz , Cistos Odontogênicos/patologia , Ameloblastoma/metabolismo , Ameloblastoma/patologia , Tumores Odontogênicos/patologiaRESUMO
Plasmopara viticola, an obligate biotrophic oomycete, is the causal agent of one of the most harmful grapevine diseases, downy mildew. Within this pathosystem, much information is gathered on the host, as characterization of pathogenicity and infection strategy of a biotrophic pathogen is quite challenging. Molecular insights into P. viticola development and pathogenicity are just beginning to be uncovered, mainly by transcriptomic studies. Plasmopara viticola proteome and secretome were only predicted based on transcriptome data. In this study, we have identified the in-planta proteome of P. viticola during infection of a susceptible ('Trincadeira') and a Rpv3-mediated resistance ('Regent') grapevine cultivar. Four hundred and twenty P. viticola proteins were identified on a label-free mass spectrometry-based approach of the apoplastic fluid of grapevine leaves. Overall, our study suggests that, in the compatible interaction, P. viticola manipulates salicylic-acid pathway and isoprenoid biosynthesis to enhance plant colonization. Furthermore, during the incompatible interaction, development-associated proteins increased while oxidoreductases protect P. viticola from ROS-associated plant defence mechanism. Up to our knowledge this is the first in-planta proteome characterization of this biotrophic pathogen, thus this study will open new insights into our understanding of this pathogen colonization strategy of both susceptible and Rpv3-mediated resistance grapevine genotypes.
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Oomicetos , Proteoma , Transcriptoma , Espectrometria de Massas , Resolução de ProblemasRESUMO
The increased use of antidepressants, along with their increased occurrence in aquatic environments, is of concern for marine organisms. Although these pharmaceutical compounds have been shown to negatively affect marine diatoms, their mode of action in these non-target, single-cell phototrophic organisms is yet unknown. Using a Fourier-transform ion cyclotron-resonance mass spectrometer (FT-ICR-MS) we evaluated the effects of fluoxetine in the metabolomics of the model diatom Phaeodactylum tricornutum, as well as the potential use of the identified metabolites as exposure biomarkers. Diatom growth was severely impaired after fluoxetine exposure, particularly in the highest dose tested, along with a down-regulation of photosynthetic and carbohydrate metabolisms. Notably, several mechanisms that are normally down-regulated by fluoxetine in mammal organisms were also down-regulated in diatoms (e.g., glycerolipid metabolism, phosphatidylinositol signalling pathway, vitamin metabolism, terpenoid backbone biosynthesis and serotonin remobilization metabolism). Additionally, the present work also identified a set of potential biomarkers of fluoxetine exposure that were up-regulated with increasing fluoxetine exposure concentration and are of high metabolic significance following the disclosed mode of action, reinforcing the use of metabolomics approaches in ecotoxicology.
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Despite well-established pathways and metabolites involved in grapevine-Plasmopara viticola interaction, information on the molecules involved in the first moments of pathogen contact with the leaf surface and their specific location is still missing. To understand and localise these molecules, we analysed grapevine leaf discs infected with P. viticola with MSI. Plant material preparation was optimised, and different matrices and solvents were tested. Our data shows that trichomes hamper matrix deposition and the ion signal. Results show that putatively identified sucrose presents a higher accumulation and a non-homogeneous distribution in the infected leaf discs in comparison with the controls. This accumulation was mainly on the veins, leading to the hypothesis that sucrose metabolism is being manipulated by the development structures of P. viticola. Up to our knowledge this is the first time that the localisation of a putatively identified sucrose metabolite was shown to be associated to P. viticola infection sites.