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1.
Elife ; 122023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37526647

RESUMO

Plant secondary metabolites that are released into the rhizosphere alter biotic and abiotic soil properties, which in turn affect the performance of other plants. How this type of plant-soil feedback affects agricultural productivity and food quality in the field in the context of crop rotations is unknown. Here, we assessed the performance, yield and food quality of three winter wheat varieties growing in field plots whose soils had been conditioned by either wild type or benzoxazinoid-deficient bx1 maize mutant plants. Following maize cultivation, we detected benzoxazinoid-dependent chemical and microbial fingerprints in the soil. The benzoxazinoid fingerprint was still visible during wheat growth, but the microbial fingerprint was no longer detected. Wheat emergence, tillering, growth, and biomass increased in wild type conditioned soils compared to bx1 mutant conditioned soils. Weed cover was similar between soil conditioning treatments, but insect herbivore abundance decreased in benzoxazinoid-conditioned soils. Wheat yield was increased by over 4% without a reduction in grain quality in benzoxazinoid-conditioned soils. This improvement was directly associated with increased germination and tillering. Taken together, our experiments provide evidence that soil conditioning by plant secondary metabolite producing plants can increase yield via plant-soil feedbacks under agronomically realistic conditions. If this phenomenon holds true across different soils and environments, optimizing root exudation chemistry could be a powerful, genetically tractable strategy to enhance crop yields without additional inputs.


Assuntos
Benzoxazinas , Solo , Solo/química , Retroalimentação , Benzoxazinas/metabolismo , Agricultura , Zea mays/metabolismo , Grão Comestível/metabolismo , Triticum
2.
Environ Microbiol ; 24(12): 6376-6391, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35837848

RESUMO

Burgundy truffles are heterothallic ascomycetes that grow in symbiosis with trees. Despite their esteemed belowground fruitbodies, the species' complex lifecycle is still not fully understood. Here, we present the genetic patterns in three natural Burgundy truffle populations based on genotyped fruitbodies, ascospore extracts and ectomycorrhizal root tips using microsatellites and the mating-type locus. Distinct genetic structures with high relatedness in close vicinity were found for females (forming the fruitbodies) and males (fertilizing partner as inferred from ascospore extracts), with high genotypic diversity and annual turnover of males, suggesting that ephemeral male mating partners are germinating ascospores from decaying fruitbodies. The presence of hermaphrodites and the interannual persistence of a few males suggest that persistent mycelia may sporadically also act as males. Only female or hermaphroditic individuals were detected on root tips. At one site, fruitbodies grew in a fairy ring formed by a large female individual that showed an outward growth rate of 30 cm per year, with the mycelium decaying within the ring and being fertilized by over 50 male individuals. While fairy ring structures have never been shown for truffles, the genetics of Burgundy truffle populations support a similar reproductive biology as those of other highly prized truffles.


Assuntos
Ascomicetos , Micorrizas , Humanos , Masculino , Animais , Ascomicetos/genética , Micorrizas/genética , Simbiose , Estágios do Ciclo de Vida
3.
Nat Commun ; 11(1): 5125, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046698

RESUMO

Mycorrhizal fungi are mutualists that play crucial roles in nutrient acquisition in terrestrial ecosystems. Mycorrhizal symbioses arose repeatedly across multiple lineages of Mucoromycotina, Ascomycota, and Basidiomycota. Considerable variation exists in the capacity of mycorrhizal fungi to acquire carbon from soil organic matter. Here, we present a combined analysis of 135 fungal genomes from 73 saprotrophic, endophytic and pathogenic species, and 62 mycorrhizal species, including 29 new mycorrhizal genomes. This study samples ecologically dominant fungal guilds for which there were previously no symbiotic genomes available, including ectomycorrhizal Russulales, Thelephorales and Cantharellales. Our analyses show that transitions from saprotrophy to symbiosis involve (1) widespread losses of degrading enzymes acting on lignin and cellulose, (2) co-option of genes present in saprotrophic ancestors to fulfill new symbiotic functions, (3) diversification of novel, lineage-specific symbiosis-induced genes, (4) proliferation of transposable elements and (5) divergent genetic innovations underlying the convergent origins of the ectomycorrhizal guild.


Assuntos
Fungos/genética , Genoma Fúngico , Micorrizas/genética , Simbiose , Ecossistema , Evolução Molecular , Proteínas Fúngicas/genética , Fungos/classificação , Fungos/fisiologia , Micorrizas/classificação , Micorrizas/fisiologia , Filogenia , Fenômenos Fisiológicos Vegetais , Plantas/microbiologia
4.
Front Oncol ; 10: 1218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850359

RESUMO

Background: Glycosylation is one of the most fundamental post-translational modifications. Importantly, glycosylation is altered in many cancers. These alterations have been proven to impact on tumor progression and to promote tumor cell survival. From the literature, it is known that there is a clear link between chemoresistance and hypoxia, hypoxia and epigenetics and more recently glycosylation and epigenetics. Methods and Results: Our objective was to investigate these differential parameters, in an in vitro model of ovarian and breast cancer. Ovarian (A2780, A2780cis, PEO1, PEO4) and triple negative breast cancer (TNBC) (MDA-MB-231 and MDA-MB-436) cells were exposed to differential hypoxic conditions (0.5-2% O2) and compared to normoxia (21% O2). Results demonstrated that in hypoxic conditions some significant changes in glycosylation on the secreted N-glycans from the ovarian and breast cancer cell lines were observed. These included, alterations in oligomannosylated, bisected glycans, glycans with polylactosamine extensions, in branching, galactosylation and sialylation in all cell lines except for PEO1. In general, hypoxia exposed ovarian and TNBC cells also displayed increased epithelial to mesenchymal transition (EMT) and migration, with a greater effect seen in the 0.5% hypoxia exposed samples compared to 1 and 2% hypoxia (p ≤ 0.05). SiRNA transient knock down of GATA2/3 transcription factors resulted in a decrease in the expression of glycosyltransferases ST3GAL4 and MGAT5, which are responsible for sialylation and branching, respectively. Conclusions: These glycan changes are known to be integral to cancer cell survival and metastases, suggesting a possible mechanism of action, linking GATA2 and 3, and invasiveness of both ovarian and TNBC cells in vitro.

5.
Front Microbiol ; 9: 141, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29487573

RESUMO

Cenococcum geophilum is an ectomycorrhizal fungus with global distribution in numerous habitats and associates with a large range of host species including gymnosperm and angiosperm trees. Moreover, C. geophilum is the unique ectomycorrhizal species within the clade Dothideomycetes, the largest class of Ascomycetes containing predominantly saprotrophic and many devastating phytopathogenic fungi. Recent studies highlight that mycorrhizal fungi, as pathogenic ones, use effectors in form of Small Secreted Proteins (SSPs) as molecular keys to promote symbiosis. In order to better understand the biotic interaction of C. geophilum with its host plants, the goal of this work was to characterize mycorrhiza-induced small-secreted proteins (MiSSPs) that potentially play a role in the ectomycorrhiza formation and functioning of this ecologically very important species. We combined different approaches such as gene expression profiling, genome localization and conservation of MiSSP genes in different C. geophilum strains and closely related species as well as protein subcellular localization studies of potential targets of MiSSPs in interacting plants using in tobacco leaf cells. Gene expression analyses of C. geophilum interacting with Pinus sylvestris (pine) and Populus tremula × Populus alba (poplar) showed that similar sets of genes coding for secreted proteins were up-regulated and only few were specific to each host. Whereas pine induced more carbohydrate active enzymes (CAZymes), the interaction with poplar induced the expression of specific SSPs. We identified a set of 22 MiSSPs, which are located in both, gene-rich, repeat-poor or gene-sparse, repeat-rich regions of the C. geophilum genome, a genome showing a bipartite architecture as seen for some pathogens but not yet for an ectomycorrhizal fungus. Genome re-sequencing data of 15 C. geophilum strains and two close relatives Glonium stellatum and Lepidopterella palustris were used to study sequence conservation of MiSSP-encoding genes. The 22 MiSSPs showed a high presence-absence polymorphism among the studied C. geophilum strains suggesting an evolution through gene gain/gene loss. Finally, we showed that six CgMiSSPs target four distinct sub-cellular compartments such as endoplasmic reticulum, plasma membrane, cytosol and tonoplast. Overall, this work presents a comprehensive analysis of secreted proteins and MiSSPs in different genetic level of C. geophilum opening a valuable resource to future functional analysis.

6.
Int J Neuropsychopharmacol ; 21(5): 433-441, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29415258

RESUMO

Background: Brexpiprazole is a serotonin-dopamine activity modulator with efficacy in acute schizophrenia and relapse prevention. The aim of this Phase 3, multicenter study was to assess the long-term safety, tolerability, and efficacy of treatment with brexpiprazole flexible-dose 1-4 mg/d. Methods: Patients rolled over into this 52-week open-label study (amended to 26 weeks towards the end) from 3 randomized, double-blind, placebo-controlled Phase 3 studies. De novo patients, not part of the previous studies, were also enrolled. The primary outcome variable was the frequency and severity of treatment-emergent adverse events. Efficacy was assessed as a secondary objective using the Positive and Negative Syndrome Scale and the Personal and Social Performance scale. Results: A total of 1072 patients was enrolled (952 for 52 weeks and 120 for 26 weeks), 47.4% of whom completed the study. Among patients who took at least one dose of brexpiprazole, 14.6% discontinued due to treatment-emergent adverse events, most commonly schizophrenia (8.8%) and psychotic disorder (1.5%). Treatment-emergent adverse events with an incidence of ≥5% were schizophrenia (11.6%), insomnia (8.6%), weight increased (7.8%), headache (6.4%), and agitation (5.4%). Most treatment-emergent adverse events were mild or moderate in severity. The mean increase in body weight from baseline to week 26 was 1.3 kg and to week 52 was 2.1 kg. There were no clinically relevant findings related to prolactin, lipids, and glucose, or QT prolongation. On average, patients' symptoms and functioning showed continual improvement. Conclusions: Treatment with brexpiprazole 1-4 mg/d was generally well tolerated for up to 52 weeks in patients with schizophrenia. ClinicalTrials.gov identifier: NCT01397786 (https://clinicaltrials.gov/show/NCT01397786).


Assuntos
Antipsicóticos/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Quinolonas/farmacologia , Esquizofrenia/tratamento farmacológico , Prevenção Secundária , Tiofenos/farmacologia , Adulto , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quinolonas/administração & dosagem , Quinolonas/efeitos adversos , Tiofenos/administração & dosagem , Tiofenos/efeitos adversos
7.
Int J Neuropsychopharmacol ; 20(1): 11-21, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27566723

RESUMO

Background: Brexpiprazole has previously demonstrated efficacy in acute schizophrenia trials. The objective of this trial was to assess the efficacy, safety, and tolerability of maintenance treatment with brexpiprazole in adults with schizophrenia. Methods: Patients with an acute exacerbation of psychotic symptoms were converted to brexpiprazole (1-4mg/d) over 1 to 4 weeks and entered a single-blind stabilization phase. Those patients who met stability criteria for 12 weeks were randomized 1:1 to double-blind maintenance treatment with either brexpiprazole (at their stabilization dose) or placebo for up to 52 weeks. The primary efficacy endpoint was the time from randomization to impending relapse. Safety and tolerability were also assessed. Results: A total of 524 patients were enrolled, 202 of whom were stabilized on brexpiprazole and randomized to brexpiprazole (n=97) or placebo (n=105). Efficacy was demonstrated at a prespecified interim analysis (conducted after 45 events), and so the trial was terminated early. The final analysis showed that time to impending relapse was statistically significantly delayed with brexpiprazole treatment compared with placebo (P<.0001, log-rank test). The hazard ratio for the final analysis was 0.292 (95% confidence interval: 0.156, 0.548); mean dose at last visit, 3.6mg. The proportion of patients meeting the criteria for impending relapse was 13.5% with brexpiprazole and 38.5% with placebo (P<.0001). During the maintenance phase, the incidence of adverse events was comparable to placebo. Conclusions: or patients with schizophrenia already stabilized on brexpiprazole, maintenance treatment with brexpiprazole was efficacious, with a favorable safety profile.


Assuntos
Antipsicóticos/uso terapêutico , Quinolonas/uso terapêutico , Esquizofrenia/tratamento farmacológico , Tiofenos/uso terapêutico , Adolescente , Adulto , Idoso , Antipsicóticos/efeitos adversos , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Escalas de Graduação Psiquiátrica , Quinolonas/efeitos adversos , Recidiva , Tiofenos/efeitos adversos , Resultado do Tratamento , Adulto Jovem
8.
Am J Psychiatry ; 172(9): 870-80, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25882325

RESUMO

OBJECTIVE: The efficacy, safety, and tolerability of brexpiprazole and placebo were compared in adults with acute schizophrenia. METHOD: This was a multicenter, randomized, double-blind, placebo-controlled study. Patients with schizophrenia experiencing an acute exacerbation were randomly assigned to daily brexpiprazole at a dosage of 0.25, 2, or 4 mg or placebo (1:2:2:2) for 6 weeks. Outcomes included change from baseline to week 6 in Positive and Negative Syndrome Scale (PANSS) total score (primary endpoint measure), Clinical Global Impressions Scale (CGI) severity score (key secondary endpoint measure), and other efficacy and tolerability measures. RESULTS: The baseline overall mean PANSS total score was 95.2, and the CGI severity score was 4.9. Study completion rates were 62.2%, 68.1%, and 67.2% for patients in the 0.25-, 2-, and 4-mg brexpiprazole groups, respectively, versus 59.2% in the placebo group. At week 6, compared with placebo, brexpiprazole dosages of 2 and 4 mg produced statistically significantly greater reductions in PANSS total score (treatment differences: -8.72 and -7.64, respectively) and CGI severity score (treatment differences: -0.33 and -0.38). The most common treatment-emergent adverse event for brexpiprazole was akathisia (2 mg: 4.4%; 4 mg: 7.2%; placebo: 2.2%). Weight gain with brexpiprazole was moderate (1.45 and 1.28 kg for 2 and 4 mg, respectively, versus 0.42 kg for placebo at week 6). There were no clinically or statistically significant changes from baseline in lipid and glucose levels and extrapyramidal symptom ratings. CONCLUSIONS: Brexpiprazole at dosages of 2 and 4 mg/day demonstrated statistically significant efficacy compared with placebo and good tolerability for patients with an acute schizophrenia exacerbation.


Assuntos
Antipsicóticos/uso terapêutico , Quinolonas/uso terapêutico , Esquizofrenia/tratamento farmacológico , Tiofenos/uso terapêutico , Doença Aguda , Adulto , Acatisia Induzida por Medicamentos/etiologia , Antipsicóticos/administração & dosagem , Glicemia/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Lipídeos/sangue , Masculino , Escalas de Graduação Psiquiátrica , Quinolonas/efeitos adversos , Tiofenos/efeitos adversos , Resultado do Tratamento , Aumento de Peso/efeitos dos fármacos
9.
Schizophr Res ; 164(1-3): 127-35, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25682550

RESUMO

The objective of this study was to evaluate the efficacy, safety and tolerability of brexpiprazole versus placebo in adults with acute schizophrenia. This was a 6-week, multicenter, placebo-controlled double-blind phase 3 study. Patients with acute schizophrenia were randomized to brexpiprazole 1, 2 or 4 mg, or placebo (2:3:3:3) once daily. The primary endpoint was changed from baseline at week 6 in Positive and Negative Syndrome Scale (PANSS) total score; the key secondary endpoint was Clinical Global Impressions-Severity (CGI-S) at week 6. Brexpiprazole 4 mg showed statistically significant improvement versus placebo (treatment difference: -6.47, p=0.0022) for the primary endpoint. Improvement compared with placebo was also seen for the key secondary endpoint (treatment difference: -0.38, p=0.0015), and on multiple secondary efficacy outcomes. Brexpiprazole 1 and 2mg also showed numerical improvements versus placebo, although p>0.05. The most common treatment-emergent adverse events were headache, insomnia and agitation; incidences of akathisia were lower in the brexpiprazole treatment groups (4.2%-6.5%) versus placebo (7.1%). Brexpiprazole treatment was associated with moderate weight gain at week 6 (1.23-1.89 kg versus 0.35 kg for placebo); there were no clinically relevant changes in laboratory parameters and vital signs. In conclusion, brexpiprazole 4 mg is an efficacious and well-tolerated treatment for acute schizophrenia in adults. Clinical Trials.gov NCT01393613; BEACON trial.


Assuntos
Quinolonas/uso terapêutico , Esquizofrenia/tratamento farmacológico , Serotoninérgicos/uso terapêutico , Tiofenos/uso terapêutico , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Resultado do Tratamento , Adulto Jovem
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