307 research outputs found

    Leaf apoplastic proteome composition in UV-B treated Arabidopsis thaliana mutants impaired in extracellular glutathione degradation

    Get PDF
    In plants, environmental perturbations often result in oxidative reactions in the apoplastic space, which are counteracted for by enzymatic and non-enzymatic antioxidative systems, including ascorbate and glutathione. The occurrence of the latter and its exact role in the extracellular space are not well documented, however. In Arabidopsis thaliana, the gamma-glutamyl transferase isoform GGT1 bound to the cell wall takes part in the so-called gamma-glutamyl cycle for extracellular glutathione degradation and recovery, and may be implicated in redox sensing and balance. In this work, oxidative conditions were imposed with UV-B radiation and studied in redox altered ggt1 mutants. Elevated UV-B has detrimental effects on plant metabolism, plasma membranes representing a major target for ROS generated by this harmful radiation. The response of ggt1 knockout Arabidopsis leaves to UV-B radiation was assessed by investigating changes in apoplastic protein composition. We then compared the expression changes resulting from the mutation and from the UV-B treatment. Rearrangements occurring in apoplastic protein composition suggest the involvement of hydrogen peroxide, which may ultimately act as a signal. Other important changes related to hormonal effects, cell wall remodeling, and redox activities are also reported. We argue that oxidative stress conditions imposed by UV-B and by disruption of the gamma-glutamyl cycle result in similar stress-induced responses, to some degree at least. Data shown here are associated with the article from Trentin et al. [1]; protein data have been deposited to the PRIDE database [2] with identifier PXD001807

    From FDI network topology to macroeconomic instability

    Get PDF
    © 2019, Springer-Verlag GmbH Germany, part of Springer Nature. Fragmentation of production undoubtedly constitutes a possible channel of economic contagion and could play a key role in the study of systemic risk. Investments abroad implicitly create long-range economic dependencies between investors and the economies of destination, possibly triggering contagion phenomena. Complex network theory is a primary tool for highlighting economic mutual relationships and paths of contagion, shedding light on intrinsic systemic risks. In this paper, we reconstruct the EU28 foreign direct investments network and study its evolution from 2003 to 2015. Our analysis aims at detecting the changes of topological properties during the crisis, in order to assess how they affected the architecture of economic relationships. Through a detailed study of correlations at different time lags between network measurements and macroeconomic variables, we assess systemic risks. The main findings are: (i) 2009 marks a clear break in network evolution: prior to 2009 the structure was characterized by only one or few hubs/ countries, while in later years a set of connected key nodes emerged; (ii) an increasing heterogeneity is observed in link weights during the entire period analysed (2003–2015); (iii) after 2009, a rewiring of investments is observed towards the EU28 countries that are considered more safe; (iv) time-lagged centrality measures and macroeconomic variables show a clear correlation

    Fragmentation of production: New challenges for big data–a complex network approach

    Get PDF
    © 2019 Journal of Communications. Globalization is one of the most relevant economic phenomena of the last decades. Due to this reason, the economies of different countries are strongly interconnected. This may lead to higher robustness or higher vulnerability of the whole economic system, depending on the economic scenario. Traditional models are unable to represent the complex relationship among firms. This may lead to a misunderstanding of the complex interconnections between countries, underestimating vulnerability of the world economic system. In this framework, a complex network approach, based on graph theory, is a valuable tool to outline the interdependencies of different countries and their impact on the stability of the whole economic system. Nowadays economic Big Data are available on globalization, helping to have a rigorous approach when shading light on these interdependencies. In this paper, the complex network analysis is applied on a particular shade of globalization, namely fragmentation of production

    Dante inattuale. Studi sul testo e sulla fortuna della "Commedia"

    Get PDF
    Letture di canti della "Divina Commedia" e studi su punti controversi del testo, nella prospettiva del contesto storico e culturale del tempo di Dante; seguiti da esempi di commenti "orientati" da un'idea interpretativa attualizzante, e di rapporti peculiari instaurati col poema da tre autori postumi (Michelangelo, Anton Francesco Doni e Shakespeare)

    Protein Profiling of Arabidopsis Roots Treated With Humic Substances: Insights Into the Metabolic and Interactome Networks

    Get PDF
    Background and Aim: Humic substances (HSs) influence the chemical and physical properties of the soil, and are also known to affect plant physiology and nutrient uptake. This study aimed to elucidate plant metabolic pathways and physiological processes influenced by HS activity. Methods: Arabidopsis roots were treated with HS for 8 h. Quantitative mass spectrometry-based proteomics analysis of root proteins was performed using the iTRAQ (Isobaric Tag for Relative and Absolute Quantification) technique. Out of 902 protein families identified and quantified for HS treated vs. untreated roots, 92 proteins had different relative content. Bioinformatic tools such as STRING, KEGG, IIS and Cytoscape were used to interpret the biological function, pathway analysis and visualization of network amongst the identified proteins. Results: From this analysis it was possible to evaluate that all of the identified proteins were functionally classified into several categories, mainly redox homeostasis, response to inorganic substances, energy metabolism, protein synthesis, cell trafficking, and division. Conclusion: In the present study an overview of the metabolic pathways most modified by HS biological activity is provided. Activation of enzymes of the glycolytic pathway and up regulation of ribosomal protein indicated a stimulation in energy metabolism and protein synthesis. Regulation of the enzymes involved in redox homeostasis suggest a pivotal role of reactive oxygen species in the signaling and modulation of HS-induced responses

    N-acetylcysteine serves as substrate of 3-mercaptopyruvate sulfurtransferase and stimulates sulfide metabolism in colon cancer cells

    Get PDF
    Hydrogen sulfide (H2S) is an endogenously produced signaling molecule. The enzymes 3-mercaptopyruvate sulfurtransferase (MST), partly localized in mitochondria, and the inner mitochondrial membrane-associated sulfide:quinone oxidoreductase (SQR), besides being respectively involved in the synthesis and catabolism of H2S, generate sulfane sulfur species such as persulfides and polysulfides, currently recognized as mediating some of the H2S biological effects. Reprogramming of H2S metabolism was reported to support cellular proliferation and energy metabolism in cancer cells. As oxidative stress is a cancer hallmark and N-acetylcysteine (NAC) was recently suggested to act as an antioxidant by increasing intracellular levels of sulfane sulfur species, here we evaluated the effect of prolonged exposure to NAC on the H2S metabolism of SW480 colon cancer cells. Cells exposed to NAC for 24 h displayed increased expression and activity of MST and SQR. Furthermore, NAC was shown to: (i) persist at detectable levels inside the cells exposed to the drug for up to 24 h and (ii) sustain H2S synthesis by human MST more effectively than cysteine, as shown working on the isolated recombinant enzyme. We conclude that prolonged exposure of colon cancer cells to NAC stimulates H2S metabolism and that NAC can serve as a substrate for human MST

    126. Evaluation of Replication Competent and Replication Incompetent Adenovirus-Mediated Toxicity in Human Adrenocortical Cells

    Get PDF
    Objectives: Experimental studies indicate that adenoviruses have a natural tropism for the adrenal gland, thus, the systemic use of adenoviral vectors might be associated with side effects due to adrenal gland infection. In this study, human ACC cells were used to assess the toxicity of replication competent adenovirus type 5 (Ad5) and replication deficient E1-/E3- adenoviral vectors. Methods: To test the susceptibility of human ACC cells (SW13 and NCI-H295R) to adenoviral infection, expression of coxsackie and adenovirus receptor(CAR) and integrins was evaluated in ACC cells as well as in normal human adrenocortical tissues and in benign and malignant adrenocortical tumor samples by quantitative real-time RT-PCR. ACC cells were infected with Ad5 and tested for virus production at different time points pi. Recombinant E1-/E3- Ad5 vector expressing green fluorescent protein (Ad5-EGFP) was used to test adenovirus infectivity by fluorescent microscopy and FACS analysis. To assess the toxicity of replication competent and replication incompetent adenoviral vectors in the adrenal gland, Ad5, Ad5-EGFP and Ad5-HSV-TK were employed. In this regard, at different time points pi, we examined the effect of adenoviral infection on gene expression profile by DNA microarray analysis and on cell growth by proliferation assay, cell cycle analysis, and apoptosis test. The influence of adenoviral infection on steroid hormone production was also analyzed. Results: CAR expression was demonstrated in ACC cells and in normal and neoplastic adrenocortical tissues. Both ACC cells demonstrated productive Ad5 replication and efficient Ad5-EGFP transduction. Time- and dose-dependent induction of cell death was found only in Ad5-infected ACC cells, whereas Ad5- EGFP and Ad5-HSV-TK had no apparent effect on cell proliferation, cell cycle, and cell death as compared to uninfected control. ACC cells did not show marked alterations of gene expression after Ad5-EGFP infection, as demonstrated by microarray analysis in time course infection experiments. In the early phase of infection, genes involved in cell proliferation, stress and innate immune response were transiently upregulated. Moreover, expression of genes encoding steroidogenic enzymes was modulated toward cortisol hypersecretion. With regard to steroidogenesis, ACC cells infected with Ad5 showed decreased basal steroid hormone production in the early phase pi, followed by increased steroid hormone release at 72 h pi. At variance, Ad5-EGFP markedly induced cortisol and estradiol production, but not aldosterone production, at all time points pi. Conclusions: These results, which provide insight into the host response following adenoviral infection of ACC cells, contribute to the understanding of the adrenal involvement during natural adenovirus infection and vector administration for gene therapy

    Proteome readjustments in the apoplastic space of Arabidopsis thaliana ggt1 mutant leaves exposed to UV-B radiation

    Get PDF
    Ultraviolet-B radiation acts as an environmental stimulus, but in high doses it has detrimental effects on plant metabolism. Plasma membranes represent a major target for ROS generated by this harmful radiation. Oxidative reactions occurring in the apoplastic space are counteracted by antioxidative systems mainly involving ascorbate and, to some extent, glutathione. The occurrence of the latter and its exact role in the extracellular space are not well documented, however. In Arabidopsis thaliana, the gamma-glutamyl transferase isoform GGT1 bound to the cell wall takes part in the so-called gamma-glutamyl cycle for extracellular glutathione degradation and recovery, and may be implicated in redox sensing and balance. In this work, oxidative conditions were imposed with UV-B and studied in redox altered ggt1 mutants. The response of ggt1 knockout Arabidopsis leaves to UV-B radiation was assessed by investigating changes in extracellular glutathione and ascorbate content and their redox state, and in apoplastic protein composition. Our results show that, on UV-B exposure, soluble antioxidants respond to the oxidative conditions in both genotypes. Rearrangements occur in their apoplastic protein composition, suggesting an involvement of H2O2, which may ultimately act as a signal. Other important changes relating to hormonal effects, cell wall remodeling, and redox activities are discussed. We argue that oxidative stress conditions imposed by UV-B and disruption of the gamma-glutamyl cycle result in similar stress-induced responses, to some degree at least. Data are available via ProteomeXchange with identifier PXD001807

    Generation of a transgene-free induced pluripotent stem cells line (UNIPDi002-A) from oral mucosa epithelial stem cells carrying the R304Q mutation in TP63 gene.

    Get PDF
    Abstract Transgene free UNIPDi002-A-human induced pluripotent stem cell (hiPSC) line was generated by Sendai Virus Vectors reprogramming from human oral mucosal epithelial stem cells (hOMESCs) of a patient affected by ectrodactyly-ectodermal dysplasia-clefting (EEC)-syndrome, carrying a mutation in exon 8 of the TP63 gene (R304Q). The UNIPDi002-A-hiPSC line retained the mutation of the parental R304Q-hOMESCs and displayed a normal karyotype. No residual expression of transgenes nor Sendai virus vector sequences were detected in the line at passage 8. UNIPDi002-A-hiPSC expressed a panel of pluripotency-associated markers and could form embryoid bodies expressing markers belonging to the three germ layers ectoderm, endoderm and mesoderm

    Induced pluripotent stem cells line (UNIPDi003-A) from a patient affected by EEC syndrome carrying the R279H mutation in TP63 gene.

    Get PDF
    Abstract Oral mucosa epithelial stem cells from a patient affected by Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) syndrome carrying the R279H mutation in the TP63 gene were reprogrammed into human induced pluripotent stem cells (hiPSCs) with episomal vectors. The generated UNIPDi003-A-hPSC line retained the mutation of the parental cells and showed a normal karyotype upon long term culture. Analysis of residual transgenes expression showed that the episomal vectors were eliminated from the cell line. UNIPDi003-A-hiPSCs expressed the undifferentiated state marker alkaline phosphatase along with a panel of pluripotency markers, and formed embryoid bodies capable of expressing markers belonging to all the three germ layers
    • …
    corecore