50 research outputs found
Up the nose of the beholder? Aesthetic perception in olfaction as a decision-making process
Is the sense of smell a source of aesthetic perception? Traditional philosophical aesthetics has centered on vision and audition but eliminated smell for its subjective and inherently affective character. This article dismantles the myth that olfaction is an unsophisticated sense. It makes a case for olfactory aesthetics by integrating recent insights in neuroscience with traditional expertise about flavor and fragrance assessment in perfumery and wine tasting. My analysis concerns the importance of observational refinement in aesthetic experience. I argue that the active engagement with stimulus features in perceptual processing shapes the phenomenological content, so much so that the perceptual structure of trained smelling varies significantly from naive smelling. In a second step, I interpret the processes that determine such perceptual refinement in the context of neural decision-making processes, and I end with a positive outlook on how research in neuroscience can be used to benefit philosophical aesthetics
A COMPASS for VESPUCCI: a FAIR way to explore the grapevine transcriptomic landscape
7openInternational coauthor/editoropenMoretto, M.; Sonego, P.; Pilati, S.; Matus, J.T.; Costantini, L.; Malacarne, G.; Engelen, K.Moretto, M.; Sonego, P.; Pilati, S.; Matus, J.T.; Costantini, L.; Malacarne, G.; Engelen, K
Resistance to Plasmopara viticola in a grapevine segregating population is associated with stilbenoid accumulation and with specific host transcriptional responses
<p>Abstract</p> <p>Background</p> <p>Downy mildew, caused by the oomycete <it>Plasmopara viticola</it>, is a serious disease in <it>Vitis </it><it>vinifera</it>, the most commonly cultivated grapevine species. Several wild <it>Vitis </it>species have instead been found to be resistant to this pathogen and have been used as a source to introgress resistance into a <it>V. vinifera </it>background. Stilbenoids represent the major phytoalexins in grapevine, and their toxicity is closely related to the specific compound. The aim of this study was to assess the resistance response to <it>P. viticola </it>of the Merzling × Teroldego cross by profiling the stilbenoid content of the leaves of an entire population and the transcriptome of resistant and susceptible individuals following infection.</p> <p>Results</p> <p>A three-year analysis of the population's response to artificial inoculation showed that individuals were distributed in nine classes ranging from total resistance to total susceptibility. In addition, quantitative metabolite profiling of stilbenoids in the population, carried out using HPLC-DAD-MS, identified three distinct groups differing according to the concentrations present and the complexity of their profiles. The high producers were characterized by the presence of <it>trans</it>-resveratrol, <it>trans</it>-piceid, <it>trans</it>-pterostilbene and up to thirteen different viniferins, nine of them new in grapevine.</p> <p>Accumulation of these compounds is consistent with a resistant phenotype and suggests that they may contribute to the resistance response.</p> <p>A preliminary transcriptional study using cDNA-AFLP selected a set of genes modulated by the oomycete in a resistant genotype. The expression of this set of genes in resistant and susceptible genotypes of the progeny population was then assessed by comparative microarray analysis.</p> <p>A group of 57 genes was found to be exclusively modulated in the resistant genotype suggesting that they are involved in the grapevine-<it>P. viticola </it>incompatible interaction. Functional annotation of these transcripts revealed that they belong to the categories defense response, photosynthesis, primary and secondary metabolism, signal transduction and transport.</p> <p>Conclusions</p> <p>This study reports the results of a combined metabolic and transcriptional profiling of a grapevine population segregating for resistance to <it>P. viticola</it>. Some resistant individuals were identified and further characterized at the molecular level. These results will be valuable to future grapevine breeding programs.</p
Vitis OneGenE: a causality-based approach to generate gene networks in Vitis vinifera sheds light on the laccase and dirigent gene families
9openInternationalBothThe abundance of transcriptomic data and the development of causal inference methods have paved the way for gene network analyses in grapevine. Vitis OneGenE is a transcriptomic data mining tool that finds direct correlations between genes, thus producing association networks. As a proof of concept, the stilbene synthase gene regulatory network obtained with OneGenE has been compared with published co-expression analysis and experimental data, including cistrome data for MYB stilbenoid regulators. As a case study, the two secondary metabolism pathways of stilbenoids and lignin synthesis were explored. Several isoforms of laccase, peroxidase, and dirigent protein genes, putatively involved in the final oxidative oligomerization steps, were identified as specifically belonging to either one of these pathways. Manual curation of the predicted sequences exploiting the last available genome assembly, and the integration of phylogenetic and OneGenE analyses, identified a group of laccases exclusively present in grapevine and related to stilbenoids. Here we show how network analysis by OneGenE can accelerate knowledge discovery by suggesting new candidates for functional characterization and application in breeding programs.openPilati, Stefania; Malacarne, Giulia; Navarro-Payá, David; Tomè, Gabriele; Riscica, Laura; Cavecchia, Valter; Matus, José Tomás; Moser, Claudio; Blanzieri, EnricoPilati, S.; Malacarne, G.; Navarro-Payá, D.; Tomè, G.; Riscica, L.; Cavecchia, V.; Matus, J.T.; Moser, C.; Blanzieri, E
Wiskott-Aldrich syndrome protein interacts and inhibits diacylglycerol kinase alpha promoting IL-2 induction
Background: Phosphorylation of diacylglycerol by diacylglycerol-kinases represents a major inhibitory event constraining T cell activation upon antigen engagement. Efficient TCR signalling requires the inhibition of the alpha isoform of diacylglycerol kinase, DGKα, by an unidentified signalling pathway triggered by the protein adaptor SAP. We previously demonstrated that, in SAP absence, excessive DGKα activity makes the T cells resistant to restimulation-induced cell death (RICD), an apoptotic program counteracting excessive T cell clonal expansion. Results: Herein, we report that the Wiskott-Aldrich syndrome protein (WASp) inhibits DGKα through a specific interaction of the DGKα recoverin homology domain with the WH1 domain of WASp. Indeed, WASp is necessary and sufficient for DGKα inhibition, and this WASp function is independent of ARP2/3 activity. The adaptor protein NCK-1 and the small G protein CDC42 connect WASp-mediated DGKα inhibition to SAP and the TCR signalosome. In primary human T cells, this new signalling pathway is necessary for a full response in terms of IL-2 production, while minimally affecting TCR signalling and restimulation-induced cell death. Conversely, in T cells made resistant to RICD by SAP silencing, the enhanced DAG signalling due to DGKα inhibition is sufficient to restore apoptosis sensitivity. Conclusion: We discover a novel signalling pathway where, upon strong TCR activation, the complex between WASp and DGKα blocks DGKα activity, allowing a full cytokine response
Grapevine DMR6-1 Is a candidate gene for susceptibility to Downy mildew
Grapevine (Vitis vinifera) is a valuable crop in Europe for both economical and cultural reasons, but highly susceptible to Downy mildew (DM). The generation of resistant vines is of critical importance for a sustainable viticulture and can be achieved either by introgression of resistance genes in susceptible varieties or by mutation of Susceptibility (S) genes, e.g., by gene editing. This second approach offers several advantages: it maintains the genetic identity of cultivars otherwise disrupted by crossing and generally results in a broad-spectrum and durable resistance, but it is hindered by the poor knowledge about S genes in grapevines. Candidate S genes are Downy mildew Resistance 6 (DMR6) and DMR6-Like Oxygenases (DLOs), whose mutations confer resistance to DM in Arabidopsis. In this work, we show that grapevine VviDMR6-1 complements the Arabidopsis dmr6-1 resistant mutant. We studied the expression of grapevine VviDMR6 and VviDLO genes in different organs and in response to the DM causative agent Plasmopara viticola. Through an automated evaluation of causal relationships among genes, we show that VviDMR6-1, VviDMR6-2, and VviDLO1 group into different co-regulatory networks, suggesting distinct functions, and that mostly VviDMR6-1 is connected with pathogenesis-responsive genes. Therefore, VviDMR6-1 represents a good candidate to produce resistant cultivars with a gene-editing approac
Regulation of flavonol content and composition in (Syrah×Pinot Noir) mature grapes: integration of transcriptional profiling and metabolic quantitative trait locus analyses
8openInternationalFlavonols are a ubiquitous class of flavonoids that accumulate preferentially in flowers and mature berries. Besides their photo-protective function, they play a fundamental role during winemaking, stabilizing the colour by co-pigmentation with anthocyanins and contributing to organoleptic characteristics. Although the general flavonol pathway has been genetically and biochemically elucidated, the genetic control of flavonol content and composition at harvest is still not clear. To this purpose, the grapes of 170 segregating F1 individuals from a ‘Syrah’×’Pinot Noir’ population were evaluated at the mature stage for the content of six flavonol aglycons in four seasons. Metabolic data in combination with genetic data enabled the identification of 16 mQTLs (metabolic quantitative trait loci). For the first time, major genetic control by the linkage group 2 (LG 2)/MYBA region on flavonol variation, in particular of tri-hydroxylated flavonols, is demonstrated. Moreover, seven regions specifically associated with the fine control of flavonol biosynthesis are identified. Gene expression profiling of two groups of individuals significantly divergent for their skin flavonol content identified a large set of differentially modulated transcripts. Among these, the transcripts coding for MYB and bZIP transcription factors, methyltranferases, and glucosyltranferases specific for flavonols, proteins, and factors belonging to the UV-B signalling pathway and co-localizing with the QTL regions are proposed as candidate genes for the fine regulation of flavonol content and composition in mature grapesopenMalacarne, G.; Costantini, L.; Coller, E.; Battilana, J.; Velasco, R.; Vrhovsek, U.; Grando, M.S.; Moser, C.Malacarne, G.; Costantini, L.; Coller, E.; Battilana, J.; Velasco, R.; Vrhovsek, U.; Grando, M.S.; Moser, C
Grapevine DMR6-1 Is a Candidate Gene for Susceptibility to Downy mildew
Grapevine (Vitis vinifera) is a valuable crop in Europe for both economical and cultural reasons, but highly susceptible to Downy mildew (DM). The generation of resistant vines is of critical importance for a sustainable viticulture and can be achieved either by introgression of resistance genes in susceptible varieties or by mutation of Susceptibility (S) genes, e.g., by gene editing. This second approach offers several advantages: it maintains the genetic identity of cultivars otherwise disrupted by crossing and generally results in a broad-spectrum and durable resistance, but it is hindered by the poor knowledge about S genes in grapevines. Candidate S genes are Downy mildew Resistance 6 (DMR6) and DMR6-Like Oxygenases (DLOs), whose mutations confer resistance to DM in Arabidopsis. In this work, we show that grapevine VviDMR6-1 complements the Arabidopsis dmr6-1 resistant mutant. We studied the expression of grapevine VviDMR6 and VviDLO genes in different organs and in response to the DM causative agent Plasmopara viticola. Through an automated evaluation of causal relationships among genes, we show that VviDMR6-1, VviDMR6-2, and VviDLO1 group into different co-regulatory networks, suggesting distinct functions, and that mostly VviDMR6-1 is connected with pathogenesis-responsive genes. Therefore, VviDMR6-1 represents a good candidate to produce resistant cultivars with a gene-editing approach
Wiskott-Aldrich syndrome protein interacts and inhibits diacylglycerol kinase alpha promoting IL-2 induction
BackgroundPhosphorylation of diacylglycerol by diacylglycerol-kinases represents a major inhibitory event constraining T cell activation upon antigen engagement. Efficient TCR signalling requires the inhibition of the alpha isoform of diacylglycerol kinase, DGKα, by an unidentified signalling pathway triggered by the protein adaptor SAP. We previously demonstrated that, in SAP absence, excessive DGKα activity makes the T cells resistant to restimulation-induced cell death (RICD), an apoptotic program counteracting excessive T cell clonal expansion.ResultsHerein, we report that the Wiskott-Aldrich syndrome protein (WASp) inhibits DGKα through a specific interaction of the DGKα recoverin homology domain with the WH1 domain of WASp. Indeed, WASp is necessary and sufficient for DGKα inhibition, and this WASp function is independent of ARP2/3 activity. The adaptor protein NCK-1 and the small G protein CDC42 connect WASp-mediated DGKα inhibition to SAP and the TCR signalosome. In primary human T cells, this new signalling pathway is necessary for a full response in terms of IL-2 production, while minimally affecting TCR signalling and restimulation-induced cell death. Conversely, in T cells made resistant to RICD by SAP silencing, the enhanced DAG signalling due to DGKα inhibition is sufficient to restore apoptosis sensitivity.ConclusionWe discover a novel signalling pathway where, upon strong TCR activation, the complex between WASp and DGKα blocks DGKα activity, allowing a full cytokine response