497 research outputs found

    Comparative analyses of three grapevine Pinot gris virus cDNA clones reveal insights into the pathological properties of different phylogroups

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    Grapevine Pinot gris virus (GPGV) is an emerging grapevine virus associated with grapevine leaf mottling and deformation (GLMD) disease. Being a recently identified virus, the molecular biology, pathological properties, and etiological complexity of GPGV remain poorly studied. Previous research revealed that GPGV comprises genetically different variants, some encoding a larger movement protein (MP) and others a shorter MP due to a C/T polymorphic site in ORF2 encoding MP. Variants that encode the shorter MP are associated with severe disease, whereas variants encoding the longer MP are associated with mild or no symptoms. However, this has yet to be demonstrated experimentally. Here, we report the construction of a wildtype cDNA clone, pGPGV-SY, based on ON93-12, a local isolate from Syrah closely related to the variants encoding the larger MP. Surprisingly, our clone exhibited significantly faster replication and caused more severe disease symptoms than pRI::GPGV-lat, an Italian GPGV clone, with a longer MP and demonstrated similar efficacies with that of pRI::GPGV-vir, another Italian clone with a shorter MP. A single C to T mutation at the polymorphic site of pGPGV-SY resulted in a two-fold higher RNA accumulation in the grapevine. Findings from this work constitute a leap toward the long-standing and complex question pertaining to the relationship between GPGV variant groups and GLMD. Integrating findings from this work and those by others, we propose an updated model to explain the complex relationship between GPGV variants and GLMD

    Language-Related Skills in Bilingual Children With Specific Learning Disorders

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    Purpose: The purpose of this study is to better understand the characteristics of the language-related skills of bilingual children with specific learning disorders (SLD). The aim is achieved by analyzing language-related skills in a sample of bilingual (Italian plus another language) and Italian monolingual children, with and without SLD. Patients and methods: A total of 72 minors aged between 9 and 11 were recruited and divided into four groups: 18 Italian monolingual children with SLD, 18 bilingual children with SLD, 18 Italian monolingual children without SLD, and 18 bilingual children without SLD. Each child underwent tests to evaluate different aspects of language skills: lexical and grammar, metalanguage and executive functions. Results: With regard to lexical and grammatical skills, the conditions of SLD and bilingualism both impact naming in terms of total number of errors for words with low frequency of use, while the condition of SLD has an effect on semantic errors for words with low frequency of use. The condition of bilingualism impacts on the total errors for words with high frequency of use and on circumlocution-type errors for words with low frequency of use. There were significant effects of bilingualism and SLD on the metalinguistic test for understanding implicit meaning, and an impact of SLD on phonological awareness was also found. Conclusion: The results suggest that both SLD and bilingualism have an effect on some lexical skills, in particular for words with low frequency of use. Both conditions, bilingualism and SLD, seem to impact on metalinguistic abilities that depend on lexical knowledge. These findings reinforce the importance of improving understanding of the neuropsychological profile of bilingual children with SLD

    Are Defense Styles Mediators between traumatic Experiences and Maladaptive Daydreaming?

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    Maladaptive daydreaming (MD) is a new proposed mental disorder in which an excessive absorption in vivid, narrative fantasies generates impairments in various life domains. This study aimed to examine the role of traumatic life experiences and immature, neurotic, and mature defense styles in MD. Three hundred and fifty-six Italian adults, ranging in age from 18 to 60 years completed an online survey, including measures of MD, traumatic life events, and defense styles. A multiple mediation model showed that immature, neurotic, and mature defense styles fully mediated the relationship between traumatic life experiences and MD. These findings suggest that clinical interventions for people with a history of traumatic experience who developed MD should aim to help them acquire more adaptive coping strategies to deal with traumatic memories

    'Candidatus Phytoplasma solani' interferes with the distribution and uptake of iron in tomato

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    Background: \u2018Candidatus Phytoplasma solani\u2019 is endemic in Europe and infects a wide range of weeds and cultivated plants. Phytoplasmas are prokaryotic plant pathogens that colonize the sieve elements of their host plant, causing severe alterations in phloem function and impairment of assimilate translocation. Typical symptoms of infected plants include yellowing of leaves or shoots, leaf curling, and general stunting, but the molecular mechanisms underlying most of the reported changes remain largely enigmatic. To infer a possible involvement of Fe in the host-phytoplasma interaction, we investigated the effects of \u2018Candidatus Phytoplasma solani\u2019 infection on tomato plants (Solanum lycopersicum cv. Micro-Tom) grown under different Fe regimes. Results: Both phytoplasma infection and Fe starvation led to the development of chlorotic leaves and altered thylakoid organization. In infected plants, Fe accumulated in phloem tissue, altering the local distribution of Fe. In infected plants, Fe starvation had additive effects on chlorophyll content and leaf chlorosis, suggesting that the two conditions affected the phenotypic readout via separate routes. To gain insights into the transcriptional response to phytoplasma infection, or Fe deficiency, transcriptome profiling was performed on midrib-enriched leaves. RNA-seq analysis revealed that both stress conditions altered the expression of a large (> 800) subset of common genes involved in photosynthetic light reactions, porphyrin / chlorophyll metabolism, and in flowering control. In Fe-deficient plants, phytoplasma infection perturbed the Fe deficiency response in roots, possibly by interference with the synthesis or transport of a promotive signal transmitted from the leaves to the roots. Conclusions: \u2018Candidatus Phytoplasma solani\u2019 infection changes the Fe distribution in tomato leaves, affects the photosynthetic machinery and perturbs the orchestration of root-mediated transport processes by compromising shoot-to-root communication

    SEOR2 in Arabidopsis mediates Ca2+ dependent defense against phytoplasmas and reduction of plant growth

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    The Arabidopsis seor1ko line, which expresses the protein AtSEOR2 free of its bond with AtSEOR1, exhibits a lower phytoplasma titre as compared to wild type plants. In search for mechanism(s) underlying potential SEOR2-mediated defense responses the transcriptome of healthy wild type and Atseor1ko plants was disclosed by RNA sequencing. Comparative transcriptome analysis revealed 1036 differentially expressed genes (DEGs, 893 up- and 143 down-regulated) between the Atseor1ko line and the wild type. Sequence annotation and classification of the up-regulated genes identified “plant-pathogen interaction” among the most enriched clusters. The “plant-pathogen interaction” cluster included genes encoding members of the protein kinase superfamily, actors in calcium/calmodulin signaling transduction and WRKY transcription factors. An interaction network analysis and a host-phytoplasma interaction map demonstrated that AtSEOR2 protein could interact with the calcium-binding proteins CAM2 and TCH3. The latter one also turned out to be an indirect target of the SAP54CY phytoplasma effector, which suggests a SEOR2-mediated role of TCH3 in balancing nutrient investments in plant defense and plant growth

    From Parental Bonding to Problematic Gaming: The Mediating Role of Adult Attachment Styles

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    Background: Research has found that parental failures of care during childhood and insecure attachment styles are positively associated with problematic gaming. From a developmental framework, it is possible to hypothesize that attachment styles mediate the relationship between parental bonding and problematic gaming. Methods: This hypothesis was tested in a sample of 598 videogame players (410 males, 68.56%) aged between 18 and 61 years old (M = 26.68, SD = 7.23). Participants were recruited through an online survey. Self-report instruments were administered to assess problematic gaming, parental bonding, and adult attachment styles. Results: Positive paternal care was a direct and negative predictor of problematic gaming, whereas maternal overprotection indirectly predicted problematic gaming through preoccupied attachment. Conclusions: These findings suggest that positive paternal care represents a protective factor for problematic gaming; in contrast, maternal overprotection might foster a negative view of the self in the child, which increases the risk to excessively use videogames, perhaps as a maladaptive coping strategy to regulate negative feelings. Prevention programs might be aimed to improve the responsiveness of parents towards the child’s emotional needs, to prevent the development of problematic gaming. Also, clinical intervention with problematic gamers might foster their feelings of security toward relationships, to promote both a healthier use of videogames and a better quality of life

    The sieve-element endoplasmic reticulum: A focal point of phytoplasma-host plant interaction?

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    The rough endoplasmic reticulum (r-ER) is of paramount importance for adaptive responses to biotic stresses due to an increased demand for de novo synthesis of immunity-related proteins and signaling components. In nucleate cells, disturbance of r-ER integrity and functionality leads to the “unfolded protein response” (UPR), which is an important component of innate plant immune signalling. In contrast to an abundance of reports on r-ER responses to biotic challenges, sieve-element endoplasmic reticulum (SE-ER) responses to phytoplasma infection have not been investigated. We found that morphological SE-ER changes, associated with phytoplasma infection, are accompanied by differential expression of genes encoding proteins involved in shaping and anchoring the reticulum. Phytoplasma infection also triggers an increased release of bZIP signals from the (SE-ER)/r-ER and consequent differential expression of UPR-related genes. The modified expression patterns seem to reflect a trade-off between survival of host cells, needed for the phytoplasmic biotrophic lifestyle, and phytoplasmas. Specialized plasmodesmata between sieve element and companion cell may provide a corridor for transfer of phytoplasma effectors inducing UPR-related gene expression in companion cells

    Studies on the aetiology of kiwifruit decline: interaction between soil-borne pathogens and waterlogging

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    Aims: In 2012, Italian kiwifruit orchards were hit by a serious root disease of unknown aetiology (kiwifruit decline, KD) that still causes extensive damage to the sector. While waterlogging was soon observed to be associated with its outbreak, the putative role of soil microbiota remains unknown. This work investigates the role of these two factors in the onset of the disease. Methods: Historical rainfall data were analysed to identify changes that might explain KD outbreak and mimic the flooding conditions required to reproduce the disease in a controlled environment. A greenhouse experiment was thus designed, and vines were grown in either unsterilized (U) or sterilized (S) soil collected from KD-affected orchards, and subjected (F) or not (N) to artificial flooding. Treatments were compared in terms of mortality rate, growth, and tissue modifications. Results: KD symptoms were only displayed by FU-treated vines, with an incidence of 90%. Ultrastructural observations detected tyloses and fibrils in the xylem vessels of all plants, irrespective of the treatment. Phytopythium vexans and Phytopythium chamaehyphon, isolated from roots of FU plants, emerged as the associated microorganisms. Conclusions: We succeeded in reproducing KD under controlled conditions and confirmed its association with both waterlogging and soil-borne microorganism(s)
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