The dual nature of trehalose in citrus canker disease: A virulence factor for Xanthomonas citri subsp. citri and a trigger for plant defence responses

Xanthomonas citri subsp. citri (Xcc) is a bacterial pathogen that causes citrus canker in susceptible Citrus spp. The Xcc genome contains genes encoding enzymes from three separate pathways of trehalose biosynthesis. Expression of genes encoding trehalose-6-phosphate synthase (otsA) and trehalose phosphatase (otsB) was highly induced during canker development, suggesting that the two-step pathway of trehalose biosynthesis via trehalose-6-phosphate has a function in pathogenesis. This pathway was eliminated from the bacterium by deletion of the otsA gene. The resulting XccΔotsA mutant produced less trehalose than the wild-type strain, was less resistant to salt and oxidative stresses, and was less able to colonize plant tissues. Gene expression and proteomic analyses of infected leaves showed that infection with XccΔotsA triggered only weak defence responses in the plant compared with infection with Xcc, and had less impact on the host plant's metabolism than the wild-type strain. These results suggested that trehalose of bacterial origin, synthesized via the otsA-otsB pathway, in Xcc, plays a role in modifying the host plant's metabolism to its own advantage but is also perceived by the plant as a sign of pathogen attack. Thus, trehalose biosynthesis has both positive and negative consequences for Xcc. On the one hand, it enables this bacterial pathogen to survive in the inhospitable environment of the leaf surface before infection and exploit the host plant's resources after infection, but on the other hand, it is a tell-tale sign of the pathogen's presence that triggers the plant to defend itself against infection.Fil: Piazza, Ainelén Melanie. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Zimaro, Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Garavaglia, Betiana Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Ficarra, Florencia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Thomas, Ludivine. King Abdullah University of Science and Technology; Arabia SauditaFil: Marondedze, Claudius. King Abdullah University of Science and Technology; Arabia SauditaFil: Feil, Regina. Max Planck Institute of Molecular Plant Physiology; AlemaniaFil: Lunn, John E.. Max Planck Institute of Molecular Plant Physiology; AlemaniaFil: Gehring, Chris. King Abdullah University of Science and Technology; Arabia SauditaFil: Ottado, Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Gottig Schor, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin

DISCURSO PUBLICITÁRIO E IDENTIDADE REGIONAL: UM OLHAR PARA AS MARCAS DE GAUCHIDADE NA PEÇA PEPSITCHÊ

Há um crescente interesse pela cultura e identidade regional local nos textos publicitários. Assim, este artigo tem como objetivo verificar de que forma a expressão “tchê” reitera a identidade do possível consumidor da marca Pepsi, considerando as práticas sociais e discursivas. Além disso, pretende demonstrar que as escolhas lexicais propiciam uma imagem do produto próxima à imagem do possível consumidor. A análise foi construída a partir da peça publicitária “PepsiTchê” e utilizou como abordagem a pesquisa de natureza bibliográfica. Para desenvolver a investigação foi realizado um levantamento através do hotsite dedicado à publicidade da “PepsiTchê”, material de cunho publicitário exclusivo para consumidores gaúchos. Essa metodologia articula contribuições advindas dos conceitos de gênero do discurso, acento de valor, intertextualidade e dialogismo, a partir dos estudos do Círculo de Bakhtin. Como resultados da pesquisa compreendemos que as escolhas dos elementos linguísticos, no gênero discurso publicitário, contribuem com as relações dialógicas estabelecidas entre a marca e o possível consumidor e delimitam os acentos valorativos sobre a marca/produto

The type III protein secretion system contributes to Xanthomonas citri subsp. citri biofilm formation

Background: Several bacterial plant pathogens colonize their hosts through the secretion of effector proteins by a Type III protein secretion system (T3SS). The role of T3SS in bacterial pathogenesis is well established but whether this system is involved in multicellular processes, such as bacterial biofilm formation has not been elucidated. Here, the phytopathogen Xanthomonas citri subsp. citri (X. citri) was used as a model to gain further insights about the role of the T3SS in biofilm formation. Results: The capacity of biofilm formation of different X. citri T3SS mutants was compared to the wild type strain and it was observed that this secretion system was necessary for this process. Moreover, the T3SS mutants adhered proficiently to leaf surfaces but were impaired in leaf-associated growth. A proteomic study of biofilm cells showed that the lack of the T3SS causes changes in the expression of proteins involved in metabolic processes, energy generation, exopolysaccharide (EPS) production and bacterial motility as well as outer membrane proteins. Furthermore, EPS production and bacterial motility were also altered in the T3SS mutants. Conclusions: Our results indicate a novel role for T3SS in X. citri in the modulation of biofilm formation. Since this process increases X. citri virulence, this study reveals new functions of T3SS in pathogenesis.Fil: Zimaro, Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Thomas, Ludivine. King Abdullah University Of Science And Technology;Fil: Marondedze, Claudius. King Abdullah University Of Science And Technology;Fil: Sgro, Germán Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Garofalo, Cecilia Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Ficarra, Florencia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Gehring, Chris. King Abdullah University Of Science And Technology;Fil: Ottado, Jorgelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Gottig Schor, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentin

Alternative splicing of MALT1 controls signalling and activation of CD4+ T cells

MALT1 channels proximal T-cell receptor (TCR) signalling to downstream signalling pathways. With MALT1A and MALT1B two conserved splice variants exist and we demonstrate here that MALT1 alternative splicing supports optimal T-cell activation. Inclusion of exon7 in MALT1A facilitates the recruitment of TRAF6, which augments MALT1 scaffolding function, but not protease activity. Naive CD4+ T cells express almost exclusively MALT1B and MALT1A expression is induced by TCR stimulation. We identify hnRNP U as a suppressor of exon7 inclusion. Whereas selective depletion of MALT1A impairs T-cell signalling and activation, downregulation of hnRNP U enhances MALT1A expression and T-cell activation. Thus, TCR-induced alternative splicing augments MALT1 scaffolding to enhance downstream signalling and to promote optimal T-cell activation

Diagnostic applications of next generation sequencing: working towards quality standards

Over the past 6 years, next generation sequencing (NGS) has been established as a valuable high-throughput method for research in molecular genetics and has successfully been employed in the identification of rare and common genetic variations. All major NGS technology companies providing commercially available instruments (Roche 454, Illumina, Life Technologies) have recently marketed bench top sequencing instruments with lower throughput and shorter run times, thereby broadening the applications of NGS and opening the technology to the potential use for clinical diagnostics. Although the high expectations regarding the discovery of new diagnostic targets and an overall reduction of cost have been achieved, technological challenges in instrument handling, robustness of the chemistry and data analysis need to be overcome. To facilitate the implementation of NGS as a routine method in molecular diagnostics, consistent quality standards need to be developed. Here the authors give an overview of the current standards in protocols and workflows and discuss possible approaches to define quality criteria for NGS in molecular genetic diagnostics

Dampness and moulds in relation to respiratory and allergic symptoms in children : results from phase two of the International Study of Asthma and Allergies in Childhood, (ISAAC Phase Two)

Many studies report that damp housing conditions are associated with respiratory symptoms. Less is known about mechanisms and possible effect modifiers. Studies of dampness in relation to allergic sensitization and eczema are scarce. Objective We study the influence of damp housing conditions world-wide on symptoms and objective outcomes. Cross-sectional studies of 8–12-year-old children in 20 countries used standardized methodology from Phase Two of the International Study of Asthma and Allergies in Childhood (ISAAC). Symptoms of asthma, rhinitis and eczema, plus residential exposure to dampness and moulds, were ascertained by parental questionnaires (n = 46 051). Skin examination, skin prick tests (n = 26 967) and hypertonic saline bronchial challenge (n = 5713) were performed. In subsamples stratified by wheeze (n = 1175), dust was sampled and analysed for house dust mite (HDM) allergens and endotoxin. Current exposure to dampness was more common for wheezy children (pooled odds ratio 1.58, 95% CI 1.40–1.79) and was associated with greater symptom severity among wheezers, irrespective of atopy. A significant (P < 0.01) adverse effect of dampness was also seen for cough and phlegm, rhinitis and reported eczema, but not for examined eczema, nor bronchial hyperresponsiveness. HDM sensitization was more common in damp homes (OR 1.16, 1.03–1.32). HDM-allergen levels were higher in damp homes and were positively associated with HDM-sensitization, but not wheeze. A consistent association of dampness with respiratory and other symptoms was found in both affluent and non-affluent countries, among both atopic and non-atopic children. HDM exposure and sensitization may contribute, but the link seems to be related principally to non-atopic mechanisms.peer-reviewe

Alternde Gesellschaften in Europa. Empirische Untersuchungen mit Daten des SHARE

Dieser Band präsentiert drei ausgewählte empirische Studien, die im Rahmen des Bevölkerungswissenschaftlichen Forschungspraktikums an der Universität Bamberg entstanden sind. Der erste Beitrag beschäftigt sich mit „familialen Transferregimes“ in Europa, dem privaten Äquivalent zu öffentlichen Wohlfahrtsstaatsregimes. Im Mittelpunkt der Analyse steht die Frage, ob und wie sich osteuropäische Länder von nord-, west- und südeuropäischen Regimetypen unterscheiden. Der zweite Beitrag untersucht, ob sich ältere Menschen nach dem Renteneintritt gleichbleibend, vermehrt oder seltener ehrenamtlich engagieren. Der dritte Beitrag konzentriert sich ebenfalls auf die Effekte des Renteneintritts. Diese Arbeit geht der Frage nach, ob die Verrentung für ältere Menschen ein stressauslösendes Ereignis ist, das den gesundheitlichen Abbau beschleunigt. Die Autorinnen und Autoren untersuchen diese aktuellen sozialwissenschaftlichen Fragestellungen mit Daten der ersten beiden Wellen des Survey of Health, Ageing and Retirement in Europe (SHARE)

Residential PM2.5 exposure and the nasal methylome in children

Rationale: PM2.5-induced adverse effects on respiratory health may be driven by epigenetic modifications in airway cells. The potential impact of exposure duration on epigenetic alterations in the airways is not yet known. Objectives: We aimed to study associations of fine particulate matter PM2.5 exposure with DNA methylation in nasal cells. Methods: We conducted nasal epigenome-wide association analyses within 503 children from Project Viva (mean age 12.9 y), and examined various exposure durations (1-day, 1-week, 1-month, 3-months and 1-year) prior to nasal sampling. We used residential addresses to estimate average daily PM2.5 at 1 km resolution. We collected nasal swabs from the anterior nares and measured DNA methylation (DNAm) using the Illumina Methylation EPIC BeadChip. We tested 719,075 high quality autosomal CpGs using CpG-by-CpG and regional DNAm analyses controlling for multiple comparisons, and adjusted for maternal education, household smokers, child sex, race/ethnicity, BMI z-score, age, season at sample collection and cell-type heterogeneity. We further corrected for bias and genomic inflation. We tested for replication in a cohort from the Netherlands (PIAMA). Results: In adjusted analyses, we found 362 CpGs associated with 1-year PM2.5 (FDR < 0.05), 20 CpGs passing Bonferroni correction (P < 7.0 x 10(-8)) and 10 Differentially Methylated Regions (DMRs). In 445 PIAMA participants (mean age 16.3 years) 11 of 203 available CpGs replicated at P < 0.05. We observed differential DNAm at/ near genes implicated in cell cycle, immune and inflammatory responses. There were no CpGs or regions associated with PM2.5 levels at 1-day, 1-week, or 1-month prior to sample collection, although 2 CpGs were associated with past 3-month PM2.5. Conclusion: We observed wide-spread DNAm variability associated with average past year PM2.5 exposure but we did not detect associations with shorter-term exposure. Our results suggest that nasal DNAm marks reflect chronic air pollution exposure

Еволюція підходів до виділення факторів зміцнення конкурентних позицій підприємств

В статье исследовано развитие теоретической базы дисциплин, которые рассматривают конкурентное позиционирование предприятий. На основе обобщения дисциплинарных подходов к определению факторов укрепления конкурентных позиций предприятий выделено и охарактеризовано этапы развития последних. Сформулированы выводы относительно пригодности использования различных подходов для формирования адекватного современным условиям функционирования предприятий механизма достижения, поддержки и укрепления их конкурентных позиций.У статті досліджено розвиток теоретичної бази дисциплін, що розглядають конкурентне позиціонування підприємств. На основі узагальнення дисциплінарних підходів до визначення факторів зміцнення конкурентних позицій підприємств виділено та охарактеризовано етапи розвитку останніх. Сформульовано висновки відносно придатності використання різних підходів для формування адекватного сучасним умовам функціонування підприємств механізму досягнення, підтримки і зміцнення їх конкурентних позицій.Development of theoretical base of disciplines which examine the competition positioning is explored in the article. On the basis of generalization of disciplinary approaches to determination of factors of competition positions of enterprises it is selected and described the stages of development of it. Conclusions are formulated in relation to the fitness of the use of different approaches for forming of functioning of enterprises of mechanism of achievement, support and strengthening of their competition positions adequate to the modern terms