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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

Darování - srovnávací studie / Donation - comparative study

Hejduková, Martina January 2014 (has links)
Donation is not only a transfer of property, but it is a proof of certain relationship between the donor and the donee, which results from the liberality and altruism of the donor. Therefore it is understandable that majority of donations take place in the frame of family relations, they appear almost every day and they present a highly used contractual type in all legal orders. The legal regulation of donation has been significantly extended by the new civil code (Act no. 89/2012 coll. civil code) compared to the previous regulation and therefore is more compact and detailed, it has been also extended of another reason for revocation of donation, namely for impoverishment of the donor, furthermore the donatio mortis causa, which has been forbidden by the previous civil code has returned to the current regulation. In spite of enactment of new regulation some questions remain unsolved or new questions arise which will have to be answered by the currently non-existent specialized literature and judicial decisions. The aim of the submitted diploma thesis was to evaluate, whether the current legal regulation of donation contract can stand in comparison with the other European regulations, contained it civil codes with long-standing tradition whether it exceeds them in some directions, which deficiencies...
292

Effet de la radiothérapie sur la libération de microvésicules tumorales par des cellules de glioblastome / Impact of radiotherapy on the release of tumor microvesicles by glioblastoma cells

Ding, Haixia 10 December 2014 (has links)
Dans le glioblastome (GBM), la radiothérapie est un outil thérapeutique essentiel. Néanmoins, la récidive post-irradiation est quasiment inévitable, en raison de l’émergence d'une sous-population de cellules cancéreuses particulièrement radiorésistantes présentant une meilleure capacité proliférative, invasive et pro-angiogénique. Notre étude in vitro a cherché à déterminer comment les cellules cancéreuses survivantes à l’irradiation pouvaient affecter la fonction des cellules tumorales voisines et les cellules endothéliales non irradiées, en focalisant notre attention sur l’échange des signaux intercellulaires, à savoir, les facteurs solubles et les microvésicules tumorales (TMVs). La radiothérapie induit principalement un ralentissement de la prolifération des cellules de glioblastome (T98G et U87) et une mort cellulaire retardée (clonogénique) de 50-60%, sans engendrer d’apoptose. Grâce au suivi de la croissance cellulaire à long terme (via le système xCELLigence) et un test de blessure, nous avons confirmé que les cellules de glioblastome survivantes après irradiation libèrent des signaux qui peuvent modifier les fonctions de cellules endothéliales HUVEC et de cellules tumorales non-irradiées. Outre la sécrétion de certains facteurs solubles connus (VEGF, uPA), nous avons pu objectiver, en utilisant la microscopie électronique à balayage, le Nanoparticle Tracking Analysis (NTA), la libération de microvésicules tumorales (TMVs), dont la taille était globalement inférieure à 500 nm. Par NTA et cytométrie en flux, nous avons montré que cette libération de TMVs (exosome + "shedding vesicles"), peut être significativement stimulée par l’irradiation dans les 2 lignées, de façon temps-dépendant. D’après nos analyses protéomiques, les facteurs solubles tels que le VEGF ou l’IL-8, connus pour être des facteurs pro-angiogéniques, contribueraient plutôt à favoriser la survie, voire la prolifération, des cellules HUVEC, tandis que les TMVs libérées après irradiation, ont significativement modifié la capacité de migration des HUVEC et des cellules tumorales non-irradiées. Les propriétés pro-migratoires des TMVs pourraient en ce sens, contribuer aux processus de récidive dans les glioblastomes après irradiation / Radiation therapy is a major therapeutic tool for glioblastoma (GBM). However, the post-radiation recurrence is almost inevitable, due to the emergence of a subpopulation of radioresistant cancer cells with greater proliferative, invasive, and proangiogenic capacities. The objective of this study was to investigate in vitro how irradiated cancer cells affect the function of untreated neighboring tumor cells and endothelial cells, focusing on signals exchange initiated by irradiation, such as soluble factors and tumor microvesicles (TMVs). Radiotherapy has slowed down the proliferation of GBM cells (T98G, U87) and induced mitotic death of 50-60%, without significant apoptosis. Through long-term monitoring of cell growth (xCELLigence) and wound-healing assay, we have confirmed that surviving GBM cells after irradiation release signals that can change the functions of endothelial cells HUVEC and non-irradiated tumor cells. In addition to the secretion of known soluble factors (VEGF, uPA), we were able to show using scanning electron microscopy and the Nanoparticle Tracking Analysis (NTA), the release of tumor microvesicles (TMVS), whose size was generally less than 500 nm. By NTA and flow cytometry, we have shown that the release of TMVs (exosome + "shedding vesicles") can be significantly stimulated by irradiation in two lines, in a time-dependent manner. According to the proteomics analysis, soluble factors such as VEGF or IL-8, well known as pro-angiogenic factors, rather contribute to promote the survival or proliferation of HUVEC, while the released TMVs after irradiation, significantly altered the migration abilities of non-irradiated HUVEC and tumor cells. The pro-migratory properties of TMVs could thus contribute to glioblastoma recurrence after irradiation
293

L’esprit antilatin à Byzance (XIe-XVe siècle) / The antilatin spirit in Byzantium (XIth - XVth century)

Ritsou, Chryso 22 September 2017 (has links)
L’objectif de cette thèse est d’apporter un point de vue différent concernant les relations entre les Byzantins et les Latins, par rapport à l’historiographie byzantine traditionnelle qui les présente d’une manière linéaire : de l’entente et de la coopération à la grande hostilité, qui parvint à son comble en 1204 avec la prise de Constantinople par les croisés et qui persista jusqu'à la fin de Byzance. Cette étude se focalise sur l’analyse la plus fine possible des rapports et des perceptions des Byzantins à l’égard des Latins, qui varièrent en fonction des circonstances sur le plan politique, économique et culturel/religieux, des particularités géographiques, des classes sociales byzantines et des intérêts ou des liens individuels. Sa valeur ajoutée principale est la présentation exhaustive du sujet de l’esprit antilatin à Byzance dans son ensemble, à la fois en termes de composition de thèmes et de durée chronologique, couvrant tous les volets et tous les facteurs qui le forment et qui l’influencent, ainsi que toutes les périodes pendant lesquelles il subsiste. Elle dévoile que le pro-latinisme était bien présent au sein de la société byzantine concomitant à des tendances et des comportements d’antilatinisme et que les Latins étaient en réalité beaucoup plus appréciés par les Byzantins que ne le laissent entendre les sources byzantines de l'époque. / The aim of this thesis is to provide a different perspective on the relations between Byzantines and the Latins, compared with the traditional Byzantine historiography which presents them in a linear way: from harmony and cooperation to great hostility, which reached its height in 1204 with the capture of Constantinople by the Crusaders and which persisted until the end of Byzantium. This study focuses on the finest analysis of the relations and perceptions of the Byzantines towards the Latins, which varied according to political, economic and cultural/religious circumstances, geographical particularities, byzantine social classes and individual interests or connections. Its main added value is the comprehensive presentation of the topic of the antilatin spirit in Byzantium as a whole, both in terms of the composition of themes and chronological duration, covering all the components and all the factors that form it and influence it, as well as all periods during which it persists. It reveals that pro-latinism was present in Byzantine society concomitant with tendencies and behaviors of antilatinism and that the Latins were in fact much more appreciated by the Byzantines than the byzantine sources of that time lead us to believe.
294

Život a díla Jindřicha Malšínského / Life and works by Jindřich Malšínský

ŠÍMOVÁ, Kateřina January 2018 (has links)
This Master's thesis deals with the life and work of the South Bohemian educator and writer Jindřich Malšínský. The thesis is divided into two parts. The first part aims to describe by means of the biographical method the writers biography. The second part includes selected work of J. Malšínský with a specific focus on the interpretation of the novel called Principál by means of hermeneutic approach.
295

Um confronto político no presidencialismo de coalizão : os resultados do confronto entre o movimento LGBT e o movimento cristão pró-vida e prófamília (2003-2014)

Pereira, Matheus Mazzilli January 2018 (has links)
o movimento de lésbicas, gays, bissexuais, travestis e transexuais (LGBT) e o movimento cristão pró-vida e pró-família se engajaram em um confronto político em torno das demandas do primeiro desses movimentos ao Governo Federal. Ao longo desse período – em especial, a partir do primeiro Governo Dilma Rousseff (2011-2014) – os resultados políticos desse confronto variaram, passando a favorecer em maior medida o movimento cristão conservador. Essa variação vai de encontro às expectativas de estudos sobre os impactos de oportunidades políticas sobre os resultados políticos de confrontos, na medida em que, ao longo do período analisado, em primeiro lugar, um mesmo partido se manteve a frente da chefia do Executivo e, em segundo lugar, ativistas LGBT se mantiveram ativos em ministérios e secretarias do Governo Federal. Essa tese tem como principal objetivo explicar as variações nos resultados políticos desse confronto. Para atingir esse objetivo, realizei entrevistas com ativistas desses movimentos, com burocratas ativistas LGBT que atuaram em órgãos do Governo Federal e com assessores ligados à Frente Parlamentar Evangélica (FPE) e à Frente Parlamentar de Defesa da Cidadania LGBT (FPLGBT). Também utilizei dados do Portal da Transparência e de outras fontes oficiais para mapear iniciativas e recursos do Governo Federal transferidos por meio de ações voltadas às demandas do movimento LGBT. Por fim, mobilizei dados do portal da Câmara dos Deputados e do Senado para identificar variações na presença de parlamentares da FPE em coalizões de governo, na sua ocupação de espaços estratégicos no Congresso Nacional e em seu uso de requerimentos de informação e de projetos de decreto legislativo. A partir da análise desses dados, identifiquei os mecanismos de oportunidade e ameaça que conformam o processo político de gerenciamento de coalizões governamentais e que impactaram os resultados políticos desse confronto. Os resultados dessa investigação sugerem que as dinâmicas e os resultados do confronto político entre a FPLGBT e a FPE no Congresso Nacional passaram a favorecer essa última frente a partir do primeiro Governo Dilma. Com suas vitórias nesse confronto, a FPE se consolidou como um jogador importante no processo de gerenciamento de coalizões de governo, algo inesperado para literatura sobre esse tema, que indica que os partidos políticos são os atores capazes de negociar acordos com a chefia do Executivo. Assim, a FPE passou pressionar a chefia do Executivo em direção aos seus interesses e preferências que, por sua vez, passou a intervir sobre sua burocracia de forma a obstaculizar a ação de ativistas LGBT que se engajavam em confrontos políticos na Esplanada dos Ministérios. Dessa forma, apesar de sua penetração em instituições políticas, burocratas ativistas LGBT não puderam manter o nível de produção de resultados políticos positivos para o movimento LGBT. A partir desses resultados, sugiro como principal contribuição dessa tese que, para explicar variações nos resultados políticos de confrontos políticos no Brasil, é necessário compreender como processos de gerenciamento de coalizões governamentais afetam oportunidades e ameaças que facilitam ou obstaculizam a ação de movimentos sociais. / During the first three Partido dos Trabalhadores’ federal administrations, the Brazilian lesbians, gays, bisexuals, and transgenders movement (LGBT) and pro-life and pro-family christian movement engaged in an episode of contention around the demands of the first of these movements to the Federal Government. During this period – and particularly since the first Rousseff administration (2011-2014) – the political outcomes of this episode of contention varied in favor of the christian conservative movement. This variation challenges the studies on the impacts of opportunities over the political outcomes of political contention, first, because the same party was chief Executive of the country during this period and, second, because LGBT activists maintained their actions inside federal state secretaries. This dissertation aims at explaining the variations of this political contention’s political outcomes. To achieve this goal, I interviewed those movements' activists, LGBT bureaucrat activists that worked in federal state secretaries, and parliamentary assistants related to the Frente Parlamentar Evangélica (FPE) and to the Frente Parlamentar de Defesa da Cidadania LGBT (FPLGBT). I also mobilized data from official sources to map state initiatives and investments on actions related to LGBT demands. Finally, I used data from the Câmara dos Deputados’ and the Senado’s web pages to identify variations in the number of FPE parliamentarians in government coalitions, in the occupation of strategic spaces in the National Congress by these parliamentarians, and in their use of two legislative instruments, the requerimentos de informação and the projetos de decreto legislativo. Analyzing this data, I identified the mechanisms of opportunity and threat which conform the political process of government coalition management and affected the political outcomes of this episode of contention. The data suggests that the dynamics and outcomes of the political contention between the FPLGBT and the FPE in the National Congress began to favor the last of these parliamentary fronts since the first Rousseff administration. With those victories, the FPE consolidated itself as an important player in the government coalition management political process, something unexpected for the literature on this subject, that suggests that political parties are the actors capable of negotiating agreements with the chief of the Executive. The FPE started to press the chief Executive toward its interests and preferences who, on its turn, stated to intervene over its own bureaucracy, creating obstacles for the actions of LGBT activists that were engaged in contentious politics in state secretaries. Therefore, despite of its penetration in political institutions, LGBT bureaucrat activists could not afford to maintain their level of production of political outcomes for the LGBT movement. From this data, as the main contribution of this dissertation, I suggest that, in order to explain the variation of political outcomes of contentious politics in Brazil, it is necessary to understand how government coalition management processes affect the opportunities and threats which facilitate or hinder the action of social movements.
296

Rôle du stress oxydant au niveau hépatique et rénal dans la toxicité de l’uranium après exposition chronique / Role of oxidative stress in liver and kidney in uranium toxicity after chronic exposure

Poisson-Moreau de Lizorieux, Clémentine 20 December 2013 (has links)
L’Uranium (U) est un métal lourd radioactif dispersé dans l’environnement. Du fait de cette présence naturelle mais aussi de ses applications civiles et militaires, la population générale peut être exposée à l’U par ingestion d’eau de boisson ou d’aliments contaminés. Le système pro/anti-oxydant est un système de défense fréquemment impliqué lors d'une exposition aiguë à l'uranium. L’objectif de cette thèse est d’étudier le rôle du système pro/anti-oxydant après contamination chronique à l’U dans le foie et les reins. Après contamination chronique de rats à différentes concentrations d’U, une accumulation dose dépendante de l’U dans les organes -jusqu'à 6 µg/g dans les reins- ainsi qu’une localisation préférentielle de l’U dans le noyau des cellules du tube contourné proximal sont observées. L’absence de néphrotoxicité observée, même à la plus forte concentration, pourrait s’expliquer par le renforcement du système anti-oxydant et notamment l’augmentation du taux de glutathion. L’étude des effets de la contamination à l’U chez un modèle déficient pour Nrf2, facteur de transcription cytoprotecteur impliqué dans la défense anti-oxydante, a mis en évidence une accumulation d’U plus importante chez les animaux Nrf2 -/-. Néanmoins, les effets biologiques de l’U sur le système pro/anti-oxydant ne semblent pas impliquer Nrf2. Par ailleurs, il existe une corrélation entre la localisation de l’U dans des cellules HepG2 en culture et les effets biologiques sur ce système après exposition à de faibles concentrations d’U. Ce radionucléide se localise dans les noyaux sous forme soluble et l’apparition de précipités est corrélée à la mise en place de mécanismes d’adaptation qui sont ensuite débordés au cours du temps et de la concentration, laissant apparaître une toxicité cellulaire. L’ensemble de ces résultats suggèrent que le renforcement du système anti-oxydant serait un mécanisme d’adaptation après exposition chronique à faible concentration d’U. / Uranium is a radioactive heavy metal found in the environment. Due to its natural presence and to civil and militaries activities, general population can be exposed to U throughout drinking water or contaminated food. The pro/anti-oxidative system is a defense system which is often implicated in case of acute exposure to U. The aim of this thesis is to study the role of the pro/anti-oxidative system after chronic exposure to U in the liver and the kidney. After chronic exposure of rats to different U concentrations, this radionuclide accumulated in the organs in proportion to U intake; until 6 µg.g-1 of kidney tissues. U is localized in nucleus of the proximal tubular cells of the kidney. No nephrotoxicity was described even for the higher U level in drinking water and a reinforcement of the pro/anti-oxidative system with an increase in glutathione is observed. The study of U internal contamination in Nrf2 deficient mice, a cytoprotective transcription factor involved in the anti-oxidative defense has been realized. U accumulate more in Nrf2 -/- mice than in WT mice but the biologic effects of U on the pro/anti-oxidative system did not seem to implicate Nrf2. At the cell level, a correlation between U distribution in HepG2 cells and the biological effects on this system is observed after U exposure at low concentrations. Soluble distribution of U is observed in cell nucleus. The apparition of U precipitates is correlated to the establishment of the adaptive mechanisms overtime which are overwhelmed and lead to a cellular toxicity at higher U level. In conclusion, these results suggest that the reinforcement of pro/anti-oxidative system could be an adaptive mechanism after chronic exposure at low U concentration.
297

Kinematische Analyse ebener und räumlicher Getriebestrukturen mit Hilfe von Motion-Skeletten

Heine, Andreas 13 May 2009 (has links) (PDF)
Der vorliegende Beitrag befasst sich mit dem Einsatz von Motion-Skeletten bei der kinematischen Analyse von zwei- und dreidimensionalen Getriebestrukturen. Im ersten Teil werden verschiedene Möglichkeiten aufgezeigt, welche Pro/ENGINEER für die Mechanismus-Analyse bietet und bezüglich ihrer Eignung für kinematische Strukturen verglichen. Am Beispiel einer exzentrischen Schubkurbel wird anschließend der Aufbau und die Funktionsweise eines Motion-Skelettes erklärt. Neben der reinen kinematischen Analyse einer solchen Struktur wird auch der Einsatz von BMX zur Optimierung von Koppelgetrieben gezeigt.
298

Um confronto político no presidencialismo de coalizão : os resultados do confronto entre o movimento LGBT e o movimento cristão pró-vida e prófamília (2003-2014)

Pereira, Matheus Mazzilli January 2018 (has links)
o movimento de lésbicas, gays, bissexuais, travestis e transexuais (LGBT) e o movimento cristão pró-vida e pró-família se engajaram em um confronto político em torno das demandas do primeiro desses movimentos ao Governo Federal. Ao longo desse período – em especial, a partir do primeiro Governo Dilma Rousseff (2011-2014) – os resultados políticos desse confronto variaram, passando a favorecer em maior medida o movimento cristão conservador. Essa variação vai de encontro às expectativas de estudos sobre os impactos de oportunidades políticas sobre os resultados políticos de confrontos, na medida em que, ao longo do período analisado, em primeiro lugar, um mesmo partido se manteve a frente da chefia do Executivo e, em segundo lugar, ativistas LGBT se mantiveram ativos em ministérios e secretarias do Governo Federal. Essa tese tem como principal objetivo explicar as variações nos resultados políticos desse confronto. Para atingir esse objetivo, realizei entrevistas com ativistas desses movimentos, com burocratas ativistas LGBT que atuaram em órgãos do Governo Federal e com assessores ligados à Frente Parlamentar Evangélica (FPE) e à Frente Parlamentar de Defesa da Cidadania LGBT (FPLGBT). Também utilizei dados do Portal da Transparência e de outras fontes oficiais para mapear iniciativas e recursos do Governo Federal transferidos por meio de ações voltadas às demandas do movimento LGBT. Por fim, mobilizei dados do portal da Câmara dos Deputados e do Senado para identificar variações na presença de parlamentares da FPE em coalizões de governo, na sua ocupação de espaços estratégicos no Congresso Nacional e em seu uso de requerimentos de informação e de projetos de decreto legislativo. A partir da análise desses dados, identifiquei os mecanismos de oportunidade e ameaça que conformam o processo político de gerenciamento de coalizões governamentais e que impactaram os resultados políticos desse confronto. Os resultados dessa investigação sugerem que as dinâmicas e os resultados do confronto político entre a FPLGBT e a FPE no Congresso Nacional passaram a favorecer essa última frente a partir do primeiro Governo Dilma. Com suas vitórias nesse confronto, a FPE se consolidou como um jogador importante no processo de gerenciamento de coalizões de governo, algo inesperado para literatura sobre esse tema, que indica que os partidos políticos são os atores capazes de negociar acordos com a chefia do Executivo. Assim, a FPE passou pressionar a chefia do Executivo em direção aos seus interesses e preferências que, por sua vez, passou a intervir sobre sua burocracia de forma a obstaculizar a ação de ativistas LGBT que se engajavam em confrontos políticos na Esplanada dos Ministérios. Dessa forma, apesar de sua penetração em instituições políticas, burocratas ativistas LGBT não puderam manter o nível de produção de resultados políticos positivos para o movimento LGBT. A partir desses resultados, sugiro como principal contribuição dessa tese que, para explicar variações nos resultados políticos de confrontos políticos no Brasil, é necessário compreender como processos de gerenciamento de coalizões governamentais afetam oportunidades e ameaças que facilitam ou obstaculizam a ação de movimentos sociais. / During the first three Partido dos Trabalhadores’ federal administrations, the Brazilian lesbians, gays, bisexuals, and transgenders movement (LGBT) and pro-life and pro-family christian movement engaged in an episode of contention around the demands of the first of these movements to the Federal Government. During this period – and particularly since the first Rousseff administration (2011-2014) – the political outcomes of this episode of contention varied in favor of the christian conservative movement. This variation challenges the studies on the impacts of opportunities over the political outcomes of political contention, first, because the same party was chief Executive of the country during this period and, second, because LGBT activists maintained their actions inside federal state secretaries. This dissertation aims at explaining the variations of this political contention’s political outcomes. To achieve this goal, I interviewed those movements' activists, LGBT bureaucrat activists that worked in federal state secretaries, and parliamentary assistants related to the Frente Parlamentar Evangélica (FPE) and to the Frente Parlamentar de Defesa da Cidadania LGBT (FPLGBT). I also mobilized data from official sources to map state initiatives and investments on actions related to LGBT demands. Finally, I used data from the Câmara dos Deputados’ and the Senado’s web pages to identify variations in the number of FPE parliamentarians in government coalitions, in the occupation of strategic spaces in the National Congress by these parliamentarians, and in their use of two legislative instruments, the requerimentos de informação and the projetos de decreto legislativo. Analyzing this data, I identified the mechanisms of opportunity and threat which conform the political process of government coalition management and affected the political outcomes of this episode of contention. The data suggests that the dynamics and outcomes of the political contention between the FPLGBT and the FPE in the National Congress began to favor the last of these parliamentary fronts since the first Rousseff administration. With those victories, the FPE consolidated itself as an important player in the government coalition management political process, something unexpected for the literature on this subject, that suggests that political parties are the actors capable of negotiating agreements with the chief of the Executive. The FPE started to press the chief Executive toward its interests and preferences who, on its turn, stated to intervene over its own bureaucracy, creating obstacles for the actions of LGBT activists that were engaged in contentious politics in state secretaries. Therefore, despite of its penetration in political institutions, LGBT bureaucrat activists could not afford to maintain their level of production of political outcomes for the LGBT movement. From this data, as the main contribution of this dissertation, I suggest that, in order to explain the variation of political outcomes of contentious politics in Brazil, it is necessary to understand how government coalition management processes affect the opportunities and threats which facilitate or hinder the action of social movements.
299

Potenciální přínosy celosvětové harmonizace finančního výkaznictví pro SME

Trčková, Veronika January 2014 (has links)
This thesis focuses on global harmonisation of SME financial reporting and possible benefits of this harmonisation. The first part of this thesis consists of a literature review stressing the importance of SME sector and presents the history of IFRS for SME. Follows the summary of papers concerning IFRS and IFRS for SME implementation. These papers conclusions with the factors influencing the acceptance of this standard worldwide are summarised in a SWOT analysis. The second part of this thesis is testing hypotheses that arose based on the secondary research of previous papers, presented in the first part.
300

Análise molecular da proteína HC-Pro (Helper Component-Proteinase) e seu papel na relação patógeno-hospedeiro

Frangioni, Desiré Spada dos Santos [UNESP] 29 November 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:34:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-29Bitstream added on 2014-06-13T19:24:02Z : No. of bitstreams: 1 frangioni_dss_dr_botfca.pdf: 2302780 bytes, checksum: a3bab8cdfaa8a760d70900c13de09d8d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O gênero Potyvirus é um dos maiores dentre os vírus de planta com genoma composto por RNA. O genoma dos potyvirus codifica um único polipeptídeo que é processado por três proteinases virais que originam todas as proteínas necessárias para complementar o ciclo da infecção. A proteína HC-Pro (Helper Component proteinase) é uma dessas proteínas multifuncionais que está envolvida na amplificação do genoma, transmissão por afídeo, movimento sistêmico e local, supressão do silenciamento gênico e proteólise. Nesse trabalho, foi realizada a substituição funcional de parte da região codificadora da HC-Pro do Lettuce mosaic virus (LMV) com a porção correspondente à HC-Pro do Potato virus Y (PVY), com o objetivo de melhor compreender os papéis dessa proteína no ciclo de infecção dos potyvirus. O LMV e o PVY diferem tanto em patogenicidade quanto em círculo de hospedeiros. O LMV infecta, principalmente, espécies da família Asteraceae (alface) enquanto o PVY infecta Solanaceae. Para avaliar o efeito de tal substituição na infectividade, dois vírus quiméricos foram construídos: um clone infeccioso de LMV contendo a HC-Pro selvagem do PVY (estendendo-se dos aminoácidos 1 a 352) e um segundo clone contendo a HC-Pro de PVY com mutação no motivo conservado IGN (mutado para RPN). Os vírus recombinantes e o LMV selvagem foram inoculados via biobalística em folhas de plântulas de alface cv. Trocadero (suscetível ao LMV). A presença e a natureza das progênies virais... / The genus Potyvirus is one of the largest genera of plant RNA viruses. The potyvirus genome encodes a single polypeptide that is processed by three viral proteinases to yield all viral proteins needed for the infection cycle. One of these proteins is the multifunctional helper component proteinase (HC-Pro), which is involved in genome amplification, aphid transmission, local and systemic movement, suppression of gene silencing and proteolysis. To gain further understanding of the roles of this protein in the Potyvirus life cycle, the functional replacement of the HC-Pro coding region of Lettuce mosaic virus (LMV) with its corresponding counterpart of Potato virus Y (PVY) was performed. These viruses differ both in pathogenicity and in host range. LMV infects mainly Asteraceae while PVY infects Solanaceae. To assess the functional requirement of a homologous HC-Pro in infectivity, two different chimeric viruses were constructed i. e: a full-length LMV containing a wild type PVY HC-Pro (1aa to 352aa) and a full-length LMV containing a PVY HC-Pro with a mutation in the IGN motif (exchanged to RNP). The chimeras, and wild type LMV, were inoculated by biolistic in young lettuce plants. The presence and nature of viral progenies were checked by RT-PCR amplification followed by sequencing. All recombinant viruses were infectious and displayed systemic infection although the symptoms were weak when compared to the wild type LMV. The viruses accumulation were evaluated by differential cycles in the RT-PCR. The LMV wild type was amplified by 30 cycles while the chimerics viruses needed 40 cycles. Therefore this result indicating that the chimeric viruses titer were lower than LMV wild type. The results 4 described here demonstrated that the main biological functions of HC-Pro can be accomplished by heterologous protein.

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