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Variation génétique et potentiel d'adaptation locale chez le saumon atlantique, Salmo salar : structure de population, adaptation immunitaire et résistance aux pathogènesDionne, Mélanie 13 April 2018 (has links)
Un des objectifs ultimes en écologie évolutive est de comprendre les mécanismes responsables du maintien de la biodiversité en milieu naturel. La biodiversité englobe la diversité des écosystèmes, des espèces, des populations et aussi la diversité génétique associée à une espèce donnée. Même à l’intérieur d’une espèce, on peut observer une grande diversité de phénotypes et de génotypes résultant de l’interaction entre la sélection naturelle, le flux génique, la dérive génétique et les mutations. L’objectif central de cette thèse est d’évaluer la variabilité génétique et le potentiel d’adaptation chez le saumon atlantique, Salmo salar, en milieu naturel. L’analyse de 51 rivières à saumon aux marqueurs microsatellites révèle une structure de populations hiérarchique et suggère l’existence de sept groupes régionaux au Québec, Labrador et Nouveau-Brunswick, Canada. Les analyses en génétique du paysage suggèrent l’influence prédominante du flux génique et de l’adaptation thermique dans l’établissement de la différentiation génétique. Des évidences indirectes suggèrent également que les immigrants provenant d’un autre groupe régional ont un succès reproducteur moindre dans leur nouveau milieu que les résidents. Différents niveaux de structuration génétique ont aussi été observés à l’intérieur même de certaines rivières, remettant en cause la gestion par rivière chez cette espèce. La variabilité à grande échelle d’un gène d’immunocompétence, le gène du Complexe Majeur d’Histocompatibilité (CMH) classe IIβ, démontre que la diversité génétique au CMH augmente avec la température et la diversité bactérienne présente en rivière, contrairement au patron observé aux microsatellites. L’augmentation de la diversité au CMH avec la température est plus prononcée aux sites de liaison aux pathogènes qu’aux autres sites moléculaires, suggérant une influence plausible de la diversité des pathogènes, elle-même dépendante de la température, sur l’adaptation locale du saumon atlantique. Finalement, l’étude des infections pathogéniques chez les saumons juvéniles révèle un taux d’infection accru en début de saison estivale dans les rivières de la rive sud du Saint-Laurent, concordant avec les pressions de sélection du milieu. Un parasite prédominant et possiblement récemment introduit, un myxozoaire du genre Myxobolus, a été découvert chez les jeunes saumons et deux allèles CMH ont été identifiés comme étant associés à la résistance et à la susceptibilité face à cette infection, suggérant l’importance de la variation génétique présente au CMH pour faire face aux pathogènes dans un contexte de changement environnemental. Cette thèse ajoute à notre compréhension sur les mécanismes qui maintiennent la variabilité génétique et influencent l’adaptation locale chez le saumon atlantique sauvage grâce à des analyses novatrices en génétique du paysage, en structure de population et sur les patrons spatio-temporels d’infection en milieu naturel. / One of the central endeavors in evolutionary ecology is to understand the mechanisms responsible for natural biodiversity. Biodiversity is defined as the combined diversity of ecosystems, species, populations and the genetic diversity within a given species. Even within a species, a wide diversity of phenotypes and genotypes is often observed, resulting from the interaction between natural selection, gene flow, genetic drift and mutations. The central objective of this thesis was to assess the genetic variability and evaluate the potential for local adaptation in wild Atlantic salmon, Salmo salar. Analyses of neutral molecular markers in 51 salmon rivers revealed a hierarchical genetic structure and suggested the existence of seven regional groups in Québec, Labrador and New-Brunswick, Canada. Landscape genetic analyses suggested a predominant influence of gene flow and thermal regime adaptation in maintaining genetic differentiation. Indirect evidence also suggested that immigrants from a different regional group were less successful in establishing in the new environment compared to residents. Different extents of genetic structure were also found within some river systems, questioning the river-based management approach in Atlantic salmon. Large scale genetic variability at an immuno-competence gene, the Major Histocompatibility Complex (MHC) class IIβ gene, revealed that genetic diversity increased with increasing temperature and bacterial diversity in rivers contrary to patterns with neutral microsatelite markers. This increase in MHC diversity with temperature was more pronounced at the peptide-binding region involved in pathogen binding than at other molecular sites. These results agree with the hypothesized influence of temperature-associated pathogen diversity on local adaptation in Atlantic salmon. Finally, pathogen infections in juvenile salmon were found to be more frequent at the beginning of the summer in southern rather than northern rivers, in concordance with pathogen selection pressure in the wild. A predominant and possibly introduced pathogen, a myxozoa of the genus Myxobolus, was identified in juvenile salmon and two MHC alleles were found to be associated with resistance and susceptibility to that infection, suggesting the importance of MHC standing genetic variation for facing pathogens in a changing environment. This thesis contributes to our understanding on mechanisms maintaining genetic variability and influencing local adaptation in wild Atlantic salmon through analyses in landscape genetics, genetic population structure and patterns of spatio-temporal infectivity in nature.
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Ontographie du rapport à la terre à Chillimocco : rationalité et rituel dans l'agriculture d'un village andin au PérouLegoas Pena, Jorge 23 April 2018 (has links)
Cette thèse montre la façon dont les paysans-autochtones de Chillimocco (dans les Andes péruviennes) constituent leur rapport à la terre à travers l’activité agricole. Celle-ci est envisagée de façon à ne plus la considérer comme un ensemble de « techniques » qu’on impose sur la « nature » pour la soumettre, mais comme un continu qui associe du technique et du rituel et qui, ce faisant, établit un rapport symétrique entre hommes et terres. Nous faisons une description approfondie de la façon dont l’agriculture est menée dans ce village andin, afin de dégager les principes qu’elle met en place. La démarche analytique que nous suivons est double. Un premier niveau d’analyse est constitué par l’examen des catégories locales que dégage l’activité agricole. Elles-mêmes constituent un premier indice du rapport à la terre à Chillimocco, mais pour s’interroger à propos de la « rationalité » de ce rapport, on ne peut pas opérer une interpolation automatique. Un deuxième niveau d’analyse est alors opéré à l’aide d’une notion de rationalité révisée afin de la rendre abordable par l’anthropologie. Pour ce faire, on se sert de certains éléments de l’anthropologie symétrique qui nous permettent de remanier ladite notion et de l’investir des sens locaux dégagés par le premier niveau d’analyse. Les notions locales nous aident à envisager une rationalité sociale plus enracinée, mais aussi elles brisent nos catégories de départ et nous conduisent progressivement vers des notions plus aptes à saisir la différence ontologique que posent les Chillimoccokuna. La catégorie de « rituel », chère à l’anthropologie, est ainsi remise en question. Dans un premier moment, on met en œuvre un traitement du rituel cohérent avec la façon dont Edmund Leach (dépassant le rituel comme type d’action) l’envisageait comme un trait de l’action. Mais la considération de la condition ontologique des acteurs impliqués fait que cette thèse finisse par remettre en question la distinction entre traits rituels et traits techniques elle-même. Enfin, par notre approche qui va au-delà de la symétrie généralisée de Bruno Latour, par une préoccupation analytique autoréflexive fondée sur l’expérience, et par la prise en compte de formes d’existence multiples, ce travail établit une démarche que nous appelons d’ontographie. / This doctoral thesis shows how native peasants from Chillimocco (in the Peruvian Andes) establish a relationship with the land through agriculture. The latter is viewed not as a set of “techniques” imposed on “nature” to subject it, but as a continuum that combines technique and ritual and, in doing so, establishes a symmetrical relationship between human beings and lands. We describe in-depth how agriculture is carried out in this Andean village in order to bring out the principles it sets up. Our analytical work is twofold. A first level of analysis is constituted by the examination of local categories brought out by agricultural activities. These categories constitute a first marker of the relationship with the lands at Chillimocco, but to interrogate the “rationality” of this relationship one cannot undertake an automatic interpolation. Then a second level of analysis is undertaken with the help of a notion of “rationality” that has been revised in order to make it accessible to anthropology. To achieve this, we use some elements of the Symmetrical Anthropology that allow us to rework such notion and to endow it with the local meanings undertaken in the first level of analysis. The local notions help us not only to envision a more grounded social rationality, but also to unsettle our categories of departure; progressively leading us to more adapted notions to grasp the ontological difference revealed by the Chillimocco. Thus, the pertinence of “ritual, ” a category of great concern in the anthropological tradition is put into question. In a first moment, we treat ritual in agreement with how Edmund Leach visualized it, i.e. like a trait of all action (going beyond ritual as a type of action). However, the ontological condition of the actors involved, make that this dissertation also questions the distinction between ritual traits and technical traits. Finally, our approach that goes beyond Bruno Latour’s generalized symmetry, our self-reflexive analytical work based on experience, and our concern with multiple forms of existence, make of this work more an “ontographic” effort than a classical ethnography.
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Mudanças e continuidades na elite parlamentar de Goiás: 1982-2010 / Changes e continuities in the parliamentary elite of Goiás: 1982-2010MOTA, Regys Rodrigues da 08 August 2011 (has links)
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Previous issue date: 2011-08-08 / The goal of this research is to analyze the process of democratization of political elites observing changes and continuities in the profile of the parliamentarians in the composition of the Legislative Assembly of Goiás during the period 1982 to 2010. / A dissertação tem como objetivo analisar a elite política goiana observando mudanças e continuidades no perfil dos parlamentares presentes na composição da Assembléia Legislativa de Goiás durante o período de 1982 a 2010. Para tanto, o estudo foi desenvolvido por meio de pesquisa bibliográfica para aprofundamento teórico a respeito do tema Teoria das Elites e mediante pesquisa documental com a finalidade de analisar dados referentes ao perfil socioeconômico dos deputados da Assembléia Legislativa de Goiás.
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Dynamique des échanges de dioxyde de carbone de la pessière noire boréale de l'est du CanadaBergeron, Onil 13 April 2018 (has links)
Les émissions anthropogéniques de dioxyde de carbone ont changé le climat de la Terre. Les forêts boréales contiennent de vastes quantités de carbone (C) et peuvent donc jouer un rôle crucial dans le cycle du C global. Les pessières noires dominent la forêt boréale nord-américaine, il est donc nécessaire de comprendre leurs réponses à la variabilité du climat et aux perturbations écologiques telle la récolte forestière afin d’identifier les facteurs influençant les échanges de C entre la biosphère terrestre et l’atmosphère. Le premier chapitre de recherche (Chap. 3) présente une comparaison des échanges de C de trois pessières noires matures de différentes régions du Canada. Cette étude a montré que le sol plus chaud sous un couvert de neige plus épais en hiver et de faibles niveaux de lumière en juin au site de l’est du Canada, des conditions communes dans cette région, ont réduit la séquestration de C relativement aux sites du Canada central. Une paramétrisation générale à une échelle de temps mensuelle a suffit à caractériser la réponse des pessières noires matures aux conditions environnementales. Dans le deuxième chapitre de recherche (Chap. 4), le bilan de C et la réponse des échanges de C aux conditions environnementales de pessières noires mature et récemment récolté de l’est du Canada ont été quantifiés. Le bilan de C de ces pessières noires était davantage affecté par leur stade de développement que les variations interannuelles du climat. La réponse des échanges de C aux facteurs environnementaux a montré une plus forte variabilité entre et à l’intérieur des années au site récolté due à la structure dynamique de la végétation. Le troisième chapitre de recherche (Chap. 5) concerne les échanges de C du parterre forestier d’une pessière noire mature de l’est du Canada mesurés sur différents microsites. La respiration du sol et la photosynthèse du parterre forestier ont respectivement contribuées à 76-88% et 16-17% de la respiration et de la photosynthèse totales de l’écosystème. Les différences observées de réponse de la respiration du sol aux facteurs environnementaux suggèrent que le type de microsite peut refléter la variabilité spatiale de la respiration du sol. Ces trois études procurent de l’information utile pour paramétrer et modéliser la réponse de la forêt boréale aux variations du climat et aux perturbations écologiques. / Carbon dioxide emissions from human activities are changing the Earth’s climate. The boreal forest contains enormous carbon (C) stocks and hence it plays a critical role in the global C cycle. Black spruce ecosystems are the dominant cover type in the North American boreal forest, thus it is necessary to understand their response to both climate variability and to ecological disturbances such as forest harvest so as to identify the factors influencing C exchange between the biosphere and the atmosphere. The first research chapter (Chap. 3) of this thesis presents a comparison of C exchange for three old black spruce ecosystems located in different regions of Canada. This study showed that warmer soil under deeper snowpack in winter and low light levels in June at the eastern Canada site, which are common conditions in that region, reduced C sequestration relative to that of similar ecosystems in central Canada. Furthermore, a general parameterization at a monthly time resolution was sufficient for characterizing the physiological response of all three black spruce ecosystems to environmental conditions. In the second research chapter (Chap. 4), the C balance and the response of C exchange to environmental conditions of a mature and a recently harvested black spruce site in eastern Canada were quantified. The C balance of these black spruce ecosystems was more affected by their respective developmental stage than by inter-annual climate variability. The response of C exchange to environmental factors showed a greater between- and within-year variability at the harvested site due to the dynamic structure of the vegetation. The third research chapter (Chap. 5) examined forest floor C exchange for a mature black spruce site in eastern Canada measured on different microsites. Soil respiration and forest floor photosynthesis accounted for 76-88% and 16-17% of total ecosystem respiration photosynthesis, respectively. The observed differences of the response of soil respiration to environmental factors suggest that microsite can reflect the spatial variability of soil respiration. All three of these studies provide valuable information for parameterizing and modeling the response of boreal forests to climate variability and to ecological disturbance.
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Stylistic Evolution of the Motet Through the Sixteenth Century with Emphasis on the Style of PalestrinaCornelius, Merl V. 08 1900 (has links)
The mass and the motet are the most important musical components of the Catholic liturgy. The development of vocal polyphony in the Medieval Period culminated in the perfection of these forms in the sixteenth century. The purpose of this thesis is to give an account of the development of religious monody and polyphony that led to the inception of the motet in the early part of the thirteenth century; to show the development of the motet through the sixteenth century; to give a more detailed analysis of the style of Palestrina; and to emphasize the analysis with a stylistic examination of a Palestrina motet.
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Geração de \"Etiquetas de sequências expressas\" dirigidas para porções codificadoras dos genes (Orestes): identificação de novos genes humanos expressos em câncer de mama / Generation of \"Expressed sequence labels\" directed to coding portions of genes (Ores): identification of new human genes expressed in breast cancerCorrêa, Ricardo Garcia 16 February 2001 (has links)
Etiquetas de sequências expressas (ESTs) são fundamentais para a identificação de genes no genoma humano e para definir características de expressão gênica. Neste trabalho, descrevemos uma nova abordagem para a geração de bibliotecas de cDNA, utilizando iniciadores arbitrários para a produção, por PCR, de mini-bibliotecas a partir de mRNA derivado de câncer de mama. Clones destas bibliotecas foram sequenciadas para gerar 6029 ESTs. Utilizando esta abordagem, foi possível observar uma significante normalização das diferentes sub-populações de mRNA e amplificação preferencial de porções centrais dos genes. Análise bioinformática destas sequências mostra que 3.350 ESTs (56%) tem similaridade significante a sequências de DNA e/ou cDNA já conhecidas (sequências anotadas) descritas em diferentes organismos, e 1509 ESTs (25%) não possuem qualquer similaridade a diferentes bancos de dados. Dentre as sequências anotadas, identificamos algumas sequências com alta similaridade a genes conhecidos em diferentes organismos, indicando a descoberta de alguns genes homólogos possivelmente envolvidos com processos carcinogênicos. Como exemplo, isolamos e caracterizamos parcialmente (i) uma nova isoforma do gene NABC1 (novel amplified sequence in breast carcinoma 1), o qual é pouco expresso em tumores coloretais, (ii) um novo gene da família de semaforinas (moléculas de motilidade axonal) que apresenta uma baixa expressão em linhagens celulares de glioblastoma tratadas com ácido retinóico, um agente antitumoral e (iii) o gene ortólogo humano Notch 2, aparentemente superexpresso em tumores mamários com maior malignidade. / Expressed sequence tags (ESTs) are of fundamental importance for the identification of genes within the human genome and defining gene expression characteristics. In this work, we describe a new approach for generating cDNA libraries using essentially arbitrary primers to construct PCR-based minilibraries from breast tumor mRNA. Clones from these libraries were sequenced to generate 6,029 ESTs. Using this approach, we were able to observe a significant normalization of the different mRNA subpopulations and a preferential amplification of the central portions of the genes. Bioinformatic analysis of these sequences shows that 3,350 ESTs (56%) have significant similarity to known DNA and/or cDNA sequences (annotated sequences) from different organisms and 1,509 ESTs (25%) show no similarity to any sequences on different databases. From the annotated sequences, we have identified some sequences with high similarity to known genes from different organisms, indicating the discovery of some homologous genes possibly correlated with carcinogenic processes. For instance, we have isolated and partially characterized (i) a new NABC1 (novel amplified sequence in breast carcinoma 1) isoform which is downregulated in colorectal tumors, (ii) a novel semaphorin member of axon guidance molecules that is down-regulated in glioblastoma cell lines treated with all-trans-retinoic acid, an anti-tumor agent and (iii) the ortolog Notch 2 human gene, apparenty overexpressed in breast tumors with higher malignancy.
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O instituto do est?gio de car?ter n?o obrigat?rio sob a ?tica da teoria de Pierre Bordieu : um campo de luta para al?m do fazer e o saberCorr?a, Newton S?rgio Piant? 30 September 2014 (has links)
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Previous issue date: 2014-09-30 / Having in view the complex configuration of the social agents that, either direct or indirectly, make up the non-mandatory Institution of the On-the job-trainings in the State of Rio Grande do Sul, which involves students, companies, schools, and on-the-job training integration agents, this dissertation, by means of an exploratory qualitative researching, based on the Sociological Theory of Pierre Bourdieu, has the central target of examining the social dynamics that supports the program, mainly considering the way of organization and the influence that the several on-the-job-training agents exert on it. Considering, furthermore, the changes caused by the recent legislation on the non-mandatory on-the-job training, which has tried to bring back its pedagogical purposes and to humanize the relations between trainees and firms, the second focusing of this paper approaches the possible consequences resulting from such legislation for the program. / Tendo em vista a complexa configura??o de agentes sociais que, direta ou indiretamente, comp?em o Instituto dos Est?gios n?o obrigat?rios no Estado do Rio Grande do Sul, a qual envolve estudantes, empresas, institui??es de ensino e agentes de integra??o de est?gios, a presente disserta??o, por meio de uma pesquisa qualitativa de car?ter explorat?rio e tendo como base a Teoria Sociol?gica de Pierre Bourdieu, possui como objetivo central examinar a din?mica social que sustenta o programa, sobremodo quanto ? forma de organiza??o e ? influ?ncia que os diversos agentes de integra??o de est?gios exercem sobre ele. Considerando, ainda, as altera??es trazidas pela ?ltima legisla??o aos est?gios n?o obrigat?rios, a qual procurava resgatar seus prop?sitos pedag?gicos e humanizar as rela??es entre estagi?rios e empresas, o segundo foco deste estudo recai sobre as poss?veis consequ?ncias advindas desta legisla??o para o programa.
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Fun??o do est?gio curricular obrigat?rio no IFET Cear? - Campus Crato, na perspectiva discente / Analysis of the function of the mandatory curricular training period in the farming technician course in Intituto Federal do Cear? ? Campus Crato, Cear?, Brazil, in the learning perspectiveSANTOS, Jucier Gon?alves dos 30 May 2012 (has links)
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Previous issue date: 2012-05-30 / The goal of this research was to investigate the role that the required period of training performs in the formation of a farming technician of Instituto Federal de Educa??o, Ci?ncia e Tecnologia do Cear? ? Campus Crato, from the perspective of the students. As we know, the mandatory training period is a complementary stage of the learning process and involves a pedagogical structure, from a suitable curriculum to small actions in the school environment, so that we can turn this activity into a reflexive action to develop a coherent relation between practice and theory. We chose the qualitative approach aiming to achieve a better comprehension and to give meanings to the analyzed phenomena. The instruments used to collect the data were questionnaires with open questions. The target of this research was the former students of the Integrated Technician Course who finished in 2010. These instruments enabled us to identify some discrepancies related to the articulation between school, training, and the job market, which have been compromising the role of the farming technician in his/her area of insertion. It's important to highlight that, in addition to these aspects, we aimed to gather specific laws and decrees which influenced the development of this work in Brazil. We endeavored, also, to approach the training practice in a perspective of approximation between propaedeutic and technical teaching, taken as able to provide the student with education to face the challenges of the world of work. / Esta pesquisa teve como objetivo investigar o papel que o est?gio curricular obrigat?rio (ECO) vem desempenhando na forma??o do T?cnico em Agropecu?ria do Instituto Federal de Educa??o do Cear?, Campus Crato, a partir da perspectiva dos discentes. Como se sabe, o est?gio Curricular Obrigat?rio ? uma etapa de complementaridade do processo de aprendizagem e envolve uma estrutura pedag?gica que vai desde curr?culos adequados at? pequenas a??es no ?mbito do ambiente escolar, a fim de que se possa fazer dessa atividade uma a??o reflexiva com vista a desenvolver de forma coesa a rela??o entre teoria e pr?tica. Para melhor interpreta??o e atribuir significados aos fen?menos analisados, fizemos op??o por uma abordagem qualitativa. Os instrumentos utilizados para coleta de dados foram question?rios com perguntas abertas que tiveram como alvo os alunos egressos do Curso Integrado de T?cnico em Agropecu?ria (CITA), do ano de 2010. Esses instrumentos nos possibilitaram identificar algumas discrep?ncias em rela??o ? articula??o entre escola, est?gio e mundo do trabalho, as quais v?m comprometendo a fun??o do T?cnico em Agropecu?ria na sua ?rea de inser??o. ? importante registrar que al?m desses aspectos, procuramos elencar leis e decretos espec?ficos que influenciaram o desenvolvimento dessa atividade no Brasil. Buscamos, tamb?m, abordar a pr?tica do est?gio numa perspectiva de aproxima??o entre ensino proped?utico e t?cnico, entendidos como capazes de potencializar ao educando uma forma??o para enfrentamento das incertezas do mundo do trabalho.
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Chris Marker e as barricadas da memória: comentários em torno de \'Le fond de l\'air est rouge\' / Chris Marker e as barricadas da memória: comentários em torno de \'Le fond de l\'air est rouge\'Leonel, Nicolau Bruno de Almeida 10 November 2010 (has links)
Esta pesquisa busca, tendo como eixo principal Chris Marker e o filme Le fond de lair est rouge, fazer uma retrospectiva histórica dos principais debates na experiência do cinema-militante francês. Com um caráter introdutório e a partir daí construir alguns apontamentos iniciais para uma interpretação crítica do filme. Através desta aventura político-cinematográfica comentar um fragmento do que se oculta atrás das barricadas da memória. / This research aims, having as an leit-motif Chris Marker and the film Le fond de l\'air est rouge, making a historical retrospective of the major debates on the experience of French militant cinema, introductory in nature and serving as first notes to a critical interpretation of the film. Through this cinematics and politics adventure it trys to make a comment on a fragment of what is hidden behind the barricades of memory.
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Pathologie moléculaire de l’α-synucléine : relations potentielles avec les maladies à prion / Alpha-synuclein molecular pathology : potential relationship with prion diseasesBoyer-Mougenot, Anne-Laure 13 April 2011 (has links)
Les similitudes entre les mécanismes neurotoxiques responsables des encéphalopathies spongiformes Transmissibles (EST) et des synucléinoapthies, ainsi que la présence concomitante des formes pathologiques de la protéine prion et de l’α-synucléine au sein d’une même maladie neurodégénérative sont deux observations qui nous ont conduits à étudier les relations existant potentiellement entre les altérations moléculaires de l’α-synucléine et les maladies à prion. Après avoir développé des anticorps monoclonaux en immunisant avec de l’α-synucléine recombinante humaine des souris n’exprimant pas de façon endogène cet immunogène, nous avons caractérisé les altérations moléculaires de l’α-synucléine apparaissant conjointement à une symptomatologie motrice sévère lors du vieillissement de souris transgéniques (TgM83) surexprimant l’α-synucléine humaine mutée en A53T. Les essais d’inoculation intracérébrale de souris TgM83 par différentes souches de prion ont mis en évidence que la transmission de l’encéphalopathie spongiforme bovine de type H permet de déclencher chez ces animaux une maladie à prion de façon concomitante au développement d’altérations moléculaires de l’α-synucléine. Enfin, l’importante accélération de la pathologie liée a l’α-synucléine observée chez des souris TgM83 ayant été inoculées par des tissus contenant des formes altérées de l’α-synucléine, constitue un résultat soutenant le fait que la pathologie liée a l’α-synucléine serait capable de se propager expérimentalement de proche en proche, comme la protéine prion pathologique au cours des EST / The overlap of neurotoxic mecanisms involved in prion diseases and synucleinopathies, and the concomitant detection of pathological forms of prion and α-synuclein in a same neurodegenerative disease, raise questions about the existence of potential relationship between α‐synuclein molecular alteration and prion diseases. First, we developed monoclonal antibodies by immunizing mice presenting a spontaneous deletion of the α-synuclein gene with human recombinant α‐synuclein. Then, we characterized the molecular alterations appearing jointly to clinical signs during the aging of a transgenic mouse model of synucleinopathies (TgM83), overexpressing human A53T α‐synuclein. Then, an approach routinely done in the field of prion was used to trigger a synucleinopathy alongside a prion disease. For this purpose, TgM83 mice were inoculated intracerebrally by three different prion strains : transmission of H-type bovine spongiform encephalopathy allows the onset of a prion disease concomitantly to the α‐synuclein pathology developed by the TgM83 mouse model. Finally, intracerebral inoculation of TgM83 mice with brain homogenates from symptomatic mice affected by a synucleinopathy triggers an important acceleration of the α‐synuclein pathology, resulting in the early onset of motor clinical signs associated with molecular alterations of α-synuclein. These data suggest that α-synuclein alterations can be experimentally transmitted from one mouse to another, supporting the idea that, far from being confined to the transmissible spongiform encephalopathies, the « prion-like » propagation of misfolded neuronal proteins might occur in synucleinopathies
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