Dissertations / Theses: 'RNP granule'

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Pushpalatha, Kavya Vinayan. "Remodelage des condensats RNP neuronaux au cours du vieillissement chez la drosophile." Electronic Thesis or Diss., Université Côte d'Azur, 2021. http://theses.univ-cotedazur.fr/2021COAZ6007.

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Dans la cellule, les molécules d’ARN s’assemblent avec des protéines de liaison aux ARNs pour former des assemblages macromoléculaires très dynamiques appelés granules ribonucléoprotéiques (RNP). Ces assemblages régulent l’expression génique en contrôlant le transport, la stabilité et/ou la traduction des ARNs associés. Des travaux réalisés in vitro ont montré que la formation et la composition des granules RNP reposent sur l’établissement de réseaux denses d’interactions établis entre protéines et ARN, ainsi que sur leur stoechiométrie. Comment les propriétés des granules RNP sont régulées en contexte physiologique, et en particulier lors du vieillissement, est cependant actuellement peu connu. Mon projet de thèse visait à répondre à cette question par une étude in vivo des granules RNP présents dans les cellules neuronales du cerveau de drosophile.A cette fin, j’ai analysé dans des cerveaux d’âge croissant des granules RNP caractérisés par la présence de la protéine de liaison aux ARNs Imp/ZBP1 et de la DEAD-box hélicase Me31B/DDX6. Mes travaux ont révélé une augmentation progressive de la condensation de Imp et Me31B en larges granules au cours du vieillissement. Ces granules sont dynamiques et ne co-localisent pas avec des marqueurs d’agrégation, suggérant qu’ils ne correspondent pas à des agrégats protéiques statiques. Remarquablement, la condensation de Imp et Me31B est associée à la perte des granules Me31B+ Imp- observées dans les cerveaux jeunes, et à la coalescence de Me31B et Imp pour former des granules uniques Me31B+ Imp+. De plus, ce processus est accompagné d’une inhibition spécifique de la traduction des ARNms associés aux granules, parmi lesquels profilin. Par une analyse fonctionnelle, j’ai mis en évidence qu’une modification de la concentration en Me31B est responsable de la condensation de Me31B dans les cerveaux âgés. Alors qu’une augmentation de la quantité de Me31B est observée au cours du vieillissement, enlever une copie de me31B supprime la condensation age-dépendante de ce composant. Étant donné que la condensation de Imp n’est que partiellement affectée dans ce contexte, j’ai réalisé un crible génétique afin d’identifier des régulateurs de ce processus. Ceci m’a permis de montrer que l’activité de la kinase PKA est essentielle d’une part à la condensation de Imp chez les drosophiles âgées, et d’autre part à la répression traductionnelle des ARNms associés aux granules.En conclusion, mon travail a montré pour la première fois que les propriétés des granules RNP neuronaux sont modifiées au cours du vieillissement, un phénomène qui ne reflète pas une altération générale de l’homéostasie des ARNs, mais plutôt une modulation spécifique de la concentration en composants RNP combinée à l’activité de kinase conservée. Ces résultats démontrent comment les systèmes biologiques peuvent moduler des paramètres clés initialement identifiés dans des contextes in vitro, et ouvrent de nouvelles perspectives dans le domaine de la régulation de l’expression génique au cours du vieillissement
Nascent mRNAs complex with RNA binding proteins (RBPs) to form highly dynamic, phase-separated organelles termed ribonucleoprotein (RNP) granules. These macromolecular assemblies can regulate gene expression by controlling the transport, decay and/or translation of associated RNA molecules. As mostly shown in vitro, RNP granule assembly and function rely on the interaction networks established by individual components and on their stoichiometry. To date, how the properties of constitutive RNP granules are regulated in different physiological context is unclear. In particular, the impact of physiological aging is unclear. My PhD project aimed at addressing this question by analyzing in vivo in long-lived neuronal cells the properties of RNP granules. To this end, I have analysed in flies of increasing age RNP granules characterized by the presence of the conserved RBP Imp/ZBP1 and DEAD-box RNA helicase Me31B/DDX6. Strikingly, a progressive increase in the condensation of Imp and Me31B into granules was observed upon aging. The large granules observed in aged flies were dynamic, contained profilin mRNA, and did not colocalize with Ubiquitin or aggregation markers, suggesting that they do not correspond to static protein aggregates. Increased condensation also associated with the loss of Me31B+ Imp- granules observed in young brains and the collapse of RNP component into a unique class of Me31B+ Imp+ granule. Furthermore, it was accompanied by a specific inhibition of the translation of granule-associated mRNAs, among which the Imp RNA target profilin. Through functional analysis, I uncovered that changes in Me31B stoichiometry trigger Me31B condensation in aged flies. While an increase in Me31B protein levels was observed upon aging, decreasing the dosage of Me31B suppressed its age-dependent condensation. As Imp condensation was only partially suppressed in this context, I performed a selective screen to identify regulators of this process. This revealed that downregulating PKA activity by different genetic means both drastically reduced Imp recruitment and prevented the age-dependent translational repression of granule-associated mRNAs. Taken together, my work thus showed for the first time in vivo that the properties of neuronal RNP granules change upon aging, a phenomenon that does not reflect general alterations in RNA homeostasis but rather specific modulation of RNP component stoichiometry and kinase activity. These results demonstrate how biological systems can modulate key parameters initially defined based on in vitro framework, and also open new perspectives in the field of age-dependent regulation of gene expression

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Vijayakumar, Jeshlee Cyril. "Rôle du domaine de type prion de Imp dans la régulation des granules RNP neuronaux." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4099/document.

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Les ARNms des cellules eucaryotes sont liés à des protéines de liaison aux ARNs (RBPs) et empaquetés au sein d’assemblages macro-moléculaires appelés granules RNP. Dans les cellules neuronales, les granules RNP de transport sont impliqués dans le transport d’ARNms spécifiques jusqu’aux axones et dendrites, ainsi que dans leur traduction locale en réponse à des signaux externes. Bien que peu de choses soient connues sur l’assemblage et la régulation de ces granules in vivo, des résultats récents ont indiqué que la présence de domaines de type prion (PLDs) dans les RBPs facilite les interactions protéines-protéines et protéines-ARN, favorisant ainsi la condensation de complexes solubles en granules RNP. La RBP conservée Imp est un composant central de granules RNP qui sont transportés dans les axones lors du remodelage neuronal chez la drosophile. De plus, la fonction de Imp est nécessaire au remodelage des axones lors de la maturation du système nerveux de drosophile. Une analyse de la séquence de la protéine Imp a révélé qu’en plus de quatre domaines de liaison aux ARNs, Imp contient un domaine C-terminal désordonné enrichi en Glutamines et Serines, deux propriétés caractéristiques des domaines PLDs. Lors de ma thèse, j’ai étudié la fonction de ce PLD dans le contexte de l’assemblage et du transport des granules RNP. J’ai observé en culture de cellules que les granules Imp s’assemblent en absence de PLD, bien que leur nombre et leur taille soient augmentés. Des protéines présentant une séquence PLD mélangée, au contraire, s’accumulent dans des granules au nombre et à la taille normale, indiquant que l’état désordonné de ce domaine, et non sa séquence primaire, est essentiel à l’homéostasie des granules. De plus, des expériences de FRAP réalisées en culture de cellule et in vivo ont révélé que le domaine PLD de Imp favorise la dynamique des granules. In vivo, ce domaine est nécessaire et suffisant à l’accumulation axonale de Imp. Comme montré par une analyse en temps réel, l’absence de domaine PLD aboutit également à une diminution du nombre de granules axonaux motiles. Fonctionnellement, le domaine PLD de Imp est essentiel au remodelage neuronal car des protéines sans ce domaine ne sont pas capables de supprimer les défauts de repousse axonale observés après inactivation de imp. Enfin, la génération d’un variant de Imp dans lequel le domaine PLD a été déplacé en N-terminus a montré que les fonctions du PLD dans le transport des granules et dans leur assemblage sont découplées, et que la modulation des propriétés des granules Imp médiée par le domaine PLD n’est pas nécessaire au remodelage neuronal in vivo. En conclusion, mes résultats ont montré que le domaine PLD de Imp n’est pas nécessaire à l’assemblage des granules RNP Imp, mais régule leur nombre et leur dynamique. De plus, mon travail a mis en évidence une fonction inattendue pour un domaine PLD dans le transport axonal et le remodelage des neurones lors de la maturation du système nerveux
Eukaryotic mRNAs are bound by RNA Binding Proteins (RBP) and packaged into diverse range of macromolecular assemblies named RNP granules. In neurons, transport RNP granules are implicated in the transport of specific mRNAs to axons or dendrites, and in their local translation in response to external cues. Although little is known about the assembly and regulation of these granules in vivo, growing evidence indicates that the presence of Prion Like domains (PLD) within RBPs favours multivalent protein–protein and protein-RNA interactions, promoting the transition of soluble complexes into RNP granules. The conserved RBP Imp is as a core component of RNP granules that are actively transported to axons upon neuronal remodelling in Drosophila. Furthermore, Imp function was shown to be required for axonal remodelling during Drosophila nervous system maturation. Analyses of the domain architecture of the Imp protein revealed that, in addition to four RNA binding domains (RBD), Imp contains a Cterminal domain showing a striking enrichment in Glutamines and Serines, which is one of the characteristics of a PLD. During my PhD, I explored the function of the PLD in the context of granule assembly and transport. In cultured cells, I observed that Imp granules assembled in the absence of the PLD, however their number and size were increased. Proteins with scrambled PLD sequence accumulated in granules of normal size and number, implying that the degree of disorder of this domain, and not its sequence, is essential for granule homeostasis. Moreover, FRAP experiments, performed on cultured cells and in vivo, revealed that Imp PLD is important to maintain the turnover of these granules. In vivo, this domain is both necessary and sufficient for efficient transport of Imp granules to axons. These defects are associated with a reduction on the number of motile granules in axons. Furthermore, mutant forms lacking the PLD do not rescue the axon remodelling defects observed upon imp loss of function. Finally, a swapping experiment in which I moved Imp PLD from the C-terminus to the N-terminus of the protein revealed that the functions of Imp PLD in granule transport and homeostasis are uncoupled, and that PLD-dependent modulation of Imp granule properties is dispensable in vivo. Together, my results show that Imp PLD of is not required for the assembly of RNP granules, but rather regulates granule number and dynamics. Furthermore, my work uncovered an unexpected in vivo function for a PLD in axonal transport and remodelling during nervous system maturation

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Oh, Seong-Wook. "Functional Analysis of RIG-I and RNP Complexes in the Antiviral Interferon System." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215973.

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Cid, Samper Fernando 1991. "Computational approaches to characterize RNP granules." Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/668449.

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Ribonucleoprotein granules (RNP granules) are liquid-liquid phase separated complexes composed mainly by proteins and RNA. They are responsible of many processes involved in RNA regulation. Alterations in the dynamics of these proteinRNA complexes are associated with the appearance of several neurodegenerative disorders such as Amyotrophic Lateral Sclerosis ALS or Fragile X Tremor Ataxia Syndrome FXTAS. Yet, many aspects of their organization as well as the specific roles of the RNA on the formation and function of these complexes are still unknown. In order to study RNP granules structure and formation, we integrated several state of the art high-throughput datasets. This includes protein and RNA composition obtained from RNP pull-downs, protein-RNA interaction data from eCLIP experiments and transcriptome-wide secondary structure information (produced by PARS). We used network analysis and clustering algorithms to understand the fundamental properties of granule RNAs. By integrating these properties, we produced a model to identify scaffolding RNA. Scaffolding RNAs are able to recruit many protein components into RNP granules. We found that the main protein components of stress granules (a kind of RNP granules) are connected through protein-RNA interactions. We also analyzed the contribution of RNA-RNA interactions and RNA post-transcriptional modifications on the granule internal organization. We applied these findings to understand the biochemical pathophysiology of FXTAS disease, employing as well some novel experimental data. In FXTAS, a mutation on the FMR1 gene produces a 5´microsatellite repetition that enhances its scaffolding ability. This mutated mRNA is able to sequester some important proteins into nuclear RNP granules, such as TRA2A (i.e. a splicing factor), impeding their normal function and therefore producing some symptoms associated with the progress of the disease. The better understanding of the principles governing granules formation and structure will enable to develop novel therapies (e.g. aptamers) to mitigate the development of several neurodegenerative diseases.
Los gránulos ribonucleoproteicos (gránulos RNP, por sus siglas en inglés) son complejos producidos mediante separación líquido-líquido y están constituidos principalmente por proteínas y ARN. Son responsables de numerosos procesos involucrados con la regulación del ARN. Alteraciones en la dinámica de estos complejos de proteínas y ARN están asociadas con la aparición de diversas enfermedades neurodegenerativas como el ELA o FXTAS. Sin embargo, todavía se desconocen muchos aspectos relativos a su organización interna así como las contribuciones específicas del RNA en la formación y funcionamiento de estos complejos. A fin de estudiar la estructura y formación de los gránulos RNP, hemos integrado varias bases de datos de alto rendimiento de reciente aparición. Esto incluye datos sobre la composición proteica y en ARN de los RNP, sobre la interacción de proteínas y ARN extraída de experimentos de eCLIP y sobre la estructura secundaria del transcriptoma (producida mediante PARS). Todos estos datos han sido procesados para comprender las propiedades fundamentales de los ARNs que integran los gránulos, mediante el empleo de métodos computacionales como el análisis de redes o algoritmos de agrupamiento. De esta manera, hemos producido un modelo que integra varias de estas propiedades e identifica candidatos denominados ARNs de andamiaje. Definimos ARNs de andamiaje como moléculas de ARN con una alta propensión a formar gránulos y reclutar un gran número de componentes proteicos a los gránulos RNP. También hemos encontrado que las interacciones proteína-ARN conectan los principales componentes proteicos de consenso de los gránulos de estrés (un tipo específico de gránulos RNP). También hemos estudiado la contribución de las interacciones ARN-ARN y las modificaciones post-transcriptionales del RNA en la organización interna del gránulo. Hemos aplicado estos resultados para la comprensión de la fisiopatología molecular de FXTAS, empleando también algunos datos experimentales originales. En FXTAS, una mutación en el gen FMR1 produce una repetición de microsatélite en 5´ que incrementa su capacidad como ARN de andamiaje. Este mARN mutado es capaz de secuestrar algunas proteínas importantes como TRA2A (un factor de ayuste alternativo) en gránulos RNP nucleares, impidiendo su normal funcionamiento y por consiguiente produciendo algunos síntomas asociados con el progreso de la enfermedad. Una mejor comprensión de los principios que gobiernan la formación y estructura de los gránulos puede permitir desarrollar nuevas terapias (ej: aptámeros) para mitigar el desarrollo de diversas enfermedades neurodegenerativas.

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Agostini, Federico 1985. "Predictions of RNA-binding ability and aggregation propensity of proteins." Doctoral thesis, Universitat Pompeu Fabra, 2014. http://hdl.handle.net/10803/318159.

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RNA-binding proteins (RBPs) control the fate of a multitude of coding and non-coding transcripts. Formation of ribonucleoprotein (RNP) complexes fine-tunes regulation of post-transcriptional events and influences gene expression. Recently, it has been observed that non-canonical proteins with RNA-binding ability are enriched in structurally disordered and low-complexity regions that are generally involved in functional and dysfunctional associations. Therefore, it is possible that interactions with RNA protect unstructured protein domains from aberrant associations or aggregation. Nevertheless, the mechanisms that prevent protein aggregation and the role of RNA in such processes are not well understood. In this work, I will describe algorithms that I have developed to predict protein solubility and to estimate the ability of proteins and transcripts to interact. I will illustrate applications of computational methods and show how they can be integrated with high throughput approaches. The overarching goal of my work is to provide experimentalists with tools that facilitate the investigation of regulatory mechanisms controlling protein homeostasis.
Las proteínas de unión de ARN son responsables de controlar el destino de una multitud de transcriptos codificantes y no codificantes. De hecho, la formación de complejos de ribonucleoproteínas (RNP) afina la regulación de una serie de eventos post-transcripcionales e influye en la expresión génica. Recientemente, se ha observado que las proteínas con capacidad no canónica de unión al ARN se enriquecen en las regiones estructuralmente desordenadas y de baja complejidad, que son las que participan generalmente en asociaciones funcionales y disfuncionales. Por lo tanto, es posible que interactuar con el ARN pudiera ser una manera de proteger las proteínas no estructuradas de asociaciones aberrantes o de agregación. Sin embargo, los mecanismos que impiden la agregación de proteínas y la función del ARN en tales procesos no están bien descritas. En este trabajo, se describen los me ́todos que he desarrollado para predecir la solubilidad de proteínas y para estimar la capacidad de transcriptos y proteínas de interactuar. De otra parte, voy a ilustrar sus aplicaciones y explicar como los métodos de bajo rendimiento han evolucionado a un mayor rendimiento. El objetivo final es proporcionar instrumentos a los investigadores experimentales que se pueden utilizar para facilitar la investigación de los mecanismos reguladores que controlan la homeostasis molecular.

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Formicola, Nadia. "Remodelage des granules ARN en réponse à l’activité neuronale." Electronic Thesis or Diss., Université Côte d'Azur (ComUE), 2019. http://theses.univ-cotedazur.fr/2019AZUR6008.

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Une des questions les plus fascinantes – et les plus ouvertes – en neuroscience est de comprendre comment les cellules neuronales contribuent à la formation, le maintien puis le rappel des souvenirs. Des travaux antérieurs ont montré que la formation de la mémoire à long-terme (MLT) requiert la synthèse de novo de protéines, impliquant non seulement la traduction d’ARNs nouvellement transcrits, mais aussi la traduction locale, induite par l’expérience, d’ARNms latents transportés et stockés dans les synapses. En vue de leur transport et du contrôle de leur traduction, les ARNms sont empaquetés avec des protéines de liaison aux ARNs (RBP), qui sont majoritairement des répresseurs de traduction, dans des granules ribonucléoprotéiques (RNP). La manière dont les granules RNP neuronaux sont remodelés en réponse à l’activité neuronale pour lever la répression traductionelle des ARNms est pour l’instant peu claire. En outre, l’impact fonctionnel d’un tel remodelage sur l’établissement de la MLT reste à démontrer in vivo. L’objectif de mon doctorat était 1) d’étudier les mécanismes in vivo qui sous-tendent le remodelage des granules RNP neuronaux ; 2) de tester l’hypothèse que les granules RNP pourraient être impliqués dans les mécanismes de renforcement de la MLT en régulant l’expression génétique. Dans cette optique, j’ai utilisé comme modèle des granules RNP contenant la RBP conservée Imp chez la drosophile. Tout d’abord, j’ai étudié l’impact de l’activité neuronale sur les propriétés des granules RNP Imp, en traitant des explants de cerveau soit avec du KCl, soit avec le neuromodulateur Tyramine. Dans les deux cas, un désassemblage des granules RNP Imp - caractérisé par une dé-granulation à la fois de Imp et d’autres composants – est observé. Le désassemblage des granules RNP est réversible après retrait de la tyramine, et n’a pas été observé dans les neurones hyperpolarisés. Il ne dépend pas strictement du domaine de type prion qui se trouve à l’extrémité carboxy-terminale de Imp, un domaine connu pour être impliqué dans l’homéostasie des granules RNP. De plus, mes données suggèrent que ce désassemblage soit lié à une augmentation de la traduction des ARNms associés, ce qui est cohérent avec un modèle dans lequel le remodelage des granules RNP induit par l’activité des neurones induit une dé-répression de la traduction. Ensuite, j’ai recherché les mécanismes contrôlant le remodelage des granules RNP. Un candidat pour cette régulation était CamkII, une kinase conservée activée par le calcium, et identifiée comme partenaire de Imp dans une analyse d’immunoprécipitation-spectrométrie de masse. Au cours de mon doctorat, j’ai pu valider l’intéraction Imp-CamkII et montrer qu’elle n’est pas médiée par l’ARN, mais dépend de l’activité de CamkII. De plus, j’ai montré qu’inhiber l’activité de CamkII empêche le désassemblage des granules RNP Imp observé lors de l’activation neuronale, suggérant que CamkII pourrait être impliquée dans le remodelage des granules RNP Imp induit par l’activité neuronale. Ces résutats sont particulièrement intéressants dans le contexte de l’établissement de la MLT, car CamkII est depuis longtemps reconnue comme y étant essentielle. Plus encore, nous avons récemment démontré chez la drosophile qu’inactiver la fonction de Imp dans une population de neurones du cerveau central impliquée dans l’apprentissage et la mémoire – les neurones du Mushroom Body – altère radicalement la MLT. En conclusion, mes résultats sont cohérents avec un modèle où le remodelage des granules RNP Imp en réponse à l’activation neuronale dépend de CamkII, et pourrait contribuer à la formation de la MLT in vivo
One of the most fascinating – and still open – questions in neuroscience is how neuronal cells can form, store and then recall memories. Previous work has shown that Long-term memory (LTM) formation requires de novo protein synthesis, involving not only translation of newly transcribed RNAs, but also local, experience-induced translation of quiescent mRNAs carried and stored at synapses. For their transport and translational control, mRNAs are packaged with regulatory RNA binding proteins (RBPs), mainly translational repressors, into ribonucleoprotein (RNP) granules. To date, how neuronal RNP granules are remodelled in response to neuronal activity to relieve translation repression of mRNAs is unclear. Furthermore, the functional impact of such a remodelling in the establishment of long-term memories remains to be demonstrated in vivo. The objective of my PhD was to 1) investigate the in vivo mechanisms underlying activity-dependent remodelling of neuronal RNP granules; 2) test the hypothesis that RNPs could be involved in LTM-underlying mechanisms by regulating gene expression. To this end, I used as paradigm RNPs containing the conserved RBP Imp in Drosophila. First, I studied the impact of neuronal activity on Imp RNP properties by treating Drosophila brain explants with either KCl or the tyramine neuropeptide. In both cases, a disassembly of Imp RNPs was observed, characterized by a loss of both Imp and other RNP-component granular patterns, and a de-clustering of RNP-associated mRNA molecules. RNP disassembly could be reverted upon Tyramine withdrawal and was not observed in hyperpolarized neurons. Furthermore, my data suggest that RNP-disassembly is linked to increased translation of associated mRNAs, consistent with a model in which activity-induced RNP remodelling would lead to translational de-repression. Second, I investigated the mechanisms controlling RNP remodelling. A candidate regulator was CamkII, a conserved Ca2+ -activated kinase identified as a partner of Imp in an IP-Mass Spectrometry analysis. During my PhD, I could validate the Imp-CamkII interaction and showed that it is not mediated by RNA but depends on CamkII activity. Furthermore, I showed that inactivating CamkII function prevents the disassembly of Imp RNPs observed upon neuronal activation of brain explants, suggesting that CamkII may be involved in the activity-dependent remodelling of Imp RNP granules. These results are particularly interesting in the context of establishment of LTM, as CamkII has long been recognized as essential for LTM. Moreover, we recently showed in Drosophila that interfering with Imp function in a population of CNS neurons involved in learning and memory – the Mushroom Body γ neurons -, dramatically impairs LTM and that this effect relies on Imp C-terminal Prion-like domain, a domain known to be involved in RNP homeostasis. Altogether, my thesis work suggests a model where CamkII-dependent remodelling of Imp RNPs in response to neuronal activation might underlie LTM formation in vivo

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Al-Sailawi, Majid. "Investigating RNA granules formation during caliciviruses infection." Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/809289/.

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Human norovirus (HuNV) is a member of the calicivirus family and is a major cause of viral gastroenteritis worldwide. Due to the absence of a suitable cell culture system, HuNoV replication mechanisms are poorly understood, but two animal caliciviruses, Feline calicivirus (FCV) and Murine Norovirus (MNV) provide models to increase our understanding of norovirus biology. Unlike cellular mRNAs, the calicivirus RNA genome does not possess a 5' cap structure but instead has a 13–15 kDa viral protein, genome linked (VPg) directing translation, hijacking the host protein synthesis machinery. The viral life cycle requires separated events occurring at different times since viral transcripts are used as the template both for translation (mRNA) and replication (genomic RNA). Therefore mechanisms are required to control the viral RNA fate. In eukaryotes, during stress conditions, mRNAs can be stored in subcellular compartments such as stress granules to stall their translation or in processing bodies to be degraded. Recent evidence indicates that these compartments also play an important role during the viral life cycle. Therefore, using immunofluorescence microscopy we set out to investigate how FCV and MNV infection regulate the formation of G3BP1- and PABP-1-containing stress granules and DCP-1-containing processing bodies to address whether these cytoplasmic granules could play a role during the viral life cycle. We have now shown that FCV has the ability to prevent stress granules formation during infection and that this is important for replication in CRFK and FEA cells. Using FCV-free supernatant from infected CRFK cells and immunofluorescence microscopy, we have also shown that during infection, the formation of stress granules is induced in a paracrine manner in uninfected cells via a messenger molecule released from infected cells. We hypothesize that this could reflect a new antiviral role for stress granules. Furthermore, MNV and FCV infection also led to the disruption of processing-bodies assembly. Overall, this study revealed that caliciviruses modulate the RNA granules during infection and that this could be part of viral mechanism to counteract the antiviral response.

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Shah, Khyati H. "REGULATION, COMPOSITION AND FUNCTIONS OF RNP GRANULES IN QUIESCENT CELLS OF SACCHAROMYCES CEREVISIAE." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1417541239.

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Lockwood, Donovan Blair. "TDP-43 Modulation of PABP Positive, RNA Stress Granule Formation during Oxidative Stress." Thesis, The University of Arizona, 2015. http://hdl.handle.net/10150/579304.

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RNA dysregulation is a recently recognized disease mechanism in amyotrophic lateral sclerosis (ALS). ALS is a neurodegenerative disease characterized by muscle atrophy and death of both upper and lower motor neurons. A key feature of the disease is the mislocalization of the RNA binding protein TDP-43 and formation of TDP-43 containing cytoplasmic aggregates in motor neurons and surrounding glia. TDP-43 is known to associate with stress granules, and recent studies in mammalian cell culture have indicated that pathological TDP-43 aggregates may arise from RNA stress granules following prolonged stress. We set out to test this hypothesis by investigating the interaction between PolyA Binding Protein (PABP), a known core RNA stress granule component, and TDP-43. Here we show that PABP colocalizes with TDP-43 in a variant dependent manner. Given that the highest risk factor for ALS is aging, an attractive model is that age-related oxidative stress triggers formation of toxic cytoplasmic aggregates from TDP-43 containing stress granules. We have therefore begun investigations using a time course, and live imaging of RNA stress granules under oxidative stress to determine if this leads to an altered RNA stress granule dynamics in cultured motor neurons. These studies will yield a better understanding of the mechanisms that lead to the toxic cytoplasmic aggregates in cases of ALS.

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Schreier, Juliane [Verfasser]. "Role of PKCε in RNA granule formation and protein translation / Juliane Schreier." Berlin : Freie Universität Berlin, 2013. http://d-nb.info/104162090X/34.

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Yatsuzuka, Kenji. "Live-cell imaging of multiple endogenous mRNAs permits the direct observation of RNA granule dynamics." Kyoto University, 2019. http://hdl.handle.net/2433/242400.

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Day, Mandy Dowson. "A study of wheat endosperm development : cell and starch granule numbers and amyloplast DNA and RNA." Thesis, University of Bath, 1987. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379338.

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Pizzinga, Mariavittoria. "Granules of translation factor mRNAs and their potential role in the localisation of the translation machinery to regions of polarised growth." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/granules-of-translation-factor-mrnas-and-their-potential-role-in-the-localisation-of-the-translation-machinery-to-regions-of-polarised-growth(9cb42e69-3c8c-4f10-b79f-ba8261be4430).html.

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The subcellular localisation of mRNA is a widespread mechanism to determine the fate of mRNAs in eukaryotes. Translationally repressed mRNAs localise to P-bodies and stress granules where their decay and storage, respectively, are directed. In a study from the Ashe lab, specific mRNAs were identified to localise, in actively growing S. cerevisiae, to cytoplasmic granules that do not seem to be related to P-bodies or stress granules but appear to be associated with active translation (Lui et al., 2014).It is possible that this might represent a strategy to co-regulate the expression of proteins from the same pathway. In the work of this thesis, microscopy techniques to visualise RNAs in live cells were used to extend the localisation analysis to several mRNAs encoding translation factors. The investigated transcripts were all found to localise to mostly one or two cytoplasmic granules per cell and would sometimes overlap with other transcripts, suggesting that each granule contains a mixture of mRNAs. Granules tend to migrate to the bud tip and may provide the daughter cell with a "start-up kit" of transcripts essential for rapid growth. A similar pattern can be observed in yeast cells growing undergoing filamentous growth, with granules harbouring translation factor transcripts often found in the apical quarter of the elongated cell. Although the mechanism by which the granules form and their protein composition are not yet known, high-throughput genetic screens performed as part of this work offer some insight into factors that might be involved in granule assembly and proteins that partially overlap with the granules. We propose that granules containing translation factor mRNAs might be functioning as a specialised factory for the translation machinery and are possibly being directed to the point in the cell where the rhythm of protein production is highest.

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Bauer, Karl Emory [Verfasser], and Michael [Akademischer Betreuer] Kiebler. "Live microscopy of RNA granule sorting in hippocampal neurons in space and time / Karl Emory Bauer ; Betreuer: Michael Kiebler." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1196529094/34.

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Lau, Pok, and 劉博. "MicroRNAs associated with granulin-epithelin precursor in hepatocellular carcinoma." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206753.

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Hepatocellular carcinoma (HCC) is the major type of liver cancer. In Hong Kong, thousands of deaths are related to this disease every year. Hepatitis B virus (HBV) infection is one of the major risk factors of HCC development. The high prevalence of HBV carriers in Southeast Asia including Hong Kong can account for the particularly high HCC cases in these areas. HCC is often asymptomatic. The diagnosis and treatment are often delayed which lead to inapplicable of surgical resection. Meanwhile, conventional treatment regimes such as systemic chemotherapy were found to have limited responses. Hence, the case mortality rate of HCC is the second highest among all the cancers. Granulin-epithelin Precursor (GEP) is a glycoprotein growth factor which regulates multiple cellular functions. Our group has demonstrated that GEP is over-expressed in more than 70% of HCC cases and GEP expression is positively correlated to tumor malignancy. Our group has also verified that suppression of GEP by monoclonal antibody leads to significant inhibition of HCC growth and reduction of malignancy. Therefore, GEP has the potential to be a novel therapeutic target of HCC. MicroRNAs (miRNAs) are short non-coding RNAs that regulate mRNA translation. Previous studies showed that miRNA dys- regulation is closely associated with HCC progression and the high stability of miRNAs allows them to be cancer biomarkers or therapeutic targets. This project aims to investigate the miRNAs that regulate GEP and their functions in HCC. Potential GEP-regulating miRNAs were identified by literature review and in silico prediction by bioinformatics tools. MiR-615-5p, miR-588, miR-29b, miR-195, and miR-659 were identified as the potential candidates. Quantitative polymerase chain reaction (qPCR) was utilized to examine the miRNAs’ expressions in HCC clinical samples. Only miR-29b and miR-195 were detected and hence they were selected for further study. Our results showed that miR-29b and miR-195 expression levels were significantly decreased in HCC comparing to adjacent non‐tumor tissue (P<0.001) in more than 70% of cases. MiR‐195 and miR‐29b were over‐expressed in Hep3B HCC cell lines by miRNA mimics and GEP protein level was significantly suppressed after miR-29b mimic transfection. The transcript level of GEP was found to be unchanged after the miR‐29b over-expression. This suggests miR‐29b does not regulate GEP protein expression by mRNA degradation. The effects of miR‐195 and miR‐29b on HCC proliferation were also examined. The growths of HCC cells were suppressed notably after over-expression of miR‐195 (P<0.005) and miR‐29b (P<0.005) respectively. In conclusion, miR‐195 and miR‐29b are frequently down-regulated in HCC. MiR‐29b can negatively regulate GEP expression and does not interfere with GEP mRNA level. Furthermore, miR‐195 and miR-29b can function to inhibit HCC cell growth significantly.
published_or_final_version
Surgery
Master
Master of Philosophy

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Eckmann, Christian R., Mark Schmid, Adam P. Kupinski, Britta Jedamzik, Martin Harterink, and Agata Rybarska. "GLS-1, a novel P granule component, modulates a network of conserved RNA regulators to influence germ cell fate decisions." PLOS Genetics, 2009. https://tud.qucosa.de/id/qucosa%3A28993.

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Post-transcriptional regulatory mechanisms are widely used to influence cell fate decisions in germ cells, early embryos, and neurons. Many conserved cytoplasmic RNA regulatory proteins associate with each other and assemble on target mRNAs, forming ribonucleoprotein (RNP) complexes, to control the mRNAs translational output. How these RNA regulatory networks are orchestrated during development to regulate cell fate decisions remains elusive. We addressed this problem by focusing on Caenorhabditis elegans germline development, an exemplar of post-transcriptional control mechanisms. Here, we report the discovery of GLS-1, a new factor required for many aspects of germline development, including the oocyte cell fate in hermaphrodites and germline survival. We find that GLS-1 is a cytoplasmic protein that localizes in germ cells dynamically to germplasm (P) granules. Furthermore, its functions depend on its ability to form a protein complex with the RNA-binding Bicaudal-C ortholog GLD-3, a translational activator and P granule component important for similar germ cell fate decisions. Based on genetic epistasis experiments and in vitro competition experiments, we suggest that GLS-1 releases FBF/Pumilio from GLD-3 repression. This facilitates the sperm-to-oocyte switch, as liberated FBF represses the translation of mRNAs encoding spermatogenesis-promoting factors. Our proposed molecular mechanism is based on the GLS-1 protein acting as a molecular mimic of FBF/Pumilio. Furthermore, we suggest that a maternal GLS-1/GLD-3 complex in early embryos promotes the expression of mRNAs encoding germline survival factors. Our work identifies GLS-1 as a fundamental regulator of germline development. GLS-1 directs germ cell fate decisions by modulating the availability and activity of a single translational network component, GLD-3. Hence, the elucidation of the mechanisms underlying GLS-1 functions provides a new example of how conserved machinery can be developmentally manipulated to influence cell fate decisions and tissue development.

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Eckmann, Christian R., Mark Schmid, Adam P. Kupinski, Britta Jedamzik, Martin Harterink, and Agata Rybarska. "GLS-1, a novel P granule component, modulates a network of conserved RNA regulators to influence germ cell fate decisions." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-184095.

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Post-transcriptional regulatory mechanisms are widely used to influence cell fate decisions in germ cells, early embryos, and neurons. Many conserved cytoplasmic RNA regulatory proteins associate with each other and assemble on target mRNAs, forming ribonucleoprotein (RNP) complexes, to control the mRNAs translational output. How these RNA regulatory networks are orchestrated during development to regulate cell fate decisions remains elusive. We addressed this problem by focusing on Caenorhabditis elegans germline development, an exemplar of post-transcriptional control mechanisms. Here, we report the discovery of GLS-1, a new factor required for many aspects of germline development, including the oocyte cell fate in hermaphrodites and germline survival. We find that GLS-1 is a cytoplasmic protein that localizes in germ cells dynamically to germplasm (P) granules. Furthermore, its functions depend on its ability to form a protein complex with the RNA-binding Bicaudal-C ortholog GLD-3, a translational activator and P granule component important for similar germ cell fate decisions. Based on genetic epistasis experiments and in vitro competition experiments, we suggest that GLS-1 releases FBF/Pumilio from GLD-3 repression. This facilitates the sperm-to-oocyte switch, as liberated FBF represses the translation of mRNAs encoding spermatogenesis-promoting factors. Our proposed molecular mechanism is based on the GLS-1 protein acting as a molecular mimic of FBF/Pumilio. Furthermore, we suggest that a maternal GLS-1/GLD-3 complex in early embryos promotes the expression of mRNAs encoding germline survival factors. Our work identifies GLS-1 as a fundamental regulator of germline development. GLS-1 directs germ cell fate decisions by modulating the availability and activity of a single translational network component, GLD-3. Hence, the elucidation of the mechanisms underlying GLS-1 functions provides a new example of how conserved machinery can be developmentally manipulated to influence cell fate decisions and tissue development.

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Ko, Hae Kyung. "Exploring the Role of FUS Mutants from Stress Granule Incorporation to Nucleopathy in Amyotrophic Lateral Sclerosis: A Dissertation." eScholarship@UMMS, 2009. http://escholarship.umassmed.edu/gsbs_diss/799.

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Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by preferential motor neuron death in the brain and spinal cord. The rapid disease progression results in death due to respiratory failure, typically within 3-5 years after disease onset. While ~90% of cases occur sporadically, remaining 10% of ALS cases show familial inheritance, and the number of genes linked to ALS has increased dramatically over the past decade. FUS/TLS (Fused in Sarcoma/ Translocated to liposarcoma) is a nucleic acid binding protein that may regulate several cellular functions, including RNA splicing, transcription, DNA damage repair and microRNA biogenesis. More than 50 mutations in the FUS gene are linked to 4% of familial ALS, and many of these may disrupt the nuclear localization signal, leading to variable amounts of FUS accumulation in the cytoplasm. However, the mechanism by which FUS mutants cause motor neuron death is still unknown. The studies presented in this dissertation focused on investigating the properties of FUS mutants in the absence and presence of stress conditions. We first examined how ALS-linked FUS mutants behaved in response to imposed stresses in both cell culture and zebrafish models of ALS. We found that FUS mutants were prone to accumulate in stress granules in proportion to their degree of cytoplasmic mislocalization under conditions of oxidative stress, ER stress, and heat shock. However, many FUS missense mutants are retained predominantly in the nucleus, and this suggested the possibility that these mutants might also perturb one or more nuclear functions. In a human cell line expressing FUS variants and in human fibroblasts from an ALS patient, mutant FUS expression was associated with enlarged promyelocytic leukemia nuclear bodies (PML-NBs) under basal condition. Upon oxidative insult with arsenic trioxide (ATO), PML-NBs in control cells increased acutely in size and were turned over within 12-24 h, as expected. However, PML-NBs in FUS mutant cells did not progress through the expected turnover but instead continued to enlarge over 24 h. We also observed a persistent accumulation of the transcriptional repressor Daxx and the 11S proteasome regulator in association with these enlarged PML-NBs. Furthermore, the peptidase activities of the 26S proteasome were decreased in FUS mutant cells without any changes in the expression of proteasome subunits. These results demonstrate that FUS mutant expression may alter cellular stress responses as manifested by (i) accumulation of mutant FUS into stress granules and (ii) inhibition of PML-NB dynamics. These findings suggest a novel nuclear pathology specific to mutant FUS expression that may perturb nuclear homeostasis and thereby contribute to ALS pathogenesis.

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Ko, Hae Kyung. "Exploring the Role of FUS Mutants from Stress Granule Incorporation to Nucleopathy in Amyotrophic Lateral Sclerosis: A Dissertation." eScholarship@UMMS, 2015. https://escholarship.umassmed.edu/gsbs_diss/799.

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Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by preferential motor neuron death in the brain and spinal cord. The rapid disease progression results in death due to respiratory failure, typically within 3-5 years after disease onset. While ~90% of cases occur sporadically, remaining 10% of ALS cases show familial inheritance, and the number of genes linked to ALS has increased dramatically over the past decade. FUS/TLS (Fused in Sarcoma/ Translocated to liposarcoma) is a nucleic acid binding protein that may regulate several cellular functions, including RNA splicing, transcription, DNA damage repair and microRNA biogenesis. More than 50 mutations in the FUS gene are linked to 4% of familial ALS, and many of these may disrupt the nuclear localization signal, leading to variable amounts of FUS accumulation in the cytoplasm. However, the mechanism by which FUS mutants cause motor neuron death is still unknown. The studies presented in this dissertation focused on investigating the properties of FUS mutants in the absence and presence of stress conditions. We first examined how ALS-linked FUS mutants behaved in response to imposed stresses in both cell culture and zebrafish models of ALS. We found that FUS mutants were prone to accumulate in stress granules in proportion to their degree of cytoplasmic mislocalization under conditions of oxidative stress, ER stress, and heat shock. However, many FUS missense mutants are retained predominantly in the nucleus, and this suggested the possibility that these mutants might also perturb one or more nuclear functions. In a human cell line expressing FUS variants and in human fibroblasts from an ALS patient, mutant FUS expression was associated with enlarged promyelocytic leukemia nuclear bodies (PML-NBs) under basal condition. Upon oxidative insult with arsenic trioxide (ATO), PML-NBs in control cells increased acutely in size and were turned over within 12-24 h, as expected. However, PML-NBs in FUS mutant cells did not progress through the expected turnover but instead continued to enlarge over 24 h. We also observed a persistent accumulation of the transcriptional repressor Daxx and the 11S proteasome regulator in association with these enlarged PML-NBs. Furthermore, the peptidase activities of the 26S proteasome were decreased in FUS mutant cells without any changes in the expression of proteasome subunits. These results demonstrate that FUS mutant expression may alter cellular stress responses as manifested by (i) accumulation of mutant FUS into stress granules and (ii) inhibition of PML-NB dynamics. These findings suggest a novel nuclear pathology specific to mutant FUS expression that may perturb nuclear homeostasis and thereby contribute to ALS pathogenesis.

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Chan, On-chim, and 陳安潛. "Characterization of microbial consortia in anaerobic granular sludge: a ribosomal RNA-based molecular approach." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31239924.

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Kuznicki, Kathleen. "The function of the germline rna helicase (GLH) genes in caenorhabditis elegans." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9988682.

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Palud, Amandine. "Liquid-liquid phase separation mediated by low complexity sequence domains promotes stress granule assembly and drives pathological fibrillization." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066560/document.

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Il a été observé que l’altération des fonctions des granules de stress, entités cytoplasmiques non-membranaires composées d’ARN et de protéines liant l’ARN (RBPs), peut conduire au développement de maladies telles que la sclérose latérale amyotrophique, la démence fronto-temporale, la myopathie à inclusions et la maladie de Paget des os. Ces pathologies sont caractérisées par un dépôt cytoplasmique d’inclusions solides enrichies en RBPs et comprenant des fibrilles. Une connexion génétique a été suggérée entre la persistance des granules de stress et l’accumulation de ces inclusions pathologiques dans le cytoplasme des patients. Dans mon manuscrit de thèse, il est mis en évidence le fait que la protéine hnRNPA1, dont les mutations entrainent les maladies mentionnées plus haut, subit une séparation de phases entre deux liquides connue également sous l’appellation « Séparation de Phases Liquide-Liquide » (LLPS) dans des gouttelettes enrichies en protéines. Bien que le domaine composé d’une séquence à faible complexité (Low Complexity sequence Domains ou LCD) soit suffisant pour obtenir cette séparation de phases, les domaines de liaison à l’ARN y contribuent également en présence d’ARN. Cela a permis d’envisager l’existence de plusieurs mécanismes intervenant dans la régulation de l’assemblage de ces granules. Un autre résultat a mis en exergue le fait que la formation de fibrilles n’est pas une obligation pour permettre la séparation de phases mais que les gouttelettes, enrichies en protéines, entrainent, par ailleurs, une augmentation de la formation de ces fibrilles. La séparation de phases liquide-liquide induite par le domaine composé d’une séquence à faible complexité semble contribuer à l’assemblage des granules de stress et à leurs propriétés liquides. Finalement, cette étude propose d’établir une réelle corrélation entre la formation des granules de stress qui deviennent persistants et l’accumulation d’inclusions pathologiques dans le cytoplasme des patients
Stress granules are membrane-less organelles composed of RNA-binding proteins (RBPs) and RNA. Functional impairment of stress granules has been implicated in amyotrophic lateral sclerosis, inclusion body myopathy, Paget’s disease of bone and frontotemporal dementia; these diseases are characterized by solid, fibrillar, cytoplasmic inclusions that are rich in RNA binding proteins (RBPs). Genetic evidence suggests a link between persistent stress granules and the accumulation of pathological inclusions. In this thesis manuscript, I demonstrate that the disease-related RBP hnRNPA1 undergoes liquid-liquid phase separation (LLPS) into protein-rich droplets mediated by a low complexity sequence domain (LCD). While the LCD of hnRNPA1 is sufficient to mediate LLPS, the folded RNA recognition motifs contribute to LLPS in the presence of RNA, potentially giving rise to several mechanisms for regulating assembly of stress granules. Importantly, while not required for LLPS, fibrillization is enhanced in protein-rich droplets. I suggest that LCD-mediated LLPS contributes to the assembly of stress granules and their liquid properties, and provides a mechanistic link between persistent stress granules and fibrillar protein pathology in disease

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Chitiprolu, Maneka. "Novel Regulatory Mechanisms of Autophagy in Human Disease: Implications for the Development of Therapeutic Strategies." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38441.

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The dysfunction of autophagy pathways has been linked to the development and progression of numerous human diseases, in particular neurological disorders and cancer. Investigating these pathological autophagy mechanisms is essential to gain insights into the underlying disease mechanisms, identify novel biomarkers, and develop targeted therapies. In this thesis, I present three manuscripts that investigate the regulatory mechanisms of autophagy machinery in human diseases. In the first manuscript (Chitiprolu et al., 2018), we investigated the mechanism of p62-mediated selective autophagic clearance of RNA stress granules implicated in Amyotrophic Lateral Sclerosis (ALS). Repeat expansions in C9ORF72, the major cause of ALS, reduce C9ORF72 levels but how this impacts stress granules is uncertain. By employing mass spectrometry, high resolution imaging and biochemical assays, we demonstrated that the autophagy receptor p62 associates with C9ORF72 to eliminate stress granules by autophagy. This requires p62 to associate with proteins that are symmetrically methylated on arginines. Patients with C9ORF72 repeat expansions accumulate symmetric arginine dimethylated proteins which co-localize with p62. This suggests that C9ORF72 initiates a cascade of ALS-linked proteins (C9ORF72, p62, SMN, FUS) to recognize stress granules for degradation by autophagy and hallmarks of a defect in this process are observable in ALS patients. The second manuscript (Guo, Chitiprolu et al., 2014) describes the mechanism by which autophagy degrades retrotransposon RNA from both long and short interspersed elements, thereby preventing new retrotransposon insertions into the genome. By employing quantitative imaging tools, we demonstrated that retrotransposon RNA localizes to RNA granules that are selectively degraded by the autophagy receptors NDP52 and p62. Mice lacking a copy of Atg6/Beclin1, a gene critical for autophagy, also accumulate both retrotransposon RNA and genomic insertions. This suggests a mechanism for the increased tumorigenesis upon autophagy inhibition and therefore a role for autophagy in tempering evolutionary change. Finally, the third manuscript (Guo, Chitiprolu et al., 2017) examines the intersection of autophagy machinery with exosome release and function in cancer metastasis. By employing dynamic light scattering, Nanosight particle tracking, electron microscopy, super-resolution imaging and Western blotting, we robustly quantified exosome identity and purity in multiple cell lines. We demonstrated that exosome production is strongly reduced in cells lacking Atg5 and Atg16L1, but this is independent of Atg7 and canonical autophagy. The effect of Atg5 on exosome production promotes the migration and in vivo metastasis of orthotopic breast cancer cells. These findings delineate autophagy-independent pathways by which autophagy-related genes can contribute to metastasis. Taken together, data presented in the three manuscripts highlight the molecular mechanisms of autophagy core machinery proteins and selective receptors such as Atg5, p62 and NDP52, in the pathogenesis of cancer and neurodegeneration. In these diseases characterized by mutations in autophagy pathways, the mechanisms we uncover provide insights into their causes and serve as potential therapeutic targets.

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Twyffels, Laure. "Nucleo-cytoplasmic transport of TIS11 proteins and stress granule assembly: two potential new roles for Transportins." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209423.

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The nucleo-cytoplasmic compartmentalization enables eukaryotic cells to develop sophisticated post-transcriptional regulations of gene expression. However, managing the exchanges of macromolecules between the two compartments also represents a formidable challenge for the cells. Nucleo-cytoplasmic exchanges rely on specialized soluble carriers and take place at nuclear pore complexes that span the nuclear envelope. Active nucleo-cytoplasmic transport of proteins, in particular, is performed mainly by a family of carriers called karyopherins, which includes about twenty members in mammals. Some of them, called importins, recognize nuclear localization signals (NLSs) in their substrates and convey them into the nucleus. Others, called exportins, recognize nuclear export signals (NESs) in their substrates and bring them back to the cytoplasm.

Many RNA-binding proteins (RBPs) shuttle between the nucleus and the cytoplasm, where they can often fulfill different functions. RBPs also frequently localize into specialized microdomains that are not delimited by a membrane but in which specific factors are concentrated. Those include processing bodies and stress granules, which are cytoplasmic foci associated with mRNA decay, storage and translational repression. Post-transcriptional regulations mediated by RBPs can therefore be modulated rapidly and efficiently through changes in the localization of RBPs.

The first part of this work focuses on the subcellular localization and nucleo-cytoplasmic transport of the Drosophila RBP dTIS11. Like its mammalian and yeast homologues, dTIS11 binds AU-rich elements in the 3’UTR of its target mRNAs, and stimulates their rapid deadenylation and decay. Here, we have observed that although dTIS11 appears to be located mostly in the cytoplasm, it is constantly shuttling in and out of the nucleus. We show that the export of dTIS11 from the nucleus depends on the CRM1 exportin and is mediated by a hydrophobic NES that encompasses residues 101 to 113 in dTIS11 sequence. We also identify a cryptic Transportin-dependent PY nuclear localization signal (PY-NLS) in the tandem zinc finger region of dTIS11 and show that it is conserved across the TIS11 protein family. This PY-NLS partially overlaps the second zinc finger (ZnF2) of dTIS11. Importantly, mutations disrupting the capacity of the ZnF2 to coordinate a Zn2+ ion unmask dTIS11 and TTP PY-NLS and promote nuclear import. Taken together, our results indicate that the nuclear export of Drosophila and mammalian TIS11 proteins is mediated by CRM1 through diverging NESs, while their nuclear import mechanism might rely on a conserved PY-NLS whose activity is negatively regulated by ZnF2 folding.

In the second part, we present preliminary results which implicate the nucleo-cytoplasmic transport machinery in the assembly of stress granules (SGs) in mammalian cells. SGs contain silenced mRNPs which resemble stalled initiation complexes, and they form transiently in response to acute stress, concomitantly with a global arrest of translation. While their exact role remains undefined, it seems clear that SGs are able to exchange mRNPs with polysomes and with PBs, and that they are connected to post-transcriptional and translational regulations of gene expression during stress. Here, we show that inhibition of Transportin-1 expression or function does not affect the translational status of cells but impairs the assembly of stress granules. Finally, we show that Transportin-1 and -2B, but not -2A, localize into stress granules in response to several stresses.

In conclusion, we suggest two potential new roles for Transportins, in the nucleo-cytoplasmic traffic of TIS11 proteins on the one hand and in the assembly of stress granules on the other hand.

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Le compartimentage nucléo-cytoplasmique permet aux cellules eucaryotes de réguler l’expression génétique par des mécanismes post-transcriptionnels élaborés. Les ARN messagers subissent plusieurs étapes de maturation dans le noyau avant d’être exportés vers le cytoplasme où ils sont traduits et dégradés. Ces processus sont effectués via des protéines de liaison à l’ARN, ou RBPs. Beaucoup de RBPs exercent des fonctions différentes dans le noyau et dans le cytoplasme, et leur activité peut dès lors être rapidement modulée par une modification de leur localisation.

Le transport nucléo-cytoplasmique actif des protéines s’effectue à travers les pores nucléaires et fait majoritairement appel à des transporteurs solubles de la famille des karyophérines. Ceux-ci reconnaissent au sein des protéines à transporter une séquence-passeport appelée NLS (nuclear localization signal) ou NES (nuclear export signal) selon la direction nécessitée.

Le présent travail comporte deux parties. La première porte sur la localisation subcellulaire et le transport nucléo-cytoplasmique des protéines de la famille TIS11, et plus particulièrement de dTIS11 qui est le seul représentant de cette famille chez la Drosophile. Comme ses homologues dans d’autres espèces, dTIS11 est une RBP qui favorise la déadénylation et la dégradation de ses ARN messagers cibles. Nos résultats démontrent que dTIS11 fait la navette entre le noyau et le cytoplasme. L’export de dTIS11 hors du noyau est réalisé par la karyophérine CRM1 et fait appel à un NES différent de celui présent chez les protéines TIS11 mammaliennes. Nous identifions également un NLS cryptique au sein du domaine à deux doigts de zinc avec lequel dTIS11 lie l’ARN. Ce NLS correspond partiellement au signal consensus reconnu par la Transportine. Il est démasqué par la mutation du second doigt de zinc ;dans ces conditions, il permet l’import de dTIS11 par la Transportine. Enfin, nous montrons qu’il est conservé dans d’autres protéines de la famille TIS11.

Dans la seconde partie, nous nous intéressons aux granules de stress, qui sont des microdomaines cytoplasmiques dans lesquels se concentrent des RBPs et des ARN messagers non traduits en réponse à un stress cellulaire. Nous montrons que les karyophérines appartenant à la sous-famille des Transportines sont présentes dans ces granules et que l’inhibition de l’expression ou de la fonction des Transportines réduit la formation de ces granules en réponse à divers stress cellulaires. Nous écartons la possibilité que ce résultat soit un effet indirect d’un ralentissement du métabolisme traductionnel. Nos résultats suggèrent donc une implication des Transportines dans la formation des granules de stress.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Martin, Sophie. "Le composant des granules de stress G3BP : caractérisation phénotypique de souris KO, et identification de son interactome ribonucléoprotéique dans le cerveau de souris." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20247.

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Les protéines capables de lier des ARNs sont essentielles pour les différentes étapes de maturation de l'ARN messager (ARNm), en dirigeant leur localisation et leur devenir dans la cellule, et en formant avec les ARNs des particules ribonucléoprotéiques (mRNPs). Les mRNPS peuvent former des structures cellulaires dynamiques qui sont adressées vers des fonctions spécifiques. Ces granules, tels que les granules de stress formés suite à un stress cellulaire, contiennent des ARNm dont la traduction est inhibée et qui sont stockés transitoirement. Ma thèse a consisté en la caractérisation fonctionnelle de G3BP (RasGAP SH3 binding protein), une RBP exprimée de façon ubiquitaire chez l'homme et la souris, et impliquée dans l'assemblage des granules de stress. Par recombinaison homologue classique, des souris knock-out pour G3BP ont été générées. Ces souris ont une espérance de vie faible et des défauts du comportement associés au Système Nerveux Central, en particulier un phénotype de type ataxie. Des expériences d'électrophysiologie ont aussi montré une altération de la plasticité synaptique dans l'hippocampe des souris KO. J'ai donc réalisé des expériences d'immunoprécipitation après cross-link (Cross-Linking and Immunoprecipitation, CLIP) pour purifier à partir de cerveau de souris un complexe stable contenant G3BP, et les ARNs associés ont été identifiés par séquençage haut débit (High-Throughput Sequencing, HITS-CLIP). De façon surprenante, la plupart des cibles de G3BP correspondent à des transcrits codants mais qui contiennent des séquences introniques, et des ARNs non codants. De plus, mes résultats ont montré que l'absence de G3BP1 affecte la stabilité de ces transcrits pré-matures spécifiquement dans le cervelet, ce qui peut être corrélé au phénotype d'ataxie des souris KO G3BP1. Cela suggère un nouveau mécanisme de régulation qui passe par la stabilisation de transcrits pré-matures, qui pourraient être convertis en transcrits matures par exemple lors d'un stress et de la séquestration de G3BP dans les granules
RNA binding proteins (RBPs) are essential in the different steps of processing of the messenger RNAs (mRNAs), directing their localization and fate within the cell, and forming with them the ribonucleoprotein particles (mRNPs). mRNPs can assemble into dynamic cellular structures in which they are routed towards specific functions. RNA granules such as stress granules (SGs) contain translationally silenced mRNPs storing transiently repressed mRNAs.My thesis work consisted in the functional characterization of G3BP (RasGAP SH3 binding protein), an RBP that is expressed ubiquitously in both humans and mice and is involved in the assembly of SGs. Using classical homozygous recombination, viable G3BP1 knock out mice were generated that demonstrated short lifespan.and behavioral defects linked to the Central Nervous System (CNS), notably an ataxia phenotype. Electrophysiology experiments showed an alteration of synaptic plasticity in the hippocampus of KO mice. Therefore, I used Cross-Linking and Immunoprecipitation (CLIP) to purify from mouse brain a stable complex containing G3BP, and performed High-Throughput Sequencing (HITS-CLIP) to identify associated RNAs. Strikingly, most of the G3BP targets correspond to intron sequence-retaining transcripts and non-coding RNAs. My results also showed that G3BP1 depletion influences the stability of these premature transcripts in the cerebellum, which can be correlated to the ataxia phenotype of the G3BP1 KO mice. This comprehensive analysis suggests a new mechanism of gene regulation based on stabilization of silenced premature transcripts which might be converted to mature transcripts under stress condition and sequestration of G3BP in SGs

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Findley, Seth David. "Maelstrom and Drosophila nuage /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/9255.

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Ferrier, Emilie. "Rôle et mode d'action de l'UTP : RNA Uridylyltransférase URT1 dans l'uridylation et la dégradation des ARNm chez Aradopsis thaliana." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAJ053/document.

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La dégradation des ARN est un mécanisme essentiel à la régulation de l’expression des génomes. L’importance de l’uridylation dans les mécanismes de dégradation des ARN commence juste à être appréciée. Cette thèse présente l’étudede l’UTP :RNA Uridylyltransferase 1 (URT1) et de son rôle dans la dégradation des ARN chez Arabidopsis thaliana. L’étude des propriétés catalytiques de URT1 montre que cette uridylyltransférase est intrinsèquement spécifique des UTP et distributive pour les premières uridines ajoutées. URT1 est responsable in vivo de l’uridylation des ARNm après une étape de déadénylation, protégeant leur extrémité 3’ et polarisant la dégradation de 5’ en 3’. URT1 est localisée dans le cytosol au niveau des granules de stress et des processing bodies. Le mécanisme d’adressage de URT1 dans les processing bodies implique une partie de la région N terminale prédite comme intrinsèquement désorganisée, alors que le domainenucléotidyltransférase C terminal semble suffisant pour permettre l’adressage de URT1 au niveau des processing bodies et granules de stress en réponse à un stress thermique. Ces travaux de thèse ont permis de mieux comprendre les mécanismes et les rôles de l’uridylation dans la dégradation des ARNm chez Arabidopsis. Ils ouvrent des perspectives dans l’étude d’autres fonctions de l’uridylation comme l’inhibition de la traduction
RNA degradation is an essential mechanism for the regulation of genome expression. The importance of uridylation for RNA degradation is just emerging. This thesis presents the study of URT1 (UTP :RNA Uridylyltransferase 1) and its role in RNA degradation in Arabidopsis thaliana. URT1 is an uridylyltransferase intrinsically and strictly specific for UTP and is distributive for the first nucleotides added. URT1 uridylates mRNA in vivo after a deadenylation step. This uridylation protects mRNA’s3’ end from further attacks and polarise degradation in the 5’ to 3’ direction. This protection of 3’ ends by uridylation and its conferred polarity of 5’ to 3’ degradation are also detected in polysomes. Uridylation is therefore likely important in case of cotranslational degradation of mRNAs. A region in URT1’s N terminal region predicted to be intrinsically disorganised is required for addressing URT1 to processing bodies. However, following heat shock, the nucleotidyltransferase domain present in the C terminal region of URT1 is sufficient to address URT1 to both processing bodies and stress granules, This work contributes to a better understanding of the mechanisms and roles of uridylation in RNA degradation in Arabidopsis thaliana. These results also open perspectives for studying other functions of uridylation such as translation inhibition

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Emara, Mohamed Maged. "Analysis of the Cellular Proteins, TIA-1 and TIAR, and their Interaction with the West Nile Virus (WNV) 3' SL Minus-Strand RNA." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/biology_diss/38.

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The 3' terminal stem loop of the WNV minus-strand [WNV3'(-) SL] RNA was previously shown to bind the cell protein, T-cell intracellular antigen-1 (TIA-1), and the related protein, TIAR. These two proteins are known to bind AU-rich sequences in the 3' UTRs of some cellular mRNAs. AU stretches are located in three single-stranded loops (L1, L2, and L3) of the WNV3'(-) SL RNA. The RNA binding activity of both proteins was reduced when L1 or L2, but not L3, AU sequences were deleted or substituted with Cs. Deletion or substitution with Cs of the entire AU-rich sequence in either L1 or L2 in a WNV infectious clone was lethal for the virus while mutation of some of these nt decreased the efficiency of virus replication. Mutant viral RNAs with small plaque or lethal phenotypes had similar translational efficiencies to wildtype RNA, but showed decreased levels of plus-strand RNA synthesis. These results correlated well with the efficiency of TIA-1 and/or TIAR binding in in vitro assays. In normal cells, TIA-1 and TIAR are evenly distributed in the cytoplasm and nucleus. Between 6 and 24 hr after WNV infection, TIAR concentrated in the perinuclear region and TIA-1 localization to this region began by 24 hr. Similar observations were made in DV2 infected cells but at later times after infection. In infected cells, both proteins colocalized with dsRNA, a marker for viral replication complexes, and with viral non-structural proteins. Anti-TIAR or anti-TIA-1 antibody coimmunoprecipitated viral NS3 and possibly other viral nonstructural proteins. In response to different types stress, TIA-1 and TIAR recruit cell mRNA poly(A)+ into cytoplasmic stress granules (SG) leading to general translational arrest in these cells. SG were not induced by flavivirus infection and cells became increasingly resistant to arsenite induction of SG with time after infection. Processing Body (PB) assembly was also decreased beginning at 24 hr. These data suggest that the sequestration of first TIAR and then TIA-1 via their interaction with viral components in flavivirus infected cells inhibits SG formation and prevents the shutoff of host translation.

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Emara, Mohamed Maged. "Analysis of the Cellular Proteins, TIA-1 and TIAR, and their Interaction with the West Nile Virus (WNV) 3' SL Minus-Strand RNA." Digital Archive @ GSU, 2007. http://digitalarchive.gsu.edu/biology_diss/70.

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The 3' terminal stem loop of the WNV minus-strand [WNV3'(-) SL] RNA was previously shown to bind the cell protein, T-cell intracellular antigen-1 (TIA-1), and the related protein, TIAR. These two proteins are known to bind AU-rich sequences in the 3' UTRs of some cellular mRNAs. AU stretches are located in three single-stranded loops (L1, L2, and L3) of the WNV3'(-) SL RNA. The RNA binding activity of both proteins was reduced when L1 or L2, but not L3, AU sequences were deleted or substituted with Cs. Deletion or substitution with Cs of the entire AU-rich sequence in either L1 or L2 in a WNV infectious clone was lethal for the virus while mutation of some of these nt decreased the efficiency of virus replication. Mutant viral RNAs with small plaque or lethal phenotypes had similar translational efficiencies to wildtype RNA, but showed decreased levels of plus-strand RNA synthesis. These results correlated well with the efficiency of TIA-1 and/or TIAR binding in in vitro assays. In normal cells, TIA-1 and TIAR are evenly distributed in the cytoplasm and nucleus. Between 6 and 24 hr after WNV infection, TIAR concentrated in the perinuclear region and TIA-1 localization to this region began by 24 hr. Similar observations were made in DV2 infected cells but at later times after infection. In infected cells, both proteins colocalized with dsRNA, a marker for viral replication complexes, and with viral non-structural proteins. Anti-TIAR or anti-TIA-1 antibody coimmunoprecipitated viral NS3 and possibly other viral nonstructural proteins. In response to different types stress, TIA-1 and TIAR recruit cell mRNA poly(A)+ into cytoplasmic stress granules (SG) leading to general translational arrest in these cells. SG were not induced by flavivirus infection and cells became increasingly resistant to arsenite induction of SG with time after infection. Processing Body (PB) assembly was also decreased beginning at 24 hr. These data suggest that the sequestration of first TIAR and then TIA-1 via their interaction with viral components in flavivirus infected cells inhibits SG formation and prevents the shutoff of host translation.

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Soto-Rifo, Ricardo. "Translational control of HIV-1 and HIV-2 genomic RNA." Lyon, Ecole normale supérieure, 2010. http://www.theses.fr/2010ENSL0584.

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Les virus de la immunodéficience humaine de type 1 et 2 (VIH-1 et VIH-2) sont des pathogènes qui ont un grand impact sur la santé car plus de 33 millions de personnes sont infectées dans le monde. Les mécanismes qui contrôlent les étapes post-transcriptionelles de l’ARN génomique pendant les étapes tardives du cycle réplicatif ne sont pas très connu et donc les processus moléculaires qui permettent à l’ARN génomique de s’associer aux machineries cellulaires de traduction, transport ou dégradation restent à être déterminés. Dans ces travaux, nous avons contribué à améliorer notre connaissance sur les mécanismes qui contrôlent la synthèse des protéines à partir de l’ARN génomique de VIH-1 et VIH-2. Les résultats présentés dans ces travaux montrent que la structure d’ARN TAR joue un rôle primordial dans le contrôle des interactions de l’ARN génomique et la machinerie traductionnelle de la cellule. Nous montrons des données qui suggèrent une nouvelle étape lors du cycle réplicatif du VIH-2 dans laquelle l’ARN génomique est accumulé dans des granules cytoplasmiques avec des marqueurs des granules de stress. Nous mettons en évidence un mécanisme qui permettrait à l’ARN génomique du VIH-1 d’être exporté au cytoplasme et traduit de manière efficace grâce à l’helicase à ARN DDX3
Infections by Human immunodeficiency viruses type-1 and type-2 (HIV-1 and HIV-2) have an enormous impact in Human health as more than 33 million people is living with HIV/AIDS worldwide. The mechanisms controlling post-transcriptional events during the HIV life cycle have just started to capture the attention of scientists and most of the molecular processes allowing the genomic RNA to interact with the host machineries for translation, transport or decay are still obscure or in way to be determined. In this work, we contribute to the progress in the knowledge of the mechanisms controlling protein synthesis from the HIV-1 and HIV-2 genomic RNA. Results presented here provide evidence for the TAR RNA structure as a key player in controlling the interactions between the HIV-1 and HIV-2 genomic RNA with the host translational machinery. We also provide data for a new step during the HIV-2 life cycle that involves the accumulation of the genomic RNA in cytoplasmic granules containing several stress granules components. Finally, we present evidence for a potential mechanism by which nuclear export and protein synthesis are linked during the HIV-1 replication cycle. As such, we show that DEAD-box RNA helicase DDX3, previously implicated in Rev-mediated nuclear export, is absolutely required for HIV-1 genomic RNA translation. We determined the TAR structure as the viral determinant required for DDX3 function in translation. Strikingly, we also showed that DDX3 is specifically required for HIV-2 and SIV translation but not for FIV, HTLV-1, MLV or Line-1 suggesting that this function was acquired during primate lentiviruses evolution. Taken together, results obtained during this work highlight several key aspects of the HIV-1 and HIV-2 genomic RNA post-transcriptional control that may be critical for viral replication

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Bolinger, Cheryl Giles. "Study of translation control by a RNA helicase A-responsive post-transcriptional control element in Retroviridae." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1226513076.

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Budkina, Karina. "The role of an mRNA-binding protein YB-1 in formation of stress granules and translation." Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPASL006.

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Au cours de la vie de l'ARNm dans la cellule, l'ARNm existe en complexe avec des protéines et n'est jamais libre. Dans le cytoplasme, l'ARNm actif est associé aux ribosomes pour former les polyribosomes tandis que les ARNm réprimés s’associent avec certaines protéines de liaison à l'ARN (RBP) pour former des mRNP. Les mRNP réprimés sont généralement isolés dans le cytoplasme mais ils peuvent également être trouvés dans des compartiments appelés granules d’ARN, notamment lors d'un stress cellulaire. Ces granules d’ARN sont des organelles non membranaires contenant principalement de l'ARNm inactif et coexistent avec des polysomes. Selon les conditions environnementales, il y a un changement dans le ratio des ARNms trouvés dans les granules d’ARN ou dans les polysomes. De plus, il existe des différences dans la teneur en ARNm des différents types de ces organelles en fonction de leur localisation et de leurs fonctions. Actuellement, les granules de stress présentent un grand intérêt pour les chercheurs en raison de leur relation avec certaines maladies neurologiques. Les mutations trouvées dans certaines protéines de liaison à l'ARN telles que TDP43 et FUS sont directement liées à certaines maladies neurodégénératives telles que la sclérose latérale amyotrophique (SLA), la démence frontotemporale (FTLD) et la maladie d'Alzheimer (MA). Dans les neurones affectés, TDP-43 et FUS forment des agrégats cytoplasmiques alors que ces protéines se trouvent généralement dans le noyau dans des conditions physiologiques. Comme elles ont également été trouvées dans les granules de stress cytoplasmiques, les granules de stress peuvent servir d'intermédiaires pour la formation d'agrégats de FUS et TDP-43. En outre, FUS et TDP-43 contiennent des régions intrinsèquement désordonnées (IDR) qui contribuent à leur agrégation.La formation de granules de stress est stimulée par l'exposition à différents facteurs internes et / ou externes. Les granules de stress servent de lieu de stabilisation des ARNm et à les maintenir inactifs jusqu'à ce que les facteurs de stress disparaissent. On considère que les structures secondaires de l'ARNm jouent un rôle important dans l'assemblage des granules de stress. De telles structures servent aussi de sites de liaison pour les RBP, qui les stabilisent davantage (par exemple G3BP). La protéine de liaison Y-box 1 (YB-1) a également été identifiée comme un marqueur pour les granules de stress. YB-1 est une protéine de liaison à l'ARN qui accompagne l'ARNm dès sa synthèse dans le noyau jusqu’à sa dégradation dans le cytoplasme. YB-1 contient un domaine de choc froid (CSD) avec deux motifs de reconnaissance d'ARN (RNP-1 et RNP-2), ainsi qu'un domaine CTD non structuré similaire aux IDR. Pour la plupart des protéines impliquées dans la formation des granules de stress, leur activité stimulante de l'IDR dans ce processus a été démontrée. Dans le même temps, il existe quelques controverses concernant le rôle de YB-1 dans l'assemblage des granules de stress. Selon certains modèles, il y a lieu de le considérer comme un régulateur négatif dans la formation des granules de stress. Selon d'autres, YB-1 présente les propriétés d'un agent favorisant de l'assemblage de granules de stress. Par ailleurs, peu de travaux ont n'a été faits pour déchiffrer l'action de la protéine sur la traduction sous stress oxydatif. Ici, notre objectif était de démêler les mécanismes structuraux par lesquels YB-1 peut réguler négativement la formation de granules de stress et de clarifier son influence sur la traduction dans des conditions de stress
During mRNA life in cell mRNA exists in complex with proteins and is never free. In the cytoplasm, active mRNA is associated with ribosomes to form polyribosomes while repressed mRNAs in association with RNA-binding proteins forms mRNPs. Repressed mRNPs are generally isolated in the cytoplasm but they can also be found in compartments called mRNP granules, notably during cellular stress. Such mRNP granules are non-membrane organelles contains mostly translationally inactive mRNA and coexist with polysomes. Depending on the environmental conditions, there is a change in the ratio of mRNA found in these types of granules or in polysomes. In addition, there are differences in the mRNA content of the different types of such organelles depending on their localization and functions. Currently, stress granules are of great interest to researchers due to their relation to some neurological diseases. Mutations of some RNA-binding proteins such asTDP43 and FUS are directly linked to some neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTLD), and Alzheimer's disease (AD). In the affected neurons, TDP-43 and FUS form cytoplasmic aggregates while these proteins are generally found in the nucleus under physiological conditions. As they were also found in cytoplasmic stress granules, stress granules may serve as intermediates for the formation of FUS and TDP-43 aggregates. In addition, FUS and TDP-43 contain intrinsically disordered regions (IDRs) which contribute to their aggregation. The formation of stress granules is stimulated by exposure to different internal and/or external factors. Stress granules serve as a place for mRNA stabilization and keeping it inactive until stress factors disappear. It is considered that secondary structures of mRNA play a significant role in the assembly of stress granules. Such structures serve as binding sites for RBPs, which further stabilize them (e.g. G3BP). The Y-box binding protein 1 (YB-1) was also identified as a marker for stress granules. YB-1 is an RNA-binding protein that accompanies mRNA from its synthesis in the nucleus to degradation in the cytoplasm. YB-1 contains a cold shock domain (CSD) with two RNA-recognition motifs (RNP-1 and RNP-2), as well as an unstructured CTD domain similar to IDRs. For most of the proteins involved in the formation of stress granules, their stimulating activity of IDR in this process has been shown. At the same time, there are some controversies regarding the role of YB-1 in the assembly of granules. According to some sources, there is reason to consider it as a negative regulator. According to others, YB-1 exhibits the properties of an inducer during the assembly of stress granules. At the same time, no attempts were made to decipher the mechanism of action of the protein under oxidative stress.Here our aim was to unravel the structural mechanisms by which YB-1 can negatively regulate the formation of stress granules and to clarify its influence on translation in stress conditions

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Villalobos, Terrazas Daniela. "Análisis actual y proyecciones de la temperatura y precipitación del Norte Grande y su Altiplano en Chile: variabilidad (1970-2013) y cambio climático en el escenario futuro RCP 8.5 (2080)." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/144463.

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Memoria para optar al título de Geógrafo
El cambio y variabilidad climática son fenómenos que afectan a todo el planeta, provocando entre otros efectos, cambios importantes en las condiciones normales del clima, por ejemplo, acentuando condiciones extremas de sequía e inundaciones. Dentro de las zonas más amenazadas a estos cambios, el norte grande y su altiplano chileno podrían manifestar una alta probabilidad de sufrir severas transformaciones, con alzas importantes en su temperatura y aumento de la variabilidad de episodios pluviométricos. Utilizando la proyección de las superficies climáticas generadas por Pliscoff et al. (2014), y la proyección del Modelo de Circulación Atmosférica Global (GCM) del CSIRO ACCESS 1.3 para el escenario RCP 8.5, fue posible visualizar los cambios proyectados para el 2080, y sus efectos en los ecosistemas presentes, verificando patrones de disminución de gran parte de la precipitación y aumento de su variabilidad, y por otra parte, alza de la temperatura para el norte grande, en especial en el altiplano.

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Wu, Yuhong. "Structural studies of Human Caprin Protein." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/dissertations/1652.

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Human Caprin-1 and Caprin-2 are prototypic members of the caprin (cytoplasmic activation/proliferation-associated protein) protein family. Vertebrate caprin proteins contain two highly conserved homologous regions (HR1 and HR2) and C-terminal RGG motifs. Drosophila caprin (dCaprin) shares HR1 and RGG motifs but lacks HR2. Caprin-1 and Caprin-2 have important and non-redundant functions. The detailed molecular mechanisms of their actions remain largely unknown.

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Goulet, Isabelle. "New Roles for Arginine Methylation in RNA Metabolism and Cancer." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20293.

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Because it can expand the range of a protein’s interactions or modulate its activity, post-translational methylation of arginine residues in proteins must be duly coordinated and ‘decoded’ to ensure appropriate cellular interpretation of this biological cue. This can be achieved through modulation of the enzymatic activity/specificity of the protein arginine methyltransferases (PRMTs) and proper recognition of the methylation ‘mark’ by a subset of proteins containing ‘methyl-sensing’ protein modules known as ‘Tudor’ domains. In order to gain a better understanding of these regulatory mechanisms, we undertook a detailed biochemical characterization of the predominant member of the PRMT family, PRMT1, and of the novel Tudor domain-containing protein 3 (TDRD3). First, we found that PRMT1 function can be modulated by 1) the expression of up to seven PRMT1 isoforms (v1-7), each with a unique N-terminal region that confers distinct substrate specificity, and by 2) differential subcellular localization, as revealed by the presence of a nuclear export sequence unique to PRMT1v2. Second, our findings suggest that TDRD3 is recruited to cytoplasmic stress granules (SGs) in response to environmental stress potentially by engaging in methyl-dependent protein-protein interactions with proteins involved in the control of gene expression. We also found that arginine methylation may serve as a general regulator of overall SG dynamics. Finally, we uncovered that alteration of PRMT1, TDRD3, and global arginine methylation levels in breast cancer cells may be closely associated with disease progression and poor prognosis. Therefore, further studies into the pathophysiological consequences ensuing from misregulation of arginine methylation will likely lead to the development of novel strategies for the prevention and treatment of breast cancer.

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Orsborn, April Marie. "Analysis of interactions between the germline RNA helicases (GLHs) and their regulators KGB-1 and CSN-5 in Caenorhabditis elegans." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4499.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. Includes bibliographical references.

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Maillot, Maxence. "Caractéristaion des effets spatiaux dans les grands coeurs RNR : méthodes, outils et études." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4046/document.

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Les réacteurs nucléaires à neutrons rapides sont une solution à long terme pour la production d’énergie car ils valorisent le Plutonium et peuvent utiliser tout le stock de d’Uranium appauvri. Les contraintes actuelles en termes de sûreté requièrent néanmoins des innovations pour favoriser un comportement naturel du cœur lors de transitoires incidentels en augmentant le temps de grâce et la marge à la fusion. Les innovations apportées aux cœurs (hauteur réduite, cœur hétérogène, puissance volumique limitée) induisent un accroissement de la taille des réacteurs. Cette évolution a des conséquences de sûreté essentiellement positives comme la réduction de l’effet de vidange mais d’autres comme la déformation de la nappe de puissance méritent attention. Cette thèse a permis de mieux appréhender ces spécificités au travers du calcul et de l’analyse des harmoniques du flux puis des matrices de fission. Ces études, en soutien au cœur d’ASTRID, ont permis de conforter les options de conception
The need for energy is a matter of growing concern in the world today, in relation to global climate change. Nuclear energy is of interest because it does not produce greenhouse gases, and it is able to generate a substantial amount of energy at a given time. However, it needs fissile material to operate. Fuel economy is then a sine qua none condition for the development of this energy. Sodium Fast Reactors are a solution for the future of nuclear energy. These reactors are indeed able to use much less Uranium for the same amount of energy released. However, the safety constraints in accordance with todays standards (“forgiving behavior”) require new core designs, which are highly heterogeneous axially and rather flat. Finally, this evolution in reactor design (reduced power density and limited axial height) implies a significant increase in the reactor diameter. It has consequences from both an economic (Pu inventory, vessel size) and operational (power shape stabilization during irradiation) point of view. The understanding of this phenomena is the topic of this PhD

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De, Leeuw Frédéric. "Etude de la protéine CIRP et sa fonction dans le métabolisme des ARN messagers." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210577.

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La protéine CIRP (Cold Induced RNA binding Protein) est une petite protéine de liaison à l’ARN de 172 acides aminés, qui est constituée du côté amino-terminal d’un domaine de liaison à l’ARN de type RRM (RNA recognition motif), et d’une partie carboxy-terminale riche en glycine et arginine qui comprend plusieurs motifs RGG. Elle a été identifiée comme étant inductible par hypothermie mais aussi par irradiation aux UV et par hypoxie. Nous avons analysé son expression et sa localisation en réponse à différents stress cellulaires. Nous avons montré qu’un traitement à l’arsénite qui induit un stress oxydant n’altère pas l’expression de CIRP provoque sa localisation dans les granules de stress (SG). Les SG sont des structures ribonucléoprotéiques cytoplasmiques contenant des complexes de pré-initiation incompétents pour la traduction, et qui s’accumulent dans les cellules exposées à un stress. Ces structures constituent des sites de triages des ARNm, dans lesquels les ARNm sont soit stockés en attente d’une réinitiation de la traduction une fois le stress surmonté, soit destinés à être dégradés. La protéine CIRP se localise dans les SG que ce soit suite à un stress cytoplasmique ou du réticulum endoplasmique. Nous avons montré également que la localisation de la protéine CIRP dans les SG se déroule indépendamment de la présence de la protéine TIA-1 qui a été décrite comme responsable de l’assemblage des SG. De plus la surexpression de la protéine CIRP conduit à la formation de SG. Nous suggérons donc qu’il existe plusieurs voies qui mènent à l’assemblage de ces structures. En outre, nous avons analysé la localisation de mutants par délétion de la protéine CIRP et avons montré que le domaine RRM et le domaine RGG peuvent indépendamment localiser la protéine dans les SG. Par contre, la méthylation des résidus arginine du domaine RGG est une modification nécessaire à la localisation de CIRP dans les SG. Ensuite, nous avons étudié la fonction de la protéine CIRP dans le métabolisme des ARN messagers. Nous avons montré par une méthode d’adressage, que CIRP est un répresseur de la traduction des ARNm et que le domaine carboxy-terminal est nécessaire et suffisant à cette fonction.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Brito, Anderson Dantas da Silva. "Em nome(s) dos interesses: imagin?rios topon?micos do Rio Grande do Norte na Primeira Rep?blica." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/16961.

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Made available in DSpace on 2014-12-17T15:25:17Z (GMT). No. of bitstreams: 1 AndersonDSB_DISSERT.pdf: 4868485 bytes, checksum: 66fb82a21534bbaa6e3f0e444688eef7 (MD5) Previous issue date: 2012-08-31
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
This paper has the imaginary names as a theme, from which we aim to analyze the imaginaries and invested interests that characterized the implementation and the legitimation of the First Republic in Rio Grande do Norte (1889 1930), making the process of registering names history in that place. For the construction of our object, we studied laws and provincial, state and municipal decrees; annual messages of governors; articles of the following newspapers O Povo, A Rep?blica, Di?rio do Natal, O Seridoense, A Not?cia and Jornal das Mo?as; the local cartography and historiography that talk about the study of names. The use of these resources, allied to the empiric method, was driven by a theoretic methodological contribution based on the history of the political imaginary, as discussed by Cornelius Castoriadis, Ren? R?mond, Michel de Certeau and Maria Dick. For the understanding of the imaginaries that (de)limited the spaces of Rio Grande do Norte concerning its names during the First Republic, we bring moment back to the two last imperial decades moment of cleavage between Empire and Republic essential for the fomentation of the imaginary that embodied the organization of our study. From this period, we observe, through the names of some cities, how the northern space would be aligned to the imaginary dynamic of the new political system of the nation, and it had followed to a redirection process of the giving names action, according to the interests of the family organization Albuquerque Maranh?o, revealed while determining the names of cities, towns, streets, schools, buildings, etc., in thankfulness to the memory of its members. In the sequence we verified how a new dynamic of giving names helped to understand the process of political transition from the Coast to the Sert?o, and at the same time affirmed the power of the political and economical seridoense elite towards the government of the state in the two last decades of the First Republic
Esse trabalho tem como tem?tica imagin?rios topon?micos, a partir da qual objetivamos analisar os imagin?rios e interesses investidos que caracterizaram a implanta??o e a legitima??o da Primeira Rep?blica (1889-1930) no Rio Grande do Norte, historicizando o processo de toponimiza??o de tal espa?o. Para a constru??o de nosso objeto perscrutamos leis e decretos provinciais, estaduais, e municipais; mensagens anuais de governadores; artigos dos jornais O Povo, A Rep?blica, Di?rio do Natal, O Serid?ense, A Not?cia, e Jornal das Mo?as; a cartografia, e a historiografia local que trata da topon?mia. A utiliza??o dessas fontes aliadas a empiria foram conduzidas por um aporte te?rico-metodol?gico baseado na hist?ria do imagin?rio pol?tico atrav?s de Cornelius Castoriadis, Ren? R?mond, Michel de Certeau e Maria Dick. Para a compreens?o dos imagin?rios que (de)marcaram toponimicamente os espa?os do Rio Grande do Norte durante a Primeira Rep?blica inicialmente retornaremos ?s duas ?ltimas d?cadas imperiais, enquanto momento de clivagem entre Imp?rio e Rep?blica, fundamental para a fomenta??o dos imagin?rios que corporificaram a organiza??o de nossa problem?tica. Este primeiro olhar trata de observar atrav?s dos nomes de algumas cidades como o espa?o norte-rio-grandense deveria est? alinhado com a din?mica imagin?ria do novo regime pol?tico da na??o, seguindo para um processo de redirecionamento das pr?ticas nomeativas em conformidade com a organiza??o familiar Albuquerque Maranh?o ao enunciar nos nomes de cidades, vilas, ruas, escolas, edif?cios, etc o reconhecimento ? mem?ria de seus membros, para na sequ?ncia verificar como uma nova din?mica nomeativa ajudou a entender o processo de transi??o pol?tica do Litoral para o Sert?o, e ao mesmo tempo afirmando o poder da elite pol?tica e econ?mica seridoense ? frente do governo do estado nas duas ?ltimas d?cadas da Primeira Rep?blica

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Silva, Milena de Souza da. "Cotidiano, escrita de si e coronelismocorrespond?ncia de Manoel de Freitas Valle Filho a Borges de Medeiros (1903-1916)." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2010. http://tede2.pucrs.br/tede2/handle/tede/2352.

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Este trabalho que traz por t?tulo Cotidiano, Escritas de si e o Coronelismo: a correspond?ncia de Manoel de Freitas Valle Filho a Borges de Medeiros (1903 a 1916), visa analisar um Corpus documental ainda n?o usado, formado por 58 correspond?ncias de Manoel de Freitas Valle Filho a Borges de Medeiros, no per?odo entre 1903 a 1916. Justifica-se por tratar de uma conjuntura da hist?ria do Rio Grande do Sul de extrema import?ncia, pois ? o momento de cria??o de uma forma de poder pol?tico o coronelismo de historiografia lacunosa; tamb?m por analisar correspond?ncias reservadas trocadas entre coron?is ga?chos; h? poucas informa??es na historiografia ga?cha sobre o coronel Manoel de Freitas Valle Filho, que foi Vice-Presidente do Estado do Rio Grande do Sul junto ao Presidente Carlos Barbosa Gon?alves, no per?odo que vai de 1908 a 1912. Essa fase foi um momento de descontinuidade no longo per?odo em que Borges de Medeiros exerceu um poder autorit?rio neste Estado (1898 1928). O trabalho tem como objetivo: Investigar as rela??es entre o chefe pol?tico estadual Borges de Medeiros e o chefe pol?tico local Manoel de Freitas Valle Filho, no per?odo de 1903 a 1916, protagonistas do coronelismo ga?cho. Tendo em vista as rela??es pessoais de Manoel de Freitas Valle Filho com o partido de oposi??o ao PRR, questiona-se at? que ponto a presen?a do mesmo, como Vice-Governador do Estado do Rio Grande do Sul, pode ter sido tramada para acalmar os ?nimos da oposi??o? Constata-se nas correspond?ncias, que Freitas Valle era um autor que escrevia discursos com objetivos de quem deseja apaziguar ?nimos, na busca de resolver disc?rdias, sem, entretanto, lograr agradar a todos, como evidenciam suas cartas.

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Kornd?rfer, Ana Paula. ""An international problem of serious proportions" : a coopera??o entre a Funda??o Rockefeller e o governo do estado do Rio Grande do Sul no combate ? ancilostom?ase e seus desdobramentos (1919-1929)." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2013. http://tede2.pucrs.br/tede2/handle/tede/2463.

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In "An international problem of serious proportions": The cooperation between the Rockefeller Foundation and the Government of the State of Rio Grande do Sul to fight ancylostomiasis and its consequences (1919-1929)", our proposal is to analyze the cooperation between the International Health Board of the Rockefeller Foundation and the government of the state of Rio Grande do Sul to fight a rural endemic disease, ancylostomiasis, in the 1920s, and the developments and consequences of this cooperation on public health in the state, both as regards the fight against ancylostomiasis and the organization of health in the state, taking aspects of the international, national and local context into account. Based on the discussion in the literature concerning the topic and the analysis of the documents produced, especially by the Rockefeller Foundation (reports, letters and publications), and by the government of the state of Rio Grande do Sul (Reports of the Department of the State for Internal and Foreign Affairs), we shall focus on activities to fight the disease performed in Rio Grande do Sul municipalities as a result of the cooperation between the Foundation and the state government, guided by the North American institution and performed through the state Directorate of Hygiene between 1920 and 1923.
Em An international problem of serious proportions : A coopera??o entre a Funda??o Rockefeller e o governo do estado do Rio Grande do Sul no combate ? ancilostom?ase e seus desdobramentos (1919-1929), nossa proposta ? analisar, levando em considera??o aspectos do contexto internacional, nacional e local, a coopera??o entre a divis?o internacional de sa?de International Health Board da Funda??o Rockefeller e o governo estadual do Rio Grande do Sul no combate a uma endemia rural, a ancilostom?ase, na d?cada de 1920, e os desdobramentos, as consequ?ncias desta coopera??o na sa?de p?blica estadual, tanto no que se refere ao combate ? ancilostom?ase em si quanto ? organiza??o da sa?de no estado. A partir da discuss?o de bibliografia pertinente ao tema e da an?lise de documenta??o produzida, principalmente, pela Funda??o Rockefeller (relat?rios, correspond?ncia e publica??es) e pelo governo do estado do Rio Grande do Sul (Relat?rios da Secretaria de Estado dos Neg?cios do Interior e Exterior), enfocaremos as atividades de combate ? doen?a realizadas em munic?pios ga?chos a partir da coopera??o entre a Funda??o e o governo estadual, orientadas pela institui??o norte-americana e realizadas atrav?s da Diretoria de Higiene estadual entre 1920 e 1923. Al?m disso, discutiremos tamb?m o trabalho de combate ? ancilostom?ase mantido pelo governo estadual ap?s o t?rmino da coopera??o com a Funda??o, com a organiza??o do Servi?o de Postos de Profilaxia Rural estadual em funcionamento entre 1924 e 1929. Por fim, abordaremos a atua??o da Funda??o na forma??o de profissionais de sa?de p?blica, pois, durante a coopera??o entre a institui??o e o governo estadual, um m?dico da Diretoria de Higiene, Fernando de Freitas e Castro, recebeu uma bolsa para realizar estudos em sa?de p?blica nos Estados Unidos entre 1922 e 1923. Em 1929, Freitas e Castro, ent?o ? frente da pasta da sa?de no Rio Grande do Sul, p?s fim ?s atividades do Servi?o de Postos de Profilaxia Rural a partir da proposta de uma Reforma Sanit?ria que introduzia, no estado, os health centers ou centros de sa?de, um modelo de organiza??o em sa?de p?blica difundido pela Funda??o.

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Fernandes, Saul Estevam. "O (in)imagin?vel elefante mal-ajambrado: a quest?o de limites entre o Cear? e o Rio Grande do Norte e o exame da forma??o espacial e identit?ria norte-rio-grandense na Primeira Rep?blica." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/16959.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
This study s main goal is to analyze the way the limits between Cear? and Rio Grande do Norte states, the so called Grossos matter, has been associated to the norte-rio-grandense spacial and identity formation during the first republic period. Thus, a consistet number of sources: RN and CE old newspapers, as well as a rep?blica from Natal and Fortaleza and o mossoroense ; historical drafts from the historical and geographical institute associated and historical, gographical and anthropological institute of Cear?; the A??o C?vel Origin?ria de n? 6 from the supreme federal tribunal and many other cartographies. The documents haven t been hierarchized, neither accepted as proof effects, but understood as the base matter for this text composition by the deconstruction of the analyzed discusses. In order to do that the abla??o or bricolagem method, without quotations marks or long quotations themselves, has been used. Along the three analyzed charpters: the two phases the litigious was found, since its beginning yet in the XVIII century until 1888 and its return within the republic proclamation, in the 1920 resolution; the development of the documental, historical and identity dispute between IHGA-CE and IHG-RN; and, at last, the political game existing between the Albuquerque Maranh?o oligarchy , Manuel Pereira Reis and Rui Barbosa, explaining the intentions, silent and miths built along the time by these intellectual participations
O objetivo deste trabalho ? analisar de que maneira a quest?o de limites entre o Cear? e o Rio Grande do Norte, a chamada de Quest?o de Grossos, esteve associada na forma??o espacial e identit?ria norte-rio-grandense na Primeira Rep?blica. Para tanto, utilizamos um elevado n?mero de fontes: jornais norte-rio-grandenses e cearenses da ?poca, como A Rep?blica de Natal e Fortaleza e O Mossoroense; escritos historiogr?ficos dos s?cios do Instituto Hist?rico e Geogr?fico do Rio Grande do Norte (IHG-RN) e do Instituto Hist?rico, Geogr?fico e Antropol?gico do Cear? (IHGA-CE) presentes em suas revistas; a A??o C?vel Origin?ria de n? 6 do Supremo Tribunal Federal (STF) e diversas cartografias. N?o hierarquizamos os documentos analisados, nem tampouco os compreendemos como efeitos de provas, mas como material de trabalho que constr?i o texto a partir da desconstru??o dos discursos analisados. Para tanto, fazemos uso do m?todo abla??o ou bricolagem, n?o utilizando aspas, nem tampouco cita??es longas. Ao longo dos tr?s cap?tulos analisamos: as duas fases que o lit?gio se encontrou, desde o seu come?o ainda no s?culo XVIII at? 1888 e sua retomada com a Proclama??o da Rep?blica, com sua resolu??o em 1920; o desenrolar da disputa no plano documental, historiogr?fico e identit?rio entre o IHGA-CE e o IHG-RN; e, por fim, o jogo pol?tico existente entre a oligarquia Albuquerque Maranh?o, Manuel Pereira Reis e Rui Barbosa, explicitando ainda as inten??es, sil?ncios e mitos constru?dos ao longo do tempo nas participa??es desses intelectuais

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Saccol, Tassiana Maria Parcianello. "Um propagandista da Rep?blica : pol?tica, letras e fam?lia na trajet?ria de Joaquim Francisco de Assis Brasil : d?cada de 1880." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2013. http://tede2.pucrs.br/tede2/handle/tede/2455.

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This paper analyzes the period of republican propaganda in Brazil (between 1880 and 1889) through the agency of a main character: Joaquim Francisco de Assis Brasil. The analysis of the trajectory of this young propagandist and his investments in the world of literacy and politics helps to reflect on two phenomena discussed throughout the text: the circulation of ideas in Brazil in the late nineteenth century and the strength of the republican movement in the countryside and missions in the state Rio Grande do Sul, Southern Brazil. Our focus is on the range of social relations in which Assis Brasil was involved. Therefore, he was always taken in interaction with other individuals such as their family, friends and political associates. The use of prosopography and the concepts of social networking, family and mediation strategy are some of the methodological theoretical contributions that allowed us to perform this research, based on the study of the social context in that period. Thus, it is possible to identify that young propagandists were not used to acting alone but they were part of a project shared by other family members which sought the access to power. Similarly, the existence of some bonds of friendship and kinship as well as the subsequent formulation of the relationship networks among propagandists from the most diverse Brazilian provinces collaborated to spread the republican ideal. On the other hand, by trying to identify the profile of the republicans from the third constituency, who also contributed to the election of Assis Brasil to the position of provincial deputy, we conclude that this group was formed from social rural roots - most of them involved with the raising of cattle, and with strongly hierarchical ideas while the analysis of the profile of the leaders from Rio-Grandense Republican Party demonstrated strong professional feature in this group, even though they belonged to families of rural society elites, who were traditionally involved in conservative politics of the province. At last, our focus is on the performance of Assis Brasil as provincial deputy and about his trial seeking grants and support to the industry of cattle production from the parliament so that it could benefit not only his family but also relatives, friends and his political base in the border region of southern Brazil.
O presente trabalho analisa o per?odo da propaganda republicana (entre os anos de 1880 e 1889) atrav?s da atua??o de um personagem principal: Joaquim Francisco de Assis Brasil. A an?lise da trajet?ria do jovem propagandista e de seus investimentos no mundo das letras e da pol?tica colabora para pensarmos a respeito de dois fen?menos trabalhados ao longo do texto: a circula??o de ideias no Brasil de fins do s?culo XIX e a for?a do movimento republicano nas regi?es da campanha e missioneira, no Rio Grande do Sul. Nosso enfoque recai sobre o leque de rela??es sociais nas quais Assis Brasil estava envolto. Logo, ele ? tomado sempre em intera??o com outros indiv?duos, sejam eles seus familiares, amigos e correligion?rios pol?ticos. A utiliza??o da prosopografia e o uso das no??es de rede social, estrat?gia familiar e mediador s?o alguns dos aportes te?ricos metodol?gicos que nos permitiram realizar esta investiga??o, partindo de uma leitura do social. Nesse sentido, ? poss?vel identificar que os jovens propagandistas n?o atuavam isoladamente, mas, pelo contr?rio, faziam parte de um projeto compartilhado pelos demais membros da fam?lia e que visava acessar o poder. Do mesmo modo, a exist?ncia de alguns la?os de amizade e parentesco e a consequente formula??o de redes de relacionamento entre os propagandistas das mais variadas prov?ncias brasileiras colaboravam na divulga??o do ideal republicano. Por outro lado, tentando identificar o perfil dos republicanos do terceiro c?rculo eleitoral, e que colaboraram para a elei??o de Assis Brasil ao cargo de deputado provincial, conclu?mos que se tratava de um grupo com bases sociais rurais, envolvido em sua maioria com a cria??o de gado, e fortemente hierarquizado, enquanto que a an?lise do perfil das lideran?as do Partido Republicano Rio-Grandense demonstrou o forte car?ter profissional deste grupo, muito embora os mesmos pertencessem ?s fam?lias de elites estancieiras, tradicionalmente envolvidas com a pol?tica conservadora da prov?ncia. Por fim, nosso foco recai sobre a atua??o de Assis Brasil como deputado provincial e sobre a tentativa deste em buscar subs?dios e apoio ? ind?stria pecuarista no parlamento, beneficiando, assim, n?o s? a sua fam?lia, como tamb?m parentes, amigos e sua base pol?tica na fronteira.

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Senna, Adriana Kivanski de. "As tentativas de implanta??o do div?rcio absoluto no Brasil e a imprensa Rio-Grandina : 1889 1916." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2006. http://tede2.pucrs.br/tede2/handle/tede/2395.

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Tese n?o cont?m resumo

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Magalh?es, Claiton dos Santos. "O trabalho do rep?rter no processo de integra??o do impresso para o online no Di?rio Ga?cho, um jornal popular." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2015. http://tede2.pucrs.br/tede2/handle/tede/6390.

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Analyzing a case of convergence of printed to the online in a popular newspaper, the present work aims to discuss the new functions and tasks that are assigned to the report. The theories of news, the basic work of the reporter, and mobile technologies digital and its impact on productive routines of writing, serve as the basis for the study. The research, performed in the newspaper Di?rio Ga?cho, in Porto Alegre, proposes a discussion about the influences of webjournalism at work the reporter and in its daily function to capture the events of a reality.
Analisando um caso de converg?ncia do impresso para o online em um jornal popular, o presente trabalho tem por objetivo discutir as novas fun??es e tarefas atribu?das ? reportagem. As teorias da not?cia, mat?ria b?sica do trabalho do rep?rter, e as tecnologias m?veis digitais e seu impacto nas rotinas produtivas da reda??o, servem como base para o estudo. A pesquisa, feita no jornal Di?rio Ga?cho, de Porto Alegre, prop?e uma discuss?o sobre as influ?ncias do webjornalismo no trabalho do rep?rter e na sua fun??o di?ria de captar os acontecimentos de uma realidade.

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Francisco, J?lio C?sar Bittencourt. "Dos cedros aos pampas : imigra??o s?rio-libanesa no Rio Grande do Sul, identidade e assimila??o (1890-1949)." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2017. http://tede2.pucrs.br/tede2/handle/tede/7771.

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This thesis refers to the history and the memory of Syrian-Lebanese immigration in Rio Grande do Sul, in the period from the last decade of the nineteenth century to the 1940s, more precisely between the years of 1890 and 1949, a temporal lapse that corresponds to two generations of immigrants, between their arrival in the country, adaptation to the new land and integration with the ?gaucho? culture. It aims to contribute to the knowledge of the origins of the Arab immigration in the state, the periods in which immigrants arrived, their places of fixation, the activities they carried out, the sociability?s they built, the institutions they founded, especially in Porto Alegre. The analysis is based on the use of diverse sources, such as books and periodicals; primary source documentation gathered in historical archives and museums; interviews; academic, memoirist and biographical literature; as well as websites and electronic documentation found on the internet. From a methodological point of view, the use of oral history as a privileged instrument for the production, analysis and interpretation of data and information made possible collected and highlight testimonies given by Arab descendants residing in Rio Grande do Sul. To situate the Levantine immigrant of the late nineteenth and early twentieth centuries, in a Middle East plunged in transnational issues, the work initially addresses the period of disintegration of the Ottoman Empire, the implementation of the French Mandate in Syria and Lebanon as well as the consequences of such fate in Porto Alegre. The independence of Lebanon and Syria in the 1940's closes the research chronological period. It was tried to demonstrate how these immigrants, coming from the Middle East, inserted and adapted in Rio Grande do Sul amid an environment dominated by other more numerous migratory waves, how they manage building their spaces of sociability?s and its path. The main result of the research was the certainty that the greatest asset of the Syrian and Lebanese descendants is the belonging to the gaucho culture, which they are inserted, without, however, loose their Lebanese or Arab identity, with all the meanings and representations that this implies.
Esta tese refere-se ? hist?ria e ? mem?ria da imigra??o s?rio-libanesa no Rio Grande do Sul, no per?odo que vai do ?ltimo dec?nio do s?culo XIX at? a d?cada de 1940, mais precisamente entre os anos de 1890 e 1949, lapso temporal que corresponde a duas gera??es de imigrantes, entre sua chegada ao pa?s, adapta??o ? nova terra e integra??o ? cultura ga?cha. Tem como objetivo contribuir para o conhecimento das origens da imigra??o ?rabe no estado, os per?odos em que aqui chegaram os imigrantes, seus locais de fixa??o, as atividades que exerceram, as sociabilidades que constru?ram, as institui??es que fundaram, especialmente em Porto Alegre. A an?lise est? baseada na utiliza??o de fontes diversas, tais como livros e artigos de peri?dicos; documenta??o prim?ria reunida em arquivos hist?ricos e museus; entrevistas; literatura acad?mica, memorialista e de cunho biogr?fico; al?m de sites e documenta??o eletr?nica encontrados na internet. Do ponto de vista metodol?gico, destaca-se a utiliza??o da hist?ria oral como instrumento privilegiado de produ??o, an?lise e interpreta??o de dados e informa??es coletados por meio de depoimentos concedidos ao autor por descendentes de imigrantes ?rabes residentes no Rio Grande do Sul. A fim de situar o imigrante s?rio-liban?s de fins do s?culo XIX e in?cio do XX, num Oriente M?dio mergulhado em quest?es transnacionais, o trabalho aborda inicialmente o per?odo de desintegra??o do Imp?rio Otomano, a implementa??o do Mandato Franc?s na S?ria e no L?bano no come?o da d?cada de 1920 e as suas consequ?ncias no Rio Grande do Sul, at? as independ?ncias desses pa?ses no fim da d?cada de 1940. Procurou-se demonstrar quem s?o e de que forma esses imigrantes oriundos do Oriente M?dio se organizaram e se inseriram no Rio Grande do Sul, onde se estabeleceram quando chegaram e de que forma constru?ram suas sociabilidades. Tudo isso em meio a um ambiente dominado por outras levas migrat?rias mais numerosas. O principal resultado da pesquisa foi a certeza de que o maior patrim?nio dos descendentes de imigrantes s?rios e libaneses ? o pertencimento ? cultura ga?cha, com a qual se identificaram, sem, no entanto, deixarem de se reconhecer como libaneses ou ?rabes, com todos os significados e representa??es que isso implica.

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Biavaschi, M?rcio Alex Cordeiro. "Rela??es de poder coronelistas na regi?o colonial italiana do Rio Grande do Sul durante o per?odo borgista (1903-1928)." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2011. http://tede2.pucrs.br/tede2/handle/tede/2368.

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Esta Tese de Doutorado objetiva analisar as condi??es da manuten??o do poder coronelista em munic?pios da regi?o colonial italiana (Ant?nio Prado, Bento Gon?alves, Caxias do Sul, Garibaldi, Guapor? e Veran?polis), sobretudo do modo como os colonos, os imigrantes e seus descendentes, se organizaram para se fazer ouvir politicamente, como grupos de press?o frente ?s imposi??es do poder municipal e estadual do Partido Republicano Rio-Grandense (PRR). Assim, os coron?is burocratas, intendentes quase permanentes daqueles munic?pios, n?o ligados ? estrutura de poder local, cumpriram importante papel na inser??o da pol?tica borgista na regi?o. Contudo, este projeto pol?tico estava invariavelmente pontuado pelos interesses econ?micos das popula??es coloniais, ao pre?o da perda de legitimidade do PRR, que se refletiria em preju?zos eleitorais, no surgimento de dissid?ncias internas e em constrangimentos perante as oposi??es. O coronelismo foi um sistema pol?tico que predominou em um momento hist?rico espec?fico no Brasil, a Rep?blica Velha (1889-1930). Por esta raz?o, necessita-se analis?-lo em uma perspectiva abrangente, ao levar em considera??o as especificidades do campo econ?mico, pol?tico e cultural de um dado espa?o social nas quais as problem?ticas em estudo se inserem, sendo imposs?vel teorizar de modo homog?neo um sistema pol?tico como o coronelismo que se apresentava de modo diverso conforme as particularidades regionais.

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48

Kaushansky, Laura J. "Investigating the Effects of Mutant FUS on Stress Response in Amyotrophic Lateral Sclerosis: A Thesis." eScholarship@UMMS, 2008. http://escholarship.umassmed.edu/gsbs_diss/792.

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Abstract:

During stress, eukaryotes regulate protein synthesis in part through formation of cytoplasmic, non-membrane-bound complexes called stress granules (SGs). SGs transiently store signaling proteins and stalled translational complexes in response to stress stimuli (e.g. oxidative insult, DNA damage, temperature shifts and ER dysfunction). The functional outcome of SGs is proper translational regulation and signaling, allowing cells to overcome stress. The fatal motor neuron disease Amyotrophic Lateral Sclerosis (ALS) develops in an age-related manner and is marked by progressive neuronal death, with cytoplasmic protein aggregation, excitotoxicity and increased oxidative stress as major hallmarks. Fused in Sarcoma/Translocated in Liposarcoma (FUS) is an RNA-binding protein mutated in ALS with roles in RNA and DNA processing. Most ALS-associated FUS mutations cause FUS to aberrantly localize in the cytoplasm due to a disruption in the nuclear localization sequence. Intriguingly, pathological inclusions in human FUSALS cases contain aggregated FUS as well as several SG-associated proteins. Further, cytoplasmic mutant FUS incorporates into SGs, which increases SG volume and number, delays SG assembly, accelerates SG disassembly, and alters SG dynamics. I posit that mutant FUS association with stress granules is a toxic gain-of-function in ALS that alters the function of SGs by interaction with SG components. Here, I show that mutant FUS incorporates in to SGs via its Cterminal RGG motifs, the methylation of which is not required for this localization. Further, I identify protein interactions specific to full-length mutant FUS under stress conditions that are potentially capable of interacting with FUS in SGs. Finally, I demonstrate a potential change in the protein composition of SGs upon incorporation of mutant FUS. These findings advance the field of ALS and SG biology, thereby providing groundwork for future investigation.

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49

Kaushansky, Laura J. "Investigating the Effects of Mutant FUS on Stress Response in Amyotrophic Lateral Sclerosis: A Thesis." eScholarship@UMMS, 2015. https://escholarship.umassmed.edu/gsbs_diss/792.

Full text

Abstract:

During stress, eukaryotes regulate protein synthesis in part through formation of cytoplasmic, non-membrane-bound complexes called stress granules (SGs). SGs transiently store signaling proteins and stalled translational complexes in response to stress stimuli (e.g. oxidative insult, DNA damage, temperature shifts and ER dysfunction). The functional outcome of SGs is proper translational regulation and signaling, allowing cells to overcome stress. The fatal motor neuron disease Amyotrophic Lateral Sclerosis (ALS) develops in an age-related manner and is marked by progressive neuronal death, with cytoplasmic protein aggregation, excitotoxicity and increased oxidative stress as major hallmarks. Fused in Sarcoma/Translocated in Liposarcoma (FUS) is an RNA-binding protein mutated in ALS with roles in RNA and DNA processing. Most ALS-associated FUS mutations cause FUS to aberrantly localize in the cytoplasm due to a disruption in the nuclear localization sequence. Intriguingly, pathological inclusions in human FUSALS cases contain aggregated FUS as well as several SG-associated proteins. Further, cytoplasmic mutant FUS incorporates into SGs, which increases SG volume and number, delays SG assembly, accelerates SG disassembly, and alters SG dynamics. I posit that mutant FUS association with stress granules is a toxic gain-of-function in ALS that alters the function of SGs by interaction with SG components. Here, I show that mutant FUS incorporates in to SGs via its Cterminal RGG motifs, the methylation of which is not required for this localization. Further, I identify protein interactions specific to full-length mutant FUS under stress conditions that are potentially capable of interacting with FUS in SGs. Finally, I demonstrate a potential change in the protein composition of SGs upon incorporation of mutant FUS. These findings advance the field of ALS and SG biology, thereby providing groundwork for future investigation.

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50

Burgdurff, Richard Belchior Klipp. "Mais tambor menos motor e a criação de canções." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/172924.

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Esse trabalho é o relato do processo de criação de 9 canções e uma vinheta para o conteúdo cultural Mais Tambor Menos Motor de Richard Serraria. Canção aqui quer avançar para além da noção de poesia na letra de música, nisso abarcando ainda formas diversas de como isso se apresenta e atentando para as fronteiras inexistentes entre diferentes expressões que convivem em proximidade como rap, slam poetry e texto recitativo. Tal conteúdo cultural sendo o oitavo na trajetória do referido cancionista, traz ainda a descrição da caminhada do poeta se aproximando e apropriando-se da música como forma de dar suporte à sua produção cancional. Canção é tida aqui como um objeto artístico e portanto político, capaz de refletir sobre a condição contemporânea propondo reflexões em sua potencialidade de disparar transformações sociais. Sob esse aspecto destaca-se a perspectiva de uma cancionística em consonância com o tambor sopapo, elemento identitário na atualidade já que marcante da contribuição negra para a construção do estado do Rio Grande do Sul no período colonial. Além disso, é destacada a ideia da intercancionalidade, a saber referência intertextual como elemento fundamental no processo de criação do cancionista, dividindo tal aspecto em duas frentes: literária e musical.
Este trabajo es la historia del proceso de creación de 9 canciones y una viñeta para el contenido cultural Mais Tambor Menos Motor de Richard Serraria. Canción aquí quiere ir más allá de la noción de la poesía en la lírica, todavía abrazando diferentes maneras de cómo se presenta y prestar atención a los límites inexistentes entre las diferentes expresiones que viven en las proximidades de rap, slam y el texto recitado. Dicho contenido cultural, siendo la octava en la trayectoria de dicho compositor, todavía lleva a pie la descripción del sendero del poeta con su apropiación de la música como una forma de apoyar su producción cancional. Canción se toma aquí como un objeto artístico y por lo tanto política, capaz de reflexionar sobre la condición contemporánea y proponer reflexiones sobre su potencial para desencadenar la transformación social. A este respecto es una cancionística en línea con el tambor sopapo, elemento de afirmación de la identidad hoy y del aporte negro a la construcción del estado de Rio Grande do Sul durante el período colonial. Además, se puso de relieve la idea de intercancionalidad, a saber referencia intertextual como un elemento clave en el proceso de creación del compositor, dividiendo este aspecto en dos frentes: literaria y musical.

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Dissertations / Theses on the topic 'RNP granule'

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