Dissertations / Theses on the topic 'Spatial regulations'
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Toriro, Percy M. "Food production, processing and retailing through the lens of spatial planning legislation and regulations in Zimbabwe: evidence from Epworth." Doctoral thesis, Faculty of Science, 2019. http://hdl.handle.net/11427/30336.
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The thesis investigates whether the Zimbabwe planning regulatory framework engages with urban food systems and whether those regulations and plans are appropriate to the lived experience in African cities particularly focusing on the poor through the lens of food. This is done by examining how food production, processing and retailing have been enhanced, constrained and regulated by urban planning laws and regulations and the administering professionals in the urban settlement of Epworth near Harare in Zimbabwe. Food is a basic need but has not been given prominence in planning discourses. The use of food as a lens through which to examine the appropriateness of planning practice, laws, and the general regulatory framework provides a useful opportunity to consider the impact of planning on livelihoods of the urban poor in the global South. This thesis also provides an opportunity to link the two distinct but complimentary disciplines of urban planning and urban food and contributes to knowledge on contemporary planning and food systems. Treating the two as separate and disconnected fields has created gaps and inconsistencies that manifest themselves in inappropriate regulations and plans thereby causing insecure and risky food systems. Using mixed research methods, the thesis concludes that the legislative framework engages food in a largely inappropriate way for several reasons. Firstly, the legislative framework was adapted from a Western context which differs significantly with that of the global South. Secondly the framework was enacted for a different time and context many years ago unlike the context prevailing now. Thirdly the inappropriateness of the governance framework has been exacerbated by the modernist values held by most planning professionals. A key finding of the thesis is that most planners do not support informal livelihoods; whilst they practice in a largely informal poverty-stricken environment, they aspire for a modern ‘world-class’ city environment. The planners also do not believe that they have a role in food systems planning. Meanwhile, they are busy making decisions that threaten the same food systems. The planning regulatory framework therefore requires amendment of the inappropriate clauses whilst positive clauses should be utilized.
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Ramblado, Carcenac Carole. "Reponses choroidiennes en microgravite reelle (vol spatial), simulee (suspension anti-orthostatique) et en hypergravite : regulations impliquant le recepteur 5-ht 2 c." Paris 6, 2001. http://www.theses.fr/2001PA066206.
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Une gravite alteree induit des variations volemiques et une redistribution des fluides corporels. Ainsi, au debut d'un vol spatial, une hypervolemie thoracocephalique s'etablit, puis, apres 1-2 jours, survient une hypovolemie adaptative. Dans ce travail, nous avons analyse l'effet de ces variations sur les plexus choroides (pc) qui produisent le liquide cephalo-rachidien (lcr), en etudiant les consequences d'une suspension anti-orthostatique (ao) a court (<3heures) et a long terme (>9jours), d'une hypergravite ou d'un vol spatial. La production de nucleotides cycliques (ampc et gmpc, messagers regulant la production de lcr) et l'expression du recepteur 5-ht 2 c ont principalement ete etudiees. En accord avec un profil d'hypersecretion, sans ouverture des jonctions intercellulaires, l'activite adenylatecyclase accrue, l'activite guanylate-cyclase (gc) diminuee et l'expression du recepteur 5-ht 2 c legerement diminuee suggerent que la production de lcr augmente lors de l'adaptation ao a court terme. L'activite gc et l'expression du recepteur 5-ht 2 c, significativement augmentees lors d'une adaptation plus longue (14 jours de suspension ao), temoignent en faveur d'une diminution de la production de lcr. En vol spatial (experience nasa), les taux basaux de gmpc sont augmentes, mais l'activite gc anp-dependante ne semble pas affectee. En hypergravite (2g, 3g), les productions d'ampc et de gmpc sont peu modifiees, malgre une reorganisation du pole apical. Des regulations serotoninergiques pourraient aussi etre impliquees dans la reponse a un sejour en microgravite reelle. Ces donnees ont confirme que les pc sont tres sensibles aux variations de gravite. Parallelement, l'expression de l'enzyme de conversion de l'angiotensine (ace) dans les pc a ete analysee lors de conditions de gravite alteree et apres deshydratation. Si l'ace n'est pas modifiee au debut d'une suspension ao, elle est diminuee a plus long terme, lors d'un vol spatial, en hypergravite et en deshydratation.
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Eriksson, Sara. "Landsbygdsutveckling i strandnära lägen : En studie av LIS som planeringsverktyg i Norrbotten." Thesis, Umeå universitet, Institutionen för geografi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185813.
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The purpose of this study was to investigate how the planning tool LIS, countryside development in areas close to shores has been applied in Norrbotten County. And what problems the municipalities experience in the planning process. Today's regulations for rural development in coastal locations have been criticized in investigations and by politicians for lacking geographical flexibility and that the planning tool isn’t adapted for sparsely populated areas. The study is a case study where the empirical evidence is mainly based on documents and investigations linked to rural development in coastal locations. The analysis has been carried out using broad thematic concepts. To get a greater understanding of how the planning tool is used in Norrbotten, interviews have been conducted with three municipalities with large rural areas. All those interviewed work with or have experience of the planning tool. The study shows that rural development in coastal locations has several problems with the enforcement and interpretation of the regulations. And that the planning tool itself does not contribute to rural development but that it can be seen as part of a larger context. However, two of the municipalities express that LIS is important to their municipalities to be able to offer attractive beach plots. A new report presented in December 2020, which aims to improve current regulations, has been received with some positive caution. The municipalities believe that the presented improvements are a step in the right direction towards a more geographically flexible regulatory framework. But that there are still major shortcomings in the enforcement of the regulations and that the municipalities need to have a greater influence in decisions regarding establishment in rural areas.
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Peyker, Anna. "Spatial regulation of Ras activity." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980142636.
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Smith, Elizabeth M. "Spatial and temporal regulation of IL4Rα expression." Doctoral thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/3117.
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Includes abstract.In this study, we generated a new mouse model, which allows both inducible and cell-specific deletion and reconstitution of IL-IL4Rα expression. This model has the potential to add a new dimension to our understanding of IL4Rα biology. This has been achieved by using the established Tet System (Goosen and Bujard, 1992) where the crossing of two complementary transgenic mouse lines enable the generation of the final double transgenic model. The first line expresses the transactivator, tTA, from the Tet-Off expression cassette driven by the Vav hemapoeitic specific promoter (Wiesner et al., 2005).
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Margrain, Thomas Hengist. "Recovery of spatial vision following intense light adaptation." Thesis, City University London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264755.
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Bird, Sarah Anne. "Spatial Regulation of MT1-MMP in Epithelial Cells." Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487203.
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Tube structures are fundamental in multicellular organisms and are found in many epithelial organs. Madine-Darby Canine Kidney (MOCK) epithelial cells are used as a model to study tubulogenesis as they form branching tubules in a 3-D type-l collagen gel upon stimulation with Hepatocyte Growth Factor (HGF). During this process, cells need to degrade the surrounding collagen matrix and they have been shown to primarily utilise the collagenase membrane-type I metalloproteinase (MTI-MMP, MMP-14) to achieve this. The aim of this thesis is to investigate the mechanisms regulating MTl-MMP during this process. We observed that MTlMMP preferentially localised to the apical surface of polarised MOCK cells cultured on type-I collagen. However, upon stimulation with HGF, a significant amount of MTI-MMP was detected on the basal surface. This localisation has a functional impact as cells degrade type-I collagen only upon HGF stimulation in 2-D culture. We hypothesise that MTl-MMP activity is spatially regulated in polarised MOCK cells, enabling enzyme activity to be higher at the growing tip of the tubule than atthe base. We also observed that MOCK cell attachment to collagen is required for MTl-MMP to localise to the basal surface. By analysing domain deletion mutants of MTI-MMP, it became clear that HGF-dependent localisation to the basal surface is catalytic domain/linker-I and hemopexin domain-dependent. Specifically, the MT-Loop C63pYAYlREG170 ), a unique sequence in the catalytic domain of all;ransmembrane-type MT-MMPs, is essential for basal localisation. Further characterisation of the MT-Loop region indicated that it also plays a critical role in the localisation of MTl-MMP in non-epithelial cells. COS-7 cells expressing the MT-Loop deletion mutant showed a significant reduction in collagen and gelatin degradation in 2-0 culture, even though the cell surface expression level and in vitro catalytic activity of this mutant was similar to full-length enzyme. Taken together, my research has revealed a novel mechanism that regulates MTl-MMP and hence tube formation of MOCK cells, which may be applicable to tubulogenesis in vivo.
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Wilfling, Florian. "The spatial organization and regulation of triacylglycerol synthesis." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-170796.
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Zhang, Yang. "A visualization interface for spatial pathway regulation data." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-237741.
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Data visualization is an essential methodology for bioinformatics studies. Spatial Transcriptomics(ST) is a method that aims at measuring the transcriptome of tissue sections while maintaining its spacial information. Finally, the study of biological pathway focuses on a series of biochemical reactions that take place in organisms. As these studies generate a large number of datasets, this thesis attempts to combine the ST’s data with pathwayinformation and visualize it in an intuitive way to assist user comprehension and insight.In this thesis, Python was used for integrating the dataset and JavaScript libraries wereused for building the visualization. The processing of ST pathway data together with the data visualization interface are the outcomes of this thesis. The data visualization can show the regulation of pathways in the ST data and can be accessed by modern browsers. These outcomes can help users navigate the ST and pathway datasets more effectively.Datavisualisering är en viktig del av bioinformatik. Spatial transkriptomik (ST) är en metod som mäter transkriptom, samtidigt som den behåller spatial information. Biologiskapathways å andrasidan fokuserar på biokemiska reaktioner som sker inom organismer. Dessa studier genererar mycket data, och denna avhandling försöker att kombinera ST-data med pathway information och få en intuitiv visualisering av det integrerade datat.I avhandlingen användes Python för att integrera datat och JavaScript bibliotek för attbygga visualiseringsverktyget. Avhandlingen resulterade i en metod för att integrera STdata och pathway information, samt ett visualiseringsverktyg för ovan nämnda information.Verktyget kan visa pathway regulationer i ST data och kan användas i moderna webbläsare.Forskningen resulterade i ett verktyg som kan hjälpa forskare att förstå ST och pathwaydata.
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Turaga, Rama Mohana Rao. "Spatial Resolution, Costs, and Equity in Air Toxics Regulation." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16236.
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Concern about environmental injustice has been driving the recent effort to characterize risks from exposures to air toxics at very fine spatial resolutions. However, few studies seek to understand the potential policy implications of regulating risks at increasingly finer spatial resolutions and the impact of resulting policies on distribution of risks. To address this gap, the broad question for this research is how could the choice of spatial resolution for regulation of risks from toxic air pollutants affect emission controls and the consequences thereof? This research develops a formal model of a hypothetical decision maker choosing emission controls within a risk-based regulatory framework. The model suggests that optimal controls on air toxics emissions vary depending on the spatial resolution chosen to regulate risks; net social costs are non-decreasing as one regulates at finer and finer spatial resolutions.
An empirical application of the model using air toxic emission data for Escambia and Santa Rosa Counties in Florida demonstrates the sensitivity of optimal emissions to spatial resolution chosen for regulation. The research then investigates the equity implications of regulating at different spatial resolutions with regard to the spatial distribution of cancer risks. The empirical results indicate that regulation at finer spatial resolutions could involve a tradeoff between costs and equitable distribution of risks. For example, at a threshold cancer risk of 100 in a million, regulating at census block level resolution could be twice as costly as regulating at census tract resolution while reducing the maximum individual risk by almost half. Further, regulation at finer spatial resolutions might not address environmental injustice by itself unless such concerns are more explicitly incorporated into emission control decisions. Finally, this research shows that spatial resolution at which air toxics risks are regulated could matter in predictable ways even after taking into account the uncertainties that the decision maker faces.
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Forster, Rebecca Claire. "Spatial and temporal regulation of ER-to-Golgi transport." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404311.
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Grimsey, Neil Justin. "Temporal and spatial regulation of lipin 1 and 2." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611174.
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Iozzi, Alberto. "Essays on regulation : theory and practice." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313959.
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Cooper, Timothy J. "Investigating the spatial regulation of meiotic recombination in S. cerevisiae." Thesis, University of Sussex, 2018. http://sro.sussex.ac.uk/id/eprint/74309/.
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Zhang, Yong. "Spatial regulation of motility in the social bacterium Myxococcus xanthus." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX22110.
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Tous les organismes, les animaux, les plantes et les microbes, sont composés de cellules polarisées, en affichant un positionnement asymétrique des organites sub-cellulaires ou des structures. Le contrôle de polarité a été étudié chez les eucaryotes pendant une longue période, et a été montré pour être impliqués dans de nombreux processus physiologiques, tels que l'embryogenèse, le cancer métastatique et les maladies dégénératives des neurones. Chez les procaryotes, des études de polarité ne sont apparues récemment avec le développement de la microscopie à fluorescence sensibles. Ces études ont révélé que les cellules procaryotes sont en fait très organisé et une masse croissante de la littérature a montré que les cellules bactériennes également utiliser des radeaux lipidiques, courbure membranaire, la paroi cellulaire et un cytosquelette complexe pour diriger le positionnement spécifique de structures subcellulaires.Petites GTPases de la superfamille Ras sont des éléments réglementaires polarisation répandue chez les eucaryotes. Malgré l'existence depuis longtemps de ces petites GTPases dans les génomes procaryotes, leur fonction a jamais été étudiée. Pendant ce travail de thèse, nous avons trouvé, pour la première fois, qu'une petite GTPase, MglA et de sa protéine apparentée Activation GTPase (GAP) MglB, directe une dynamique axe antéro-postérieur à la motilité directe en forme de tige deltaproteobacterium Myxococcus xanthus. Dans ce processus, MglA s'accumule dans son état lié au GTP au niveau du pôle leader de cellules, en activant les machineries motilité. Ce schéma de localisation est maintenue par MglB, qui localise le pôle opposé, le blocage de l'accumulation MglA à ce pôle à travers son activité GAP. Remarquablement, les deux protéines passer leur localisation synchrone, ce qui correspond à un changement dramatique dans la direction du mouvement cellulaire (inversion). Ce commutateur est réglementé par un système chimiosensoriels-like, Frz. Dans une deuxième partie de ce travail, nous avons identifié un régulateur de protéine de réponse, RomR qui est essentiel pour le regroupement polaire de MglA. Interdépendances complexes entre la localisation RomR, MglA et MglB indiquent que ces protéines pourraient constituer un complexe de polarité dynamique de trois protéines qui reçoit Frz de signalisation pour passer l'axe de polarité. En conclusion, les résultats de ce travail de thèse suggère que M. xanthus intégré un module de polarité eucaryotes-like (MglAB) dans un procaryote spécifique (Frz) réseau de signalisation pour réguler sa motilité. Une telle réglementation est distincte sous forme de petites protéines G des règlements, qui sont généralement couplés à la protéine G récepteurs couplés (GPCR) chez les eucaryotes. Enfin, ce travail ouvre la voie pour comprendre comment la réglementation seule la motilité cellulaire sont intégrés pour générer des comportements commandés multicellulaires donnant naissance à des structures primitives de développement, par exemple, la morphogenèse du corps fructifères. D'autre part, ce travail fournit également un exemple d'analyser les étapes évolutives donnant lieu à des réseaux de signalisationAll organisms, animals, plants and microbes, are composed of polarized cells, displaying asymmetric positioning of sub-cellular organelles or structures. Polarity control has been studied in eukaryotes for a long time, and has been shown to be involved in many physiological processes, such as embryogenesis, cancer metastasis and neuron degenerative diseases. In prokaryotes, polarity studies only emerged recently with the development of sensitive fluorescent microscopy. These studies revealed that prokaryotic cells are in fact highly organized and a growing body of literature has shown that bacterial cells also use lipid rafts, membrane curvature, the cell wall and a complex cytoskeleton to direct the specific positioning of subcellular structures.Small GTPases of the Ras superfamily are widespread polarization regulatory elements in eukaryotes. Despite the long known existence of such small GTPases in prokaryotic genomes, their function has never been studied. During this thesis work, we found, for the first time, that a small GTPase, MglA and its cognate GTPase Activating Protein (GAP) MglB, direct a dynamic anterior- posterior axis to direct motility of the rod-shaped deltaproteobacterium Myxococcus xanthus. In this process, MglA accumulates in its GTP-bound state at the leading cell pole, activating the motility machineries. This localization pattern is maintained by MglB, which localizes at the opposite pole, blocking MglA accumulation at this pole through its GAP activity. Remarkably, both proteins switch their localization synchronously, which correlates with a dramatic change in the direction of cell movement (reversal). This switch is regulated by a chemosensory-like system, Frz. In a second part of this work, we identified a response regulator protein, RomR which is essential for the polar clustering of MglA. Intricate localization interdependencies between Romr, MglA and MglB indicate that these proteins might constitute a dynamic three-protein polarity complex that receives Frz-signaling to switch the polarity axis. In conclusion, the results from this thesis work suggest that M. xanthus integrated a eukaryotic-like polarity module (MglAB) into a prokaryotic- specific (Frz) signaling network to regulate its motility. Such regulation is distinct form small G- protein regulations, which are generally coupled to G-protein coupled receptors (GPCRs) in eukaryotes. Finally, this work paves the way to understand how single cell motility regulations are integrated to generate ordered multicellular behaviors giving rise to primitive developmental structures, for example fruiting body morphogenesis. On the other hand, this work also provides an example to analyze the evolutionary steps giving rise to signaling networks
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Brasebin, Mickaël. "Les données géographiques 3D pour simuler l’impact de la réglementation urbaine sur la morphologie du bâti." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1006/document.
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Les données géographiques 3D sont de plus en plus courantes et modélisent de manières variées le territoire. Elles sont souvent utilisées pour mieux comprendre la ville et ses phénomènes sous-jacents en intégrant de nombreuses informations (environnementales, économiques, etc.) pour l'appui à l'aménagement du territoire. À l'échelle locale, le plan local d'urbanisme (PLU) décrit les connaissances régulant le développement urbain, incluant des contraintes tri-dimensionnelles (par exemple : hauteur maximale d'un bâtiment ou surface de plancher) que doivent respecter les nouveaux bâtiments. Ces contraintes sont rédigées dans un format textuel, difficile de compréhension pour le non-initié et dont l'interprétation sur un territoire donné est complexe. L'objectif de cette thèse est de montrer comment les données géographiques 3D permettent d'exploiter les règlements locaux d'urbanisme à travers deux usages : la vérification de règles d'urbanisme et la proposition de configurations bâties. Notre méthodologie s'appuie sur une modélisation de l'espace urbain, représentant les objets pertinents mentionnés dans les règlements, support d'une formalisation des règles avec le langage OCL. La proposition de configurations bâties est réalisée grâce à une méthode d'optimisation basée sur un recuit simulé trans-dimensionnel et une technique de vérification du respect des règles3D geographic data are very frequent and represent territories in various ways. Such data are often used to better understand cities and their underlying phenomena by integrating different information (environmental, economic, etc.) to support urban planning. On a local scale, the French Local Urban Plan (PLU) describes constraints that regulate the urban development, notably through tri-dimensional constraints (for example by defining a maximal height or by limiting built area) that new buildings must respect. These constraints are compiled in a textual format. They are difficult to understand for non experts and their impact for a given territory is complex to assess. The aim of this thesis is to demonstrate how 3D geographic data enable the exploitation of local urban regulation constraints through two different uses: the verification of the respect of constraints and the generation of building configurations. Our method relies on a model of the urban environment, representing relevant objects according to regulations. This model supports the formulation of the constraints with the OCL language. The generation of building configurations is processed by an optimization method based on a trans-dimensional simulated annealing relying on a rule checker
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Elineni, Kranthi Kumar. "Regulation of Cell Adhesion Strength by Spatial Organization of Focal Adhesions." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3088.
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Cell adhesion to extracellular matrix (ECM) is critical to various cellular processes like cell spreading, migration, growth and apoptosis. At the tissue level, cell adhesion is important in the pathological and physiological processes that regulate the tissue morphogenesis. Cell adhesion to the ECM is primarily mediated by the integrin family of receptors. The receptors that are recruited to the surface are reinforced by structural and signaling proteins at the adhesive sites forming focal adhesions that connect the cytoskeleton to further stabilize the adhesions. The functional roles of these focal adhesions extend beyond stabilizing adhesions and transduce mechanical signals at the cell-ECM interface in various signaling events. The objective of this research is to analyze the role of the spatial distribution of the focal adhesions in stabilizing the cell adhesion to the ECM in relation to cell's internal force balance. The central hypothesis was that peripheral focal adhesions stabilize cell adhesion to ECM by providing for maximum mechanical advantage for resisting detachment as explained by the membrane peeling mechanism. Micropatterning techniques combined with robust hydrodynamic shear assay were employed to test our hypothesis. However, technical difficulties in microcontact printing stamps with small and sparse features made it challenging to analyze the role of peripheral focal adhesions in stabilizing cell adhesion. To overcome this limitation, the roof collapse phenomenon in stamps with small and sparse features (low fill factor stamps) that was detrimental to the reproduction of the adhesive geometries required to test the hypothesis was analyzed. This analysis lead to the valuable insight that the non-uniform pressure distribution during initial contact caused by parallelism error during manual microcontact printing prevented accurate replication of features on the substrate. To this end, the template of the stamp was modified so that it included an annular column around the pattern zone that acted as a collapse barrier and prevented roof collapse propagation into the pattern zone. Employing this modified stamp, the required geometries for the cell adhesion analysis were successfully reproduced on the substrates with high throughput. Adhesive areas were engineered with circular and annular patterns to discern the contribution of peripheral focal adhesions towards cell adhesion strength. The patterns were engineered such that two distinct geometries with either constant adhesive area or constant spreading area were obtained. The significance of annular patterns is that for the same total adhesive area as the circular pattern, the annular pattern provided for greater cell spreading thereby increasing the distance of the focal adhesions from the cell's center. The adhesion strength analysis was accomplished by utilizing hydrodynamic shear flow in a spinning disk device that was previously developed. The results indicate that for a constant total adhesive area, the annular patterns provide for greater adhesion strength by enhancing cell spreading area and providing for greater moment arm in resisting detachment due to shear. The next examination was the effect of the cell's internal force balance in stabilizing the cell adhesion. The working hypothesis was that microtubules provide the necessary forces to resist the tensile forces expressed by the cell contractile machinery, thereby stabilizing cell adhesion. Since microtubule disruption is known to enhance cell contractility, its effect on the cell adhesion strength was examined. Moreover, the force balance in cells was altered by engineering adhesive areas so that the cells were either spherical or completely spread and then disrupted microtubules to understand the significance of the force balance in modulating the cell adhesion strength. The results indicated that disruption of microtubules in cells on adhesive islands resulted in a 10 fold decrease in adhesion strength compared to untreated controls whereas no significant change was observed in completely spread cells between treated and untreated controls. This is in surprising contrast to the previous contractility inhibition studies which indicate a less pronounced regulation of adhesion strength for both micropatterned and spread cells. Taken together, these findings suggest that the internal force balance regulated by cell shape strongly modulates the adhesion strength though the microtubule network. In summary, this project elucidates the role of peripheral focal adhesions in regulating the cell adhesion strength. Furthermore, this study also establishes the importance of the internal force balance towards stabilizing the cell adhesion to the ECM through the microtubule network.
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Gurd, Amy M. "Imagined ruralities and the spatial regulation of sex work in Queensland." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/115070/1/115070_6336272_amy_gurd_thesis.pdf.
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This research examines the importance of space as a socially constructed concept in political discourse on sex work. In particular, this thesis analyses the extent to which the rural imaginary, and its related values of Christian conservatism, and monogamous heterosexual families, has influenced the creation of the brothel exemption provision in state sex work legislation for small rural towns in Queensland, Australia. The findings of the research indicate that rural and urban political attitudes to sex work are inherently similar, ranging from a moral threat, to a public nuisance or to a grudging acceptance. The thesis argues that the concerns raised by rural political representatives regarding sex work in rural contexts are most indicative of their anxieties about the transformation of 'traditional' rural spaces to modern urban spaces. Sex work thus becomes an exemplar of the disruption that the urban can make to the rural.
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Ofori, Benjamin O. "The Urban Street Commons Problem: Spatial Regulation in the Urban Informal Economy." Ohio : Ohio University, 2007. http://www.ohiolink.edu/etd/view.cgi?ohiou1180940316.
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Shaik̲h̲, Naṣīruddīn. "Spatial regulation of carbohydrate metabolism in a monocotyledonous leaf (Hordeum vulgare L.)." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301274.
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Weston, Cathryn A. "The spatial and temporal regulation of the monomeric G protein, Ras 1." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57576/.
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A vast array of cellular processes are controlled by the highly conserved guanine nucleotide-regulated molecular switches, such as Ras. The spatial and temporal regulation of Ras signalling, both positively, through the action of guanine nucleotide exchange factors (GEFs) and negatively, via interaction with GTPase activating proteins (GAPs) is critical to maintain cell viability. Due to the presence of multiple Ras isoforms, regulatory proteins and effectors, the study of Ras signalling in higher eukaryotes is technically challenging. Fission yeast provides a simple system in which to study Ras signalling containing a single Ras homologue (Ras1) that modulates two distinct processes. Ras1 signalling is terminated through GTP-hydrolysis accelerated by the action of a GAP, Gap1. This thesis describes the development of a quantitative FRET assay to visualise the dynamics of Ras1 activity within single cells. Using this reporter, in combination with a variety of other quantitative techniques, the role of the negative regulator during signal transduction was explored. These results highlighted an important difference between the requirement for GTPhydrolysis during signal propagation. Finally, use of the FRET reporter revealed an alternative G protein state, within the Ras1 activation cycle. These data question the accepted models of G protein signal propagation and prompt further investigation into the roles of GTP-hydrolysis in signal transduction. Several positive regulators of Ras1 have previously been described in fission yeast. These proteins have been proposed to direct signalling via the different Ras1 effectors. Using quantitative image analysis and pheromoneresponsive reporter strains, this thesis presents data to suggest that it is not simply a one-activator-one-effector response. Further, the role of the previously uncharacterised, scaffold protein, Ral2 in mediating signal transduction is also investigated. Finally the possibility that the heterotrimeric G protein, Gpa1 can directly activate MAPK signalling to provide a pheromone-sensing mechanism within fission yeast is discussed.
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Mohan, Abhinav. "ROLE OF E-CADHERIN FORCE IN THE SPATIAL REGULATION OF CELL PROLIFERATION." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4659.
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Cell proliferation and contact inhibition play a major role in maintaining epithelial cell homeostasis. A hallmark of epithelial cells is strong cell-cell junctions. These junctions include E-Cadherin, a type of adherens junction that is critical for both barrier function and contact inhibition. Prior experiments by other groups have shown that adherens junctions are subject to mechanical tension. Externally applied forces (e.g. stretch) results in changes in E-Cadherin forces that coordinate proliferation. My current work tests the hypothesis that E-Cadherin forces mediate the spatial regulation of cell proliferation even in the absence of externally applied forces.
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Dun, Alison. "Spatial and temporal control of regulated exocytosis by protein and lipid interactions." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8087.
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Cellular communication requires the transport of chemical messengers between intracellular compartments and from cell to cell. The regulated exocytosis of a secretory vesicle at the plasma membrane involves the merger of two bilayers, with markedly different lipid composition, within a millisecond time scale. The spatial and temporal control of the protein and lipid complement at these fusion sites is essential. A highly conserved family of proteins are known to drive this fusion event; SNAP-25 and syntaxin-1 (t-SNAREs) associate at the plasma membrane in a 1:1 stoichiometry to provide a binding site for the vesicle-membrane protein synaptobrevin (v-SNARE). The formation of this complex and subsequent fusion requires accessory proteins for efficient calcium-triggered exocytosis; which of these proteins facilitate the initial attachment of vesicle to the plasma membrane prior to fusion is still under debate. Specific sites for vesicle fusion have been proposed and the organisation of lipids and proteins at these fusion sites has been extensively investigated with limited spatial and temporal resolution; however the presence of raft-forming lipids at these sites as well as the arrangement of SNARE proteins at the molecular level is still under contention. The data presented within this thesis aims to elucidate the protein and lipid environment at the fusion site using super-resolution microscopy and advanced vesicle tracking. Under diffraction-limited microscopy the t-SNAREs are visualised as 200 nm homogenous clusters; however I have used single molecule localisation microscopy to reveal a more complex heterogeneous molecular arrangement. Quantification of lipid order exclusively at the plasma membrane provided insight into the influence of cholesterol-induced lipid arrangement on SNAP-25 localisation. In addition the t-SNARE interaction was investigated using TCSPC-FLIM identifying two lipid-order-dependent conformations in distinct clusters at the plasma membrane. Extensive vesicle tracking at optimum sampling rates demonstrated the ‘sampling’ behaviour of LDCVs and allowed characterisation of vesicle fusion sites. In summary I find that vesicles exhibit preference for residence and probably fusion at regions of plasma membrane with a low t-SNARE density; these proteins appear to exert control over exocytosis by adopting alternative conformations that are under cholesterol-induced regulation.
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Wilfling, Florian [Verfasser], and Stefan [Akademischer Betreuer] Jentsch. "The spatial organization and regulation of triacylglycerol synthesis / Florian Wilfling. Betreuer: Stefan Jentsch." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2013. http://d-nb.info/1052779557/34.
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Mackin, Nancy A. "The spatial and temporal regulation of morphogenesis in the budding yeast Saccharomyces cerevisiae." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2006. http://proquest.umi.com/login?COPT=REJTPTU0NWQmSU5UPTAmVkVSPTI=&clientId=3739.
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Rogers, Louisa Ann. "Exploring the spatial and temporal regulation of lignification in three ectopic lignification mutants." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401106.
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Georgala, Petrina A. "Spatial and temporal regulation of cerebral cortex development by the transcription factor pax6." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4816.
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Lamina formation in the developing cortex requires precise generation, migration and differentiation of cortical neurons. Cortical projection neurons originate from progenitors of the embryonic dorsal telencephalon. The transcription factor Pax6 is expressed in apical progenitors (APs) throughout corticogenesis in a rostro-lateralhigh to caudo-mediallow gradient. The current studies focus on elucidating the spatial and temporal role of Pax6 in cortical development. I first analysed the cortex of PAX77 transgenic mice that overexpress Pax6 in its normal domains of expression. I show that Pax6 overexpression acts cell-autonomously to reduce the proliferation of late cortical progenitors specifically, resulting in the formation of thinner superficial layers in the PAX77 cortex. Increased levels of Pax6 lengthen the cell cycle of APs and drive the system towards neurogenesis. These effects are specific to late stages of corticogenesis, when superficial layer neurons are normally generated, in cortical regions that express Pax6 at the highest levels. The number of superficial layer neurons is reduced in postnatal PAX77 mice, while radial migration and lamina specification of cortical neurons are not affected by Pax6 overexpression. Then, Pax6 was conditionally inactivated in cortical progenitors at mid- or late-stages of corticogenesis by using a tamoxifen-inducible Emx1-CreER line. I report a novel requirement of Pax6 for continuous suppression of ventral fates and concurrent maintenance of an appropriate dorsal identity in cortical progenitors. Pax6 ablation at either mid- or late-stages of corticogenesis increases the proliferation of late cortical progenitors at all levels across the rostral-caudal axis. In the absence of Pax6 from mid-corticogenesis, late-born neurons are severely under-represented and misspecified in superficial layers of the mutant cortex. Notably, Pax6 inactivation during late corticogenesis also affects superficial laminar fate; although the numbers of late-born cortical neurons are not severely affected in superficial layers of the mutant cortex, substantial numbers of late-born cells fail to migrate to appropriate laminar positions and accumulate in the ventricular zone (VZ) of the postnatal mutant cortex. Collectively, these gain- and loss-of-function studies suggest that disruption of Pax6 levels during different developmental time points leads ultimately to impaired formation of superficial cortical layers but through different cellular and molecular mechanisms.
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Müller, Paul Markus [Verfasser]. "Temporal and Spatial Regulation of Rho GTPase Activity and Specificity / Paul Markus Müller." Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1196803080/34.
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Reichert, S. "The dynamic temporal and spatial regulation of BMP signalling during early vertebrate development." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1420539/.
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During embryonic development multipotent cells are specified to give rise to the different tissues of the body. This process depends on a tightly controlled network of signalling pathways. Importantly, tissues, which require differential activity of these pathways, can be induced in close proximity, thus suggesting an intricate spatial and temporal control of pathway activation. One of the pathways crucial for tissue specification is the bone morphogenetic protein (BMP) signalling pathway. Its role in the patterning of the ectoderm is well understood during gastrulation but unclear for later stages of development. Using zebrafish and Xenopus as model organisms, I investigated the spatial and temporal control of BMP activity after gastrulation at the border of the neural plate as progenitor cells emerge that give rise to cell types such as melanocytes and smooth muscle cells, as well as the olfactory epithelium and the lens. I identified new players that regulate the formation of distinct domains of BMP signalling and thereby enable the specification of adjacent tissues with different requirements for BMP activity. Previously, Snw1 was identified as a crucial factor for neural crest specification during development. Overexpression and depletion of Snw1 in Xenopus and zebrafish embryos leads to a loss of the neural crest cell population. Snw1 was identified as a regulator of BMP activity at the neural plate border, but not as a core component of the pathway downstream of the receptor. Snw1 is involved in a step between transcription and expression of the BMP ligands and since depletion of Snw1 in zebrafish increases bmp2b ligand transcription but prevents expression of the protein. I have further dissected the function of Snw1 and shown that Snw1 is in a complex with components of splicing machinery, as well as several chromatin remodeling and transcriptional elongation factors. I have used RNAseq to identify additional Snw1 targets.
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Cox, Carissa. "Spatial Patterns in Development Regulation: Tree Preservation Ordinances of the DFW Metropolitan Area." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc84194/.
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Land use regulations are typically established as a response to development activity. For effective growth management and habitat preservation, the opposite should occur. This study considers tree preservation ordinances of the Dallas-Fort Worth metropolitan area as a means of evaluating development regulation in a metropolitan context. It documents the impact urban cores have on regulations and policies throughout their region, demonstrating that the same urban-rural gradient used to describe physical components of our metropolitan areas also holds true in terms of policy formation. Although sophistication of land use regulation generally dissipates as one moves away from an urban core, native habitat is more pristine at the outer edges. To more effectively protect native habitat, regional preservation measures are recommended.
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Nguedam, Ntouko Clarisse. "Gouvernance et institutions dans les décisions d'investissement privé dans les pays en développement." Thesis, Clermont-Ferrand 1, 2012. http://www.theses.fr/2012CLF10383.
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Cette thèse analyse l’impact des facteurs institutionnels et de la gouvernance sur l’investissement privé dans les pays en développement. La problématique de la « bonne gouvernance » et de l’amélioration de la qualité institutionnelle notamment dans les pays en développement sont au coeur des préoccupations de la communauté internationale. Pour autant, il n’existe pas un cadre institutionnel et un système de gouvernance unique et optimal qui s’imposeraient de manière exogène à tous les pays, car les facteurs culturels, historiques et anthropologiques modèlent la qualité des institutions et le mode de gouvernance. En effet, si les pays peuvent avoir un objectif commun, celui d’un cadre institutionnel permettant notamment de garantir la viabilité et la crédibilité du climat d’investissement, ils démarrent tous de points différents, marqués par des caractéristiques propres.Ces facteurs nous emmènent à privilégier une approche relativiste et non normative de la qualité des institutions et de la gouvernance. Cependant,tous les cadres institutionnels ne se valent pas. Certaines configurations institutionnelles accroissent l’incertitude et l’irréversibilité de l’investissement. Nos analyses placent le déficit de gouvernance et la faiblesse des institutions au cœur de la problématique de l’incertitude et de l’irréversibilité de l’investissement dans les pays en développement. Nous adoptons dans cette thèse une démarche plurielle consistant en une analyse macroéconométrique qui permet d’apprécier le comportement de l’investissement au niveau agrégé, et une analyse microéconométrique qui a l’intérêt de prendre en compte l’hétérogénéité des comportements d’investissement des entreprises. Un accent particulier est porté à l’Afrique subsaharienne qui est la région ayant le plus faible taux d’investissementThis thesis analyzes the impact of governance and institutions on private investment in developing countries. "Good governance" and institutional quality especially in developing countries are of great concern to the international community. However, there is no unique and optimal institutional framework and governance system which can be set up in all countries independently to their cultural, historical and anthropological characteristics. Indeed, if all countries can share a common objective which consists of an institutional framework, able to ensure the sustainability and credibility of the investment climate, they will all start from different points with specific characteristics. These factors lead us to favor a non normative approach of the quality of institutions and governance. However, some institutional framework increases uncertainty and irreversibility ofinvestment. In this thesis, we consider weak institutions and poor governance as the main sources of uncertainty and irreversibility of investment indeveloping countries. We use a macroeconometric approach which analyses the investment behavior at the aggregate level, and a microeconometric approach which takes into account the heterogeneity of the investment behavior of firms. An emphasis is put on sub-Saharan African countries that have the lowest private investment rate
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Dantas, Ney de Brito. "Chaos in the drawing room : image making and image breaking in the experience of urban regulation in Recife." Thesis, Open University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298988.
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Li, Deyu. "Spatial and temporal regulation of mitotic progression by the spindle checkpoint in Drosophila melanogaster." Thesis, University of Newcastle Upon Tyne, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491836.
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The spindle assembly checkpoint is a cell-cycle surveillance system which ensures the mother cell equally and faithfully separates its replicated DNA contents into two daughter cells before the onset of anaphase. Mad2, BubRl and Cdc20 (Fzy in Drosophila melanogaster) are all kinetochore proteins which dynamically turnover on and off the mitotic kinetochores. It is believed that these proteins are forming a diffusible kinetochore anaphase inhibitory signal for spindle checkpoint function, inhibiting APC/C activity in order to delay the metaphase-anaphase transition (Musacchio and Salmon, 2007). APC/C is an E3 ubiquitin ligase. It ubiquitinates numbers of cell cycle regulating proteins, such as Cyclin B and Securin, and allows them to be targeted by proteasomes for destruction (Peters, 2006). However, the mechanism of the spatial and temporal interaction of these checkpoint proteins (Mad2, BubRl and Cdc20/Fzy) on kinetochores, and how they assemble to form this inhibitory signal remains unclear.
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Fenstermacher, Sara. "From nucleus to axon: Spatial regulation of bclw mRNA promotes neurotrophin-dependent axon survival." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17467330.
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During development, dorsal root ganglion (DRG) neurons depend on target-derived neurotrophins to establish a functional circuit capable of conveying sensory information to the central nervous system. Neurotrophins signal from the periphery via dynein-dependent retrograde transport of signaling endosomes to activate a nuclear transcriptional response critical for neuronal survival. Importantly, neurotrophins support the health of the entire DRG neuron, but it is not well understood how neurotrophins specifically function to promote survival of axons. Previous research demonstrated that target-derived neurotrophins induce expression of the anti-apoptotic Bcl2 family member, Bclw, and in vivo studies demonstrate that Bclw is a critical survival factor for sensory axons. Here we describe multi-step regulation of bclw mRNA from the nucleus to the axon to support the health and long-term maintenance of axons. We find that neurotrophins induce transcription of bclw mRNA, which is rapidly transported to axons. There it is locally translated to prevent caspase-dependent apoptosis and axon degeneration. We identify the RNA-binding protein splicing factor proline-glutamine rich (SFPQ) as a critical regulator that specifically interacts with bclw mRNA. SFPQ is required for nuclear export of bclw mRNA and for generating an axonal pool of bclw mRNA. Interestingly, we find that SFPQ binds and regulates additional mRNAs also required for axonal survival. Therefore we propose that SFPQ orchestrates an RNA regulon for coordinated regulation of functionally-related mRNAs including, bclw and laminb2, and thereby enables neurotrophin-dependent axonal health. Lastly, to investigate neurotrophin regulation of bclw translation in axons we describe development of a novel tool called spaceSTAMP. SpaceSTAMP allows for drug-dependent labeling of newly synthesized protein within distinct cellular compartments for both live cell imaging and biochemical analysis. We believe spaceSTAMP will be a rigorous method for studying local protein synthesis that will also provide critical information about the functional significance for localized translation in axons. Together, these studies demonstrate that spatial regulation of bclw mRNA mediates neurotrophin-dependent axonal viability and contribute towards our understanding of how neural circuits are established and maintained throughout life.Medical Sciences
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Drummond, Mike. "Spatial Regulation of the Polarity Protein aPKC During Asymmetric Cell Division of Drosophila Neuroblasts." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19225.
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The Par complex protein, atypical protein kinase C (aPKC), plays an instrumental role in diverse cell polarities. aPKC is able to restrict substrate localization through a phosphorylation-induced cortical exclusion mechanism, allowing for the generation of molecularly distinct cortical domains. Thus, controlling the localization of aPKC is central to Par-mediated polarity but the mechanism by which aPKC is polarized remains poorly understood. In this dissertation I investigated the restriction of aPKC to the apical cortex of Drosophila neural stem cells, neuroblasts, as these cells dynamically polarize aPKC through repeated asymmetric cell divisions. The polarity created through aPKC phosphorylation must be tightly regulated in order to ensure proper balance between self-renewal and differentiation.
To begin, I investigated whether or not aPKC’s so called ‘maturation’ by PDK1 phosphorylation is required for aPKC activity and localization. We found that aPKC’s phosphorylation by PDK1 is required for both polarity and full activity. An aPKC containing an unphosphorylatable activation loop mutation localizes symmetrically around the cortex in a manner independent of its binding partner, Par-6, suggesting that aPKC could interact with the cortex by an unknown mechanism.
To investigate how aPKC is able to localize to the cortex independent of Par-6, I used an in vivo structure function analysis of domains within aPKC, accompanied by biochemical approaches. I identified a necessity for the aPKC C1 domain for binding to the neuroblast cortex. This interaction is mediated by negatively charged phospholipids. Neither aPKC interaction, with phospholipids or Par-6, is sufficient to restrict aPKC to the apical cortex. Thus, aPKC polarization utilizes a dual interaction mechanism that takes advantage of both protein-lipid and protein-protein interactions, and proper control of each of these signals is required to prevent neuroblast division defects. One interaction, mediated by the C1, is a general cortical targeting mechanism, whereas the other specifies polarization mediated by Par complex interactions. We conclude that a conformational change induced by these interactions activates aPKC’s catalytic activity, thereby coupling localization and activity.
This dissertation includes unpublished co-authored material.
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Hueschen, Christina Lynn. "Building the Mitotic Spindle| Spatial Regulation and Function of Force at Microtubule Minus-Ends." Thesis, University of California, San Francisco, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13423508.
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Each time a cell divides, the microtubule cytoskeleton self-organizes into the metaphase spindle: an ellipsoidal steady-state structure that holds its stereotyped shape despite microtubule turnover and internal stresses. This ellipsoidal architecture, in which microtubule minus-ends are focused into two poles, is essential to the spindle’s function of accurately segregating chromosomes. In this work, I ask how the spindle forms and holds its steady-state shape. I report that the molecular motor dynein and the microtubule binding-protein NuMA are essential for mammalian spindles to reach and hold a steady-state geometry. In their absence, the kinesin-5 Eg5 powers a turbulent microtubule network that can drive flow of cytoplasmic organelles and whole-cell movement. Dynein and NuMA were previously known to be essential for spindle pole formation, but we did not know their contribution to shape stabilization at the whole-spindle scale—nor did we know how and where they pull on microtubules to build poles. Using quantitative live imaging and laser ablation, I show that dynein pulls specifically on microtubule minus-ends, rapidly transporting them towards poles. Dynein localization to microtubule minus- ends depends on NuMA, which recruits the dynein adaptor dynactin to minus-ends. Contrary to previous models, NuMA localization to minus-ends is independent of dynein and involves a C-terminal region outside its canonical microtubule-binding domain. Thus, NuMA serves as a mitosis-specific minus-end cargo adaptor, targeting dynein activity to minus-ends to cluster spindle microtubules into poles. This microtubule end-clustering compacts the spindle microtubule network to a defined geometry and suppresses network turbulence, maintaining a steady-state spindle shape over long timescales.
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Groocock, Lynda M. "Role of mto2 in temporal and spatial regulation of cytoplasmic microtubule nucleation in Schizosaccharomyces pombe." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/3970.
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The microtubule [MT] cytoskeleton of S. pombe is a highly dynamic network of filaments that facilitates intracellular transport, determines cell polarity and plays an essential role in chromosome separation during mitosis. In fission yeast, MTs are nucleated in a temporally and spatially regulated manner from sites called Microtubule Organising Centres [MTOCs], through the activity of both the g-tubulin complex [g-TuC] and the Mto1/2 complex. The Mto1/2 complex determines the localisation of the g-TuC at MTOCs, which change throughout the cell cycle. As cells enter mitosis the cytoplasmic array of MT bundles depolymerise. They are replaced by the intranuclear mitotic spindle and cytoplasmic spindle pole bodyderived astral MTs that in turn give way to the formation of the post-anaphase array. Although much is known about the properties of each type of MT array, the mechanism by which the timing of MT nucleation at different MTOCs is regulated over the cell cycle remains unclear. In the Mto1/2 complex, Mto1 is thought to provide the primary interaction with the g-TuC, and Mto2 functions by reinforcing this interaction. Due to the lack of structural information for the Mto1/2 complex, the molecular mechanism of Mto1/2- mediated assembly of the g-TuC at MTOCs is unknown. The aim of my study is to investigate the possibility that the Mto1/2 complex is able to promote g-TuC assembly by forming a direct template. In addition, I will attempt to determine the molecular role of Mto2 within the Mto1/2 complex and examine ways in which regulation of Mto2 may influence the function the Mto1/2 complex at specific MTOCs. As part of the investigation into the mechanism of Mto2 function, an in vitro analysis of recombinant protein demonstrated that in the absence of Mto1, purified Mto2 is able to self-interact as a tetramer. I have confirmed this interaction in vivo and have also shown that Mto2 forms a dimer as cells enter mitosis. However, in the context of an Mto1/2 complex the significance of the change in Mto2 oligomeric state remains unknown. Hydrodynamic analysis of a truncated form of the Mto1/2 complex suggests that it may form a heterotetramer, a hypothesis which is consistent with the equimolar levels of Mto2 and Mto1 protein within the cell. This information provides some structural insight as to how the Mto1/2 complex may interact with the g-TuC at MTOCs. Further analysis of the Mto1/2 complex revealed that in vivo, the Mto1-Mto2 interaction is disrupted during mitosis. This was found to correlate with the hyperphosphorylation of Mto2, which occurs as cells enter mitosis. Subsequently, an in vitro kinase assay demonstrated that phosphorylation of the Mto1/2 complex reduces the stability of the complex. Mass spectrometry techniques and sequence conservation were used to identify several phosphorylated residues within Mto2 and the ability of these mutants to bind to Mto1 was analysed in vivo and in vitro. In summary, in this study I have uncovered a mechanism which allows fission yeast cells to regulate the nucleation of cytoplasmic MT nucleation in a cell-cycle dependent manner, through a phosphorylation-dependent remodelling of the Mto1/2 complex.
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Hui, Wing-sze. "Spatial and temporal regulation of three collagen genes during sensory ray morphogenesis of caenorhabditis elegans /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202006%20HUI.
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Knight, Chad P. "Convex Model-Based Synthetic Aperture Radar Processing." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/2340.
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The use of radar often conjures up images of small blobs on a screen. But current synthetic aperture radar (SAR) systems are able to generate near-optical quality images with amazing benefits compared to optical sensors. These SAR sensors work in all weather conditions, day or night, and provide many advanced capabilities to detect and identify targets of interest. These amazing abilities have made SAR sensors a work-horse in remote sensing, and military applications. SAR sensors are ranging instruments that operate in a 3D environment, but unfortunately the results and interpretation of SAR images have traditionally been done in 2D. Three-dimensional SAR images could provide improved target detection and identification along with improved scene interpretability. As technology has increased, particularly regarding our ability to solve difficult optimization problems, the 3D SAR reconstruction problem has gathered more interest. This dissertation provides the SAR and mathematical background required to pose a SAR 3D reconstruction problem. The problem is posed in a way that allows prior knowledge about the target of interest to be integrated into the optimization problem when known. The developed model is demonstrated on simulated data initially in order to illustrate critical concepts in the development. Then once comprehension is achieved the processing is applied to actual SAR data. The 3D results are contrasted against the current gold- standard. The results are shown as 3D images demonstrating the improvement regarding scene interpretability that this approach provides.
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Bornheimer, Scott Joseph. "Spatial and temporal regulation of G-protein signaling elucidated by computational modeling and live cell FRET imaging." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3308008.
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Thesis (Ph. D.)--University of California, San Diego, 2008.Title from first page of PDF file (viewed June 12, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
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Dilruba, Shahana [Verfasser]. "Impact of ERK signaling and its spatial regulation on cisplatin sensitivity in ovarian cancer cells / Shahana Dilruba." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/1220912638/34.
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Zwickl, Klara, and Mathias Moser. "Informal environmental regulation of industrial air pollution: Does neighborhood inequality matter?" WU Vienna University of Economics and Business, 2014. http://epub.wu.ac.at/4420/1/EcolEcon_WorkingPaper_2015_1.pdf.
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This paper analyzes if neighborhood income inequality has an effect on informal regulation of environmental
quality, using census tract - level data on industrial air pollution exposure from EPA's Risk Screening Environmental
Indicators and income and demographic variables from the American Community Survey and EPA's Smart Location Database. Estimating a spatial lag model and controlling for formal regulation at the states level, we nd evidence that overall neighborhood inequality - as measured by the ratio between the fourth and the second income quintile or the neighborhood Gini coefficient - increases local air pollution exposure, whereas a concentration of top incomes reduces local exposure. The positive coefficient of the
general inequality measure is driven by urban neighborhoods, whereas the negative coefficient of top incomes is stronger in rural areas. We explain these findings by two contradicting effects of inequality: On the
one hand, overall inequality reduces collective action and thus the organizing capacities for environmental
improvements. On the other hand, a concentration of income at the top enhances the ability of rich residents
to negotiate with regulators or polluting plants in their vicinity.Series: Ecological Economic Papers
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Gidoin, Cynthia. "Relations entre structures de peuplement végétal et bioagresseurs de la culture principale dans les agroforêts tropicales. Application aux agroforêts à cacaoyers et à 3 bioagresseurs : la moniliose (Moniliophthora roreri) au Costa Rica, la pourriture brune (Phytophthora megakarya) et les mirides (Sahlbergellasingularis) au Cameroun." Thesis, Montpellier, SupAgro, 2013. http://www.theses.fr/2013NSAM0027/document.
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La valeur potentielle des agro-forêts tropicales comme modèle d'intensification écologique de l'agriculture est un sujet d'intérêt croissant. Les agro-forêts tropicales sont des agroécosystèmes caractérisés par une forte diversité végétale et une diversité d'organisation spatiale des individus. Les structures complexes de ces agroécosystèmes en font des systèmes « proches » des écosystèmes naturels. Cette complexité améliorerait la fourniture de nombreux services écosystémiques. Dans ce travail, nous nous sommes intéressés au service de régulation naturelle des bio-agresseurs des cultures. Notre hypothèse est que la complexité de structure (composition et structure spatiale) des agro-forêts influence la présence et l'intensité d'attaque des bio-agresseurs de la culture principale. En effet, l'augmentation de la diversité végétale à l'échelle de la parcelle diminuerait l'intensité d'attaque de bio-agresseurs spécialistes via la diminution de l'abondance de la ressource. Inversement, cette diversité amplifierait celle des bio-agresseurs généralistes via l'introduction potentielle d'hôtes alternatifs. Une diversité de structures spatiales d'individus associés est aussi susceptible d'influencer le microclimat et par son biais les bio-agresseurs des cultures. Pourtant, l'importance relative de l'effet de la composition (via la dilution ou l'amplification de la ressource) et de la structure spatiale (via l'altération du microclimat) du peuplement végétal sur l'intensité d'attaque de bio-agresseurs a rarement été étudiée. L'objectif de ce travail est de quantifier les interactions entre les caractéristiques de composition et de structure spatiale du peuplement végétal d'agroécosystèmes complexes et l'intensité d'attaque de bio-agresseurs de la culture principale à l'échelle de la parcelle. Ce travail est appliqué aux agro-forêts à cacaoyers du Costa Rica et du Cameroun. En effet, la culture du cacaoyer est l'une des rares encore réalisée traditionnellement au sein d'agro-forêts dans la majorité des pays producteurs. Nous nous intéresserons à trois bio-agresseurs du cacaoyer choisis pour leurs caractéristiques de dissémination et de développement contrastées : au Costa Rica, la moniliose sur un réseau de parcelles installées dans la région de Talamanca ; au Cameroun la pourriture brune et les mirides sur un réseau de parcelles installées dans la région Centre. Dans un premier temps nous avons construit des typologies descriptives des structures spatiales des agro-forêts à cacaoyers du Costa Rica et du Cameroun afin d'identifier la variabilité des structures spatiale des agro-forêts au sein d'une même région. Ces typologies ont permis d'identifier des structures spatiales horizontales variées allant de la régularité à l'agrégation significatives des arbres d'ombrage selon les pays étudiés. Dans un deuxième temps nous avons identifié et hiérarchisé les caractéristiques de composition et de structure spatiale à l'échelle de la parcelle agroforestière qui influencent l'intensité d'attaque de la moniliose au Costa Rica ; et de la pourriture brune et des mirides au Cameroun. La structure spatiale du peuplement végétal joue un rôle prépondérant dans l'ensemble de nos résultats. L'agrégation des arbres forestiers augmente l'intensité d'attaque de la moniliose au Costa Rica et la densité des mirides au Cameroun. La pourriture brune quant à elle augmente lorsque la densité des individus de la strate basse augmente à l'échelle de la parcelle. Pour finir, nous montrons que la quantité de tissus sensible plutôt que la composition en hôte explique l'intensité de la moniliose et la densité en miride. Ces résultats sont discutés en fonction des nombreux mécanismes qui relient la structure de la végétation aux bio-agresseurs et des caractéristiques de ces bio-agresseurs. Notre travail fournit une description précise de la structure d'agro-écosystèmes tropicaux complexesThe potential value of tropical agroforests as a model for ecological intensification of agriculture is a subject of increasing interest. Tropical agroforests are agroecosystems characterized by high plant diversity and a complex spatial structure of individuals. With their forest-like structures, agroforests are close to natural ecosystems. The complex structure of agroforests would seem to improve the provision of numerous ecosystem services.This work concerned natural pest and disease regulation services in complex agroecosystems. Our hypothesis was that complex agroforest structures (composition and spatial structure) influence the pest and disease attack intensity on the main crop. Indeed, an increase in plant diversity in agroecosystems is known to reduce specialized pest and disease attack intensity due to a decrease in resource abundance and density on a plot scale. Conversely, plant diversity could increase the generalist pest and disease attack intensity due to the potential introduction of alternative hosts. Moreover, diversity in plant spatial structure has an impact on microclimatic conditions and, thereby, on the pest and disease attack intensity. However, the relative importance of host composition effects on pest and disease intensity, due to resource dilution or amplification, and plant spatial structure effects, due to microclimatic alteration, is still unknown.Our objective was to quantify interactions between the composition and spatial structure characteristics of agroforests and the pest and disease attack intensity on a plot scale.This work was applied to cacao agroforests in Costa Rica and Cameroon. Indeed, cacao is one of the last crops still to be grown in traditional agroforests in the majority of producing countries. The study was conducted on two cacao diseases and one pest chosen for their contrasting spread and development characteristics: in Costa Rica, Frosty Pod Rot (FPR) intensity was studied in cacao agroforests in the Talamanca region; in Cameroon, Black Pod (BP) intensity and mirid density were studied in cacao agroforests in the Centre region.Firstly, we established shade tree spatial structure typologies for cacao agroforests in Costa Rica and Cameroon, in order to identify spatial structure diversity in the same region. A diversity of spatial structures was identified ranging from significant regularity to significant aggregation, depending on the shade tree stand and country studied.Secondly, we identified and classified the host composition, amount of sensitive tissue and the spatial structure characteristics of the associated plants, according to their explanatory power in explaining FPR intensity, BP intensity and mirid density in cacao agroforests. The spatial structure of the associated plants was a crucial characteristic of agroforests in explaining FPR and BP intensity and mirid density. Indeed, forest tree regularity decreased FPR intensity in Costa Rica and mirid density in Cameroon. The BP intensity was reduced by a decrease in the density of individuals belonging to strata lower than or equal to the cacao tree stratum. Lastly, the amount of sensitive tissue rather than the host composition variables explained the increase in FPR intensity in Costa Rica and the mirid density in Cameroon. Our results are discussed in line with several mechanisms that explain plant diversity and pest and disease relationships.Our work provides a precise description of complex tropical agroecosystem structures. We quantified the relationship between observed plant structures and the pest and disease regulation ecosystem service. In the context of agroecology, this work opens up prospects for identifying and understanding ecological mechanisms involved in natural pest and disease regulation in cacao agroforests on a plot scale
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Phillips, Jennifer Barber. "Spatio-temporal regulation of microtubule stability in the Caenorhabditis elegans zygote /." view abstract or download file of text, 2003. http://wwwlib.umi.com/cr/uoregon/fullcit?p3113023.
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Thesis (Ph. D.)--University of Oregon, 2003.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 75-80). Also available for download via the World Wide Web; free to University of Oregon users.
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Lim, Kean Fan. "State rescaling, experimental reforms and institutional continuity : the shifting spatial logics of socioeconomic regulation in post-1949 China." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50669.
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Drawing on the literature on state rescaling, this dissertation investigates how post-1978 layers of policy shifts interact with regulatory logics of Mao Zedong-era policies, and in turn how this reproduces what the Chinese state now deems to be ‘necessary’ forms of uneven development. It proceeds on the premise that the shifting regulatory geographies of the Chinese state constitute a prism through which to evaluate socioeconomic change in China. The analysis is presented in two parts. First, it questions the logics and implications of designating specific territories – Hengqin and Qianhai in the Pearl River Delta and Liangjiang in Chongqing – into “nationally strategic new areas” after the 2008 global financial crisis. These logics were assessed through triangulating three primary empirical sources: policy documents, published comments by state actors and interviews with planners and scholars in China. The contemporary cases are presented in two segments, each comprising two chapters (Chapters 6 to 9). The first chapter of each segment explores how the geo-historical context and key actors enabled the national designation, the second examines the implications of key policy experimentation in the areas. Working from these empirical findings, the dissertation revisited historical sources (memoirs from different state actors of the Mao era, statistics extending back to 1949, academic articles in China, etc.) and developed a geographical-historical narrative that evaluates how the spatial logics of socioeconomic regulation have evolved during and after the Mao era (Chapters 4 and 5). The outcome is a two-pronged, mutually-reinforcing attempt to theorize the past from the lens of the present, and to conceptualize the present through ascertaining the impacts of policies inherited from past regimes. In so doing, the dissertation problematizes simple ‘transition’ models that portray a unidirectional, epochal change in the post-1978 Chinese political economy, a change characterized by decentralized governance and intensified economic-geographical inequality. It emphasizes, instead, a more deeply sedimented pattern of development that is marked simultaneously by significant (and enduring) forms of uneven socioeconomic development and experimental (and capricious) attempts to transcend these forms.Arts, Faculty of
Geography, Department of
Graduate
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Maheshwari, Gargi 1972. "Biophysical regulation of cell motility by adhesion ligands and growth factors : effect of spatial presentation of the ligand." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9112.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1999.Includes bibliographical references.
A key problem in biomedical engineering today is in understanding the mechanisms which control cellular functions such as cell proliferation, migration and differentiation. The ability to engineer tissue replacements requires understanding of the interactions between the cell and its environment - the surface with which it interfaces and the fluid medium surrounding it. We are interested in designing a biologically inspired substrata which controls mammalian cell migration based on principles of receptor/ligand interactions involved in its regulation. Recent studies have shown that integrin cell surface receptors for the extracellular matrix (ECM) proteins initiate signaling cascades, some of which are in common with those initiated by growth factors. We have quantitatively investigated the potential synergy between growth factors and ECM ligands in governance of cell motility. In initial experiments using a model system of the ECM protein fibronectin and epidermal growth factor (EGF), we found that locomotion speed of a mouse fibroblast cell line is affected by combinations of EGF and fibronectin in diverse ways that can be accounted for by a biophysical model for migration. Following on these finding, we have designed a minimalistic artificial matrix using the linear peptide sequence, arginine-glycine-aspartic acid (ROD), derived from fibronectin as the adhesion ligand, conjugated to a protein resistant poly (ethylene oxide) (PEO) surface. With this system, we have identified a role for the micro-level spatial presentation of the ROD peptide integrin ligand in stimulating migration. In addition, we have investigated the role of presentation of EGF as a soluble ligand in its governance of cell motility. We find that presentation of EGF in an autocrine manner in human mammary epithelial cells, where the cell simultaneously synthesizes the receptor and the ligand, results in the regulation of the directionality of cell motion. Formation of cell surface EGF/EGFR complexes in an autocrine manner causes an increased persistence of cell motion which is abrogated upon addition of EGF into the bulk extracellular media. These studies highlight the importance of quantitative deconstruction of a biological problem and have important ramifications for the rational design of cell receptor/ligand interactions to control cell behavior.
by Gargi Maheshwari.
Ph.D.
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Fengler, Sven [Verfasser], Philippe [Akademischer Betreuer] Bastiaens, and Hernán E. [Gutachter] Grecco. "Spatial-temporal regulation of EGFR phosporylation by protein tyrosine phosphatases / Sven Fengler ; Gutachter: Hernán E. Grecco ; Betreuer: Philippe Bastiaens." Dortmund : Universitätsbibliothek Dortmund, 2017. http://d-nb.info/1136131981/34.
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Peoples, Brandon Kevin. "Applying ecological models to positive interactions among lotic fishes: implications for population and community regulation at multiple spatial scales." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/73340.
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Positive biotic interactions such as mutualism, commensalism and facilitation are ubiquitous in nature, but historically have received considerably less research attention than negative interactions such as competition, predation and parasitism. The paucity of research on positive interactions is particularly evident in stream ecosystems and in vertebrate communities. Stream fishes clearly provide an ideal system for advancing research on positive interactions. Many minnows (Cyprinidae) of eastern North America engage in a potentially mutualistic reproductive interaction known as nest association, in which individuals of one species (nest associates) spawn in nests constructed by host species. In nest association, hosts provide unsilted gravel substrate for spawning nest associates, and increased parental care to associate broods. High associate: host egg ratios can create a dilution effect, reducing the probability that host eggs will be preyed upon by egg predators. Nest associative interactions are common, but are relatively understudied compared to other interactions among stream fishes.
The goals of this study were to apply general ecological models to this novel system to (a) gain new insight into the mechanisms structuring nest associative stream fish communities, and (b) to use inference from stream fish communities to potentially expand and improve the general ecological models. These goals required completion of three objectives, including (1) examining the influence of abiotic and biotic contexts on reproductive behavior and fitness outcomes between a cyprinid host and associate, using the biological markets model to generate predictions; (2) examining the utility of the nest web framework (previously only used for cavity nesting vertebrate communities) and the stress gradient hypothesis (previously applied almost exclusively to plant communities) for predicting which associate species spawn on nests built by various nest building species, and the consequences of these choices, respectively; and (3) using two-species occupancy modeling to determine the relative influence of biotic interactions and habitat covariates on the co-occurrence of a host and two nest associates.
To accomplish these goals, I conducted a large-scale experiment to manipulate presence of mutualists (Nocomis leptocephalus, host; Chrosomus oreas, associate), egg predators (biotic context) and habitat quality (abiotic context). I conducted behavioral nest observations and conducted repeated stream fish stream fish community surveys to collect demographic data. I constructed a nest web from observational data, and implemented structural equation modeling through an information-theoretic framework to identify nest web plausibility across a large spatial extent. I tested some predictions of the stress gradient hypothesis by regressing juveniles-per-nest and a metric of cyprinid community structure on a composite measure of physical stress (scaled gradients of catchment-scale agricultural land use and catchment area). I used two-species occupancy modeling to model co-occurrence of N. leptocephalus hosts and two associates, C. oreas and Clinostomus funduloides, and used an information-theoretic framework to compare hypotheses representing the importance of biotic interactions, habitat covariates or both at determining species co-occurrence.
Results corroborated some (but not all) model predictions, and identified room for improvement in each of the general models. Nest associative spawning by C. oreas was not context dependent; C. oreas did not spawn in the absence of a reproductively active male N. leptocephalus at any treatment level. However, the net fitness outcome of host and associate species was mutualistic, and the interaction outcome switched from commensalistic to mutualistic with abiotic context. N. leptocephalus reproductive success was improved by C. oreas presence in less-silted habitats, but not in heavily-silted habitats. This is most likely because broods were subject to predation in both habitat types, but were also negatively affected by siltation in silted habitats. Accordingly, egg dilution by associates was not sufficient to support a mutualistic relationship in less favorable habitats. Results suggest that the biological markets model may be a useful tool for predicting fitness outcomes of nest associative mutualism, but may not be as useful for predicting the behavioral outcomes of obligate mutualisms. Future applications of the biological markets model should carefully consider species traits, specifically the degree to which trading behavior is obligate for participants. Future work with this model will yield more insight by considering highly facultative associates.
Nest webs constructed from nest observational data suggested an interaction topology in which strong (nearly-obligate) associates relied most frequently on N. leptocephalus nests, and less frequently on nests constructed by Campostoma anomalum. Weak (facultative) associates were seldom associated with nests constructed by either species, and probably spawned before hosts began nesting activity. Structural equation models corroborated this topology throughout the New River basin, although some less-supported model evidence specified some nest association by weak associates. Juveniles-per-nest of strong associates responded positively to physical stress, while this metric for other cyprinid reproductive groups showed no relationship. Proportional representation of Nocomis and strong associates also increased predictably with physical stress. This study suggests that the nest web framework can be informative to systems outside the ones for which it was developed; future studies may be able to use this framework to better understand the role of habitat-modifying species in communities other than cavity nesting terrestrial vertebrates and nest associative stream fishes. This work extended the nest web framework by (a) modeling the outcomes of interactions instead of the interactions themselves, and (b) by using structural equation modeling to test nest web predictions with an information-theoretic framework. This study also suggests that the stress gradient hypothesis can be useful for understanding interaction dynamics in vertebrate communities; this represents the first direct evidence that this model can be used in vertebrate communities. Further, I demonstrate that the stress gradient hypothesis may be extended to predict community structure. However, more research in a diversity of systems will be needed to determine the extent to which this can be applied.
This study provides some of the first evidence of large-scale positive co-occurrence patterns in vertebrates. However, the precise roles of habitat covariates and biotic interactions were species-specific. Occupancy results suggest that co-occurrence between N. leptocephalus and nest associate C. funduloides is driven only by reproductive behavioral interactions. Alternatively, evidence suggests that co-occurrence between N. leptocephalus and C. oreas is driven by both nest association and habitat covariates. That two-species occupancy modeling can be a useful tool for comparing difficult-to-test hypotheses involving biotic interactions at large spatial scales. This study represents the first quantitative, multi-scale treatment of positive interactions in stream ecosystems.
This study demonstrates that applying general ecological models to stream fish communities can yield new insights about both the study system and the models themselves. While models of negative interactions, food webs and dispersal have been applied to stream fishes, we stand to gain much ground by also considering positive biotic interactions. In doing so, stream fish ecologists will also be able to contribute to the advancement of general ecology, and thus raise awareness for these understudied ecosystems and taxa.Ph. D.
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Heinelt, Kaatje Friederike [Verfasser], Philippe [Akademischer Betreuer] Bastiaens, and Leif [Gutachter] Dehmelt. "Systems analysis of the spatial regulation of oncogenic Ras signalling / Kaatje Friederike Heinelt ; Gutachter: Leif Dehmelt ; Betreuer: Philippe Bastiaens." Dortmund : Universitätsbibliothek Dortmund, 2017. http://d-nb.info/1136471596/34.
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Lucas, Tanguy. "Spatio-temporal regulation of hunchback during the zygotic genome activation in Drosophila." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066707.
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Les gradients morphogénétiques contrôlent l'émergence de polarités axiales au cours du développement. Bien que la dynamique d'établissement de ces gradients soit bien comprise, la précision des mécanismes d'activation agissant en aval restent à élucider. Nous abordons cette question avec le gradient de Bicoid qui fournit rapidement une réponse transcriptionnelle robuste dans l'embryon de drosophile. Cette robustesse survient malgré le challenge imposé par de fréquentes mitoses dépourvues de transcription. Un calcul théorique intégrant les paramètres physiques de Bicoid (concentration, diffusion) indique que la mesure précise de concentration de Bicoid ne peut être effectuée à chaque interphase en 5-6mn. Il a donc été proposé que l'acquisition rapide de cette robustesse repose sur une mémorisation de l'état transcriptionnel au cours des divisions. Pour tester cette hypothèse, j'ai adapté à l'embryon de drosophile le système MS2 d'étiquetage des ARN dans les cellules vivantes et démontré qu'il permettait de suivre la dynamique transcriptionnelle dans un organisme pluricellulaire vivant. De manière inattendue, le rapporteur MS2 s'exprime aussi postérieurement ce qui m'a empêché de tester l'hypothèse de mémorisation. J'ai montré que cette expression postérieure est due à la présence de sites de fixation pour le facteur de transcription Zelda dans la cassette MS2. Un nouveau rapporteur MS2, dépourvu de ces sites récapitule l'expression endogène et fournit un outil de choix pour tester l'hypothèse de mémorisation. Ce travail ouvre de nouvelles perspectives pour comprendre la dynamique transcriptionnelle sur laquelle repose l'émergence des patrons d'expression développementauxMorphogen gradients provide concentration-dependent positional information along polarity axes. Although the dynamics of these gradients is well described, precision and noise in the activation processes acting downstream remain unclear. To address this question, we study the response to the Bicoid gradient that elicits very rapidly a robust transcriptional response in young fly embryos. This robustness occurs despite the challenge imposed by frequent mitoses during which transcription is interrupted suggesting that nuclei measure the Bicoid concentration during the 5-6 mn interphases. Modeling using statistical mechanics and Bicoid physical parameters do not account for accurate measurement of Bicoid concentration in such a short period. It was proposed that rapid robustness of the Bicoid response relies on a memorization process allowing nuclei to recall Bicoid concentration from previous cycles. To understand how the Bicoid system resists to the challenge imposed by mitosis, I have adapted the MS2 RNA-tagging approach to fly embryos and shown that it can be used to quantify transcription dynamics in a living multicellular organism. Unexpectedly, the MS2 reporter was also expressed in the posterior of the embryo making it impossible to directly test the memorization hypothesis. I have shown that this posterior expression is due to binding sites for the transcription factor Zelda unexpectedly localized in the MS2 cassette. A newly engineered MS2 reporter removing those sites faithfully reproduces the endogenous expression providing a powerful tool to test the memory hypothesis. This work opens new avenue to decipher the transcription dynamics underlying pattern formation