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Zhang, Renshan, and 张仁善. "Functional analysis of two arabidopsis purple acid phosphatases : AtPAP2 and AtPAP9." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2015. http://hdl.handle.net/10722/211114.
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Law, Yee-song, and 劉益松. "Biological roles of atpap2 in the mitochondria." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2015. http://hdl.handle.net/10722/211155.
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Zhang, Youjun, and 张有君. "Growth promoting effects of AtPAP2 in potato and camelina." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46476945.
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Silverstein, Robert S. "Regulation of the Atp2b2 gene /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/10656.
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Douville, Élise. "Structure, assemblage et comportement hydrodynamique d'AtPP2-A1 et AtPP2-A2 chez Arabidopsis thaliana." Nantes, 2010. http://www.theses.fr/2010NANT2093.
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Chez les Dicotylédones, les tubes criblés contiennent du saccharose transporté à longue distance par flux de masse et des inclusions protéiques, appelées protéines P. Chez A. Thaliana, les protéines P se trouvent sous forme de filaments et des études d’immunolocalisation ont confirmé que les PP2s sont associées aux protéines P. Deux gènes PP2 sont exprimés spécifiquement dans le phloème: AtPP2-A1 et AtPP2-A2. A partir d’observations microscopiques, il a été émis l’hypothèse que les protéines P pourraient, en réponse à des blessures du phloème, participer à l'occlusion des tubes criblés par des mécanismes d’assemblage particuliers. Afin de vérifier cette hypothèse, les protéines recombinantes PP2-A1 et PP2-A2 ont été produites dans E. Coli et leurs structure et autoassemblage ont été étudiés dans différentes conditions physico-chimiques, proche des conditions de la sève élaborée. Les protéines PP2-A1 et PP2-A2 sont présentes en solution sous forme d'oligomères allongés quel que soit le pH, avec un degré d'oligomérisation N plus élevé pour PP2-A2 que pour PP2-A1. Ces résultats obtenus par diffusion des rayons X aux petits angles et les observations réalisées en microscopie électronique, suggèrent que les oligomères s'auto-associent pour former des structures torsadées filamenteuses. L’augmentation de la force ionique amplifie l’auto-association de PP2-A1 et A2. En revanche, la présence de calcium, de saccharose ou la vitesse de cisaillement n’affecte pas l’auto-association de PP2-A1. L’ensemble de ces résultats suggèrent que la présence de PP2 n’altère pas le flux de sève élaborée dans les tubes criblésDicotyledonous sieve elements typically contain saccharose transported at long distances by mass flow and protein inclusions, called P-Proteins. In Arabidopsis thaliana, P-proteins are found as filaments and immunolocalization studies had confirmed that PP2s are indeed associated to Pproteins. Two PP2 genes were shown to be expressed specifically in the phloem: AtPP2-A1 and AtPP2-A2. Based on observations in microscopy, it was hypothesized that P proteins could, in response to injury of the phloem, participate in the occlusion of sieve tubes by peculiar assembly mechanisms. In order to check this hypothesis, PP2-A1 and PP2-A2 recombinant proteins were produced in E. Coli and their structure and self-assembly properties were studied under different physical chemical conditions, close to phloem sap conditions. Proteins PP2-A1 and PP2-A2 were present in solution as elongated shape oligomers whatever the pH, with a degree of oligomerization N being higher for PP2-A2 than for PP2-A1. These results obtained by small angle X-ray scattering together with observations using transmission electron microscopy suggest that the oligomers self-associate to form an arrangement of filamentous and twisted structures. Increasing ionic strength enhances the proteins self-association. By the contrary, the presence of calcium, sucrose or shear rate do not affect PP2-A1 self-association. Alltogether, these results suggest that the presence of PP2 proteins within phloem sieve tubes do not compromise mass flow
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Tietz, Olaf. "Funktionelle Charakterisierung des AtPIN1-Proteins aus Arabidopsis thaliana." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=969066104.
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Hütter, Michael. "Rolle von CACNA1A, ATP1A2 und SCN1A für die sporadische hemiplegische Migräne." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-101418.
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Nuntasoontorn, Komsun. "Functional analysis of the Arabidopsis thaliana meiotic proteins AtPCH2 and AtCHR24." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4921/.
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In the past decade Arabidopsis thaliana has become an important system for studying meiosis in flowering plants. The identification of meiotic mutants has provided an important approach to studying plant meiosis. The availability of the Arabidopsis genome sequence together with developments in proteomics and bioinformatics provides an additional route for the identification of meiotic proteins and analysis of their functional interrelationships. This study has used a proteomics approach to identify a member of the SWI2/SNF2 chromatin remodelling gene family (Atchr24). Although a variety defects was observed in Atchr24 male meiocytes cytogenetic, at least two T-DNA insertion lines on this gene appear normal. Secondly, this research has also used a bioinformatics approach to identify a potential orthologue of Pch2/TRIP13 in Arabidopsis. PCH2 (Pachytene checkpoint 2) is a member of the AAA+ ATPase family of proteins. This study reveals that AtPCH2 plays an essential role in the controlled formation of meiotic crossovers (COs). Cytogenetic analysis of two Atpch2 T-DNA insertion lines revealed a high frequency of univalents at MI. The number of chiasmata (COs) is reduced to ~ 70% of wild-type (WT). Genetic analysis revealed that Atpch2 has significantly weaker CO interference than WT leading to a redistribution of COs along the chromosomes. The recombination defect is accompanied by incomplete chromosome synapsis. Immunolocalisation of the chromosome axis protein AtASY3 and cohesin, AtSYN1 appears normal. However in contrast to WT, AtASY1 co-localises with the synaptonemal protein AtZYP1 in ii Atpch2 rather than becoming depleted in regions of synapsis and the meiotic progression of Atpch2 is delayed during pachytene by ~5 hours. These observations suggest a defect in remodeling of the chromosome axes and highlight how this process is essential for normal CO control.
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Stavridou, Ioanna Stavros. "Novel binding partners of an Arabidopsis phosphatidylinositol phosphate 5-kinase, AtPIPKβ." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615136.
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Attílio, Lísia Borges. "Transformação genética de laranja doce (Citrus sinensis L. Osbeck) com o gene D4E1 dirigido pelos promotores CaMV35S ou AtPP2." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-23042013-162934/.
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O Brasil é o maior produtor de laranja doce do mundo. O histórico da citricultura brasileira é marcado por uma sucessão de doenças causadas por diferentes agentes etiológicos. Entre as principais doenças que afetam a cultura, têm levado a maiores prejuízos, as bacterianas, com destaque para o cancro cítrico causado por Xanthomonas citri subsp. citri e o Huanglongbing associado a três espécies de \"Candidatus Liberibacter\". Devido à ausência de cultivares de laranja doce resistentes a estas doenças, a transformação genética é uma alternativa promissora para obtenção de plantas resistentes. Uma das estratégias no uso da transgenia para conferir ação contra bactérias é a inserção de genes que codificam peptídeos antimicrobianos como o D4E1, um peptídeo sintético, que tem apresentado eficiência no controle de doenças fúngicas e bacterianas de várias culturas, in vivo e in vitro. Este trabalho foi realizado com o objetivo de obter plantas transgênicas de laranja doce das cultivares \'Hamlin\', \'Pêra\' e \'Valência\', via Agrobacterium tumefaciens, expressando o gene D4E1, dirigido pelos promotores CaMV35S (Cauliflower mosaic virus 35S promoter) de expressão constitutiva ou pelo AtPP2 (Arabidopsis thaliana phloem protein 2) com expressão preferencial no floema, visando obter plantas resistentes a doenças bacterianas. Foram obtidas 13 plantas transgênicas da cultivar \'Hamlin\', 10 da cultivar \'Pêra\' e 8 da cultivar \'Valência\', contendo a construção gênica CaMV35S/D4E1 e 19 plantas transgênicas da cultivar \'Hamlin\', 6 da cultivar \'Pêra\' e 15 da cultivar \'Valência\' contendo a construção gênica AtPP2/D4E1. As plantas transgênicas apresentaram um a três eventos de inserção do T-DNA no genoma. Os níveis de expressão do transgene dirigido pelo promotor de expressão preferencial no floema foi menor comparado ao das plantas contendo o transgene dirigido pelo promotor de expressão constitutiva. Os resultados da expressão do transgene permitem selecionar plantas com maior expressão de cada uma das construções gênicas, para que, futuramente, estas sejam multiplicadas e avaliadas quanto à resistência ao cancro cítrico e ao HLB.Brazil is the largest sweet orange producer in the world. The history of the Brazilian citrus industry is marked by a series of diseases caused by different etiologic agents. Among the diseases affecting the culture, those caused by bacteria are the ones that have caused more significant losses, especially the citrus canker caused by Xanthomonas citri subsp. citri, and huanglongbing (HLB) associated with three \"Candidatus Liberibacter\" bacteria species. Due to the absence of genetic resistance to these diseases in commercial sweet orange cultivars, the genetic transformation is a promising alternative to produce resistant plants. One of the strategies to produce transgenic resistant plants to bacteria is the use of genes that code for antimicrobial peptides, such as D4E1, a antimicrobial synthetic peptide, which has shown efficient results controlling diseases caused by bacteria and fungi in several crops, through in vitro and in vivo experiments. The aim of this study was to produce \'Hamlin\', \'Pêra\' and \'Valencia\' sweet orange transgenic plants, via Agrobacterium tumefaciens, expressing the D4E1 gene driven by the constitutive promoter Cauliflower mosaic virus (CaMV35S) or Arabidopsis thaliana phloem protein 2 (AtPP2), a promoter preferentially expressed in the phloem. It was possible to regenerate 13 \'Hamlin\' transgenic lines, 10 \'Pêra\' transgenic lines and 8 \'Valencia\' transgenic lines bearing the gene construct CaMV35S/D4E1, whereas 19 \'Hamlin\' transgenic lines, 6 \'Pêra\' transgenic lines and 15 \'Valencia\' transgenic lines bearing the AtPP2/D4E1 gene construct were regenerated. The transgenic plants had one to three T-DNA insertion events in the genome. The transgene expression levels in transgenic plants for D4E1 gene driven by the phloem preferential promoter were lower than the transgenic expression levels of the transgene driven by the constitutive promoter. Transgene expression levels results may allow the selection of those plants with higher expression levels of each genetic construct for future multiplication and evaluation for citrus canker and HLB resistance.
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Pierrugues, Olivier (19. "Caractérisation moléculaire de deux gènes AtPap2, codant des lipides phosphate phosphatases chez Arabidopsis : implication potentielle d'AtPap2a dans la signalisation du stress." Aix-Marseille 1, 2000. http://www.theses.fr/2000AIX11021.
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Le stress engendre par l'irradiation active les voies de transduction du signal necessaires a l'arret du cycle cellulaire et a la reparation des lesions sur l'adn, ou alternativement, la mort cellulaire programmee. Nous avons caracterise le gene atpap2a dont la transcription est induite de facon transitoire et rapide apres irradiation d'arabidopsis thaliana. Atpap2a code pour une proteine presentant de fortes homologies avec une famille de proteines membranaires caracterisees chez les mammiferes et la levure : les lpp, qui interviennent dans la transduction du signal. Le sequencage systematique du genome d'arabidopsis a permis de mettre en evidence deux genes codant pour des proteines apparentees a atpap2a : atpap2b et atpap2c (que nous n'avons pas etudie). Les genes de plante atpap2a et atpap2b, exprimes chez la levure, restaurent effectivement les activites acide phosphatidique phosphatase et diacylglycerolpyrophosphate phosphatase du double mutant de levure dpp1lpp1. Atpap2a et atpap2b presentent, des proprietes enzymatiques differentes. L'expression des genes atpap2a et atpap2b, n'est pas regulee de la meme facon apres differents types de stress biotiques et abiotiques. L'expression d'atpap2a est induite apres le stress, alors que celle d'atpap2b ne l'est pas. Atpap2a est exprime essentiellement dans les feuilles d'arabidopsis, alors qu'atpap2b est exprime dans tous les organes vegetaux. Les fonctions de ces genes homologues structuraux pourraient donc etre differentes. Atpap2a interviendrait dans la reponse generale du vegetal au stress et atpap2b dans le metabolisme phospholipidique.
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La, Camera Sylvain. "Caractérisation fonctionnelle de lipide acyl-hydrolases (LAH) : Etude de l'implication de AtPLP2 dans la résistance aux agents pathogènes chez Arabidopsis thaliana." Université Louis Pasteur (Strasbourg) (1971-2008), 2005. http://www.theses.fr/2005STR13058.
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La libération d’acides gras à partir de lipides membranaires est régulée en réponse à différents stress. Elle est catalysée par des enzymes appelées lipide acyl-hydrolases (LAH) dont le rôle supposé est d’être impliquées dans la résistance antimicrobienne et de fournir des précurseurs de dérivés d’acides gras, les oxylipines. L’exploration du génome de la plante Arabidopsis thaliana nous a permis de mettre en évidence plusieurs groupes structuraux de gènes codant pour des LAH putatives et de montrer que plusieurs membres sont induits en réponse à différents microbes. Nous avons donné la priorité à l’étude fonctionnelle des patatines. Cette famille comprend 9 gènes, dont deux (AtPLP2 et AtPLP7) sont induits dans les feuilles infectées. L’accumulation de AtPLP2 en réponse à Botrytis cinerea et Pseudomonas syringae est dépendante des signaux de défense, éthylène et acide jasmonique. L’expression d’une fusion AtPLP2-GFP et l’analyse des propriétés biochimiques indiquent que cette protéine est une LAH cytoplasmique. Des plantes transgéniques modifiées dans l’expression de AtPLP2 ont été testées pour leurs niveaux de résistance. De façon inattendue, AtPLP2 favorise la progression du champignon Botrytis et la susceptibilité vis-à-vis de bactéries avirulentes, alors que les plantes réprimées sont plus résistantes. Ces données indiquent que l’activité lipolytique dépendante de AtPLP2 est recrutée par certains pathogènes pour faciliter la colonisation de la plante hôte. AtPLP2 semble également potentialiser la mort cellulaire lors de l’infection par B. Cinerea et réduire la capacité de la réaction d’hypersensibilité à restreindre la multiplication de bactéries avirulentes. L’étude systématique des LAH chez Arabidopsis a permis d’identifier des candidats prometteurs pour une analyse fonctionnelle détaillée. Les outils générés, dont les mutants knock-out, seront au centre des études futures des phénomènes de mobilisation d’acides gras dans les mécanismes de défense des plantesMembrane lipid catabolism is regulated in response to several stresses. Enzymes responsible for lipid hydrolysis are named lipid acyl hydrolases (LAH). An important role anticipated for such enzymes is to be involved in antimicrobial resistance and to provide precursors for the biosynthesis of oxylipins that are regulatory fatty acid derivatives. Exploration of the Arabidopsis thaliana genome has revealed the existence of numerous structural families of potential LAH genes, with members being upregulated in response to biotic stress. We have given priority to the functional study of Arabidopsis LAH related to patatin. This family comprises 9 members, two of which (AtPLP2 and AtPLP7) being strongly upregulated in leaves challenged with pathogens. AtPLP2 protein accumulation in response to the fungus Botrytis cinerea or Pseudomonas syringae bacteria is dependent on jasmonic acid and ethylene signaling. Expression of a AtPLP2-GFP fusion and biochemical analysis of recombinant AtPLP2 indicates that AtPLP2 encodes a cytoplasmic LAH. Transgenic plants with altered levels of AtPLP2 protein were generated and assayed for pathogen resistance. Unexpectedly, AtPLP2 expression increases B. Cinerea colonization and susceptibility to avirulent bacteria whereas silenced plants displayed enhanced resistance. Collectively, the data indicate that AtPLP2-encoded lipolytic activity is recruited by pathogens with different lifestyles to facilitate host colonization. Particularly, AtPLP2 potentiates plant cell death upon infection by B. Cinerea and reduces the efficiency of the hypersensitive response known to normally restrict avirulent bacteria multiplication. This global Arabidopsis LAH study opened some perspectives in identifying several candidates genes for detailed functional studies. Tools like numerous LAH knock-out mutants obtained will be the basis of our future work to decipher fatty acid mobilisation processes during plant defense responses
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Rousselle, Anthony. "Role of the (Pro)renin Receptor [(P)RR/ATP6ap2] in Osteoclast and Macrophage Physiology." Doctoral thesis, Humboldt-Universität zu Berlin, 2017. http://dx.doi.org/10.18452/18599.
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Vor zehn Jahren wurde der (Pro)Renin-Rezeptor [(P)RR] entdeckt und als neuer Bestandteil des Renin-Angiotensin-Systems beschrieben. Neuere Studien ergaben, dass der (P)RR mit der vakuolären H+-ATPase (V-ATPase) assoziiert sein kann, weshalb er auch V-ATPase associated protein 2 (ATP6ap2) genannt wird.
In Osteoklasten befinden sich V-ATPase hauptsächlich an der zur Knochenoberfläche gerichteten Plasmamembran und transportieren Protonen in den extrazellulären Raum. Mäuse mit genetischer Deletion verschiedener V-ATPase-Untereinheiten charakterisiert durch einen Anstieg von Knochenmasse (Osteopetrose). In der vorliegenden Arbeit fanden wir heraus, dass (P)RR stark in reifen Osteoklasten in vitro und in vivo exprimiert wird. Mäuse mit genetischer Deletion des (P)RR in Osteoklasten wurden durch einen komplexen Knochen-Phänotyp mit reduzierter Knochendichte charakterisiert. (P)RR-defiziten Osteoklasten wiesen vermehrte Differenzierung und/oder Aktivität in vitro und in vivo auf. Wir postulieren deshalb, dass der (P)RR die in der Plasmamembran lokalisierten V-ATPase nicht direkt reguliert, sondern mit der physiologischen Aktivität der Osteoklasten durch andere Mechanismen interferiert.
Macrophagen sind speziell auf die Immunabwehr ausgerichtete Fresszellen (Phagozyten). Phagozytose ist ein wesentlicher Zellprozess der die V-ATPase in Lysosomen braucht um die eingeschlossenen Pathogen zu zerstören. Wir generierten transgene Ratten mit konditionellen knockdown von (P)RR unter Nutzung eines Doxyzyclin-induzierten shRNA-Expressionssystems. Eine effiziente (P)RR-Depletion in Makrophagen wurde durch Behandlung mit Doxyzyclin in vivo im Trinkwasser und in vitro im Kulturmedium erreicht. Die vorliegende Arbeit zeigt, dass die Verschiebung des vesikulären pHs erst ziemlich spät nach (P)RR-Depletion auftritt. Wir fanden heraus, dass (P)RR-Depletion weder Phagozytose noch Endozytose beeinträchtigte, sondern für das Recycling des Transferrin-Rezeptors zur Plasmamembran wichtig ist.A decade ago, the (pro)renin receptor [(P)RR] was discovered and depicted as a new component of the renin-angiotensin system. However, recent studies have put in evidence that the (P)RR associate with and regulate the vacuolar H+-ATPase (V-ATPase), hence its other name vacuolar H+-ATPase associated protein 2 (ATP6ap2). In osteoclasts, V-ATPases are mainly located at the plasma membrane facing the bone surface and extrude protons into the extracellular space. Mice with genetic deletion of various V-ATPase subunits are characterized by an increase of bone mass (osteopetrosis). In this work, we found that the (P)RR is highly expressed in mature osteoclasts in vitro and in vivo. Mice with genetic deletion of the (P)RR in osteoclasts developed a complex bone phenotype characterized by a reduced bone density. Osteoclasts lacking (P)RR displayed increased differentiation and/or activity in vitro and in vivo. We therefore suggest that the (P)RR does not directly regulate V-ATPases located at the plasma membrane but rather interferes with osteoclast physiology through other mechanisms. Macrophages are professionalized phagocytes crucial for immune response. Phagocytosis is an essential cellular process, which requires lysosomal V-ATPases for degradation of engulfed pathogens. We generated transgenic rats with a conditional depletion of the (P)RR with the use of a doxycycline-induced shRNA expression system. Efficient (P)RR depletion in macrophages was accomplished by doxycycline treatment in vivo in drinking water and in vitro in culture medium. In this work, we found that the impairment of vesicular pH occurs lately after (P)RR deletion. Also, we found that (P)RR deletion did not impair neither phagocytosis nor endocytosis but rather perturbed the recycling of the transferrin receptor to the plasma membrane.
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Ceciliato, Paulo Henrique de Oliveira. "Dissociabilidade das funções de inibição da expansão celular e de alcalinização do peptídeo AtRALF1 e identificação dos aminoácidos determinantes da atividade de alcalinização." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11137/tde-23062015-155306/.
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RALFs são peptídeos hormonais de aproximadamente 5kD que regulam negativamente o alongamento celular. Dentre suas atividades biológicas, a alcalinização do meio extracelular e a inibição do alongamento celular são tidas como associadas, pois a acidificação do meio extracelular é necessária para a expansão celular. A atividade de alcalinização e a de inibição do crescimento são medidas em dois ensaios distintos: o ensaio de alcalinização do meio extracelular de células em suspensão e o ensaio do crescimento de raiz primária de plantas jovens. Buscando-se fazer ambas as avaliações da inibição da expansão celular e da alcalinização em um único modelo de estudo, tomou-se como medida da expansão celular o volume das células decantadas (VCD). Quando o tampão MES ou o pré-tratamento com \"Fusicoccin\" foi utilizado para se atenuar o efeito de alcalinização do AtRALF1, verificou-se que o efeito de inibição do alongamento celular não sofreu alteração. Em arabidopsis são encontrados nove peptídeos RALF, que apresentam alta similaridade com o RALF original de tabaco. Com exceção do AtRALF4, todos são capazes de alcalinizar o meio extracelular e inibir raízes. A comparação da estrutura primária do AtRALF4 com os demais RALFs mostra que poucos resíduos são distintos entre eles, sugerindo que estes possam ser os determinantes das atividades de inibição e alcalinização. A alteração de um destes resíduos, AtRALF4(N92A), é capaz de restaurar a capacidade do AtRALF4 de inibir as raízes sem, no entanto, recuperar a atividade de alcalinização. Quando três outros resíduos exclusivos do AtRALF4 foram substituídos pelos seus correspondentes do AtRALF1, observa-se uma restauração parcial da alcalinização, desta vez, sem alterar a capacidade de inibir as raízes. Recentemente, foi mostrado pelo nosso grupo que o peptídeo AtRALF1 induz a expressão de genes relacionados ao rearranjo da parede celular. Quando verificado por PCR quantitativa, contatou-se que somente os peptídeos mutantes que apresentam atividade de inibição do crescimento são capazes de promover uma indução semelhante. Ainda, utilizando gel indicador de pH, verificou-se que plantas transgênicas super-expressando AtRALF1 (35S:AtRALF1) acidificam o meio durante seu crescimento de maneira semelhante a plantas selvagens. O peptídeo de defesa AtPEP1, a exemplo dos peptídeos RALF, também promove a alcalinização do meio extracelular. A utilização de drogas para reproduzir ou atenuar o efeito de alcalinização promovido por este peptídeo sugere que a expressão dos genes responsivos a AtPEP1 também não está relacionada à alteração na atividade das próton-ATPases. Finalmente, quando mutantes para ambos os receptores de AtPEPs foram utilizados (atpepr1/r2) em gel indicador de pH, verificou-se que estes alcalinizam o pH da rizosfera na presença do peptídeo. Nossos dados somados sugerem uma dissociação das atividades biológicas de alcalinização do meio extracelular e de inibição da expansão celular. A alteração na atividade das próton-ATPases pode não ser apenas uma mensagem secundária do efeito biológico, mas sim outra fonte de informação independente e ainda pouco explorada como tal.RALFs are 5kD peptide hormones that negatively regulates cell expansion. Among the biological activities of the RALF peptide, the extracellular alkalinization and cellular expansion inhibition were previously suggested to be associated, once the extracellular acidification is required to cell expansion. Usually, the alkalinization and cell expansion inhibition activities are evaluated in two different assays, the cell suspension medium alkalinization and the plantlet root growth inhibition. We manage to set an assay in which both cell expansion inhibition and extracellular alkalinization activities could be evaluated. Using the package suspension cell volume through decantation as a value of cell expansion, we evaluated the relation between alkalinization and cell expansion inhibition in different conditions. When the MES buffer or the pre-treatment with Fusicoccin was used to arrest the AtRALF1 extracellular alkalinization, the package cell volume inhibition activity was not affected. There are 9 RALF peptides encoded in arabidopsis plants that are closely related with the first isoform isolated from tobacco. With exception of the AtRALF4, all those isoforms are able to alkalinize the extracellular medium and arrest root growth. Comparing the AtRALF4 with other eight isoforms, we verified that are few different amino acids between them, suggesting that those amino acids could be essential for the biological activities. The rescue of one of those amino acids, AtRALF4(N92A), was able to regain the root growth inhibition activity of the AtRALF4 peptide, although the extracellular alkalinization activity was not restored. When three other AtRALF4 amino acids were substituted by their AtRALF1 correspondent, there is a partial rescue of the extracellular alkalinization activity, but no alterations in the root growth inhibition. We had recently shown that the AtRALF1 peptide induces the expression of genes related to cell wall rearrangement. The quantitative PCR analyses demonstrates that only the mutant peptides that are able to arrest root growth are also able to induce the gene expression. When submitted to a pH indicator, it was verified that AtRALF1 overexpressing plants acidifies it during its growth, as much as wild type plants.The defense peptide AtPEP1, similarly of AtRALF1, also triggers extracellular alkalinization. The use of proton-pump chemical modulators to simulate or arrests AtPEP1 extracellular alkalinization activity suggests that the gene expression of the AtPEP1-responsive genes is not related to changes in plasma membrane proton pump activity. Finally, when double mutants for both the AtPEP1 receptors (atpepr1/r2) were submitted to a pH gel indicator, it was seen that they alkalinize the rhizosphere pH in the presence of the AtPEP1 peptide. Our data suggests that the extracellular alkalinization and arrest of cell expansion activities are dissociated. The proton pump modulation activity may not be only a secondary messenger, but another source of information independent and yet to be explored.
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Friml, Jirí. "Isolation and characterization of novel AtPIN genes from Arabidopsis thaliana L." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961738510.
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Gosch, Jonas [Verfasser]. "Epigenetische Suppression von RASAL1 und ATP2A2 als Biomarker und Therapieansatz bei kardialer Fibrogenese / Jonas Gosch." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1214440169/34.
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Ottenschläger, Iris. "Gravity regulated differential auxin transport in Arabidopsis roots and the search for interaction partners of AtPIN1." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964941848.
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Lefebvre, Valerie. "Identification of Novel Parkinson’s Disease Genes Involved in Parkin Mediated Mitophagy." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30222.
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Mitochondrial dysfunction has been implicated as one of the primary causes of Parkinson's disease (PD). The proteins PINK1, a serine-threonine kinase, and Parkin, an E3 ubiquitin ligase, are mutated in many genetic cases of PD. In healthy individuals, Parkin is recruited to damaged mitochondria and leads to autophagic degradation of mitochondria in a process termed mitophagy. Following depolarization of the mitochondrial membrane, PINK1 is stabilized on the outer mitochondrial membrane, and triggers Parkin translocation from the cytosol to mitochondria. Precisely how this phenomenon is regulated is still unclear. We employed RNA interference (RNAi) technology in a 384-well format to identify novel genes that are required for Parkin recruitment to mitochondria. We identified ATPase inhibitory factor 1 (IF1) as the strongest hit required for Parkin recruitment following treatment with the protonophore CCCP. We show that IF1 is upstream of PINK1 and Parkin, and required to sense mitochondrial damage by allowing the loss of membrane potential. In cells treated with CCCP, the absence of IF1 permits the ATP synthase to run freely in reverse, consuming ATP to maintain potential across the inner mitochondrial membrane, thus blocking PINK1 and Parkin activation. Interestingly, Rho0 cells, that lack mitochondrial DNA, have downregulated endogenous expression of IF1 in order to maintain mitochondrial function. Overexpression of IF1 in Rho0 cells results in the depletion of mitochondrial membrane potential and the initiation of mitophagy. These data demonstrate a unique role for IF1 in the regulation of mitochondrial quality control that has not been explored in the etiology of PD.
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Ariyaratne, Menaka M. "A new perspective on polyamine biosynthesis and transport in arabidopsis thaliana." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1555693507751475.
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Coleman, Jonathan Allan. "P4-ATPase structure-function relationships : mechanism and roles of ATP8A2-CDC50A in aminophospholipid transport, protein trafficking, and visual disorders." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44073.
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P₄-ATPases are a family of membrane transporters which have been implicated in the energy-dependent transport of aminophospholipids from the exocytoplasmic to cytoplasmic surface of biological membranes. This thesis investigation examined the structure-function relationships of ATP8A2, a novel member of the P₄-ATPase family initially discovered in a proteomic study of photoreceptor outer segments. Photoreceptor outer segments are organelles which consist of stacks of membraneous discs containing visual pigment
molecules. ATP8A2 is shown to be present in photoreceptor outer segment discs and
preferentially transports phosphatidylserine towards the cytosolic leaflet, providing the first
direct demonstration of lipid transport by a purified mammalian P₄-ATPase. CDC50A, the β-subunit of ATP8A2 was discovered using mass spectrometry and Western blotting. Subunit interactions are mediated through the extracellular and membrane domains of CDC50A. The N-terminal domain of CDC50A appears to play a role in pump modulation. ATP8A2 forms a phosphoenzyme intermediate at Asp⁴¹⁶ and phosphatidylserine
appears to be transported in a similar manner to that of other cation-transporting P-type
ATPases. The phosphoenzyme exists in two distinct conformations: E₁P and E₂P. The E₂P form interacts with aminophospholipids. Lys⁸⁷³ in transmembrane segment M5 located in a region known to be important for cation binding for P-type ATPases is critical for phosphatidylserine binding. Glu¹⁹⁸ in the DGET motif is essential for E₂P dephosphorylation. ATP8A2 gene expression was disrupted in mice using a neo cassette. Knockout mice develop short outer segments and visual function is impaired. Modification of transbilayer
asymmetry and composition appear to be responsible for reduced visual function rather than structural defects. The decrease in outer segment length suggests that ATP8A2 is involved in vesicular trafficking of proteins to the outer segment by regulating the step of vesicle budding possibly from the trans-Golgi network. We speculate that ATP8A2 plays a similar role in other neuronal cells and thus provide insight into the phenotype of human disorders caused by mutations in ATP8A2.
In summary, this study has identified for the first time the transported substrate of a mammalian P₄-ATPase, discovered protein-protein interactions regulating function, elucidated the mechanism of lipid transport, and illuminated the function of ATP8A2 in photoreceptor and neuronal biology.
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Burckle, Céline. "Le Récepteur de la prorénine/rénine-RR/ATP6AP2 : données de biologie cellulaire : poids moléculaire, topologie, localisation subcellulaire : approche fonctionnelle." Paris 7, 2006. http://www.theses.fr/2006PA077227.
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In vivo, la fonction du récepteur de la rénine (RR/ATP6AP2) n'est pas connue. Des résultats divergents concernant sa localisation sub-cellulaire fragilisent l'hypothèse d'un récepteur de surface. Ainsi, nous avons repris la question de la localisation cellulaire du RR/ATP6AP2 endogène. Afin d'étudier la fonction de RR/ATP6AP2 in vivo, nous avons transitoirement supprimer son expression chez le poisson zèbre, et avons généré des rats surexprimant RR/ATP6AP2 dans les cellules musculaires lisses. Nos résultats suggèrent une double fonction pour RR/ATP6AP2, reflétant une possible divergence au cours de l'évolution. La partie C-terminale de la protéine, correspondant au fragment "m 8-9", est très conservée chez les vertébrés et les invertébrés. Ce domaine "ancestral" pourrait être responsable des anomalies du développement précoce observé chez le poisson zèbre et suspecté chez la souris. Cette fonction est clairement indépendante de celle du SRA et pourrait être lié à la fonction de pompe H+ATPase vacuolaire. Le domaine N-terminal de protéine pourrait avoir acquis la capacité de lier la rénine chez les vertébrésThe function of RR/ATP6AP2, described as a new receptor for prorenin/renin, is elusive in vivo. Controversies concerning its subcellular localization are confusing considering the proposed function of vascular cell surface receptor. Here, we readdressed the question of the sub cellular localization of RR/ATP6AP2, focusing on the detection of the endogenous protein. Then we used animal models of gene invalidation and gene overexpression to approach the in vivo function of RR/ATP6AP2. Our results underline that RR/ATP6AP2 might have a dual function possibly reflecting an evolutionary divergence. The RR/ATP6AP2 C-terminal part of the protein, corresponding to the m8-9 fragment, is highly conserved in vertebrates and invertebrates. This "ancestral" domain might account for the early developmental defect observed in zebrafish and suspected in mouse. This function is clearly not related to the renin angiotensin System, and might be linked to the vacuolar H+-ATPase. The N-terminal part of the protein might have acquire a prorenin/renin binding capacity in vertebrates
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Bastian, René. "Characterisation of AtPNP-A - a novel arabidopsis thaliana gene with role in water and salt homeostasis." Thesis, University of the Western Cape, 2009. http://hdl.handle.net/11394/2818.
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Philosophiae Doctor - PhDPlant natriuretic peptides (PNPs) are a novel class of extracellular, systemically mobile molecules that elicit a number of plant responses important in homeostasis and growth. Natriuretic peptides were first identified in vertebrates where they play a role in the regulation of salt and water balance. Subsequent experimental investigations have identified the presence of a natriuretic peptide hormone system in plants. While PNPs have been implicated in various physiological responses such as stomatal guard cell movements and regulation of net water uptake, its biological role has remained elusive. Here we have used co-expression and promoter content analysis tools to understand the biological role of the Arabidopsis thaliana PNP (AtPNP-A). The analysis of AtPNP-A and its co-expressed genes revealed that genes annotated as part of the systemic acquired resistance (SAR) pathway were over-represented, thus suggesting that AtPNP-A may function as a component of plant defense responses and specifically, SAR. The results further show that AtPNP-A shares many characteristics with pathogenesis related (PR) proteins in that its transcription is strongly induced in response to pathogen challenges, thus implying a newly described role for AtPNP-A in pathogen attack. Additional tissue expression analysis also indicated distinct localization of PNP activity in sepals and transcriptional meta-analysis showed that AtPNP-A may play a role in starch breakdown. Therefore, together with the finding that AtPNP-A plays a role in regulating phloem transport, we also hypothesize that AtPNP-A may play a role in phloem unloading in sepals to assist processes such as seed formation in plants. In plants, the second messenger, guanosine 3’,5’-cyclic monophosphate (cGMP) mediates a whole range of important processes including salinity tolerance, disease resistance, drought tolerance and responses to light. Since PNPs regulate water and salt homeostasis via a cGMP-dependent signaling pathways, it is thus important to analyse the transcriptome induced by the second messenger (cGMP) in Arabidopsis thaliana to give a better understanding of its mechanism of action. This study was also supplemented by the analysis of the gibberellic acid (GA) dependent transcriptome, since cGMP also plays a role its transcription pathway. This data analysis, together with promoter content investigation, revealed that genes upregulated after cGMP treatment and down-regulated in the GA insensitive mutant (ga1-3) were enriched with a GA response element (GARE), while no GARE enrichment were observed in genes up-regulated in the ga1-3 mutant. These findings suggest that GARE is indicative of GA-induced and cGMP-dependent transcriptional up-regulation. Gene ontology analysis confirmed previous reports that cGMP is involved in ion homeostasis and indicated that the transcriptional cGMP response is bi-polar in the sense that both genes up- and down-regulated in response to cGMP is involved in cation transport. Additionally, ab initio analysis of genes transcriptionally dependent on cGMP identified CHX8 as a hub gene and promoter content of CHX8 co-expressed genes show enrichment of the GARE motif. The fact that CHX8 has its highest expression levels during male gametogenesis and pollen tube growth, together with our findings, suggest that GA-induced and cGMP- dependent genes may play a key role in ion and water homeostasis in the male gametophyte. Finally, we propose that the type of analysis undertaken here can yield new insights into gene regulation networks and inform experimental strategies to unravel complex transcription regulatory systems under different developmental and stimulus specific conditions.
South Africa
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Goussard, Sébastien. "Etude de la localisation mitochondriale de l'ARNm ATP2 chez Saccharomyces cerevisiae." Paris 7, 2012. http://www.theses.fr/2012PA077113.
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Ma thèse porte sur la traduction localisée d'ARNm à la surface mitochondriale. Le phénomène de traduction localisée fait correspondre le site de traduction d'un ARNm et le site d'action de la protéine produite. 60% des protéines de la mitochondrie codées dans le génome nucléaire ont leur ARNm traduits à la surface de la mitochondrie. Il y a deux classes d'ARNm focalisés à la mitochondrie. Les ARNm de classe I dépendent de la protéine liant l'ARN Puf3p pour être localisés à la mitochondrie mais pas ceux de classe II. L'identification de signaux en cis sur PARNm de ATP2, transcrit de classe II, a été effectuée par une méthode combinant des expériences de FISH et des analyses statistiques rigoureuses des images, permettant de déterminer la proportion de cellules d'une population où cet ARNm est localisé à la mitochondrie. La traduction et le MTS (mitochondrial targetting séquence), ainsi que les régions RI et R2 sont essentielles à la localisation asymétrique de l'ARNm de ATP2. Au cours de ma thèse, j'ai réduit la taille de la région R2 de la moitié du gène ATP2 à ses 200 dernières bases. J'ai pu montré que deux ARNm constitués des mêmes régions codantes mais dans un ordre différent étaient enrichis dans des proportions différentes à la surface mitochondriale. Selon que le gène rapporteur LacZ soit fusionné en 3' ou en 5' du gène ATP2, la proportion de cellules où l'ARNm est localisé passe du simple au double. J'ai effectué des expériences de séparation de polysomes sur gradient de sucrose afin de déterminer la dynamique de traduction de ces ARNm. La traduction des ARNm fortement enrichis dans la fraction mitochondriale semble peu efficaceMy thesis is upon mRNA's localized translation at the proximity of mitochondria. The translation localization phenomena allows an mRNA to be translated at the same site it's protein acts. 60% of nuclear genome encoded mitochondrial proteins are translated on the mitochondrial surface. There is two classes of mRNA localized to mitochondria. Class l's mRNA necessit the RNA binding protein Puf3p to be localized, which is not the case of class IF s mRNA. The identification of cis acting signals in ATP2 mRNA, a class II transcript, has been done using a method combining FISH experiments and statistical analyzes of pictures, allowing the determination of the proportion of cells where the mRNA is localized on mitochondria's surface. The translation, the MTS (mitochondrial targetting sequence) and two regions, RI and R2, are essentials to ATP2's mRNA mitochondrial localization. During my Ph. D, I reduced region R2 size from half ATP2 length to the 200 last bases. I showed that two RNA formed of the same coding regions but in a different order are not enriched in the same proportion in mitochondrial fraction. The proportion of cells where the mRNA is localized to mitochondria double wether the raporter gene LacZ is at the 3' or 5' of ATP2 gene. I've done sucrose gradient polysomes separation experiments to establish the translations dynamic of those mRNA. It seems that the translation of mRNA highly enriched in mitochondria's fraction is less efficient
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Cannata, Serio Magda. "Mutations in V-ATPase assembly factors cause Congenital Disorder of Glycosylation (CDG) with autophagic liver disease Mutations in the X-linked ATP6AP2 cause a glycosylation disorder with autophagic defects Mutations in the V-ATPase assembly factor VMA21 cause a congenital disorder of glycosylation with autophagic liver disease." Thesis, Sorbonne Paris Cité, 2019. https://wo.app.u-paris.fr/cgi-bin/WebObjects/TheseWeb.woa/wa/show?t=2277&f=17696.
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La pompe protonique V-ATPase est un complexe impliqué dans l'acidification intracellulaire. Elle est formée par le secteur V0 pour le transport des protons et le secteur V1 pour l'hydrolyse de l'ATP. Des études pionnières chez S. cerevisiae montrent que l'assemblage du secteur V0 commence dans le réticulum endoplasmique (ER) grâce au contrôle de 5 facteurs d'assemblage: Vma21p, Vma12p, Vma22p, Pkr1p et Voa1p. Une fois assemblé, le secteur V0 est transporté par Vma21p jusqu'au cis-Golgi, où, avec le secteur V1, constitue un holoenzyme fonctionnel. Ce processus chez l'homme n¿est pas encore clair. Il a été récemment démontré que tous les facteurs d'assemblage, à l'exception de Pkr1p, sont conservés chez l'homme et que des mutations chez trois d'entre eux, ATP6AP1, TMEM199 et CCDC115, sont responsables d'un nouveau sous-groupe d'anomalies congénitales de la glycosylation (CDG). Dans la première partie de ma thèse, j'ai identifié des mutations faux-sens dans ATP6AP2, qui provoquent une CDG similaire, avec des anomalies de la glycosylation, une stéatose du foie et des anomalies cognitives et immunitaires. Auparavant, des mutations exon-skipping dans ATP6AP2 avaient été associées à une maladie cérébrale d'apparition tardive, avec du parkinsonisme et de l'épilepsie. Nos travaux ont révélé que les mutations faux-sens dans ATP6AP2 conduisent à une activité défectueuse de la V-ATPase, avec réduction de l'acidification organellaire, de la dégradation lysosomale et du flux autophagique. De ce fait, la clairance des gouttelettes lipidiques ne peut pas se produire dans les autolysosomes, produisant une stéatose dans le foie des patients. Conformément au phénotype clinique similaire, nous avons constaté que ATP6AP2 interagissait avec les facteurs d'assemblage du secteur V0, tandis que les mutations faux-sens en réduisaient l'interaction, suggérant un assemblage compromis chez les patients. En revanche, chez les patients présentant une mutation exon-skipping, nous avons trouvé une glycosylation normale des protéines sériques et aucun effet sur l'interaction entre ATP6AP2 et ATP6AP1, ce qui suggère que les mutations faux-sens ont un impact plus fort sur la fonction globale de ATP6AP2 que celles exon-skipping. Ces résultats révèlent des nouveaux aspects de l'assemblage de la V-ATPase dans l'ER et suggèrent que ATP6AP2 est un membre supplémentaire des facteurs d'assemblage chez l'homme. Dans la deuxième partie de ma thèse, j'ai démontré que des mutations dans VMA21 sont également à l'origine d'une CDG associée à une maladie du foie, avec un phénotype similaire aux autres déficits en facteur d'assemblage de la V-ATPase. Auparavant, des mutations en VMA21 étaient associées à une myopathie X-linked avec une autophagie excessive (XMEA), une vacuolisation progressive et une atrophie du muscle squelettique. En utilisant des fibroblastes de patients, nous avons testé l'impact fonctionnel de ces mutations sur l'assemblage et la fonction de la V-ATPase. Les mutations de VMA21 sont hypomorphes, réduisant l'expression de l'ARNm et de la protéine, et provoquent des défauts de l'autophagie avec une moindre dégradation des gouttelettes lipidiques, similaires à ce qui a été observé dans la déficience en ATP6AP2. Enfin, les fibroblastes des patients montrent une accumulation de cholestérol non estérifié dans des vésicules, similaire à celle observée dans la maladie de surcharge lysosomale Niemann-Pick de type C (NPC). La séquestration du cholestérol dans les lysosomes active la lipogenèse via la protéine SREBP, ce qui conduit à une hypercholestérolémie chez les patients. Globalement, nos résultats montrent que les déficiences de la V-ATPase constituent un nouveau groupe de syndromes métaboliques qui affectent l'homéostasie lysosomale et autophagique. L'étude de ces maladies rares permettra de mieux comprendre la pathogénie de la stéatose hépatique non alcoolique (NAFLD), un problème fréquent dans le syndrome métaboliqueThe V-ATPase is a large complex involved in the acidification of intracellular organelles. It is formed by a proton pore (V0 sector) and ATP hydrolysis domain (V1 sector). Pioneering studies in S. cerevisiae have shown that the assembly of the V0 sector occurs in the endoplasmic reticulum (ER) under the guidance of 5 assembly factors: Vma21p, Vma12p, Vma22p, Pkr1p and Voa1p. The newly assembled V0 sector is then escorted by Vma21p to the cis-Golgi, where it will bind the V1 sector to constitute a functional holoenzyme. How the assembly works in mammalian systems is currently still unclear. Yet, it was recently shown that all the assembly factors except Pkr1p are conserved in mammals and that mutations in three of them, ATP6AP1, TMEM199 and CCDC115, were identified to cause a new subgroup of congenital disorders of glycosylation (CDG). Using human genetics and functional validation, I identify in the first part of my thesis a novel mammalian assembly factor called ATP6AP2 that causes a similar CDG-like disease when mutated. Apart from glycosylation defects, patients with missense mutations in ATP6AP2 show steatotic liver disease, cognitive defects and immune defects. Previously exon-skipping mutations in ATP6AP2 had been associated with a late onset cerebral disease, with Parkinsonism and epilepsy. Our work revealed that ATP6AP2 missense mutations lead to defective V-ATPase activity, subsequently causing reduced organellar acidification, lysosomal degradation and autophagic flux. Because of this, clearance of lipid droplets cannot take place in the autolysosomes, giving rise to the steatotic phenotype in the patients hepatocytes. Consistent with the similar clinical phenotype, we found that ATP6AP2 interacts with V0 assembly factors, while the missense mutations reduced the interaction, suggesting a compromised V-ATPase assembly in the patients. By contrast, in patients with exon-skipping mutation we found normal glycosylation of serum proteins and no effect on the interaction between ATP6AP2 and ATP6AP1, suggesting that the missense mutations have a stronger impact on overall ATP6AP2 function than the exon-skipping ones. These results shed light on the V-ATPase assembly in the ER and suggest that ATP6AP2 is an additional mammalian member of the assembly factors. In the second part of my thesis, I demonstrate that mutations in VMA21 also cause CDG with liver disease. Previously, mutations of VMA21 had been associated with an X-linked myopathy with excessive autophagy (XMEA), characterized by progressive vacuolation and atrophy of skeletal muscle. Yet, we were able to identify VMA21 mutations with a similar clinical phenotype compared to the other V-ATPase assembly factor deficiencies. Using patient fibroblasts, we tested the functional impact of the newly identified VMA21 mutations on V-ATPase assembly and function, with the attempt to highlight the differences between with the XMEA ones. First, we could show that VMA21 mutations are hypomorphic and reduce both Vma21 mRNA and protein expression. Second, VMA21 mutations cause autophagic defects with decreased lipid droplet degradation, similar to those observed in ATP6AP2-deficient cells. Finally, VMA21 fibroblasts showed an accumulation of unesterified cholesterol in vesicular structures, similar to what has been reported for the lysosomal storage disease Niemann-Pick type C (NPC). The sequestration of cholesterol in lysosomes triggers lipogenic pathways mediated by the sterol response element-binding protein (SREBP), most likely leading to hypercholesterolemia in the patients. Altogether, our results show that V-ATPase deficiencies are a novel group of metabolic syndromes that affect lysosomal/autophagic homeostasis. Studying these rare V-ATPase assembly disorders that are featured by liver steatosis as a unifying pathology may lead to a better understanding of the pathogenesis of non-alcoholic fatty liver disease (NAFLD), which is a common problem in metabolic syndrome
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Trivilin, Ana Paula. "Superexpressão do gene codificante do peptídeo AtPep1 em A.Thaliana visando a obtenção de resistência à isolados de diferentes espécies do gênero Pythium." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/15865.
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As plantas estão expostas a uma gama de patógenos que utilizam diversas estratégias para infectar seus hospedeiros. Em resposta, as plantas expressam diferentes mecanismos de defesa, onde ocorre o reconhecimento de moléculas conservadas do patógeno por receptores específicos das plantas, desencadeando as respostas de defesa. A descoberta de sinais endógenos e exógenos que regulam a expressão de genes de defesa em Arabidopsis thaliana tem auxiliado a compreensão dos mecanismos de defesa. O desenvolvimento de uma estratégia de superexpressão para avaliação do papel do peptídeo endógeno AtPep1 na resistência a isolados de diferentes espécies do gênero Pythium é importante para a compreensão do mecanismo de defesa e a futura utilização do mesmo em cultivares resistentes ao patógeno. Nesse sentido, foram realizados experimentos que consistiram da inoculação de A. thaliana com isolados das espécies de P. graminicola, P. inflatum, P. deliense e P. ultimum. As plantas foram avaliadas quanto à presença de sintomas da doença. Paralelamente, o gene codificante do peptídeo AtPep1, PROPEP1, foi isolado de A. thaliana, ligado nos vetores binários pGSA1427 ou pEGAD, e transformados em Agrobacterium tumefaciens. Células de A. tumefaciens contendo os plasmídeos com e sem PROPEP1 foram usadas para transformação floral de A. thaliana. As plantas transformadas foram selecionadas pela presença do gene que confere tolerância ao herbicida glufosinato de amônio e, no caso da planta transformada com o vetor pEGAD, também pela presença da GFP (proteína verde fluorescente). A presença dos genes inseridos foi confirmada por PCR seguido de seqüenciamento. As plantas transformadas foram avaliadas quanto ao acúmulo de mRNA de PROPEP1 e a resistência aos isolados do gênero Pythium. Os resultados indicam que plantas tipo selvagem de A. thaliana são suscetíveis aos isolados das diferentes espécies do gênero Pythium. As plantas pEGAD-AtPep apresentaram um aumento na expressão relativa de PROPEP1 de até 4.000 vezes a encontrada nas plantas controle. Este alto acúmulo de PROPEP1 nas plantas pEGAD-AtPep e pGSAAtPep revelou ser importante na resistência ao isolado de P. deliense. As evidências suportam o papel do peptídeo AtPep1 como um elicitor endógeno que é gerado em resposta aos patógenos e suas PAMPs.Plants are exposed to a range of pathogens that use several strategies to infect their host. In response, the plants express different mechanisms of defense, in which the recognition of conserved pathogen molecules by plant specific receptors triggers the defence responses. The discovery of exogenous and endogenous signals that regulate the expression of defense genes in Arabidopsis thaliana has helped the understanding of the mechanisms of defense. The development of a strategy of overexpression for evaluating the role of endogenous peptide AtPep1 in resistance to isolates of different species of the genus Pythium is important for understanding the mechanism of defense and its future use in resistant cultivars to the pathogen. Therefore, experiments that were performed consisted in the inoculation of A. thaliana with isolates of the of P. graminicola, P.inflatum, P. deliense, and P. ultimum species. The plants were evaluated for the presence of disease symptoms. In addition to that, the gene coding the peptide AtPep1, PROPEP1 was isolated from A. thaliana, ligated in the binary vectors pGSA1427 or pEGAD, and transformed in Agrobacterium tumefaciens. Cells of A. tumefaciens containing the plasmids with or without PROPEP1 were used to floral transformation of A. thaliana. The transformed plants were selected for the presence of the gene that confers tolerance to the herbicide ammonium glufosinate and, in the case of plants transformed with the vector pEGAD, they were also selected for the presence of GFP (green fluorescent protein). The presence of the inserted gene was confirmed by PCR followed by sequencing. The transformed plants were evaluated on the accumulation of mRNA from PROPEP1 and resistance to isolates of the genus Pythium. The results indicate that A. thaliana wild type plants are susceptible to isolates from various species of the genus Pythium. The pEGAD-AtPep plants showed an increase in the expression of PROPEP1 of up to 4.000 times more than that was found in control plants. Such high accumulation of PROPEP1 in pEGAD-AtPep and pGSA-AtPep plants was shown to be important in resistance to the isolate of P. deliense. The evidences support the role of the peptide AtPep1 as an endogenous elicitor that is generated in response to pathogens and their PAMPs.
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Rousselle, Anthony [Verfasser], Michael [Gutachter] Bader, Achim [Gutachter] Leutz, and Uwe [Gutachter] Kornak. "Role of the (Pro)renin Receptor [(P)RR/ATP6ap2] in Osteoclast and Macrophage Physiology / Anthony Rousselle ; Gutachter: Michael Bader, Achim Leutz, Uwe Kornak." Berlin : Humboldt-Universität zu Berlin, 2017. http://d-nb.info/1189328143/34.
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Thomazella, Maria Cristina Dias. "Efeito da dieta tipo Mediterrânea na função endotelial e inflamação da aterosclerose: estudo comparativo com a dieta TLC (\"Therapeutic Lifestyle Changes\", no NCEP-ATPIII)." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/5/5131/tde-24062010-143245/.
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A dieta Mediterrânea (DM) tem sido amplamente estudada do ponto de vista epidemiológico porém, o efeito pleno específico da DM, bem como os mecanismos pelos quais esse padrão dietético contribui para redução do risco cardiovascular em prevenção secundária, são desconhecidos. Isso ocorre, em parte, devido à dificuldade de aderência observada em ensaios clínicos de intervenção dietética, especialmente estudos comparativos com dietas hipolipemiantes, por exemplo, a dieta TLC, Therapeutic Lifestyle Changes Diet (TLCD) do National Cholesterol Education Program-ATPIII. Assim, realizamos um estudo clínico, controlado, não randomizado, comparando o perfil de risco cardiovascular de dieta Mediterrânea (DM) versus dieta TLC (DTLC) em 40 pacientes com doença arterial coronariana, homogeneamente selecionados (45-65 anos de idade, homens, que tiveram ao menos um evento coronariano nos 2 últimos anos) e intensamente medicados. Uma questão paralela foi entender os efeitos de ambas as dietas nos processos de inflamação, disfunção endotelial e do estresse oxidativo, fatores-chave na aterogênese e particularmente importantes na prevenção secundária. Os hábitos culturais e dietéticos foram relevantes para alocação dos pacientes nos grupos de dieta Mediterrânea (n = 21; dieta rica em grãos integrais, vegetais, frutas, oleaginosas 10 g/dia, azeite de oliva extra-virgem 30 g/dia e vinho tinto 250 ml/dia) ou dieta TLC (n = 19; suplementada com fitosteróis 2g/dia através de creme vegetal 20 g/dia). Escores de aderência validados na literatura e específicos às dietas mostraram resultado > 90% no índice de aderência aos dois padrões dietéticos. Alguns efeitos foram comuns à dieta Mediterrânea e à dieta TLC. Com ambas, houve redução significativa de peso, índice de massa corporal (kg/m²), variáveis de composição corporal e pressão arterial. Além disso, ambas as dietas promoveram redução dos níveis plasmáticos de ADMA e da relação L-arginina/ADMA. A reatividade da artéria braquial dependente do endotélio permaneceu inalterada em ambos os grupos; no entanto, pacientes sob DM e sob DTLC melhoraram a velocidade de fluxo no momento basal (pré-hiperemia vascular). Outros efeitos foram específicos a cada padrão dietético. Com a DM, foram observados diminuição na contagem total de leucócitos versus DTLC (p =0.025) e aumento nos níveis de HDL-colesterol em 3 mg/dL (p = 0.053) versus DTLC, que mantiveram níveis de HDL-C inalterados. O diâmetro basal da artéria braquial aumentou com a DM, mas não com a DTLC. Com a DTLC, houve redução estatisticamente significante versus DM nas variáveis lipídicas colesterol total, LDL-colesterol (p < 0.05) e LDL oxidada (p = 0.009), embora a razão LDL oxidada/LDL total não tenha se alterado. Níveis séricos/plasmáticos de apolipoproteína A-1, lipoproteína(a), glicose, mieloperoxidase, sICAM, sVCAM, e as razões glutationa reduzida/oxidada em plasma e eritrócitos não se alteraram em ambos os grupos. Em conjunto, estes dados indicam um perfil de efeitos da DM e DTLC compatíveis com redução do risco cardiovascular, mesmo em pacientes intensamente medicados, em prevenção secundária. Embora estes efeitos tenham sido equivalentes entre DM e DTLC, eles parecem ser mediados tanto por alguns mecanismos comuns, como alguns mecanismos específicos de cada dietaThe Mediterranean Diet (MD) has been widely studied with respect to epidemiology, but mechanisms whereby the Mediterranean Diet (MD) is cardioprotective are unclear. This is partly because of the difficulties of adherence in clinical trials of dietary intervention, particularly trials comparing it to traditional lipid-restraining diets, e.g., Therapeutic Lifestyle Changes Diet (TLCD) from National Cholesterol Education Program ATPIII. We performed a controlled, non-randomized clinical trial comparing the cardiovascular risk profile of the Mediterranean Diet (MD) versus the TLC Diet (TLCD) in 40 selected, highly-homogeneous, and intensively medicated patients with coronary heart disease (45-65 years, males, at least one coronary event over prior 2 years). In addition, we sought to investigate both diets effects on inflammation, endothelial dysfunction and oxidative stress, all key factors in atherogenesis and particularly important in secondary prevention. Dietary/cultural habits were the basis to allocate patients for 3 months to either MD (n = 21; rich in whole grains, vegetables, fruits, nuts 10g/day, extra-virgin olive oil 30g/day, red wine 250ml/day) or TLCD (n = 19; plus phytosterols 2g/day). Specific scores showed that both diets had >90% adherence. Some effects were common to both diets. Patients in both groups showed a significant reduction in weight, body mass index, body composition and blood pressure. Also, both groups presented a reduction in plasma levels of ADMA and L-arginine/ADMA ratio. Endothelial-dependent brachial artery reactivity remained unaltered in both groups. However, patients under MD and TLCD improved flow velocity at baseline (prior to hyperemia). Nevertheless, other effects were specific to each diet. With MD, there was significant decrease in leukocyte count vs. TLCD (p = 0.03) and average increase in HDL-cholesterol by 3 mg/dL (p = 0.053) versus TLCD. The brachial arterials basal diameter increased with MD but not with TLCD. However, with TLCD there was a statistically significant reduction of lipid variables: total cholesterol, LDL-cholesterol (p < 0.05) and oxidized LDL (p = 0.009) vs. MD even though the ratio of oxidized / total LDL remained unaltered. Plasma and serum levels of apolipoprotein A-1, lipoprotein(a), glucose, myeloperoxidase, sICAM, sVCAM, and glutathione reduced/oxidized ratio in plasma and erithrocytes also remained unaltered in both groups. Together, these results demonstrate a pattern of effects of MD and TLCD compatible with cardiovascular risk reduction, in secondary prevention, even in intensely medicated patients. Although these effects were equivalent between MD and TLCD, they seem to be mediated by some common mechanisms, as well as by each diets specific mechanisms
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Suifan, Taghrid. "Team effectiveness : a test of in-put process-output." Thesis, Aston University, 2010. http://publications.aston.ac.uk/19120/.
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This research addressed the question: "Which factors predict the effectiveness of healthcare teams?" It was addressed by assessing the psychometric properties of a new measure of team functioning with the use of data collected from 797 team members in 61 healthcare teams. This new measure is the Aston Team Performance Inventory (ATPI) developed by West, Markiewicz and Dawson (2005) and based on the IPO model. The ATPI was pilot tested in order to examine the reliability of this measure in the Jordanian cultural context. A sample of five teams comprising 3-6 members each was randomly selected from the Jordan Red Crescent health centers in Amman. Factors that predict team effectiveness were explored in a Jordanian sample (comprising 1622 members in 277 teams with 255 leaders from healthcare teams in hospitals in Amman) using self-report and Leader Ratings measures adapted from work by West, Borrill et al (2000) to determine team effectiveness and innovation from the leaders' point of view. The results demonstrate the validity and reliability of the measures for use in healthcare settings. Team effort and skills and leader managing had the strongest association with team processes in terms of team objectives, reflexivity, participation, task focus, creativity and innovation. Team inputs in terms of task design, team effort and skills, and organizational support were associated with team effectiveness and innovation whereas team resources were associated only with team innovation. Team objectives had the strongest mediated and direct association with team effectiveness whereas task focus had the strongest mediated and direct association with team innovation. Finally, among leadership variables, leader managing had the strongest association with team effectiveness and innovation. The theoretical and practical implications of this thesis are that: team effectiveness and innovation are influenced by multiple factors that must all be taken into account. The key factors managers need to ensure are in place for effective teams are team effort and skills, organizational support and team objectives. To conclude, the application of these findings to healthcare teams in Jordan will help improve their team effectiveness, and thus the healthcare services that they provide.
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Schäfer, Simon Thomas [Verfasser]. "ATP6AP2 is critically involved in adult hippocampal neurogenesis and reveals stage-specific functions for Wnt/ß-Catenin and Wnt/Planar Cell Polarity (PCP) signaling / Simon Thomas Schäfer." Greifswald : Universitätsbibliothek Greifswald, 2015. http://d-nb.info/1069389331/34.
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Heinz, Anja [Verfasser]. "Die Bedeutung von AtpI für die F1Fo-ATPase in Escherichia coli und Cupriavidus metallidurans / Anja Heinz." Halle, 2017. http://d-nb.info/1142920488/34.
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Dau, Andressa Minussi Pereira. "Sistema renina-angiotensina nas células da teca e granulosa durante a ovulação e luteinização em bovinos." Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/11578.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESThe objective of present study was to investigate (Pro)renin receptor function in the theca and granulosa cells during the preovulatory period and luteinization in cattle. During the initial preovulatory period, prorenin induced the resumption of oocyte meiosis even in the presence of follicular hemisections or forskolin. In granulosa cells, pró-renina did not increase LHinduced epiregulin (EREG) mRNA after 6 h of culture. Treatment with prorenin plus LH increased amphiregulin (AREG) and prostaglandin synthase 2 (PTGS2) mRNA in granulosa cells. The absence of prorenin effect to stimulate EREG, AREG, and PTGS2 in granulosa cells was established using different combinations of treatments with prorenin and/or aliskiren ([P]RR inhibitor) and/or LH. Treatment of granulosa cells with LH plus EGFR antagonist (AG1478) did not regulate prorenin and (P)RR after 6 h of culture. This result was confirmed in vivo using a model of intrafollicular treatment with AG1478 and intramuscular treatment with GnRH. Finally, (P)RR protein and transcripts for prorenin and pro-fibrotic genes increased in the granulosa cells from 12 h post-GnRH. In the theca cells, (P)RR mRNA and protein increased 6 h after treatment of cows with GnRH. The LH effect to stimulate (P)RR transcript was confirmed in vitro. Intrafollicular treatment with aliskiren did not reduce the ovulation rate. In cultured theca cells, AREG and EREG mRNA were not significantly expressed and ADAM17 was not stimulated by prorenin. Intrafollicular injection of AG1478 did not regulate LH-induced (P)RR, although increased CYP17A1 protein. Prorenin did not induce androstenedione and testosterone synthesis in cultured theca cells. In the corpus luteum, prorenin and (P)RR mRNA were increased at day 10 of estrous cycle compared to day 5, but were not regulated by prostaglandin in vivo, as observed for profibrotic genes. Intrafollicular treatment with aliskiren reduces serum progesterone levels in cows that ovulated. Prorenin role in progesterone synthesis through (P)RR was also evidenced in vitro. Moreover, prorenin induced ERK1/2 phosphorylation in luteal cells, although ERK1/2 inhibition (PD0325901) did not completely inhibit prorenin-induced progesterone synthesis, as evidenced using AG1478. In summary, these results demonstrate that prorenin and (P)RR are stimulated by LH at the end of the preovulatory period and, therefore, they are not related to genes regulated by LH at the initial ovulatory process in granulosa cells; (P)RR is stimulated by LH in the theca cells independently of EGFR; and prorenin stimulate progesterone synthesis through (P)RR, which involves ERK1/2 and EGFR participation. In conclusion, (P)RR is upregulated in granulosa and theca cells after gonadotropins peak and prorenin/(P)RR play an important role in the resumption of oocyte meiosis and on progesterone synthesis in the corpus luteum in cattle.
O objetivo do presente trabalho foi investigar a função do receptor de (pro)renina [(P)RR] nas células da teca e da granulosa durante o período pré-ovulatório e luteinização em bovinos. No início do período pré-ovulatório, pró-renina reiniciou a meiose oocitária bloqueada tanto pelas metades foliculares, quanto por forscolina. Nas células da granulosa, pró-renina não aumentou a expressão de RNAm para epirregulina (EREG) que foi induzido por LH após 6 horas de cultivo. Pró-renina mais LH aumentaram a expressão de RNAm para anfirregulina (AREG) e prostaglandina endoperoxidase sintetase-2 (PTGS2). Contudo, a ausência do efeito de prórenina para estimular o RNAm para EREG, AREG e PTGS2 nas células da granulosa foi evidenciada utilizando as diferentes combinações de tratamento com pró-renina e/ou alisquireno [inibidor do (P)RR] e/ou LH. O tratamento das células da granulosa com LH e antagonista de EGFR (AG1478) não regularam o RNAm para pró-renina e (P)RR após 6 horas de cultivo. Esse resultado foi confirmado in vivo, utilizando um modelo de tratamento intrafolicular com AG1478 e GnRH intramuscular em vacas. Por fim, (P)RR e o RNAm para pró-renina e genes prófibróticos aumentaram nas células da granulosa a partir das 12 horas após tratamento de vacas com GnRH. Nas células da teca, a expressão de (P)RR aumentaram 6 horas após tratamento de vacas com GnRH. O estimulo de LH sobre o transcrito de (P)RR foi confirmado in vitro. O tratamento intrafolicular com alisquireno não reduziu a taxa de ovulação. No nosso cultivo de células da teca, a expressão de RNAm para AREG e EREG não foi significativa e ADAM17 não foi estimulado por pró-renina. Injeção intrafolicular com AG1478 não regulou (P)RR estimulado por LH, mas aumentou a proteína para CYP17A1. Pró-renina não induziu a síntese de androstenediona e testosterona no nosso sistema de cultivo. No corpo lúteo, RNAm para pró-renina e (P)RR foi aumentado no dia 10 do ciclo estral comparado ao dia 5 e não foram regulados por prostaglandina in vivo, como observado para os genes pró-fibróticos. O tratamento intrafolicular com alisquireno diminuiu os níveis de progesterona plasmática em vacas que ovularam. O papel de pró-renina na síntese de progesterona através de (P)RR também foi evidenciado in vitro. Ainda, pró-renina induziu a phosphorilação de ERK1/2 nas células luteais, embora o bloqueio de ERK1/2 (PD0325901) não inibiu completamente a síntese de progesterona induzida por pró-renina, como evidenciado pelo uso de AG1478. Em resumo, esses resultados demonstram que pró-renina e (P)RR são estimulados por LH no final do período pré-ovulatório e, portanto, não estão relacionados com os genes regulados por LH no início do processo ovulatório nas células da granulosa; (P)RR é estimulado por LH nas células da teca de forma independente de EGFR; e a pró-renina estimula a síntese de progesterona via (P)RR envolvendo a participação de ERK1/2 e EGFR neste processo. Em conclusão, (P)RR é regulado positivamente nas células da granulosa e da teca após o pico de LH e a pró-renina/(P)RR possui um importante papel no reinicio da meiose oocitária e na síntese de progesterona pelo corpo lúteo em bovinos.
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Vogel, Lukas Hermann [Verfasser], Jörg [Akademischer Betreuer] Peters, Jörg [Gutachter] Peters, and Sigrid [Gutachter] Hoffmann. "Einfluss der (Pro)Renin Rezeptor ((P)RR, ATP6ap2) Downregulation auf primäre Zilien und den Zellzyklus in As4.1 Zellen / Lukas Hermann Vogel ; Gutachter: Jörg Peters, Sigrid Hoffmann ; Betreuer: Jörg Peters." Greifswald : Universität Greifswald, 2021. http://d-nb.info/1230552936/34.
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Drager, Robert Gray. "Structure and transcript processing of a Euglena gracilis chloroplast operon encoding genes rps2, atpI, atpH, atpF, atpA and rps18." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186334.
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A 9.8 kbp region of the Euglena gracilis chloroplast genome has been cloned, sequenced and analyzed. This region contains six genes, rps2, rps18, atpI, atpH, atpF and atpA which encode ribosomal proteins S2 and S18 and ATP synthase subunits CFₒIV, CFₒIII, CFₒI and CF₁α, respectively. The linear order of these genes, 5'-rps2-atpI-atpH-atpF-atpA-rps18-3', is similar to that of land plant chloroplasts. These six genes are co-transcribed with two tRNA genes which are 5' to rps2. A fully spliced, 5.5 kb transcript containing all six genes accumulates. The spliced hexa-cistronic transcript is processed by intercistronic cleavage to mono-cistronic mRNAs. The 5' ends of the accumulated mono-cistronic transcripts map to single-stranded regions of the most stable secondary structure for each intercistronic sequence. There is no evidence for initiation of transcription in this region of the Euglena gracilis chloroplast genome. This Euglena chloroplast operon is interrupted by 17 introns. Nine of the introns are group III and seven are group II. All of the group III introns have potential secondary structures near their 3' ends which resemble domain VI of group II introns. The remaining intron is a complex twintron excised as four group III introns. This intron is comprised of two group III introns within the internal intron of a group III twintron. Two of the internal introns are excised from multiple splice sites. Two of the internal introns interrupt the domain VI-like structure of the host group III intron. The 16S rRNA sequence of Euglena chloroplasts is phylogenetically related to the 16S rRNA sequence of chromophyte chloroplasts, while the Euglena derived atpA amino acid sequence is more closely related to atpA sequences of chlorophyte chloroplasts than to atpA sequences of chromophyte chloroplasts. Too few chloroplast ribosomal protein sequences are available in the databases to perform meaningful phylogenetic analysis of rps2 or rps18. Although clustering of rps2 with the ATP synthase genes in chloroplasts of chlorophytes, rhodophytes, chromophytes and euglenophytes, but not prokaryotes, is evidence that chloroplasts are of mono-phyletic origin.
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Morch, Anica [Verfasser], Jörg [Akademischer Betreuer] Peters, Michael [Gutachter] Bader, and Jörg [Gutachter] Peters. "Die Lokalisation des (Pro)Reninrezeptors in renalen, kardialen und neuronalen Zellen und Geweben sowie seine Funktion als akzessorisches Protein ATP6ap2 der vakuolären H+-ATPase / Anica Morch ; Gutachter: Michael Bader, Jörg Peters ; Betreuer: Jörg Peters." Greifswald : Universität Greifswald, 2019. http://d-nb.info/1195140894/34.
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Carreño, Oriel. "Anàlisi genètica i funcional de la migranya hemiplègica i la migranya comuna." Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/85723.
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Aquesta tesi es centra en la genètica de la migranya. La migranya comuna és un trastorn neurològic caracteritzat per episodis recurrents de mal de cap. Els criteris de la IHS (International Headache Society) subclasifiquen la malaltia en migranya amb aura (MA) i migranya sense aura (MO). L'aura són símptomes neurològics transitoris que poden acompanyar el mal de cap. Les aures més freqüents són les aures visuals, tot i que també existeixen les aures sensorials essent l'aura hemiplègica la seva forma severa. La nostra investigació es va dividir en dues areas d'acord amb la base genètica dels trastorns, d'una banda, s'ha estudiat la genètica complexa de la migranya comuna, d'altra banda s'ha estudiat una forma rara de la migranya que presenta una herència mendeliana anomenada migranya hemiplègica familiar (FHM).
Per entendre més la base genètica de la migranya comuna es va utilitzar un estudi d'associació tipus cas-control amb gens candidats. Amb aquesta finalitat es van seleccionar al voltant de 550 pacients amb migranya (MA i MO) i el seu corresponent grup de control. Per tal d'analitzar la seva implicació en la susceptibilitat genètica a la migranya, es van triar gens que codifiquen per als canals de la superfamília heterogeni de potencial receptor transitori (Transient Receptor Potential- TRP) que se sap que estan implicats en les vies nociceptives. Aquesta feina ha donat lloc a una publicació (Carreño et al. SNP variants within the vanilloid TRPV1 and TRPV3 receptor genes are associated with migraine in the Spanish population. Am J Med Genet B Neuropsychiatr Genet. 2012).
En el cas particular de les formes monogèniques de FHM es coneixen tres gens involucrats en la malatia (CACNA1A, ATP1A2 i SCN1A), les proteïnes codificades per aquests gens tenen un paper rellevant en la neurotransmissió del glutamat. L'anàlisi funcional de les mutacions que causen FHM han mostrat en última instància un augment de l'alliberament de la neurotransmissió. En el cas de mutacions al CACNA1A s'ha vist un efecte de guany de funció, a diferència de les mutacions al ATP1A2 que presenten un efecte de pèrdua de funció. En aquest treball s'ha fet un screening mutacional per identificar mutacions en pacients per seqüenciació directa. Quan les mutacions eren suficientment interessants s'han generat construccions en vectors d'expressió per subseqüents estudis funcionals en cèl·lules eucariotes. Aquesta feina ha donat lloc a tres publicacions. A la primera (Serra et al. A mutation in the first intracellular loop of CACNA1A prevents P/Q channel modulation by SNARE proteins and lowers exocytosis. Proc Natl Acad Sci. 2010) es va identificar un canvi que modula la funció del canal de CACNA1A. Aquest estudi ajuda a explicar la contribució genètica en la heterogeneïtat clínica d'una família i a entendre millor el mecanisme molecular dels canals de calci tipus P/Q. El segon (Carreño et al. Acute striatal necrosis in hemiplegic migraine with the novo CACNA1A mutation. Headache. 2011) és un informe d'un pacient que presenta una necrosi aguda stratial. Té una rellevància clínica a causa de l'aparició primerenca dels símptomes neurològics previs als atacs hemiplègics. El tercer i últim treball (Carreño et al. Screening of the ATP1A2 and CACNA1A genes in patients with hemiplegic migraine: clinical, genetic and functional studies. [work in progress]) recull l'screening mutacional al gens ATP1A2 i CACNA1A en 19 pacients amb FHM. Es van identificar 5 mutacions prèviament descrites i dues mutacions noves.This Thesis is focused in migraine genetics, migraine is a prevalent neurological disorder characterized by recurrent episodes of headache. This research was divided in two areas according to the genetic basis of the disorders; on the one hand we studied the common migraine with a complex genetics, on the other hand we studied the rare mendelian forms of familial hemiplegic migraine (FHM). To understand more the genetic basis of the common migraine a case-control association study approach was used with candidate genes. For that purpose, around 550 patients with migraine and their corresponding control group were selected. In order to analyze their involvement in the genetic susceptibility to migraine, we chose genes encoding for channels of the heterogeneous superfamily of Transient Receptor Potential (TRP) which are known to be involved in the nociceptive pathway. In the particular case of FHM, a monogenic form of the disorder, there are three genes known to be involved in the FHM (CACNA1A, ATP1A2 and SCN1A), whose encoded proteins are playing a relevant role in the neurotransmission of the glutamate. Functional analysis of the mutations causing FHM have shown ultimately an increased neurotransmission release. CACNA1A previous studies reveled a gain-of-function effect from FHM mutations, unlike mutations on ATP1A2 that present a loss-of-function effect. Our work consisted on identifying mutations in patients by direct sequencing. If the mutations were interesting enough vector constructions were generated for functional studies in eukaryotic cells. This work gave rise to three publications: First; the identification of a change that modulates the function of the CACNA1A channel. This study contributes to explain the genetic contribution in the clinical heterogeneity of one family and to know more about the molecular mechanism of the P/Q calcium channel. Second; a report of a patient that presents an acute stratial necrosis that had clinical relevance because of the early onset of the neurological symptoms previous to the hemiplegic attacks. Third; a mutational screening of ATP1A2 and CACNA1A genes in 19 patients with FHM. 5 previously described mutations and two new mutations were found. Functional studies were carried out for the newly mutations.
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Liu, Li. "Roles of PMCA Isoforms in Ca2+-Homeostasis and Contractility of Bladder Smooth Muscle: Evidence from PMCA Gene-Ablated Mice." Cincinnati, Ohio : University of Cincinnati, 2007. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1178307168.
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Thesis (Ph.D.)--University of Cincinnati, 2007.Advisor: Richard J. Paul. Title from electronic thesis title page (viewed Apr. 4, 2009). Keywords: PMCA (human gene symbols; ATP2B); SERCA2 (human gene symbols; ATP2A2); NCX; bladder smooth muscle; Ca²⁺ homeostasis; gene-altered mice. Ca²⁺ waves; Ca²⁺ sparks; Fura-PE3; Fluo-4; Indo-1; multi-photon microscopy. Includes abstract. Includes bibliographical references.
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Heckwolf, Marlies. "Funktionelle Charakterisierung der Arabidopsis thaliana Aquaporine AtPIP1;2 und AtPIP2;3." Phd thesis, 2010. https://tuprints.ulb.tu-darmstadt.de/2042/1/Dissertation_neu.pdf.
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Die pflanzlichen Aquaporine der Plasmamembran intrinsischen Proteine (PIP) lassen sich in zwei Untergruppen einteilen, die PIP1 und PIP2 Aquaporine. Obwohl diese beiden Gruppen ähnliche Porenregionen aufweisen unterscheiden sie sich in ihrer Leitfähigkeit für Wasser und kleinere Moleküle. Im Vergleich zur hohen Wasser-Leitfähigkeit von PIP2- Aquaporinen, sind PIP1-Aquaporine nahezu wasserundurchlässig. Im Gegensatz dazu können PIP1-Aquaporine die Diffusion von kleinen, ungeladenen Molekülen (Glycerin, Harnstoff, CO2) erleichtern, PIP2-Aquaporine jedoch nicht. Im Rahmen dieser Arbeit sollten die Leitfähigkeitscharakteristika der Aquaporine AtPIP1;2 und AtPIP2;3 aus Arabidopsis thaliana in einem Hefeexpressionssystem mit Hinblick auf ihre Wasser-und Kohlendioxid-Leitfähigkeit untersucht und im Anschluss ihre physiologische Bedeutung für die Pflanze analysiert werden. Es zeigte sich, dass AtPIP2;3 die Membranpermeabilität für Wasser signifikant erhöhen konnte, wohingegen AtPIP1;2 dies nicht vermochte. Im Gegensatz dazu war AtPIP1;2 in der Lage, die Diffusion von CO2 über die Hefe-Plasmamembran zu erleichtern, AtPIP2;3 jedoch nicht. Die physiologische Relevanz dieser verschiedenen Aquaporin-Leitfähigkeiten wurde mit Hilfe von T-DNA-Insertionslinien untersucht. Die verwendeten A. thaliana-Linien atpip1;2-1 und atpip2;3-1, konnten als homozygot charakterisiert werden. Linie atpip1;2-1 enthält lediglich die Insertion im AtPIP1;2-Gen. In Linie atpip2;3-1 findet sich neben der Insertion im AtPIP2;3-Gen eine weitere in einer nicht codierenden Region des 3. Chromosoms. Bei beiden Linien führt die T-DNA-Insertion zum Verlust der entsprechenden Aquaporin-mRNA. Die Untersuchung der hydraulischen Leitfähigkeit von Arabidopsis-Wurzeln der beiden Insertionslinien ergab, dass im Vergleich zur Kontroll-Linie die Abwesenheit von AtPIP2;3 keinen Einfluss auf die hydraulische Leitfähigkeit hat. Dagegen scheint AtPIP1;2 eine Komponente des symplastischen Transportweges von Wasser in der Wurzel zu sein, da atpip1;2-1-Wurzeln eine deutliche Reduktion der hydraulischen Leitfähigkeit aufwiesen. Auch im Blatt konnte eine physiologische Bedeutung von AtPIP1;2 nachgewiesen werden, da Messungen des pflanzlichen Gaswechsels der Linie atpip1;2-1 eine signifikant verringerte photosynthetische Assimilationsrate und stomatäre Leitfähigkeit ergaben. Als Ursache hierfür konnte die starke Reduktion der Mesophyll-Leitfähigkeit für CO2 (gm) identifiziert werden. Hier kommt vermutlich die im heterologen Expressionssystem nachgewiesene molekulare CO2-Leitfähigkeit von AtPIP1;2 zum Tragen. Für Linie atpip2;3-1 konnten bezüglich der Gaswechsel-Analysen keinerlei Unterschiede zu den Kontroll-Pflanzen festgestellt werden. Die Ergebnisse weisen auf eine Funktion von AtPIP1;2 sowohl in der Wasser-Aufnahme durch die Wurzeln als auch in der Erleichterung der CO2-Diffusion im Blatt hin. Hingegen konnte basierend auf den durchgeführten Untersuchungen nicht festgestellt werden, inwieweit AtPIP2;3 von physiologischer Bedeutung ist.
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Heckwolf, Marlies [Verfasser]. "Funktionelle Charakterisierung der Arabidopsis thaliana Aquaporine AtPIP1;2 und AtPIP2;3 / von Marlies Heckwolf." 2010. http://d-nb.info/1000904342/34.
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ROBINSON, Whitney Drummond. "FEEDING HUNGRY PLANTS: THE SECRETED PURPLE ACID PHOSPHATASE ISOZYMES AtPAP12 AND AtPAP26 PLAY A PIVOTAL ROLE IN EXTRACELLULAR PHOSPHATE SCAVENGING IN ARABIDOPSIS THALIANA." Thesis, 2012. http://hdl.handle.net/1974/7394.
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Orthophosphate (Pi) is a limiting macronutrient in most soils and is essential for plant metabolism. Massive amounts of Pi-fertilizers are applied to agricultural fields to compensate for this limitation. However, Pi-fertilizers are made from non-renewable rock Pi-sources and their application is environmentally destructive. Plants have evolved numerous ways to survive in Pi-deficient (-Pi) soils, including the upregulation and secretion of acid phosphatases (APases). APases catalyze the hydrolysis of phosphate (Pi) from Pi-esters in an acidic environment. The major group of plant secreted APases, purple acid phosphatases (PAPs), have been hypothesized to scavenge Pi from organic-Pi (Po) sources that can compose up to 80% of the total P-content of some soils. Previous biochemical and proteomic studies indicate that AtPAP26 and AtPAP12 are the predominant secretory PAP isozymes upregulated by –Pi Arabidopsis thaliana cell cultures and seedlings. This thesis examines the influence of different Po supplements on the growth, Pi content, secretory APase activity, and secreted AtPAP12 and AtPAP26 polypeptides of wildtype (Col-0) Arabidopsis seedlings. Additionally, this thesis assesses the potential role that AtPAP12 and AtPAP26 play in scavenging Pi from extracellular Po sources by utilizing a homozygous atpap12/atpap26 double knockout mutant. Loss of AtPAP26 and AtPAP12 expression resulted in a 64% decrease in root secreted APase activity of –Pi seedlings. These results corroborate previous findings implying that: (i) Arabidopsis are able to grow on a variety of extracellular Po sources as their sole source of P-nutrition, and (ii) AtPAP12 and AtPAP26 are the principal contributors to secreted APase activity of –Pi Arabidopsis. Total shoot Pi levels, and growth of atpap12/atpap26 Arabidopsis seedlings cultivated in -Pi/+Po media were significantly lower relative to Col-0 controls, but unaffected under Pi sufficient conditions. The atpap12/atpap26 seedlings were unable to grow in a –Pi/+Po soil, whereas the Col-0 seedlings were able to develop. Additionally, both PAPs were strongly upregulated on root surfaces and in shoot cell wall extracts of –Pi seedlings. Taken together, these results strongly suggest that AtPAP12 and AtPAP26 play an important role in the hydrolysis of Pi from extracellular Po and make a large contribution to Pi-recycling and scavenging in –Pi Arabidopsis.Thesis (Master, Biology) -- Queen's University, 2012-08-23 11:36:45.722
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Müller, Andreas. "Genetische und molekulare Analyse des AtPIN2-Gens aus Arabidopsis thaliana L. /." 1997. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=008193395&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Su, Hung Chia, and 蘇紅嘉. "E-box regulation of human Atp1a2 promoter." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/24864241454697444679.
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碩士長庚大學
生物醫學研究所
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Circadian rhythm is an approximately 24-hour cycle of our bodily functions including physiology and behavior. In mammals, the circadian rhythm is generated by the central clock located in the hypothalamic suprachiasmatic nuclei (SCN). The SCN neurons exhibit a circadian rhythm in spontaneous firing rate and intracellular Ca2+ concentrations, both being higher during the day than at night. We previously find that the Na+-K+ ATPase (NKA) also has higher daytime activity. The energy-demanding and electrogenic nature of the NKA and its ability to regulate intracellular Na+ and Ca2+ via Na+/Ca2+ exchanger suggest that the NKA may play an important role in the integration of energy metabolism, intracellular ion homeostasis, and neuronal excitability in the SCN. We suspected that the NKA be a clock-controlled gene. Indeed, the rat NKA α2 subunit gene (Atp1a2) has E box (CANNTG) sequence in its promoter region. The aim of this study was to determine the presence of E box in human Atp1a2 promoter and whether the E box may regulate the promoter activity in a clock-controlled manner. We identified E boxes of human Atp1a2 promoter by using promoter deletion assay and determined their activity by using transient transfection assay and luciferase reporter assay in human embryonic kidney 293 (HEK293) cells. Series of Atp1a2 -luciferase clones were constructed by promoter deletion assay. E box mutation clones were further constructed to evaluate which E box is the major regulatory element. And, we constructed stable clones and using luciferase reporter assay to detected whether E boxes of Atp1a2 promoter have circadian rhythm. Transient transfection assay and luciferase reporter assay show that the F2 clone that contains proximal E box has significantly higher luciferase activity than other clones, and F1 clone that contains proximal and distal E boxes has significantly lower luciferase activity than F4 clone which has no E box. E box mutation clones show that as long as distal E box exist, proximal E box can not represent its ability. Stable transfection assay show that stable clone’s luciferase activity trend consistent with transient clone. Our results indicate the distal E box acts as dominant negative regulator and proximal E box acts as positive regulator.
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Tietz, Olaf [Verfasser]. "Funktionelle Charakterisierung des AtPIN1-Proteins aus Arabidopsis thaliana / vorgelegt von Olaf Tietz." 2002. http://d-nb.info/969066104/34.
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Gosch, Jonas. "Epigenetische Suppression von RASAL1 und ATP2A2 als Biomarker und Therapieansatz bei kardialer Fibrogenese." Doctoral thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1412-0.
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Phan, Thi Thanh Hoai. "Investigating the Role of Arabidopsis Plasma Membrane Intrinsic Protein AtPIP2;1 in Seed Germination." Thesis, 2021. https://hdl.handle.net/2440/135687.
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Soil salinity can cause osmotic stress during seed germination by limiting water uptake and causing NaCl accumulation. Exposure to salinity stress during seed imbibition can alter germination percentage, slow the germination rate and seedling growth. Subsets of membrane intrinsic proteins called aquaporins contribute to salinity stress tolerance in plants, and some isoforms of these proteins could have roles in helping seeds to germinate in saline conditions. Aquaporins have multiple roles in many physiological processes, such as solute transport, hydraulic conductance, signalling, development and adjusting to changes in the environment. Recent studies have revealed that some plant aquaporins are candidates for being involved in both water and Na+ transport. For example, Arabidopsis thaliana Plasma Membrane Intrinsic (PIP) proteins AtPIP2;1 and AtPIP2;2 transported both water and univalent cations (Na+ and K+) when tested in heterologous systems. To explore whether AtPIP2;1 influenced Na+ transport in plants, Atpip2;1 loss of function mutants and wild type Columbia-0 seed were germinated on media containing 50 mM NaCl. The wild type Arabidopsis seed appeared to germinate earlier than the seed from the Atpip2;1 mutant lines. This preliminary observation led to the hypothesis that there may be a link between the function of AtPIP2;1 and factors that influence seed germination percentage in Arabidopsis. To test this hypothesis, wild type Arabidopsis, two Atpip2;1 mutant lines, a Atpip2;1*Atpip2;2 mutant line, and two transgenic lines overexpressing AtPIP2;1 (35S::AtPIP2;1) and a null control line were propagated in controlled conditions and seed was harvested from each of these seven genotypes. The seed was used to test whether the seven genotypes differed in germination percentage and seed area, weight and Na+ and K+ content when imbibed in control or saline treatment. This research aims to investigate the role of an aquaporin protein, AtPIP2;1, in seeds in the model plant Arabidopsis thaliana. A series of exploratory experiments were carried to explore possible roles for this protein in seed germination, with a particular focus in germination under salt stress. In saline conditions, seed from Atpip2;1 mutant lines and lines overexpressing AtPIP2;1 germinated slower than wild type and null control lines, respectively. Fifty hours after sowing, the seedlings of one mutant Atpip2;1 line weighed more than wild type, and seedlings of both 35S::AtPIP2;1 overexpression lines weighed less than null controls. When imbibed in saline conditions, Atpip2;1 mutant line seed contained more K+ than wild type seed. Whereas seed from lines overexpressing AtPIP2;1 contained more K+ than null line seed when imbibed for 30 h in water then transferred to a solution containing 75 mM NaCl from 30 to 50 h after sowing, but not when imbibed in the saline treatment from 0 to 50 h. In conclusion, the potential for these observations to be a consequence of AtPIP2;1 transport of water, ions or hormones, or linked to protein-protein interactions and signaling roles are discussed. Options for future experiments targeted at distinguishing which aspects of AtPIP2;1 functions are important in contributing to optimal seed germination in saline treatment are considered.Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2022
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Hütter, Michael [Verfasser]. "Rolle von CACNA1A, ATP1A2 und SCN1A für die sporadische hemiplegische Migräne / vorgelegt von Michael Hütter." 2009. http://d-nb.info/994819579/34.
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Shearer, Monique Kirsten. "Characterisation of AtPQL1, AtPQL2 and AtPQL3 as candidate voltage insensitive non-selective cation channels (vi-NSCCs)." Thesis, 2013. http://hdl.handle.net/2440/83638.
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Soil salinity is responsible for significant reductions in crop yield. The salinity tolerance of crops can be improved by minimising the amount of sodium ions (Na⁺) accumulating in the shoot. One hypothesis for reducing shoot Na⁺ accumulation is to minimise Na⁺ entering the plant via the root. Previous studies indicate that in most plants, the majority of Na⁺ entry into root cells is through voltage-insensitive non-selective cation channels (vi-NSCCs), however, the molecular identities of these channels are unclear. Recently two genes that belong to the PQL family were identified as putative vi-NSCCs in yeast. This project aims to functionally characterise three orthologous PQL genes from Arabidopsis thaliana (AtPQL1, AtPQL2 and AtPQL3) and investigate their role in Na⁺ entry into cells and into roots. Bioinformatic tools and in planta techniques were used to determine gene expression profiles, analyse protein sequences and determine the cellular and subcellular localisations of AtPQL1-3. The plasma membrane localisation of AtPQL1 and 2 agrees with the proposed function of vi-NSCCs as ion transport channels. Furthermore, the suggested role of vi-NSCCs in facilitating initial Na⁺ entry into the roots was supported by in silico expression profiles of AtPQL2 and 3 and by observations of reporter proteins driven by PQL promoters in root tissues. Heterologous expression of AtPQL1 in yeast resulted in yeast which were more salt sensitive than controls, suggesting a role in Na⁺ influx into cells. Furthermore, this sensitivity could be ameliorated by the addition of CaCl₂, (indicating Ca²⁺ inhibited the movement of Na⁺), an attribute which corresponds with known properties of vi-NSCCs. A number of transgenic Arabidopsis lines were generated to have altered expression of AtPQL1 to 3 and were then phenotypically analysed in hydroponics under a range of salt treatments. Results of these experiments proved largely inconclusive primarily because individual plants with significantly altered expression of AtPQL1, 2 and/or 3 could not be obtained.Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2013
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Friml, Jirí [Verfasser]. "Isolation and characterization of novel AtPIN genes from Arabidopsis thaliana L. / by Jirí Friml." 2000. http://d-nb.info/961738510/34.
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Turek, Ilona. "Elucidation of the Signal Transduction Pathways Activated by the Plant Natriuretic Peptide AtPNP-A." Diss., 2014. http://hdl.handle.net/10754/335803.
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Plant natriuretic peptides (PNPs) comprise a novel class of hormones that share some sequence similarity in the active site with their animal analogues that function as regulators of salt and water balance. A PNP present in Arabidopsis thaliana (AtPNP-A) has been assigned a role in abiotic and biotic stress responses, and the recombinant protein has been demonstrated to elicit cyclic guanosine monophosphate (cGMP)-dependent stomatal guard cell opening, regulate ion movements, and induce osmoticum-dependent water uptake. Although the importance of the hormone in maintaining ion and fluid homeostasis has been established, key components of the AtPNP-A-dependent signal transduction pathway remain unknown.
Since identification of the binding partners of AtPNP-A, including its receptor(s), is fundamental to understanding the mode of its action at the molecular level, comprehensive protein-protein interaction studies, involving yeast two-hybrid screening, affinity-based assays, protein cross-linking and co-immunoprecipitation followed by mass spectrometric (MS) analyses have been performed. Several candidate binding partners of AtPNP-A identified with at least two independent methods were subsequently expressed as recombinant proteins, purified, and the specificity of their interactions with the recombinant AtPNP-A was verified using surface plasmon resonance.
Several specific binary interactants of AtPNP-A were subjected to functional assays aimed at unraveling the consequences of the interactions in planta. These experiments have revealed that reactive oxygen species (ROS) are novel secondary messengers involved in the transduction of AtPNP-A signal in suspension-cultured cells of A. thaliana (Col-0).
Further insight into the AtPNP-A dependent signalling events occurring in suspension-cultured cells in ROS-dependent or ROS-independent manner have been obtained from the large-scale proteomics study employing tandem mass tag (TMT) labelling followed by MS analysis to identify and relatively quantify proteins that are differentially expressed upon the treatment with nano- and picomolar concentrations of the biologically active AtPNP-A peptide at different time-points post-treatment.
Characterization of both the AtPNP-A interactome and AtPNP-A dependent proteome afforded novel insights into the signal transduction pathways altered by PNPs and shed new light on the mechanisms by which these candidate interactants operate. Taken together, indications are that PNP dependent mechanisms can be harnessed for possible biotechnological applications.
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Ottenschläger, Iris [Verfasser]. "Gravity regulated differential auxin transport in Arabidopsis roots and the search for interaction partners of AtPIN1 / vorgelegt von Iris Ottenschläger." 2002. http://d-nb.info/964941848/34.
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Del, Vecchio HERNAN. "Biochemical and Molecular characterization of AtPAP25, a novel cell wall-localized purple acid phosphatase isozyme upregulated by phosphate-starved Arabidopsis thaliana." Thesis, 2012. http://hdl.handle.net/1974/7448.
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Upregulation of intracellular and secreted acid phosphatases (APases) is a universal response of orthophosphate-starved (-Pi) plants. APases hydrolize Pi from a broad spectrum of phosphomonoesters at an acidic pH. Plant APases belong to a relatively large multigene family whose specific functions in Pi metabolism are poorly understood. This study focuses on the identification and characterization of cell wall (CW) localized purple acid APases (PAPs) upregulated by -Pi Arabidopsis thaliana. Three glycosylated PAP isozymes secreted into the CW of -Pi Arabidopsis suspension cells were purified and identified by peptide mass fingerprinting using mass spectrometry (MALDI-TOF MS) and N-terminal microsequencing as AtPAP12 (At2g27190; subunit size 60-kDa), AtPAP25 (At4g36350; subunit size 55-kDa) and AtPAP26 (At5g34850; subunit size 55-kDa). Both AtPAP12 and AtPAP26 were previously shown to be upregulated and secreted by –Pi Arabidopsis to scavenge Pi from extracellular organic-P. However, the novel AtPAP25 has never been suggested to be involved in the plant Pi-starvation response. Biochemical characterization of AtPAP25 revealed a monomeric 55 kDa protein. Similar to other PAPs it was purple-in-solution and insensitive to tartrate. Glycoprofiling via LC MS/MS revealed highly complex NXS/T glycosylation motifs at Asn172, Asn367 and Asn424. I hypothesize that these motifs play a role in AtPAP25 targeting and function. Kinetic characterization revealed a broad pH optimum centered at 5.6 and inhibition of activity by several common APase inhibitors. AtPAP25 exhibited broad substrate selectivity, low Vmax, and a Km (phosphoenolpyruvate) value of 0.52 mM. Immunoblot and semi-quantitative RT-PCR transcript analysis indicated that AtPAP25 is exclusively synthesized under –Pi conditions. Deduced amino acid sequences were compared using multiple sequence alignment and phylogenetic analysis. Growth of atpap25 T-DNA insertion mutant knockout seedlings was completely arrested when transferred to a soluble Pi deficient organic-P containing soil mix, pointing to a potential regulatory function of AtPAP25 during nutritional Pi stress. Overall, this research is helping to shed light on the functional importance of specific PAP isozymes in facilitating plant acclimation to nutritional Pi deficiency. This is important because there is an urgent need to engineer Pi-efficient transgenic crops to minimize the huge input of expensive, non-renewable, and polluting Pi fertilizers in agriculture.Thesis (Master, Biology) -- Queen's University, 2012-09-10 08:28:21.631