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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Estudo de genes candidatos aos Transtornos do Espectro Autista / Study of candidate genes to Autism Spectrum Disorders

Ribeiro, Cintia Marques 07 June 2013 (has links)
Os transtornos do espectro autista (TEA) são condições neuropsiquiátricas caracterizadas por padrões comportamentais estereotipados, ausência ou limitação de comunicação verbal e de interação social recíproca. Diversos estudos têm mostrado que esses transtornos possuem etiologia genética complexa e heterogênea, o que dificulta a identificação dos fatores causais. Estima-se que cerca de 70% dos casos de TEA são idiopáticos. Portanto, com o objetivo de identificar mecanismos etiológicos associados aos TEA, utilizamos as seguintes estratégias: customização de uma lâmina de microarray CGH que possibilite a detecção não só de grandes CNVs, mas também de alterações menores do que 10 kbp, em exons e regiões UTR de genes potencialmente candidatos; a comparação entre os tipos de rearranjos detectados em pacientes sindrômicos e em não sindrômicos e, ainda, a investigação mais detalhada de uma família com indivíduos portadores de transtorno autista e síndrome de Asperger. Foram avaliados 103 portadores de TEA não sindrômicos e 18 sindrômicos, sendo as taxas de detecção de alterações potencialmente patogênicas, respectivamente, de 11,6% e 38,9%. Dentre as alterações detectadas 44,4% são menores do que 10 Kbp. Portanto, a estratégia de usar uma lâmina customizada, com alta densidade de sondas complementares aos exons e regiões não codificantes de genes potencialmente envolvidos na etiologia dos TEA, capaz de detectar tanto alterações grandes quanto pequenas, parece ser relevante na tentativa de elucidar o maior número de casos possíveis e melhor compreender esses transtornos. Além disso, essa lâmina também pode ser utilizada como uma ferramenta para auxiliar o diagnóstico clínico e o aconselhamento genético com um custo mais acessível em comparação a outras comerciais ou ao sequenciamento de última geração. Cerca de 33,3% das CNVs observadas afetam região UTR, sugerindo que mutações nessas regiões podem explicar uma proporção significativa dos casos nos quais não são detectadas alterações através de outros testes genômicos, visto que a maioria desses ainda não exploram adequadamente regiões não codificantes. Entre os pacientes autistas não sindrômicos verificou-se que a maioria dos genes afetados por CNVs estão envolvidos em duas principais funções biológicas - sinapses glutamatérgicas e orientação axonal, sugerindo que TEA não sindrômico pode ser causado por disfunção em genes diferentes envolvidos em processos fisiológicos comuns. Diferente do que observamos entre pacientes não sindrômicos, detectamos mais de uma alteração em um mesmo indivíduo ou alterações que englobam mais de um gene entre os pacientes sindrômicos, reforçando o modelo oligogênico para alguns casos de TEA. Por fim, os dados obtidos no estudo da família com portadores de síndrome de Asperger e transtorno autista sugere que a gravidade do quadro clínico possa estar relacionada ao número de mutações e possivelmente por duas mutações diferentes em ambos os alelos de um mesmo gene. Nossos resultados, além de apoiar o envolvimento dos genes MDGA2, FHIT, HTR2A, SHANK2, GRIA3, ZNF778, PRKCα, CDH15, DIAPH3, GCH1, GRM5, MARK1, SLC17A6, IMMP2L, BZRAP1, SYNGAP1, ANK3, MAP1A, GABRR2 e LAMC3 nos TEA também sugere novos genes candidatos: LRRC7, LRRIQ3, CADPS1, NUFIP, SEMA3A, SNAP29, MBD2, GAD2, DGKH e PARD3 / The autism spectrum disorders (ASD) are neuropsychiatric conditions typically characterized by social deficits, communication difficulties, stereotyped or repetitive behaviors and interests. Several studies have shown that these disorders have a complex and heterogeneous genetic etiology, which makes difficult to identify the causal factors. Approximately 70% of cases are idiopathic. In order to identify etiological mechanisms associated with ASD, we have used the following strategies: customized a microarray CGH platform that allows detection not only of large CNVs, but also alterations smaller than 10 kbp in exons and UTR regions of potential candidate genes, the comparison between the types of rearrangements detected in syndromic and non-syndromic patients and further, more detailed investigation of a family segregating both autistic disorder and Asperger syndrome. We evaluated 103 nonsyndromic and 18 syndromic patients by the custom-designed array and the detection rate of possibly pathogenic alterations were, respectively, 11.6% and 38.9%. Among these CNVs, 44.4% are smaller than 10 kbp. Therefore, the strategy of using a custom-designed array, enriched with probes targeted to genes potentially involved in the ASD etiology and able to detect both large and small CNVs, seems to be relevant in an attempt to elucidate the largest number of cases and to better understand these disorders. Furthermore, this platform can also be used as a tool to support the clinical diagnosis and genetic counseling with a more affordable cost compared to conventional other or next-generation sequencing. Approximately 33.3% of the observed CNVs affect UTR region, suggesting that mutations in non-coding regions might explain a significant proportion of ASD cases negative for most genomic screenings, which still do not explore adequately these regions. Among nonsyndromic autistic patients we found that most of the genes affected by CNVs are involved in two main biological functions - glutamatergic synapses and axonal guidance, suggesting that nonsyndromic ASD can be caused by dysfunction in different genes of a few common physiological processes. In contrast to our findings in nonsyndromic patients, we detected more than one alteration in a single individual or alterations that involve more than one gene among the syndromic patients, reinforcing the oligogenic model for some cases of ASD. Finally, the data obtained in the study of the family segregating both Asperger syndrome and autistic disorder suggests that the severity of ASD seems to be modulated by the number of hits and possibly by hits in both alleles of the same gene. Our results support the involvement of genes MDGA2, FHIT, HTR2A, SHANK2, GRIA3, ZNF778, PRKCα, CDH15, DIAPH3, GCH1, GRM5, MARK1, SLC17A6, IMMP2L, BZRAP1, SYNGAP1, ANK3, MAP1A, GABRR2 and LAMC3 in ASD etiology and also suggests new candidates: LRRC7, LRRIQ3, CADPS1, NUFIP, SEMA3A, SNAP29, MBD2, GAD2, DGKH and PARD3
172

O direto de acesso à cultura como escusa legítima para a reprodução não autorizada de obra esgotada

Leone, Elisa Gremen Mimary 13 February 2017 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-02-22T11:43:28Z No. of bitstreams: 1 Elisa Gremen Mimary Leone.pdf: 1258918 bytes, checksum: 42952cd82be41b67b7792f0d0ac6454e (MD5) / Made available in DSpace on 2017-02-22T11:43:28Z (GMT). No. of bitstreams: 1 Elisa Gremen Mimary Leone.pdf: 1258918 bytes, checksum: 42952cd82be41b67b7792f0d0ac6454e (MD5) Previous issue date: 2017-02-13 / The purpose of this work is to study in what circumstances and for what reasons the unauthorized full reproduction of a work which copies are sold out could be legitimately excusable. The justification for this study is the need to find a legal solution to the y y “ k” . w y hy h z that the culture access right, as it is a fundamental right and is provided in the Federal Constitution, could be used as an argument for the relativization of the prohibition. Throughout the paper, a doctrinal survey was made regarding the subject, including foreign doctrine, as a way of verifying the assertiveness of the hypothesis. After the doctrinal research and analysis of the subject, it was concluded that, not only would justification for unauthorized reproduction be based on the culture access right but also that there is a public interest involved in the satisfaction of this right, as well as some legal instruments that can be used in real cases where this relativization is necessary / Este trabalho tem por objetivo estudar em quais circunstâncias e por quais motivos poderia ser legitimamente escusável a reprodução integral não autorizada de uma obra cujos exemplares estejam esgotados. A justificativa que se faz para esse estudo é a necessidade de buscar uma solução jurídica para a impossibilidade de obtenção de um exemplar quando existe uma situação de esgotamento. Foi levantada inicialmente a hipótese de que o direito de acesso à cultura, por ser um direito fundamental de todos e estar previsto na Constituição Federal, poderia ser utilizado como argumento para a relativização da proibição. Ao longo do trabalho foi feito um levantamento doutrinário a respeito do tema, incluindo doutrina estrangeira, como forma de verificar a assertividade da hipótese. Após a pesquisa doutrinária e análise do tema, chegou-se a conclusão de que não só seria possível a justificação da reprodução não autorizada com base no direito de acesso à cultura como também que existe um interesse público envolvido na satisfação desse direito, além de alguns instrumentos jurídicos que poderão ser utilizados nos casos reais em que se faça necessária essa relativização
173

Genetic alterations of the metastatic lesions in ovarian carcinoma / Les altérations génétiques et transcriptomiques des métastases du cancer de l'ovaire.

Malek, Joël 16 December 2011 (has links)
Le cancer de l’ovaire est le cancer gynécologique avec la plus grande mortalité due à un diagnostique tardif au stade de maladie extensive péritonéale. Malgré les progrès de la chirurgie radicale et de la chimiothérapie les récurrences abdominales demeurent la cause la plus fréquente de mortalité. Il existe peu d’études de la maladie métastatique péritonéale. Notre hypothèse de travail est que les différences entre la maladie métastatique et la tumeur primaire sont primordiales dans la survenue d’une maladie résiduelle ou récurrente. Nous avons utilisé une approche exhaustive comprenant des études du transcriptome, des variations du nombre de copie (VNC) et des sequençages des exomes pour caractériser les différences entre lésions primaires, métastases péritonéales et métastases lymphatiques.Résultats: Notre étude démontre que les VNC varient de façon significative entre la tumeur primaire et la métastase peritonéale. Les différences d’expressions géniques bien que mineures permettent de retrouver les voies de signalisation primordiales pour le développement des métastases. Le séquençage des exomes montre très peu de différences en terme de polymorphisme. Par ailleurs la majorité des polymorphismes présents dans les métastases se retrouvent à une faible fréquence dans la tumeur primaire de façon concordante avec la théorie clonale. Conclusion: L’ensemble des résultats montre la possibilité d’une origine clonale de la maladie métastatique des cancers de l’ovaire comportant la majorité des anomalies au niveau des variations du nombre de copie. L’intégration de ces données permettrait d’optimiser les thérapeutiques ciblées. / Ovarian cancer is the most deadly gynecological cancer. The high rate of mortality is due to the large tumor burden with extensive metastatic lesion of the abdominal cavity. There are few studies on genetic alterations and their consequences in peritoneal metastatic tumors when compared to their matched ovarian primary tumors. Our hypothesis is that differences between the metastatic and primary lesions might be the cause of residual disease and, most importantly may have a role in post-chemotherapeutic recurrences. Methods: We conducted integrated genomics analysis on matched primary and metastatic tumors from 9 patients. In the papers presented here we analyze genome-wide Copy Number Variations (CNVs) using SNP Arrays targeting peritoneal metastasis differences, Gene expression differences using Microarrays also targeting peritoneal metastasis differences, and for some patients, Single Nucleotide Polymorphisms (SNPs) in genes through Exome sequencing.Results: Here we show that CNVs vary significantly between primary and metastatic tumors and include genes that have been considered potential chemotherapeutic targets based on primary tumor only data. Gene expression differences, while minor, showed highly statistically significant enrichment of genes in ovarian cancer critical pathways. In agreement with findings in other cancers, exome sequencing data revealed very few SNP differences of which most metastasis enriched SNPs were present at very low levels in the primary tumor. The results presented here should allow better design of therapies to target residual ovarian cancer disease.
174

Transformação genética de cana de açúcar e validação de genes de referência para avaliação de número de cópias inseridas por PCR em tempo real / Genetic transformation of sugarcane and validation of reference genes for evaluation of the number of copies inserted by real-time PCR

Batista, Tânia Regina 22 August 2016 (has links)
Atualmente a procura por produtos sustentáveis têm-se mostrado cada vez mais frequente e promissora. Em espécies de importância comercial, procura-se obter a maior produtividade possível dentro de um curto espaço de tempo aliado à preservação do meio ambiente. Dentro disso, a transformação genética de plantas se mostra uma alternativa atrativa para a geração de variedades de cana-de-açúcar que gerem produtos de maneira mais eficaz. O sucesso da transformação genética está diretamente associada a cultura de tecidos de plantas que precisa ser adequada a cada genótipo e situação de cultivo, sendo a luminosidade um dos principais fatores para a produção de plantas vigorosas. Outro fator importante é a seleção das plantas transgênicas, que precisam ser submetidas a uma quantidade de agente seletivo suficiente para identificar as plantas modificadas geneticamente. Em cana-de-açúcar, a identificação de plantas transgênicas por PCR e a definição do número de cópias é um procedimento de difícil execução e muito oneroso. Isto se dá pois no processo transformação via biolística, a inserção de genes é aleatória, produzindo plantas com variados números de cópias. Em consideração a estes fatores envolvidos na eficiência de obtenção de plantas transgênicas de cana-de-açúcar, os objetivos deste trabalho foram o aperfeiçoamento do protocolo de cultura de tecidos, transformação genética da variedade SP803280 com os genes xth, AtDdm1, como também, definir genes de referência para a quantificação do número de cópias dos genes xth e AtDdm1 inseridos na variedade SP803280 e do gene neo na RB835089, análise de ploidia e tamanho de genoma dos eventos transgênicos comparado com as plantas controle. No estudo a respeito da melhor qualidade de luz durante o cultivo in vitro na fase de regeneração de plantas, tem-se que a luz branca e a junção das luzes LED e branca se mostraram melhores para regeneração e desenvolvimento das plantas enquanto que para plântulas, as luzes LED e branca separadamente foram mais efetivas no crescimento. Para a seleção das plantas uma concentração de geneticina entre 40 e 50 mgL-1 é recomendada. As taxas de sucesso nas transformações genéticas para o gene xth variaram entre 2,5 a 18,3% dependendo do experimento e para AtDdm1 foi de 2,2% em um bombardeamento.Não houveram alterações de ploidia e tamanho do genoma nos transgênicos das duas variedades em relação à planta selvagem. Os genes p4h e prr foram identificados como os melhores para a quantificação relativa de genes inseridos por PCR em tempo real na variedade SP803280 enquanto que para a RB835089 aprt e prr se mostraram mais eficazes. A análise do número de cópias inseridas em eventos transgênicos por PCR em tempo real foi possível através das duas metodologias de cálculo testados por este trabalho, com resultados que concordam com uma tendência nesta determinação de maneira simples e rápida. / Currently the demand for sustainable products has been shown to be frequent and promising. In species of commercial importance, there is an effort to obtain the highest possible productivity in a short time, along with the environment preservation. In this context, genetic transformation of plants appears as an attractive alternative for the development of sugarcane varieties able to generate products in a more effective way. The genetic transformation success is directly associated to plant tissue culture that requires specific condition for each genotype and cultivation process, in which, luminosity is one of the main factors that determines the production of vigorous plants. Another important factor is the selection of transgenic plants, that occur by exposing plants to a sufficient amount of selective agent in order to identify only genetic modified plants. In sugarcane, identification of transgenic plants by PCR and the definition of copy numbers is a difficult procedure to implement and usually is very costly. It is because in the process of genetic transformation by biolistic, the insertion of genes occurs randomly and also produce plants with varied copy numbers. In consideration of these factors directly involved in the efficiency to obtain sugarcane transgenic plants the objectives of this study were the improvement of a tissue culture protocol, the genetic transformation of the variety SP803280 with xth and AtDdm1 genes. Also, the studies include the definition of reference genes for determining the number of copies inserted of xth and AtDdm1 genes into the variety SP803280 and neo gene in RB835089, ploidy analysis and genome size of the transgenic events compared to control plants. In the study related to the best light quality for in vitro plant regeneration, white light and the combination of LED and white lights proved to be better for plants regeneration and development while for seedlings, LED and white light separately were more effective for growth. In order to obtain selection of transgenic plants, geneticin concentration between 40 and 50 mg L-1 is recommended. Success rates in xth genetic transformation ranged from 2.5 to 18.3% depending on the experiment, and for AtDdm1 was only 2.2% in just one biolistic bombardment. There were no changes in ploidy and genome size in transgenic events related to their wild type plant. The genes p4h and prr were defined to be the best for determining the copy number of transgenic events by real time PCR in SP803280 variety, while for RB835089, the genes aprt and prr were the most effective. The analysis of the number of inserted copies was possible using the two calculation methodologies tested by this work, with results that agree with a tendency in a simple and fast quantification methodology.
175

Hur spelar jag det jag hör? : Observationsstudie i hur man plankar eller transkriberar musik / How do I play what I hear? : An observational study in how to copy or transcribe music

Gumar, Guran January 2018 (has links)
Syftet med det här arbetet är att upptäcka metoder och strategier för att på gehör planka musik. Genom studier har jag undersökt min lärandeprocess när jag plankar en rocklåt på gehör. Jag har fört loggbok och ljudupptagningarunder arbetsprocessen för att kunna dokumentera vad som har hänt och få vetskap om hur jag har gått tillväga. I bakgrunden har jag använt mig av det sociokulturella perspektivet som teori och denna teori har varit grunden till analysen av min lärandeprocess. Jag har då upptäckt vad jag använder för olika kulturella redskap när jag plankar och hur dessa används i min process. Dessa redskap presenteras i resultatdelen som röst och memorering, tidiga musikstudier, strukturlyssning och begränsning samt foten. Detta innebar att jag behövde memorera det jag hörde noggrant för att sedan kunna applicera det på mitt instrument. Rösten representerades som sång vilket innebär att jag sjöng det som hade memorerats och förtydligade för fingrarna vad som skulle spelas. För att kunna gå vidare och övervinna de svåra delarna i arbetet behövde jag begränsa mig till små delmål i låten och strukturera mitt arbetssätt. Mina tidiga studier och erfarenheter i musiken var grunden till att jag överhuvudtaget kunde börja plankningsprocessen och att utvecklas i den. Foten hjälpte mig att känna pulsen och förtydligade taktslaget för att kunna behålla det rätta notvärdet. I diskussionen jämför jag resultatet med tidigare forskning och litteratur som berör ämnena gehör, plankning och strategier för plankning. Jag avslutar arbetet med mina egna reflektioner kring arbetets betydelse och möjliga fortsatta studier. / The purpose of this study is to discover methods and strategies about how to transcribe[1]music by ear. Through studies, I have observed my learning process when I transcribe a rock song by ear. I have used a logbook and sound recordings during the work process to document what has happened and get knowledge of how I have been doing. In the background, I have used the sociocultural perspective as theory and this theory has been the basis for the analysis of my learning process. I have then discovered what I use for different cultural tools as I transcribe music and how these are used in my process. These tools are presented in the result section as voice and memorization, early music studies, limitation and structure listening as well as the foot as a tool. This means that I needed to memorize what I heard carefully to then apply it to my instrument. The voice was represented as song, for example, I sang what had been memorized and clarified for the fingers what would be played. In order to move on and overcome the difficult parts of the work, I had to limit myself to small sub-goals in the song and structure my way of working. My early studies and experiences in music were the reason why I could in general start the transcribing process and develop in it. The foot helped me feel the pulse and clarify the beat to keep the correct note value. In the discussion, I compare the result with previous research and literature related to topics hearing, transcribing and strategies for transcribing. I finish the work with my own reflections about the importance of work and possible further studies.
176

Contribution différentielle des variations du nombre de copies aux troubles du spectre autistique et aux traits cognitifs.

Zeribi, Abderrahim 01 1900 (has links)
No description available.
177

Mucolytic Bacteria And The Mucosal Barrier In Inflammatory Bowel Diseases

Chin Wen Png Unknown Date (has links)
The intestinal mucosa is made up of complex secreted mucus layer consist of mainly mucin 2 (MUC2) and antimicrobial components that defend the underlining cellular barrier from intrusion by luminal microbiota and toxins. In inflammatory bowel diseases (IBD), the mucosal integrity is compromised. This can result from a combination of altered host genetics, gut immune responses and environment factors. However, it is the presence of intestinal bacteria that is central to the pathogenesis of IBD. As part of the dynamic gut microbial flora, mucolytic bacteria produce a wide range of glycosidases that are able to remove the outer oligosaccharide chains of MUC2, which allow other luminal bacteria to further degrade the mucin. We hypothesised that increased mucolytic bacteria will cause excessive degradation of the mucus layer, which in turn, allow more luminal bacteria to be in close proximity to the underlining epithelial cells resulting in inflammation. Consistent with our group’s previous semi-quantitative bacterial 16S rRNA gene clone library analysis, we found increased Ruminococcus gnavus in non-inflamed ulcerative colitis (UC) mucosa. R. gnavus was previously isolated by others based on its mucolytic property. In this study, we quantify total mucosa-associated bacteria and mucolytic bacteria, namely, R. gnavus, R. torques, Akkermansia muciniphila and bifidobacteria. We were able to show quantitatively that total mucosa-associated bacteria were increased in IBD. There was also a population shift in the mucosa-associated mucolytic bacteria, which were increased overall. There was significantly more R. gnavus in non-inflamed IBD biopsies. For the first time, we were also able to demonstrate that R. gnavus can degrade human MUC2 in vitro. To examine whether the numerical association of R. gnavus in IBD does have functional influence on intestinal inflammation and Paneth cell antimicrobial peptide gene expression, we fed mice with R. gnavus. Interestingly, R. gnavus feeding did not result in histological or molecular evidence of gut inflammation; however, it was able to specifically induce Paneth cell cryptdins and lysozyme P genes expression in 3 week old, antibiotic pre-treated C57BL/6 mice. This demonstrated that R. gnavus is not a pathogenic bacterium, which will directly cause colitis. However, the increased Paneth cell response suggested the need for host innate defence when R. gnavus is increased. Other than bacterial degradation, altered host genetics will also influence the mucus barrier. There is evidence to suggest that the MUC2 gene is highly unstable and is susceptible to gene copy number variation (CNV). Therefore, we hypothesised that MUC2 CNV is present, which may result in altered oligomerisation of the MUC2 glycoprotein causing endoplasmic reticulum stress of the goblet cells that appears to be characteristic of UC. Currently, our data partly support the presence of MUC2 CNV. However, further investigation is required to verify the MUC2 CNV identity. Only then can a high throughput methodology be designed to screen a large population for any association with IBD.
178

Array-based Genomic and Epigenomic Studies in Healthy Individuals and Endocrine Tumours

Sandgren, Johanna January 2010 (has links)
The human genome is a dynamic structure, recently recognized to present with significant large-scale structural variation. DNA-copy number changes represent one common type of such variation and is found both between individuals and within the somatic cells of the same individual, especially in disease states like cancer.  Apart from DNA-rearrangements, epigenomic changes are increasingly acknowledged as important events in the maintenance of genomic integrity. In this thesis, different array-based methods have been applied for global genomic and epigenomic profiling of both normal and cancer cells. In paper I, a genomic microarray was established and used to determine DNA-copy number variants (CNVs) in a cohort of 76 healthy individuals from three ethnic populations. We identified 315 CNV regions that in total encompassed ~3,5% of the genome. In paper II, the array was utilized to discover CNVs within several differentiated tissues from the same subject. Six variants were identified providing evidence for somatic mosaicism. In paper III and IV we studied pheochromocytomas and paragangliomas, rare endocrine tumours that most often present as benign and sporadic with unclear genetic/epigenetic cause. Genome-wide DNA-copy number analysis of 53 benign and malignant samples in paper III revealed numerous common and novel chromosomal regions of losses and gains. High frequencies of relatively small overlapping regions of deletions were detected on chromosome 1p arm, encompassing several candidate tumour suppressor genes. In paper IV, an epigenomic map for two histone modifications associated with silent (H3K27me3) or active (H3K4me3) gene transcription, was generated for one malignant pheochromocytoma. Integrated analysis of global histone methylation, copy number alterations and gene expression data aided in the identification of candidate tumour genes. In conclusion, the performed studies have contributed to gain knowledge of CNVs in healthy individuals, and identified regions and genes which are likely associated with the development and progression of pheochromocytoma/paraganglioma.
179

Evidence for a Dynamic Adaptor Complex between the P1 Plasmid and Bacterial Nucleoid Promoted by ParA and ParB Partition Proteins

Havey, James C. 21 August 2012 (has links)
P1 prophage is stably maintained in E. coli as a low-copy-number plasmid. Stable maintenance of P1 is dependent on the function of the plasmid encoded partition system, parABS. ParA is the partition ATPase, ParB is the partition-site binding protein, and parS is the partition site. The concerted action of these proteins results in dynamic movement of the plasmid over the bacterial nucleoid, which results in its stable maintenance. Plasmid movement has been proposed to be caused by interactions between parS bound ParB and nucleoid bound ParA. In this thesis, I have identified a complex of ParA, ParB, and DNA that is capable of promoting plasmid stability. ParA, ParB, DNA interactions required the ATP bound conformation of ParA. The ParA-ParB-DNA complex was dynamically regulated by nucleotide hydrolysis, which promoted complex disassembly. Complex formation resulted from the cooperative binding of ParA and ParB to DNA. ParA-ParB and ParB-DNA interactions were both necessary for complex formation. ParA-ParB-DNA complex size was regulated by ParB stimulation of ParA-ATP hydrolysis. Microscopy demonstrated that complexes resulted in the association of multiple DNA molecules due to protein binding. The properties of complex assembly, dynamics, and DNA grouping lead me to propose a model where associations between ParA bound to the bacterial nucleoid and the partition complex mediated plasmid movement and localization.
180

"Advertorials" : a genre-based analysis of an emerging hybridized genre / Genre-based analysis of an emerging hybridized genre

Zhou, Si Jing January 2007 (has links)
University of Macau / Faculty of Social Sciences and Humanities / Department of English

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