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Solórzano, Navarro Eduvigis. "De la Mesoamérica Prehispánica a la Colonial: La huella del DNA antiguo." Doctoral thesis, Universitat Autònoma de Barcelona, 2006. http://hdl.handle.net/10803/3682.
Full textAbstract:
Este trabajo es una contribución al estudio de la diversidad genética en las poblaciones americanas antiguas. Se ha analizado el DNA procedente de restos humanos esqueléticos de yacimientos mesoamericanos de tres épocas distintas, con dataciones que se ubican desde la época azteca prehispánica (post-clásico tardío) a la colonia del Virreinato de la Nueva España, con la finalidad de inferir, desde la visión de los linajes maternos, la dinámica de las poblaciones del Valle Central de México y el posible aporte genético del contingente español y africano que llegó a tierras americanas, específicamente a México, desde finales del siglo XVI. Se estudiaron los marcadores del DNA mitocondrial (mtDNA) a partir de restricción enzimática de fragmentos en la región codificante y de la secuenciación de un segmento de la región hipervariable I. Los distintos análisis se realizaron observando un estricto control de los criterios de autenticidad en relación a las condiciones de laboratorio, el uso de controles, la caracterización de los investigadores, diversidad genética, sentido filogenético y total correspondencia entre los marcadores mitocondriales, concordancia que es reconocida como un criterio de autenticidad cuando se analiza el mtDNA proveniente de restos antiguos.
De los ciento dos individuos estudiados, ochenta y siete fueron clasificados entre los cuatro principales haplogrupos descritos para nativos americanos (A, B, C y D) y tres no segregaron para ninguno de estos haplogrupos, ni siquiera para el quinto y menos frecuente linaje americano, el haplogrupo X; a la luz de los datos de que se dispone hasta el momento es probable de que se trate de individuos cuyo linaje maternal pertenezca a alguno de los haplogrupos africanos (L1, L2 y L3), siendo la primera evidencia genética del aporte africano en época colonial. En los doce individuos restantes no se lograron amplificaciones positivas para más de un sitio de restricción, por lo cual fueron excluidos de la investigación.
Los análisis de comparación entre las tres series antiguas permiten deducir una continuidad entre los linajes mitocondriales anteriores al contacto europeo y los linajes de la época colonial, no observándose diferencias significativas entre ellas. Sin embargo, la presencia de secuencias únicas en la serie de contacto permite hipotetizar un colapso poblacional en algunos núcleos indígenas. Los resultados obtenidos tanto a nivel de haplogrupos como de secuencias también han sido comparados con datos de poblaciones actuales y antiguas de América y Asia obtenidos de la literatura; y de esta manera, situar en el contexto poblacional americano las muestras antiguas del Valle Central mexicano.
Los procedimientos de reconstrucción filogenética nos permiten deducir que las series antiguas del Valle Central de México tienen un vínculo por vía matrilineal con el resto de las poblaciones americanas, y especialmente con la población mexicana contemporánea de referencia. Además, está virtualmente ausente el aporte europeo en las muestras analizadas, debido posiblemente, a que el proceso de mestizaje que se produjo durante los siglos XVI y XIX fue de tipo unidireccional, hombre europeo-mujer indígena y el mtDNA sólo nos permite el análisis del aporte genético materno.
This paper is a contribution to the genetic diversity study in ancient American populations. DNA from Mesoamerican human skeletal remains from three different periods, which cover from the pre-Hispanic Aztec epoch (late post-classical) to the Viceroyalty of New Spain at the colonial period were analyzed, with the purpose to infer, with the information that the maternal lineages can provide us, Mexico's Central Valley population dynamics; and the possible genetic contribution of the Spanish and African contingents that arrived to the Americas, specifically to Mexico, since the last period of the XVIth century.
Mitochondrial DNA (mtDNA) markers have been studied by both specific restriction enzyme analysis in the coding region and by sequencing of the hypervariable region I segment. The analyses were carried out with a strict control of the authenticity criteria, focusing on: laboratory conditions, use of blank controls, mtDNA characterization of laboratory researchers, genetic diversity, phylogenetic sense and total correspondence among mitochondrial markers, which is recognized as an authenticity criterium where mtDNA analysis from ancient remains is concerned.
Of the hundred two individuals studied, eighty-seven were classified among the four major founding mtDNA haplogroups described for American natives (A, B, C, and D), three individuals didn't segregate for any of these haplogroups, not even for the fifth and less frequent American founding lineage, the haplogroup X; and it is probable that their maternal lineage belong to one of the African haplogroups (L1, L2 or L3), being the first genetic evidence of the African contribution in the colonial epoch. Finally, in twelve individuals positive amplifications were achieved in no more than one restriction site, reason by which they were excluded of the investigation.
The analysis comparison among the three ancient series showed that there is continuity between mitochondrial lineages previous to the European contact and colonial lineages, and that there is not a significant difference among them. Nevertheless, the presence of exclusive lineages in contact series allows us to hypothesize a population collapse in some native groups. The results obtained using both methods of the mtDNA analysis have also been compared with ancient and current populations data from America and Asia available in the literature; and in this way, we have been able to place in the American context the Mexico's Central Valley samples.
Phylogenetic reconstruction procedures permit to deduce that Mexico's Central Valley ancient series have a maternal link with the remaining American populations, and especially with the Mexican current population of reference. In addition the European contribution in the samples analyzed is virtually absent possibly owing to that the mestizaje process that was produced during the XVIth and XIXth centuries was of one-directional: European man - Native woman and mtDNA only permits maternal genetic analysis.
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Montiel, Duarte Rafael. "Estudio diacrónico de la variabilidad del DNA mitocondrial en población catalana." Doctoral thesis, Universitat Autònoma de Barcelona, 2001. http://hdl.handle.net/10803/3641.
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El DNA mitocondrial (mtDNA) es útil para estudios de genética de poblaciones humanas debido a que su genoma está completamente caracterizado, es de herencia materna y tiene una tasa de evolución relativamente rápida. Las técnicas de DNA antiguo, que empezaron a desarrollarse en 1984, han añadido una variable temporal a este tipo de estudios a pesar de que existe cierta desconfianza debido al riesgo de contaminación de las muestras con DNA moderno. Por otra parte, el estudio de la población Catalana resulta interesante debido a que el análisis de componentes principales de marcadores clásicos mostró su diferenciación respecto a otras poblaciones ibéricas; diferenciación que fue corroborada por estudios de comparación de secuencias de mtDNA.Bajo estas consideraciones fue planteado como objetivo principal valorar las posibilidades que tienen los estudios de DNA antiguo a nivel poblacional, en la resolución de problemas como la estimación de la tasa de evolución y el origen del acervo genético mitocondrial europeo y el desarrollo de métodos fiables para la detección de la contaminación con DNA exógeno. Con este fin se analizó la población Catalana de dos épocas diferenciadas.
Para el estudio de la población antigua se analizaron 52 individuos de la necrópolis de la Plaça Vella de Terrassa, Barcelona (s. XV-XVI) y se obtuvo mtDNA de 24 de ellos. En este análisis también se incluyeron diversos individuos de distintos yacimientos a manera de control metodológico. Para el análisis de la población contemporánea se caracterizó el mtDNA de 90 individuos de población residente de las ciudades de Terrassa y Barcelona y estudiantes de la Universidad Autónoma de Barcelona.
En los 24 individuos de la Plaça Vella se encontraron 12 secuencias diferentes con un índice de diversidad que cae dentro del rango obtenido para otras poblaciones europeas. En estos individuos están representados 7 de los 9 haplogrupos europeos y la distribución que presentan también es similar a la que presentan la mayoría de poblaciones europeas. Estas observaciones junto con distintos criterios discutidos en esta tesis avalan la autenticidad de los resultados obtenidos.
Con estos datos se realizó un análisis filogenético incluyendo información previamente publicada de 11 series poblacionales principalmente europeas. El análisis mostró una cercana relación entre las poblaciones antigua y actual de Cataluña y evidenció también la cercanía entre estas poblaciones y otras poblaciones mediterráneas en cuanto a su mtDNA. En cambio, la relación de la población Catalana con otras poblaciones ibéricas (Galicia y País Vasco) no resultó tan estrecha.
Paralelamente a los estudios de las poblaciones antigua y actual, se llevó a cabo una investigación sobre las substancias que presentan los extractos de DNA antiguo que tienen un poder inhibitorio en las reacciones enzimáticas. El análisis comparativo apoya la hipótesis de que estas substancias sean alguna fracción de los ácidos húmicos, descartando las porfirinas, el daño del DNA y los iones libres de hierro. La hipótesis de que sean productos Maillard no fue rechazada pero no se obtuvo evidencia en favor de ella. Además, se encontró un método sencillo que disminuye los efectos negativos que presentan estas substancias durante la Reacción en Cadena de la Polimerasa (PCR).
Mitochondrial DNA (mtDNA) is useful in population genetics studies because its genome is fully characterised, it is maternally inherited and it shows a fast evolution rate. Ancient DNA techniques, beginning in1984, have added a temporal variable to this kind of studies although there is some controversy around this kind of analysis, due to contamination problems with modern DNA. The study of the Catalonian population is interesting since previous reports have shown some differentiation of this population from other Iberian populations, by means of principal components analysis for classic markers. This differentiation has been corroborated in some studies by comparing mtDNA sequences.
Under these considerations, the main objective of the present work was to assess the ability of ancient DNA studies - at population level - to solve problems such as the evolution rate estimation, the origin of the mitochondrial gene pool in Europe, and the development of reliable methods to detect exogenous DNA contamination. For this purpose, Catalonian populations from two different periods were analysed.
For the ancient population, 52 individuals from the necropolis of PlaçaVella, Terrassa, Barcelona (XV-XVI centuries) were analysed. Mitochondrial DNA was recovered from 24 individuals. As a methodological control, several individuals from different sites were included in this study. For the contemporary population, the mtDNA from 90 contemporary individuals inhabitants of Terrassa and Barcelona cities and students from the Universitat Autònoma de Barcelona was analysed.
There were 12 different sequences in the 24 individuals from the PlaçaVella, which showed an index of diversity fitting in the range observed for other European populations. These 24 individuals presented 7 out of the 9 European haplogroups and their distribution looked like most of the European populations. These observations, along with another criteria discussed in this work, support the authenticity of the results.
The data obtained from the ancient population as well as from the contemporary population, were used in a phylogenetic analysis, including previously published information from 11 population series, mainly European. This analysis showed a close relationship between the ancient and contemporary populations from Catalonia, as well as between these populations and other Mediterranean populations, regarding its mtDNA. On the other hand, the relationship between Catalonian population and other Iberian populations (Galicia and Basque Country) was not so close.
Besides the studies on ancient and contemporary populations, a research on the inhibitory substances usually found in ancient DNA extracts was carried out. The comparative analysis supports the hypothesis that these substances are a humic acid fraction, discarding another substances as the putative inhibitors. The possibility that these substances are Maillard reaction products was not rejected; however, there was no evidence supporting this possibility. In this work, a novel and simple method to overcome the PCR inhibition produced by these substances was uncovered.
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Galimany, Skupham Jacqueline Lorna. "Patrones de parentesco y residencia mediante DNA antiguo en el uso mortuorio de la cueva Estero Sur, Archipiélago de los Chonos." Tesis, Universidad de Chile, 2015. http://repositorio.uchile.cl/handle/2250/136512.
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Antropóloga FísicaEl grupo canoero más septentrional del archipiélago patagónico occidental y el primero en extinguirse es conocido etnohistóricamente como Chono. Lo que sabemos de su organización social se basa en observaciones no sistemáticas de la etnia post-contacto y las características y alteración de los contextos mortuorios de cuevas y aleros rocosos solo permiten un mero vistazo a lo que fue este grupo. La reciente validación de la unidad genética de los antiguos habitantes del Archipiélago de los Chonos nos permite plantear nuevas interrogantes. El sitio mortuorio cueva Estero Sur constituye el osario más antiguo (~2000 AP) y numeroso hallado en la zona. La mínima divergencia de sus fechados lo define como un contexto ideal en la búsqueda de patrones de parentesco y residencia. Para ello, se caracterizó los haplotipos de DNA mitocondrial y cromosoma Y de los individuos de la cueva Estero Sur y una muestra control de fechados cercanos hallada en contextos mortuorios de cueva del Archipiélago de los Chonos. La frecuencia, diversidad y distancia genética de los linajes presentes en los individuos de ambos conjuntos indican un patrón probablemente aleatorio de uso mortuorio del sitio, descartando su uso exclusivo por parte de una familia nuclear, un matrilinaje o un patrilinaje. Este patrón concuerda con una depositación mortuoria dispersa, consecuencia de una alta y amplia movilidad
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Fehren-Schmitz, Lars, Bastien Llamas, Elsa Tomasto, and Wolfgang Haak. "Ancient DNA and the Early Population History of Western South America: What Have We Learned So Far and Where Do We Go From Here." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/113534.
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Even though the analysis of DNA from archaeological bone comes with some major limitations, it constitutes the most directmeans of investigating prehistoric population dynamics. The interdisciplinary contextualization of genetic data with the archaeological and palaeoecological record helps to reconstruct past population histories and the demography of ancient populations. For South America, palaeogenetic studies have become increasingly important. Here we review the existing ancient DNA data from pre-Columbian individuals to assess their potential to contribute to our understanding of early South American population history. The spatial and temporal distribution of ancient South American populations analysed to date is very uneven and the data resolution of the analysed genetic markers is low. Nevertheless, the data suggest that there were population dynamic processes accompanying cultural development in Western South America. With the new methodologies and better sampling strategies employed in current paleogenetic projects and more effective interdisciplinary cooperations it will be soon possible to achieve a better understanding of the peopling of the continent and the succeeding population history.Aún cuando el análisis de ADN de huesos arqueológicos tiene algunas grandes limitaciones, constituye la manera más directa de investigar eventos prehistóricos de dinámica poblacional. La contextualización interdisciplinaria de los datos genéticos con los registros arqueológico y paleoecológico permite reconstruir las historias poblacionales pasadas y la demografía de sociedades antiguas. Por otro lado, el número de estudios paleogenéticos en Sudamérica se está incrementando. En este artículo revisamos los datos de ADN antiguo de individuos prehispánicos que existen en la actualidad con la finalidad de evaluar su potencial para contribuir a nuestro entendimiento de la historia temprana del poblamiento de Sudamérica. La distribución espacial y temporal de las poblaciones sudamericanas antiguas muestreadas a la fecha es muy irregular y la resolución de los marcadores genéticos analizados esbaja. Sin embargo, los datos sugieren que existieron procesos de dinámica poblacional que acompañaron el desarrollo cultural de la parte oeste de Sudamérica. Con las nuevas metodologías y mejores estrategias de muestreo que se emplean hoy en día en los proyectos de paleogenética, y con una cooperación interdisciplinaria más efectiva, pronto será posible lograr un mejor entendimiento del poblamiento del continente, así como de los hechos sucesivos de su historia poblacional.
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Fehren-Schmitz, Lars. "Pre-Columbian Population Dynamics and Cultural Development in South Coast Perú as Revealed by Analysis of Ancient DNA." Pontificia Universidad Católica del Perú, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/113298.
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In this paper I report on a study whose principal aim is to understand the development and decline of the southern Peruvian Nasca culture in the upper Río Grande de Nasca drainage, and its cultural and biological affinities to the preceding Paracas culture. Ancient DNA analyses were conducted on over 300 pre-Columbian individuals from various cemeteries in southern Perú, from periods ranging from the Formative Period to the Middle Horizon. Our results show that the Nasca populations are close related to those of the preceding Paracas culture, and combined with archaeological data, suggest that the Nasca culture was autochthonous to the Río Grande drainage. Furthermore, one can observe how changes in socioeconomic complexity influence the genetic diversity. The pre-Columbian coastal populations of southern Perú differ significantly from both ancient highland and all present-day Peruvian populations. The genetic differentiation between the main cultural areas of western South America seems to fade with the Middle Horizon.Se presenta aquí un estudio cuyo objetivo principal es la comprensión del desarrollo y decadencia de la cultura Nasca en la parte alta de la cuenca del Río Grande de Nasca, así como sus afinidades biológicas y culturales con su antecesora, la cultura Paracas. Se realizaron análisis de ADN antiguo en más de 300 individuos procedentes de varios cementerios prehispánicos del sur del Perú correspondientes a un lapso que se inicia en el Período Formativo y alcanza el Horizonte Medio. Los resultados muestran que las poblaciones nasca son cercanas a las de su cultura precedente. Esta información, combinada con los datos arqueológicos, sugiere que la cultura Nasca se desarrolló, de manera autóctona, en la cuenca del Río Grande. Más aún, se puede observar que los cambios socioeconómicos de este período influyeron en la diversidad genética. Las poblaciones prehispánicas costeñas del sur del Perú difieren, significativamente, de las antiguas poblaciones de la sierra y de las poblaciones peruanas actuales. La diferenciación genética entre las principales áreas culturales de la parte oeste de Sudamérica parece desaparecer en el Horizonte Medio.
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Ferrando-Bernal, Manuel 1990. "Analysis of co-ancestry links in modern and ancient human populations." Doctoral thesis, TDX (Tesis Doctorals en Xarxa), 2021. http://hdl.handle.net/10803/672475.
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The aim of this thesis is to apply Identity by Descent (IBD) methodology to identify ancestry connections among individuals from genetically similar populations. Recombination events diminish the likelihood to detect IBDs. As most of the aDNA samples date from 2,000 years ago or more, this methodology has rarely been applied to these studies. In this thesis we detect IBD among modern individuals from similar Bantu populations and among modern Europeans with an historical individual (700 years ago) from the Iberian peninsula, which was sequenced to a high coverage. Our results show that IBDs can be used to detect the genomic structure in genetically close populations. For example, they can be used to show high degrees of endogamy caused by isolation or to identify ancestral connections among individuals belonging to different populations that otherwise would be difficult to see with other more commonly used methods.
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Sampietro, Bergua Mª Lourdes. "Genetic Analysis of the prehistoic peopling of Western Europe: Ancient DNA the role of contamination." Doctoral thesis, Universitat Pompeu Fabra, 2007. http://hdl.handle.net/10803/79128.
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In this thesis we have addressed three different although related topics. First, we studied the post-mortem mutation damage rate of contaminated DNA sequences in ancient human remains focusing on the development of strategies to avoid pre-laboratory derived contaminations. We proposed a guideline to control them consisting in typing every single person involved on the manipulation of the remains, especially when they have not been excavated and washed under controlled conditions. Second, we successfully develop a non-invasive technique to sequence ancient remains but preserving it from the destruction. And third, we sequenced ancient human remains from different evolutionary times (from Paleolithic to post-Neolithic) to make inferences about the peopling of Western Europe focusing mainly in the Iberia peninsula. We found that there is a long term genetic continuity at least since the Neolithic. The only clear genetic discontinuity found is that involving two different human species, H. sapiens and H. neanderthalensis.En la presente tesis hemos tratado tres temas diferentes aunque muy relacionados. Primero, hemos estudiado la tasa de mutación post-mortem de secuencias de ADN contaminante en restos humanos antiguos centrándonos en el desarrollo de estrategias para evitar que las muestras se contaminen antes de llegar al laboratorio. Proponemos una guía que consiste en el tipado genético de cada persona implicada en la manipulación de los restos, especialmente cuando estos han sido excavados y lavados bajo condiciones no controladas. Segundo, hemos desarrollado una técnica no invasiva para secuenciar DNA de restos humanos antiguos pero sin destruirlos. Y por ultimo, hemos secuenciado restos humanos antiguos pertenecientes a diferentes periodos evolutivos (desde el Paleolitico hasta el post-Neolitico) que nos han permitido hacer inferencias sobre el poblamiento Europeo centrándonos básicamente en la Península Ibérica. Hemos encontrado que ha habido una continuidad genética desde el Neolítico. La única clara discontinuidad genética encontrada es entre dos especies distintas: H. Sapiens y H.neanderthalensis.
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Song, Keli 1955. "DNA-based vaccination against carcinoembryonic antigen." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36837.
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DNA vaccination is based on in vivo delivery of plasmids encoding an antigen, leading to antigen synthesis and specific immunity. This technology is still in its infancy but has advantages over conventional vaccination, such as the stimulation of all arms of the immune response, i.e., humoral immunity, T-helper (17h) cells and cytotoxic T lymphocytes (CTLs). We studied DNA vaccination against human carcinoembryonic antigen (CEA) in mice. Our hypothesis was that codelivery of cytokine- and CEA-encoding plasmids could regulate responses, and allow polarization of Th responses to either type 1 (Th1) or type 2 (Th2). We found that intramuscular injection of the CEA plasmid alone induced antibodies, Th1 cells and CTLs reactive to CEA. These mice had increased immunity against transplanted syngeneic CEA+ stably transfected tumor cell lines, but always developed lethal tumors. Coinjection of the CEA plasmid with a vector encoding either IL-12 or interferon gamma (IFNgamma) markedly enhanced IgG2a production (IFNgamma-dependent), IFNgamma secretion by spleen cells (a Th1 cytokine) and CTL-mediated tumor cell lysis, in a CEA-specific way. Moreover, resistance to a tumor challenge was greatly improved, such that up to 80% of mice survived tumor free. In contrast, coinjection of CEA and IL-4 genes increased CEA-specific IgG1 levels (IL-4-dependent) and IL-4 secretion by lymphocytes (a Th2 cytokine), but decreased both CTL activity and tumor resistance. Thus, we could readily enhance or polarize immunity. The IL-12 cDNA had the strongest adjuvant effect, which was only observed when it was injected at the same site as the CEA gene. To analyze effector components, we studied IL-12-plasmid-enhanced DNA vaccination in gene knockout mice, lacking either CD3, CD4, CD8. IFNgamma, perforin or Fas ligand (FasL). Only mice expressing all of CD3, CD4, IFNgamma, CD8 and perforin, and inoculated with both the CEA and IL-12 genes, could fully resist a tumor challenge. The Fas/FasL lytic
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López, de Rioja Víctor. "Population range expansions, with mathematical applications to interacting systems and ancient human genetics." Doctoral thesis, Universitat de Girona, 2019. http://hdl.handle.net/10803/667171.
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The thesis studies from an analytical and computational perspective, and by using reaction-diffusion equations, the spatiotemporal evolution of different populations.
First, the dynamics of the T7 bacteriophage infecting the E. coli bacteria is studied. By adding the delayed time in diffusion and reaction terms, as well as new mathematical terms biologically sound, we can achieve results that accurately match the experimental propagation speeds.
Secondly, different mathematical models are proposed to correctly understand the expansion of VSV in Glioblastoma. The only model capable of this explanation is the system which understands the delay time for the processes of diffusion and reaction.
Finally, the Neolithic transition through Europe is explained by studying ancient genetic DNA samples alongside mathematical simulations. Focusing on haplogroup K, the model is built by analyzing the two Neolithic diffusion mechanisms: demic and cultural. The simulations show that the transition is basically demic, with only 2% of the Neolithic farmers interacting culturallyAquesta tesi estudia des d’un punt de analític i computacional, gràcies a les equacions de reacció-difusió, l’evolució espaciotemporal de diferents poblacions que interactuen entre elles. El primer article estudia la dinàmica del bacteriòfag T7 infectant el bacteri E. coli. Gràcies a la incorporació del temps de retard en els termes de difusió i reacció, així com de nous termes matemàtics amb sentit biològic, aconseguim uns resultats que s’ajusten millor a les velocitats de propagació. El segon article aplica diferents models matemàtics per entendre millor l’expansió del VSV en Glioblastomes. L'únic model capaç d'explicar de manera correcte el sistema té en compte el temps de retard per als processos de difusió i reacció. L’últim article explica la transició del Neolític a través d’Europa utilitzant mostres genètiques antigues i simulacions matemàtiques. Centrant-nos en l’haplogrup K, el model es construeix tenint en compte els dos mecanismes de difusió neolítica: dèmica i cultural. Les simulacions mostren que la transició és bàsicament dèmica, on només el 2% dels neolítics interaccionen culturalment
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Ola, Ayodele Oluronke. "A functional analysis of proliferating cell nuclear antigen (PCNA)." Thesis, King's College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391441.
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Gigli, Elena. "Evolutionary genetics of homo neanderthalensis :adaptive traits and methodological problems." Doctoral thesis, Universitat Pompeu Fabra, 2011. http://hdl.handle.net/10803/77656.
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The evolutionary history of H. neanderthalensis, interwoven with that of H. sapiens, has always fascinated the scientific world. Recent adavncess in paleogenetics shedds new light on the phylogenetic relationship between Neandertals and modern humans. The studies developed in this thesis intend principally to control the contaminants through the development of an anti-contamination protocol for decreasing the human contamination in pre-laboratory phases. We designed a PCR-based method specific for reducing human contamination during the laboratory analysis, and we analyzed the fragmentation pattern of the ancient sequences by massively parallel sequencing technologies. Furthermore, we studied two nuclear genes, TAS2R38 -associated to bitter taste perception- and ABO blood group system –involved in natural immunity- that provide specific information on aspects of the Neanderthal phenotype and adaptation.La historia evolutiva d’H. neanderthalensis, imbricada amb la d’H. sapiens, ha fascinat sempre el món científic. Avenços recents en paleogenètica aporten una nova llum sobre la rel•lació filogenètica entre els neandertals i els humans moderns. Els treballs d’aquesta tesi intenten principalment controlar els contaminants mitjançant el desenvolupament d’un protocol d’anti-contaminació que disminueixi la contaminació humana de les mostres en la fase de pre-laboratori. Hem desenvolupat un mètode basat en la PCR específic per a reduïr els contaminants humans durant l’anàlisi en el laboratori, i hem analitzat el patró de fragmentació de les seqüències antigues amb tècniques de seqüenciació massiva en paral•lel. A més a més, hem estudiat dos gens nuclears, el TAS2R38 –associat a la percepció del gust amarg- i el grup sanguini ABO –implicat en la immunitat natural- que proporcionen informació específca sobre aspectes del fenotip i de les adaptacions dels neandertals.
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Simanis, V. "T antigen binding sequences in cellular DNA." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37854.
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Sunstrom, Noëlle-Ann. "Specific DNA binding by polyomavirus large T antigen." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70257.
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To define the DNA binding domain of polyomavirus large T antigen, systematic deletion mutagenesis was carried out on large T antigen. A set of plasmids coding for unidirectional carboxy- or amino-terminal deletion mutations in large T antigen were constructed. Deleted proteins were expressed by plasmid transfection of Cos-1 cells. Analysis of origin-specific DNA binding by mutant proteins revealed that the C-terminal boundary of the DNA-binding domain is at or near Glu 398. Fusion proteins of large T antigen lacking the first 200 N-terminal amino acids bound specifically to polyomavirus origin DNA; however, deletions beyond this site resulted in unstable proteins which could not be tested for DNA binding. Testing of point mutants and internal deletions by others suggest that the N-terminal boundary of the DNA-binding domain lies between amino acids 282 and 286. Taken together, these results locate the DNA-binding domain of polyomavirus large T antigen to the 116- amino acid region between residues 282 and 398.Polyomavirus large T antigen binds to four discrete regions within the regulatory region of the viral genome. The relative arrangement of these binding sites may be important for the distinct regulatory functions performed by the protein. Each of the four large T antigen binding sites was separately cloned into a test plasmid by the use of oligonucleotide-directed mutagenesis. The binding affinity of large T antigen was analyzed for each individual site and for combinations of sites. The results of this analysis showed that there exists an hierarchy of binding strength among individual and combinations of large T antigen binding sites as measured by DNA immunoprecipitation. In addition, the DNA binding of large T antigen involves cooperative interaction of protein molecules between adjacent binding sites, and the integrity of the amino terminus is required for cooperativity.
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Maurer, Tobias. "CpG-DNA-antigen conjugates a new class of therapeutics? /." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=974416622.
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Tanha, Jamshid. "Preparation and analysis of anti-DNA antigen binding fragments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq23885.pdf.
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Ruiz, Elena. "DNA fusion vaccines against HPV16 E7 antigen-associated cancers." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/374745/.
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To date, the success of cancer vaccines in human clinical trials has been limited. One of the reasons for this is the immunological tolerance to tumour antigens found in cancer patients. A novel DNA fusion vaccine design which links a pathogen-derived domain (DOM) of fragment C from tetanus toxin to a peptide epitope from a tumour antigen has been developed in our laboratory. The microbial sequence is able to activate a non-tolerised pool of helper T cells, providing T-cell help for immune induction against the linked tumour-specific sequence. The main aim of this project was to produce a therapeutic DNA vaccine against human papillomavirus (HPV)-associated cancers. A number of DNA fusion vaccines against the E7 antigen from HPV16 were constructed, including pDOM.E749-57, which encodes a well described H-2Db-binding epitope from E7 fused to the DOM sequence. CD8+ T-cell responses to the vaccines were demonstrated using flow cytometry and functional assays. Importantly, these responses were stronger than those induced by a published synthetic long peptide strategy. In vivo tumour challenge experiments showed that DNA vaccines had a protective and therapeutic effect. The vaccines were then tested in transgenic mice which develop spontaneous E7-expressing tumours in a setting of tolerance. DNA vaccine-mediated E7-specific CD8 + T-cell responses were successfully induced in these mice, together with a reduction in the mass of spontaneous tumours. This is the first demonstration of pDOM-epitope DNA vaccine-mediated therapy for spontaneous tumours and bodes well for translation into the clinic. One limiting factor for DNA vaccination in humans may be the delivery system. Electroporation (EP) is one approach which may overcome this. Therefore, a secondary aim of this project was to investigate the impact of EP on immune responses to DNA vaccination in more detail. EP proved essential for generating T-cell and antibody responses to the pDOM.E7 49-57 vaccine in sub-optimal conditions. This information will be crucial for the planning of therapeutic vaccination protocols in patients.
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Rytkönen, A. (Anna). "The role of human replicative DNA polymerases in DNA repair and replication." Doctoral thesis, University of Oulu, 2006. http://urn.fi/urn:isbn:9514281381.
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Abstract
The maintenance of integrity of the genome is essential for a cell. DNA repair and faithful DNA replication ensure the stability of the genome. DNA polymerases (pols) are the enzymes that synthesise DNA, a process important both in DNA replication and repair. In DNA replication DNA polymerases duplicate the genome during S phase prior to cell division. Pols α, δ, and ε are implicated in chromosomal DNA replication, but their exact function in replication is not yet completely clear. The mechanisms of different repair pathways and proteins involved are not yet completely characterised either. The deeper understanding of DNA repair and replication mechanisms is crucial for our understanding on the function of the cell.
The mechanism of repair of DNA double strand breaks (DSBs) by non-homologous end joining (NHEJ) was studied with an in vitro assay. DNA polymerase activity was found to be involved in NHEJ and important in stabilising DNA ends. Antibodies against pol α, but not pol β or ε, decreased NHEJ significantly, which indicates the involvement of pol α in NHEJ. In addition, the removal of proliferating cell nuclear antigen (PCNA) slightly decreased NHEJ activity.
The division of labour between pols α, δ, and ε during DNA replication was studied. Results from UV-crosslinking, chromatin association, replication in isolated nuclei, and immunoelectron microscopy (IEM) studies showed that there are temporal differences between the activities and localisations of the pols during S phase. Pol α was active throughout S phase, pol ε was more active at early S phase, whereas the activity of pol δ increased as S phase advanced. These results suggest that pols δ and ε function independently during DNA replication.
Pol ε could be crosslinked to nascent RNA, and this labelling was not linked to DNA replication, but rather to transcription. Immunoprecipitation studies indicated that pol ε, but not pols α and δ, associated with RNA polymerase II (RNA pol II). Only the hyperphosphorylated, transcriptionally active RNA pol II was found to associate with pol ε. A large proportion of pol ε and RNA pol II colocalised in cells as determined with immunoelectron microscopy. The interaction between pol ε and RNA pol II suggests that they are involved in a global regulation of transcription and DNA replication.
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Guo, Shuangli. "Role of DNA replication proteina (RPA) and proliferating cell nuclear antigen (PCNA) in human DNA mismatch repair." Lexington, Ky. : [University of Kentucky Libraries], 2005. http://lib.uky.edu/ETD/ukybioc2005d00284/etd.pdf.
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Thesis (Ph. D.)--University of Kentucky, 2005.Title from document title page (viewed on November 7, 2005). Document formatted into pages; contains x, 3 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 84-92).
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Dorin, Julia Ruth. "Isolation and characterization of the cDNA for cystic fibrosis antigen." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/13693.
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Fernández, Domínguez Eva. "Polimorfismos de DNA mitocondrial en poblaciones antiguas de la cuenca mediterránea." Doctoral thesis, Universitat de Barcelona, 2005. http://hdl.handle.net/10803/795.
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Los orígenes de las poblaciones europeas han sido abordados desde diversas disciplinas, destacando la contribución de los estudios de genética de poblaciones. Se barajan dos momentos en la prehistoria en los que se ha podido modelar el acervo genético de las poblaciones europeas: la difusión del neolítico y las expansiones del paleolítico superior. La posibilidad de recuperar información genética de poblaciones pretéritas ofrece una oportunidad única para comprobar in situ las hipótesis planteadas desde otras disciplinas.
Se estudiaron 197 muestras dentales y óseas de 115 individuos de 17 yacimientos arqueológicos de época neolítica y sumeria de Próximo Oriente, época meroítica de Nubia y de época paleolítica, neolítica y post-neolítica de la Península Ibérica. Se obtuvieron secuencias completas de DNA mitocondrial de 244 p.b. de 35 individuos distintos, que fueron comparadas con secuencias de la misma región de individuos actuales de 38 poblaciones europeas, africanas y de Próximo Oriente.
En las reconstrucciones filogenéticas basadas en la distancia de Reynolds los grupos de muestras antiguas se agrupan entre sí, separándose del resto de poblaciones actuales. Sin embargo, las reconstrucciones filogenéticas realizadas a partir de los haplotipos de las muestras antiguas y modernas denotan que, aunque la mayoría de variantes mitocondriales antiguas no están presentes en las poblaciones actuales muestreadas, pueden relacionarse más o menos cercanamente con ellas.
La composición de haplotipos y haplogrupos de las muestras antiguas de Próximo Oriente y la Península Ibérica difiere notablemente de la hallada en las poblaciones actuales de estas regiones geográficas.
En la muestra antigua de Próximo Oriente destaca especialmente la ausencia de los haplogrupos mitocondriales J, U3, W y X, relacionados con la expansión del neolítico hacia Europa. Esto puede deberse bien a que la muestra antigua obtenida no es representativa -cronológica o geográficamente- de las poblaciones de Próximo Oriente que se expandieron durante el neolítico bien a que estas variantes no fueron introducidas en europa durante el neolítico.
En la muestra antigua de la Península Ibérica destaca la presencia de un 50% de líneas subsaharianas. Estas líneas pudieron haber sido introducidas durante el Solutrense, el Mesolítico o el Neolítico.
En este trabajo también se profundizó en diferentes aspectos técnicos relativos a la obtención de auténtico DNA antiguo y en la influencia de diversas variables en la preservación del material genético.
The origins of the European populations have been extensively studied from different disciplines. It is thought that ancient demic expansions, like those occurred after the Late Glacial Maximum or during the neolithic diffussion from Middle East to Europe.
The possibility to recover DNA from past populations offers an unique opportunity to test in situ these hypothesis.
It were analyzed 197 teeth and bones from 115 individuals and 17 different archaeological sites from Middle East and the Iberian Peninsula .
It was possible to recover 244pb-mitochondrial DNA sequences from 35 different individuals. They were compared to sequences from 38 European, African and Middle Eastern present-day populations.
Phylogenetic reconstructions from Reynolds genetic distance showed that ancient samples clustered together, clearly separated from extant populations. However, phylogenetic reconstructions based on ancient and modern haplotypes showed that ancient mitochondrial haplotypes are related to extant ones.
Haplotype and haplogroup frequencies in the ancient samples from Middle East and the Iberian Peninsula are clearly different from those present nowadays in the same geographical regions.
Haplogroups related to neolithic expansion to Europe -J, U3, W and X- are absent in ancient middle eastern sample. There are two possible explanations to this fact. First, it could be possible that the ancient samples analyzed won't be representative of the Middle Eastern populations that expanded the neolithic. Second, it could be also possible that those haplogroups won't have been introduzed in Europe with demic expansions associated to neolithic.
At this work it were also examined several technical aspects related to the obtention of genuine ancient DNA and the influence of different variables in DNA preservation.
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Middleton, Jennifer Elizabeth. "An Anti-Tumour DNA Vaccine Targeting the Endothelial Antigen Tie-2." Thesis, University of Nottingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519418.
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Vittes, Gisella E. "Developing DNA Vaccines against the Cancer-Related Prostate-Specific Membrane Antigen." Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509466.
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Nicholson, Philippa Ruth. "The roles of Shc, PPZA and Hsc 70 binding in transformation by polyoma middle-T antigen." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252110.
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Paul, Solomon Devakumar Lovely Jael. "Effective mismatch repair depends on timely control of PCNA retention on DNA by the Elg1 complex." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=239915.
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Proliferating cell nuclear antigen (PCNA) is a sliding clamp that acts as a central co-ordinator for mismatch repair as well as DNA replication. Loss of Elg1, the major subunit of the PCNA unloader complex, causes over-accumulation of PCNA on DNA and also increases mutation rate, but it has been unclear if the two effects are linked. In this study, I showed that timely control of PCNA retention on DNA by Elg1 replication factor C-like complex (Elg1-RLC) ensures correct mismatch repair. Although premature unloading of PCNA generally increases mutation rate, PCNA mutants PCNA-R14E and PCNA-D150E that spontaneously fall off DNA attenuate the mutator phenotype of elg1Δ. In contrast, PCNA-D21K that accumulates on DNA due to enhanced electrostatic PCNA-DNA interactions exacerbates the elg1Δ mutator phenotype. Next, I addressed how accumulation of PCNA on DNA increases mutation rate. Epistasis analysis suggests that PCNA over-accumulation on DNA predominantly prevents the Msh2-Msh6-dependent and Exo1-independent mismatch repair pathways. In elg1Δ, over-retained PCNA hyper-recruits the Msh2-Msh6 mismatch recognition complex through its PCNA-interacting peptide motif, causing accumulation of mismatch repair intermediates. The results suggest that PCNA retention controlled by the Elg1-RLC is critical for efficient mismatch repair: PCNA needs to be on DNA long enough to enable mismatch repair, but if it is retained too long it interferes with downstream repair steps.
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Tokonzaba, Etienne. "Molecular mechanism of SV40 large tumor antigen helicase /." Connect to abstract via ProQuest. Full text is not available online, 2007.
Find full textAbstract:
Thesis (Ph.D. in Pharmacology) -- University of Colorado Denver, 2007.Typescript. Includes bibliographical references (leaves 82-92; 128-134). Online version available via ProQuest Digital Dissertations.
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Roos, Anna-Karin. "Delivery of DNA vaccines against cancer /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-895-9/.
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Yoon, Rosa. "Merkel Cell Polyomavirus Small T Antigen Perturbs the Cellular DNA Damage Response." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17463129.
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Merkel cell polyomavirus (MCPyV) small T antigen (ST) is expressed in the majority of Merkel cell carcinomas (MCC), a highly lethal and aggressive cancer of the skin. Since the discovery of MCPyV in 2008, the role of ST in the context of the virus and MCC has been under intense investigation. Much of our knowledge of polyomavirus ST comes from research on other polyomaviruses, including mouse polyomavirus (MPyV) and simian virus 40 (SV40). Both MPyV and SV40 ST contribute to transformation in part by binding to and inhibiting the cellular phosphatase PP2A. Likewise, MCPyV ST interacts with PP2A, although mutants that are reported to abolish this interaction still transform cells, suggesting that MCPyV ST has PP2A-independent functions. Understanding the unique cellular perturbations induced by MCPyV ST will thus be important for understanding the tumorigenesis of MCC.
In this dissertation, we sought to understand the manipulation of cellular functions by MCPyV ST. We began by characterizing the MCPyV ST protein itself, starting with structural and functional comparisons with other well characterized polyomaviruses and identifying the interaction of MCPyV ST with cellular proteins. We observed that MCPyV ST uniquely interacts with the TIP60 cellular complex, which contains an ATPase and an acetyltransferase and is involved in histone modifications and DNA damage repair. Through predictions of the structure, we identified a surface-exposed region of ST, loop 4, and observed that regions in this loop were important for regulating the binding of ST to the TIP60 complex.
Functionally, we investigated the role of MCPyV ST in the DNA damage response because of its interaction with TIP60 and because DNA damaging agents are used to treat MCCs. In addition, overcoming checkpoint regulation in the p53 pathway is an open question in MCPyV infection. We determined that ST increased sensitivity to DNA damage by γ-irradiation and etoposide and that expression of ST caused persistence of double strand DNA breaks (DSB) after damage, suggesting that DSB repair was delayed in ST expressing cells. Specifically, we observed that ST expression inhibits repair of breaks by nonhomologous end joining (NHEJ) but does not inhibit repair by homologous recombination (HR). These effects on the DNA damage response are explained in part by a less robust phosphorylation of DNA-PKcs at serine residue 2056, which is important for regulating end processing and repair by NHEJ. Taken together, these results indicate that MCPyV ST disrupts the cellular DNA damage response, which has implications on the viral life cycle and the initiation and treatment of MCC.Medical Sciences
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Ito, Kosei. "c-Jun stimulates origin-dependent DNA unwinding by polyomavirus large T antigen." Kyoto University, 1997. http://hdl.handle.net/2433/202211.
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Yap, Jonathan Woon Teck. "Dendritic cell maturation and activation via RNA/DNA danger signals : co-delivery of protein antigen with siRNA or CpG DNA." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/38449.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Biological Engineering Division, 2005."June 2005."
Includes bibliographical references (p. 40-43).
Traditional vaccines consisting of live attenuated pathogens or inactivated toxins cannot be readily applied to the more challenging diseases of the present e.g. hepatitis C and the human immunodeficiency virus. As such, there is a need to develop new methods of priming the immune system against such foreign invaders. Recombinant protein subunits and peptides are relatively safe alternatives to live attenuated pathogens. However, these antigens are poorly immunogenic when administered alone in solution form and thus require the use of an adjuvant. To this end, we have developed a hydrogel-based nanoparticulate system to encapsulate protein antigen and to co-deliver it with DNA/RNA-based adjuvants to dendritic cells, the key antigen presenting cells in primary immune responses. Using CpG oligonucleotides or siRNA as adjuvants, we observed via enzyme-linked immunosorbent assays for interleukin 12 and interferon-[alpha], respectively, that DCs were activated by CpG oligonucleotide- and siRNA-functionalized nanoparticles [approx.]10-fold more potently than by soluble CpG or siRNA ligands.
by Jonathan Woon Teck Yap.
M.Eng.
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Manna, David. "Mutational analysis of the central channel in the Simian virus 40 large T antigen helicase." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.82 Mb., 110 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1435876.
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Freudenthal, Bret D. "Studies of proliferating cell nuclear antigen and its role in translesion synthesis." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/668.
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One major pathway to overcome DNA damage induced replication blocks is translesion DNA synthesis, which is the replicative bypass of DNA damage by non-classical polymerases. For the cell to utilize translesion synthesis the non-classical DNA polymerase is recruited to sites of DNA damage, and a polymerase switch occurs between the stalled classical polymerase and the incoming non-classical polymerase. This process requires the replication accessory factor proliferating cell nuclear antigen (PCNA) and its monoubiquitination at Lys-164.
To better understand the role of PCNA during translesion synthesis, I biochemically and structural characterized two PCNA mutant proteins, G178S and E113G PCNA, which are defective in translesion synthesis. The X-ray crystal structure of both mutant proteins showed a shift in an extended loop, called loop J, compared to the wild type PCNA structure. Steady state kinetic studies determined that in contrast to wild type PCNA which stimulates the non-classical polymerases, the two PCNA mutant proteins fail to stimulate the activity of the non-classical polymerase pol η. These results indicate that loop J in PCNA plays an essential role in facilitating translesion synthesis.
During the structural studies of the E113G PCNA mutant protein I observed a unique PCNA structure that failed to form the characteristic PCNA ring shape structure, through traditional intersubunit interactions of domain A and domain B on neighboring subunits. Instead this non-trimeric PCNA structure formed A-A and B-B intersubunit interactions. The B-B interface is structurally similar to the A-B interface observed for the trimeric ring shaped form. In contrast the A-A interface is stabilized by hydrophobic interactions. The location of the E113G substitution is directly within this hydrophobic surface and would not be favorable in the wild type protein. This suggests that the side chain of Glu-113 promotes trimer formation by destabilizing these possible alternate subunit interactions.
To biochemically and structurally characterize the impact of monoubiquitinating PCNA (Ub-PCNA), I developed an Ub-PCNA analog by splitting the protein into two self-assembling polypeptides. This analog supports cell growth and translesion synthesis in vivo, and steady state kinetic studies showed that the Ub-PCNA analog stimulates the catalytic activity of pol η in vitro. The X-ray crystal structure of Ub-PCNA showed that the ubiquitin moieties are located on the back face of PCNA. Surprisingly, the attachment of ubiquitin does not change PCNA's conformation. This implies that PCNA ubiquitination does not cause an allosteric change to PCNA, and instead facilitates non-classical polymerase recruitment to the back of PCNA by forming a new binding surface for the non-classical polymerases.
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Klaue, Daniel. "DNA Unwinding by Helicases Investigated on the Single Molecule Level." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-97596.
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Each organism has to maintain the integrity of its genetic code, which is stored in its DNA. This is achieved by strongly controlled and regulated cellular processes such as DNA replication, -repair and -recombination. An essential element of these processes is the unwinding of the duplex strands of the DNA helix. This biochemical reaction is catalyzed by helicases that use the energy of nucleoside triphophate (NTP) hydrolysis. Although all helicases comprise highly conserved domains in their amino acid sequence, they exhibit large variations regarding for example their structure, their function and their target nucleic acid structures. The main objective of this thesis is to obtain insight into the DNA unwinding mechanisms of three helicases from two different organisms. These helicase vary in their structures and are involved in different pathways of DNA metabolism. In particular the replicative, hexameric helicase Large Tumor-Antigen (T-Antigen) from Simian virus 40 and the DNA repair helicases RecQ2 and RecQ3 from Arabidopsis thaliana are studied. To observe DNA unwinding by these helicases in real-time on the single molecule level, a biophysical technique, called magnetic tweezers, was applied. This technique allows to stretch single DNA molecules attached to magnetic particles. Simultaneously one can measure the DNA end-to-end distance. Special DNA hairpin templates allowed to characterize different parameters of the DNA unwinding reaction such as the unwinding velocity, the length of unwound DNA (processivity) or the influence of forces. From this mechanistic models about the functions of the helicases could be obtained. T-Antigen is found to be one of the slowest and most processive helicases known so far. In contrast to prokaryotic helicases, the unwinding velocity of T-Antigen shows a weak dependence on the applied force. Since current physical models for the unwinding velocity fail to describe the data an alternative model is developed. The investigated RecQ helicases are found to unwind and close short stretches of DNA in a repetitive fashion. This activity is shown for the first time under external forces. The experiments revealed that the repetitive DNA unwinding is based on the ability of both enzymes to switch from one single DNA strand to the other. Although RecQ2 and RecQ3 perform repetitive DNA unwinding, both enzymes differ largely in the measured DNA unwinding properties. Most importantly, while RecQ2 is a classical helicase that unwinds DNA, RecQ3 mostly rewinds DNA duplexes. These different properties may reflect different specific tasks of the helicases during DNA repair processes. To obtain high spatial resolution in DNA unwinding experiments, the experimental methods were optimized. An improved and more stable magnetic tweezers setup with sub-nanometer resolution was built. Additionally, different methods to prepare various DNA templates for helicase experiments were developed. Furthermore, the torsional stability of magnetic particles within an external field was investigated. The results led to selection rules for DNA-microsphere constructs that allow high resolution measurementsJeder Organismus ist bestrebt, die genetischen Informationen intakt zu halten, die in seiner DNA gespeichert sind. Dies wird durch präzise gesteuerte zelluläre Prozesse wie DNA-Replikation, -Reparatur und -Rekombination verwirklicht. Ein wesentlicher Schritt ist dabei das Entwinden von DNA-Doppelsträngen zu Einzelsträngen. Diese chemische Reaktion wird von Helikasen durch die Hydrolyse von Nukleosidtriphosphaten katalysiert. Obwohl bei allen Helikasen bestimmte Aminosäuresequenzen hoch konserviert sind, können sie sich in Eigenschaften wie Struktur, Funktion oder DNA Substratspezifität stark unterscheiden. Gegenstand der vorliegenden Arbeit ist es, die Entwindungsmechanismen von drei verschieden Helikasen aus zwei unterschiedlichen Organismen zu untersuchen, die sich in ihrer Struktur sowie ihrer Funktion unterscheiden. Es handelt sich dabei um die replikative, hexamerische Helikase Large Tumor-Antigen (T-Antigen) vom Simian-Virus 40 und die DNA-Reparatur-Helikasen RecQ2 und RecQ3 der Pflanze Arabidopsis thaliana. Um DNA-Entwindung in Echtzeit zu untersuchen, wird eine biophysikalische Einzelmolekültechnik, die \"Magnetische Pinzette\", verwendet. Mit dieser Technik kann man ein DNA-Molekül, das an ein magnetisches Partikel gebunden ist, strecken und gleichzeitig dessen Gesamtlänge messen. Mit speziellen DNA-Konstrukten kann man so bestimmte Eigenschaften der Helikasen bei der DNA-Entwindung, wie z.B. Geschwindigkeit, Länge der entwundenen DNA (Prozessivität) oder den Einfluß von Kraft, ermitteln. Es wird gezeigt, dass T-Antigen eine der langsamsten und prozessivsten Helikasen ist. Im Gegensatz zu prokaryotischen Helikasen ist die Entwindungsgeschwindigkeit von T-Antigen kaum kraftabhängig. Aktuelle Modelle sagen dieses Verhalten nicht vorraus, weshalb ein alternatives Modell entwickelt wird. Die untersuchten RecQ-Helikasen zeigen ein Entwindungsverhalten bei dem permanent kurze Abschnitte von DNA entwunden und wieder zusammengeführt werden. Dieses Verhalten wird hier zum ersten Mal unter dem Einfluß externer Kräfte gemessen. Es wird gezeigt, dass die permanente Entwindung auf die Fähigkeit beider Helikasen, von einem einzelen DNA-Strang auf den anderen zu wechseln, zurückzuführen ist. Obwohl RecQ2 und RecQ3 beide das Verhalten des permanenten Entwindens aufzeigen, unterscheiden sie sich stark in anderen Eigenschaften. Der gravierendste Unterschied ist, dass RecQ2 wie eine klassische Helikase die DNA entwindet, während RecQ3 eher bestrebt ist, die DNA-Einzelstränge wieder zusammenzuführen. Die unterschiedlichen Eigenschaften könnten die verschieden Aufgaben beider Helikasen während DNA-Reparaturprozessen widerspiegeln. Weiterhin werden die experimentellen Methoden optimiert, um möglichst hohe Auflösungen der Daten zu erreichen. Dazu zählen der Aufbau einer verbesserten und stabileren \"Magnetischen Pinzette\" mit sub-nanometer Auflösung und die Entwicklung neuer Methoden, um DNA Konstrukte herzustellen. Außerdem wird die Torsions\\-steifigkeit von magnetischen Partikeln in externen magnetischen Feldern untersucht. Dabei finden sich Auswahlkriterien für DNA-gebundene magnetische Partikel, durch die eine hohe Auflösung erreicht wird
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Pavlenko, Maxim. "Induction of T-cell responses against PSA by plasmid DNA immunization /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-385-X/.
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Jiao, Junfang. "Initiation of Simian virus 40 (SV40) DNA replication roles of large T antigen and a newly identified preinitiation complex /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 3.02Mb, 178 p, 2005. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3181870.
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Isoz, Isabelle. "Role of yeast DNA polymerase epsilon during DNA replication." Doctoral thesis, Umeå : Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1932.
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Wang, Weiping. "SV40 large T antigen helicase roles of the hydrophilic channels and a newly identified unwinding activity /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 152 p, 2009. http://proquest.umi.com/pqdweb?did=1833646471&sid=7&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Guo, Shuangli. "ROLE OF REPLICATION PROTEIN A (RPA) AND PROLIFERATING CELL NUCLEAR ANTIGEN (PCNA) IN DNA MISMATCH REPAIR." UKnowledge, 2005. http://uknowledge.uky.edu/gradschool_diss/258.
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PCNA and RPA are required for DNA mismatch repair (MMR), but their rolesin the pathway are not fully understood. Using an affinity pull-down approach, weshow that (1) increased PCNA binding to DNA heteroduplexes is associated withthe appearance and accumulation of excision products; and (2) RPAphosphorylation occurs when DNA polymerase ?? binds to the DNA substrate. Wetherefore hypothesize that PCNA plays an important role in mismatch-provokedexcision and that RPA phosphorylation plays an important role in DNA resynthesis.To determine the role of PCNA in MMR, mismatch-provoked and nick-directedexcision was assayed in a cell-free system in the presence of the PCNA inhibitor,p21CIP1/WAF. We show that whereas PCNA is essential for 3' directed excision, it isdispensable for the 5' directed reaction, suggesting a differential role for PCNA inMMR. We further find that the PCNA-dependent pathway is the only pathway for3' directed excision, but there are at least two pathways for 5' directed excision,one of which is a PCNA-independent 5' excision pathway. To determine if RPAphosphorylation facilitates DNA resynthesis, a gap-filling assay was developedusing both a cell-free system and a purified system, and we demonstrate that RPAphosphorylation stimulates DNA polymerase ??-catalyzed resynthesis in bothsystems. Kinetic studies indicate that phosphorylated RPA has a lower affinity forDNA compared with un-phosphorylated RPA. Therefore, the stimulation ofresynthesis by phosphorylated RPA is likely due to the fact that phosphorylationpromotes the release of RPA from DNA, thereby making DNA template availablefor resynthesis.
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Nóbrega, Judas Tadeu Nunes. "SEPULTAMENTOS PRÉ-HISTÓRICOS: UM PROTOCOLO ALTERNATIVO PARA EXTRAÇÃO DE DNA DOS OSSOS ANTIGOS NO BIOMA CERRADO DO BRASIL CENTRAL." Pontifícia Universidade Católica de Goiás, 2012. http://localhost:8080/tede/handle/tede/2356.
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Previous issue date: 2012-03-29Archeology, from the Greek archaios (ancient) and logos (study), is the science that studies the material culture of past societies in order to understand their structure, how they work, and how change occurs. Finding the origins of the American man is one of its challenges. Among the theories put forward to explain the origins of the American man, the most famous affirms that Homo sapiens crossed the Bering Strait, having migrated from Africa 150.000 BCE, eventually occupying, at the end of the Pleistocene and the beginning of the Holocene, the last great landmass of the Earth: the Americas. The genetic mapping of haplogroups may be a positive evidence for that hypothesis. But if primitive man spread throughout the Americas, one needs to know who the central Brazilian Cerrado inhabitants were, whose skeletal material was found in various archeological sites. Dated material found in archeological sites point to more than 7.000 years ago. In order to know who were those people, we need to classify them into haplogroups. The first step is the collection of DNA, which is difficult because of contamination and bad weather in the cerrado. Once bones and teeth were provided, the search for a protocol for efficient DNA extraction began, going through countless trials and modifications of existing methods. More than one hundred extraction trials were done, finally concluding an adapted protocol with greater amounts of certain substances, which was used to extract DNA from 32 bone and tooth samples collected in various archeological sites. The extracted material was quantified and presented to PCR for the amplification of the ZFX/Y gene, having as a control DNA extracted from peripheral human blood through NaCl technique, after it was proved that they were human bones and teeth. Having established an efficient alternative protocol for DNA extraction, the task of sequencing and identification of primitive peoples of the central Brazilian Cerrado is made easier.
Arqueologia, Archaios = antigo, passado e Logos = estudo, ciência que estuda a cultura material das sociedades passadas, objetivando compreender a estrutura, funcionamento e processos de mudanças daquelas sociedades. Elucidar a origem do homem americano é um de seus desafios e dentre as teorias existentes tem mais notoriedade a travessia, do homo sapiens, pelo estreito de Bering, migrando para fora da África a partir de 150.000 anos antes do presente (AP), terminando por ocupar, no final do pleistoceno e início do holoceno o último grande reduto da Terra: as Américas. O mapeamento genético dos haplogrupos sinaliza positivamente para essa hipótese porém se o homem se dispersou por todas as Américas procura-se saber quem eram os moradores primitivos do Bioma Cerrado do Brasil Central cujo material esqueletal foi encontrado em diversos sítios arqueológicos. O material encontrado em sítios arqueológicos, datados, apontam para mais de 7 mil anos antes do presente e com o intuito de saber quem eram esses povos que para aqui migraram é necessário classificá-los haplotipicamente sendo o passo inicial a obtenção do DNA, de difícil extração em virtude das contaminações e intempéries próprias do Bioma Cerrado. Com a obtenção dos ossos e dentes fornecidos pela academia Arqueológica a busca de um protocolo para extração de DNA, eficiente, passou por inúmeras tentativas e modificações de métodos já existentes. Mais de uma centena de tentativas de extração de DNA foram realizadas, concluindo finalmente um protocolo, adaptado, com maiores quantidades de determinadas substâncias e utilizado para extração de DNA de 32 amostras de ossos e dentes de diversos sítios arqueológicos. O material extraído foi quantificado e submetido à PCR para amplificação do gene ZFX/Y tendo como controle DNA extraído de sangue periférico humano pela técnica de NaCl, e sendo comprovado serem ossos e dentes humanos. Estabelecido um protocolo alternativo, eficiente, para extração de DNA fica menos árdua a tarefa de sequenciamento e identificação dos povos primitivos do bioma Cerrado no Brasil Central.
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Mosolits, Szilvia. "Natural and induced immunity aginst the tumour-associated antigen, Ep-CAM /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-752-5.
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Suschak, John J. III. "Characterization of Innate Immune Pathways in DNA Vaccine-Induced, Antigen-Specific Immune Responses: A Dissertation." eScholarship@UMMS, 2014. https://escholarship.umassmed.edu/gsbs_diss/748.
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A major advantage of DNA vaccination is the ability to induce both humoral and cellular immune responses. DNA vaccines are currently used in veterinary medicine, but their tendency to display low immunogenicity in humans has hindered their usage, despite excellent tolerability and safety profiles. Various approaches have been used to improve the immunogenicity of DNA vaccines. Recent human study data re-established the value of DNA vaccines, especially in priming high-level antigen-specific antibody responses. Data suggests that innate immune responses to the DNA vaccine plasmid itself contribute to the immunogenicity of DNA vaccines, however the underlying mechanisms responsible remain unclear. In this dissertation, we investigate the role of innate immunity in shaping antigen-specific adaptive immune responses following DNA vaccination.
The current belief is that the cytosolic DNA sensing pathways govern DNA vaccine immunogenicity. To date, only the type I interferon inducing STING/TBK1 regulatory pathway has been identified as required for DNA vaccine immunogenicity. Surprisingly, neither the upstream receptor nor the downstream signaling molecules in this pathway have been characterized. I therefore investigated a candidate cytosolic DNA receptor, as well as the downstream transcription factors required for generation of antigen-specific immune responses. Additionally, the effects of pro-inflammatory signaling on DNA vaccine immunogenicity have yet to be comprehensively studied. Previous studies have only provided indirect evidence for the role of inflammatory v signaling in DNA vaccination. As such, I also investigated the role of the DNA sensing AIM2 inflammasome in DNA vaccination. My data indicates that AIM2 is a key modulator in DNA vaccination via a previously unrecognized connection to type I interferon. Importantly, this marks the first time a DNA vaccine sensor has been identified.
Of note, this dissertation represents a departure from many published works in the field. Whereas previous studies have mostly utilized model antigens and only focused on the adaptive immune responses generated, I analyzed the effects on innate immunity as well. Using various innate gene knockout murine models, I quantified antigen-specific humoral and T cell responses, as well as serum cytokine and chemokines following immunization with a clinically relevant DNA vaccine. Overall, this data provides a basis for understanding the mechanisms of DNA vaccination, allowing for the design of more effective vaccines.
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Suschak, John J. III. "Characterization of Innate Immune Pathways in DNA Vaccine-Induced, Antigen-Specific Immune Responses: A Dissertation." eScholarship@UMMS, 2012. http://escholarship.umassmed.edu/gsbs_diss/748.
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A major advantage of DNA vaccination is the ability to induce both humoral and cellular immune responses. DNA vaccines are currently used in veterinary medicine, but their tendency to display low immunogenicity in humans has hindered their usage, despite excellent tolerability and safety profiles. Various approaches have been used to improve the immunogenicity of DNA vaccines. Recent human study data re-established the value of DNA vaccines, especially in priming high-level antigen-specific antibody responses. Data suggests that innate immune responses to the DNA vaccine plasmid itself contribute to the immunogenicity of DNA vaccines, however the underlying mechanisms responsible remain unclear. In this dissertation, we investigate the role of innate immunity in shaping antigen-specific adaptive immune responses following DNA vaccination.
The current belief is that the cytosolic DNA sensing pathways govern DNA vaccine immunogenicity. To date, only the type I interferon inducing STING/TBK1 regulatory pathway has been identified as required for DNA vaccine immunogenicity. Surprisingly, neither the upstream receptor nor the downstream signaling molecules in this pathway have been characterized. I therefore investigated a candidate cytosolic DNA receptor, as well as the downstream transcription factors required for generation of antigen-specific immune responses. Additionally, the effects of pro-inflammatory signaling on DNA vaccine immunogenicity have yet to be comprehensively studied. Previous studies have only provided indirect evidence for the role of inflammatory v signaling in DNA vaccination. As such, I also investigated the role of the DNA sensing AIM2 inflammasome in DNA vaccination. My data indicates that AIM2 is a key modulator in DNA vaccination via a previously unrecognized connection to type I interferon. Importantly, this marks the first time a DNA vaccine sensor has been identified.
Of note, this dissertation represents a departure from many published works in the field. Whereas previous studies have mostly utilized model antigens and only focused on the adaptive immune responses generated, I analyzed the effects on innate immunity as well. Using various innate gene knockout murine models, I quantified antigen-specific humoral and T cell responses, as well as serum cytokine and chemokines following immunization with a clinically relevant DNA vaccine. Overall, this data provides a basis for understanding the mechanisms of DNA vaccination, allowing for the design of more effective vaccines.
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Goldmann, Katja [Verfasser], and Thomas [Akademischer Betreuer] Winkler. "Immunmodulation druch orale Applikation von Antigen kodierenden Chitosan-DNA Nanopartikeln / Katja Goldmann. Betreuer: Thomas Winkler." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2012. http://d-nb.info/1022002171/34.
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Peng, Yu-Cai 1965. "Interactions between polyomavirus large T antigen and the viral replication origin DNA : how and why." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35927.
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Polyomavirus large T antigen is the major regulatory protein in the polyomavirus life cycle. It binds to multiple G(A/G)GGC pentanucleotide sequences in sites 1/2, A, B, and C within and adjacent to the origin of viral DNA replication on the polyomavirus genome. The nature of interactions between large T antigen and the viral origin of DNA replication is not fully understood. We set out to produce large T antigen protein in the methylotropic yeast Pichia pastoris by placing the large T antigen gene downstream of the strong alcohol oxidase (AOX1) promoter. Large T antigen was purified by immuno-affinity chromatography by using a monoclonal antibody.While optimizing the conditions for binding of large T antigen to viral origin DNA, we discovered that binding was substantially stronger at pH 6 to 7 than at pH 7.4 to 7.8, a range often used in DNA binding assays. We showed that increased binding at low pH is due to increased stability of protein-DNA complexes, and that large T antigen molecules self-associated at low pH, forming massive complexes. ATP increased binding of large T antigen to origin DNA by about 2-fold at pH 7.8, but had no detectable effect at pH 7 or below.
Enhanced, stable DNA binding by large T antigen to viral origin DNA at pH 6 enabled us to develop a novel gel mobility shift assay using unfixed protein-DNA complexes. We demonstrated that this assay is very sensitive and highly specific. This method can be used both for detection of large T antigen in crude cell lysates and for quantitation of binding of purified large T antigen to target DNAs under various conditions.
Using a series of point and deletion mutants in the viral origin of DNA replication, we demonstrated that binding of large T antigen to sites 1/2, A, B, and C is cooperative. Binding of large T antigen to one site stimulated binding to other sites 20 to 100 bp distant, and binding to inherently weak sites was strengthened if two or more such sites were present on the same DNA molecule. These findings suggest that large T antigen molecules bound to DNA interact with each other to mutually stabilise their binding.
ATP was shown to stabilise large T antigen-DNA complexes against dissociation only if the DNA contained site 1/2. ATP specifically enhanced protection against DNase I digestion in the central 10 to 12 bp of site 1/2, where hexamers are believed to form and begin unwinding DNA. We propose a model in which large T antigen molecules bound to sites 1/2, A, B, and C on origin DNA form a compact protein-DNA complex via mutual interactions; large T antigen molecules bound to sites A, B, and C are mobilised and "handed over" to site 1/2, where ATP stimulates their assembly into hexamers.
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Peng, Yu-Cai. "Interactions between polyomavirus large T antigen and the viral replication origin DNA, how and why." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0028/NQ50235.pdf.
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Lau, Patrick J. "Characterization of the proliferating cell nuclear antigen (PCNA) in the context of DNA mismatch repair /." Diss., Connect to a 24 p. preview or request complete full text in PDF formate. Access restricted to UC campuses, 2002. http://wwwlib.umi.com/cr/ucsd/fullcit?p3071043.
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Ou, Zhonghui. "Structure of an antigen-binding fragment bound to stem-loop DNA and crystallization of recombinant haemophilus influenzae e(P4) acid phosphatase." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4621.
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Thesis (M.S.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 17, 2009) Includes bibliographical references.
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Torres, Celia Aurora Tiglao. "DNA Immunization: Role of Target Site, Bone Marrow-Derived Cells and Secretion of Antigen in the Initiation of Immune Responses: A Dissertation." eScholarship@UMMS, 1998. https://escholarship.umassmed.edu/gsbs_diss/293.
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DNA immunization, or the use of antigen-expressing DNAs to raise immune responses, represents a novel approach to the study and manipulation of immune responses. In this dissertation, we examine the role of antigen expression at the target site, the role of antigen presentation by bone marrow-derived cells, and the effect of secretion of antigen on DNA-raised responses in mice. Immunizations were conducted using either gene gun delivery of DNA to the epidermis or intramuscular (i.m.) saline injections.
To examine the role of antigen expression at the target site, we excised target sites at different time points following immunization. We immunized with plasmid DNA expressing three different forms of antigens: influenza hemagglutinin H1, human growth hormone and influenza nucleoprotein NP (membrane-bound, secreted and intracellular, respectively). We hypothesized that antigen expression at the target site would be essential in initiating immune responses. We demonstrate here that the target site plays different roles in gene gun and i.m. immunizations. We found that the skin target site played an essential role in eliciting maximal antibody and cytotoxic T lymphocyte (CTL) responses by gene gun immunization, although low-level responses can be raised independent of the target site. In contrast, the muscle target site was not essential for eliciting maximal immune responses following i.m. immunization. We suggest that gene gun immunization results in transfection of keratinocytes and bone marrow-derived Langerhans cells at the target site, and these cells together initiate maximal responses. In i.m. immunizations, on the other hand, nonmuscle cells at distal sites, perhaps bone marrow-derived cells in lymphoid tissues, become transfected and are sufficient for initiation of maximal responses.
We also examined the role of antigen presentation by bone marrow-derived cells in initiation of CTL responses to influenza NP following gene gun and i.m. immunization. We hypothesized that antigen presentation by bone marrow-derived cells would be involved in initiation of CTL responses. To test this hypothesis, irradiated F1 mice of MHC class I H-2bxd haplotype were reconstituted with bone marrow from either H-2b or H-2d donors, creating two sets of bone marrow chimeric mice (H-2b → H-2bxd and H-2d → H-2bxd, respectively). We immunized the two sets of bone marrow chimeric mice and determined the MHC haplotype restriction of the induced CTL responses using H-2b- or H-2d-restricted peptides of NP. We found that the CTL responses initiated following gene gun and i.m. immunization were restricted to the haplotype of the bone marrow donor. In H-2b→ H-2bxd chimeric mice, CTL responses were restricted to H-2b, while in H-2d→ H-2bxd chimeric mice, CTL responses were restricted to H-2d. Thus, antigen presentation by bone marrow-derived cells, and not by skin or muscle cells, initiates CTL responses following both gene gun and i.m. immunization.
Finally, we examined the effect of secretion of a DNA-expressed antigen on antibody responses. We hypothesized that a secreted antigen would raise greater antibody responses than a membrane-bound antigen, due to easier access of a soluble antigen to lymphoid tissues and to uptake by professional antigen-presenting cells and by antigen-specific B cells. We immunized mice with plasmid DNA expressing either a secreted or the normal membrane-bound form of influenza hemagglutinin H1. We found that secretion of H1 (sH1) did not result in enhanced antibody responses, with sH1 appearing to be less effective than H1. We suggest that the effectiveness of DNA immunization with membrane-bound H1 in raising maximal antibody responses may be due to MHC class II presentation of H1 via an endogenous pathway, resulting from direct transfection of bone marrow-derived APCs.
We also found that secretion of H1 influenced the predominant IgG subclass of antibody responses raised by i.m. immunization. Secreted H1 raised predominantly IgG1 responses and H1 raised predominantly IgG2a responses. The IgG1 response to sH1 following i.m. immunization was IL-4 dependent, suggesting that the response to sH1 had a T-helper type 2 phenotype.
We propose a model for the mechanism of initiation of immune responses by DNA immunization based on our results and taking them within the context of results from other investigators in the field. We propose that DNA immunization may initiate immune responses primarily by the direct transfection of bone marrow-derived cells that then express and present the DNA vaccine-encoded antigen. However, antigen expression by nonhemopoietic cells, particularly in skin, may play a role in raising maximal responses.
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Villa, Valentina [Verfasser], Johannes [Akademischer Betreuer] Buchner, and Ariza José Antonio [Akademischer Betreuer] Garrido. "Electro-switchable DNA layers for the analysis of antibody-antigen and p53-DNA interactions / Valentina Villa. Gutachter: José Antonio Garrido Ariza ; Johannes Buchner. Betreuer: Johannes Buchner." München : Universitätsbibliothek der TU München, 2012. http://d-nb.info/1031550380/34.
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Babakhani, Farah Kondori 1960. "IN VITRO PRODUCTION AND SPECIFICITY OF ANTI-DNA AUTO ANTIBODIES BY NEW ZEALAND BLACK/NEW ZEALAND WHITE F1 MICE." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276471.
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Liao, Wenqing. "Development of Nanostructured DNA Aimed at Enhancing the Stability and Antigen-presenting Cell Targetability of CpG Oligodeoxynucleotide." Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/253234.
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京都大学0048
新制・課程博士
博士(薬科学)
甲第22398号
薬科博第120号
新制||薬科||13(附属図書館)
京都大学大学院薬学研究科薬科学専攻
(主査)教授 髙倉 喜信, 教授 山下 富義, 教授 小野 正博
学位規則第4条第1項該当
Doctor of Pharmaceutical Sciences
Kyoto University
DFAM