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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.
101

Conifer Evolution, from Demography and Local Adaptation to Evolutionary Rates : Examples from the Picea genus

Chen, Jun January 2012 (has links)
Evolutionary process can be inferred at three different levels: the species level, the population level and the molecular level. In this thesis, I applied approaches at these three levels and aimed to get a comprehensive picture of conifer evolution, from speciation and demography to geographic variation and local adaptation, and then to the molecular evolution of proteins and small regulatory RNAs. Spruce species have been observed to possess a large number of trans-species shared polymorphisms. Using an “Isolation with migration” model, we found that the large effective population size of spruce retained these shared polymorphisms, inheriting them from the common ancestor. Post-divergence gene flow only existed between Picea abies and P. glauca, and between P. wilsonii and P. schrenkiana. The combination of Tajima’s D and Fay & Wu’s H at most of loci suggested an ancient and severe bottleneck for most species except P. breweriana. Furthermore, I investigated the effect of local selection in two parallel clines, which is one of the major forces that can cause divergence or even speciation. The timing of bud set and growth cessation was found correlated with latitude in populations of P. abies and P. obovata. Using allele frequency spectrum analyses we identified three genes under local selection in both species including two circadian-clock genes GI and PRR7, and one photoperiodic gene FTL2. This indicated that parallel evolution could occur through groups of genes within related pathways. Clinal variation at expression level provided stronger evidence of selection in FTL2, which has previously been associated with bud set in P. abies. Finally we focused on the molecular evolution of mRNA and small regulatory RNAs in P. abies. With the help of Next-Generation sequencing, we have achieved in spruce the first de novel assembly of the needle transcriptome and a preliminary characterization of sRNA populations. Along with features common in plants, spruce also exhibited novelties in many aspects including lower substitution rate and protein evolutionary rate, dominance of 21-nt sRNA, and a large proportion of TIR-NBS-LRR genes as sRNA sources and targets.
102

Short sequence tags reveal global transcription of repetitive elements in mammalian genomes

Geoffrey Faulkner Unknown Date (has links)
Retrotransposon mobilization is a major source of genome evolution. However, the functional consequences of these events, and particularly their influence upon transcriptional activity, are poorly defined. The extent of retrotransposon transcription, as well as that of other repetitive elements, has eluded systematic study due to difficulties in discriminating elements copied in multiple genomic loci. Moreover, the potential regulatory effects of retrotransposon transcription upon the expression of neighbouring protein-coding genes are also largely unknown. This thesis develops methods to survey repetitive element expression and assess the functions of retrotransposons in the mouse and human genomes. Chapter 1 summarises the complex transcriptional output of the mammalian genome, the functional annotation of this expression and the genomic and bioinformatic tools available for its detection. Chapter 2 explores the capacity of short sequence tags to discern transcription from individual repetitive elements, as well as from protein-coding genes. It is based upon a publication that critiqued the bioinformatics associated with Cap Analysis Gene Expression (CAGE) and developed novel methodologies to resolve repetitive element transcription. Chapter 3 describes the development of an updated CAGE mapping pipeline for the fourth stage of the international Functional Annotation of Mouse (FANTOM) project, which lead to the generation of a research article and a book chapter. These works demonstrated the enhanced utility of CAGE when coupled with next-generation sequencing, highlighted the benefits of CAGE when applied to systems biology and profiled the temporal expression of human repetitive elements. Chapter 4 presents an in-depth analysis of repetitive element transcription in the mouse and human genomes. Using CAGE, approximately 250,000 retrotransposon associated transcription start sites were defined, many of which were tissue-specific. Retrotransposons were found to frequently function as alternative promoters for protein-coding genes and/or express non-coding RNAs. Furthermore, when retrotransposons were found within the 3’UTR of protein-coding genes, there was strong evidence for the reduced expression of the corresponding transcripts. A genome-wide screen for strong expression correlation between repetitive elements and neighbouring protein-coding genes identified approximately 23,000 candidate regulatory regions derived from retrotransposons, including several hundred putative boundary elements. These were in addition to more than two thousand examples of bidirectional transcription found in retrotransposons, which are known to be a source of double stranded RNAs involved in RNA interference. Chapter 5 explores the proportion of the mouse embryonic stem cell transcriptome comprised of repeat-derived transcripts, using next-generation RNA sequencing. This study defined the dynamic expression of repetitive elements at the greatest resolution achieved to date and demonstrated that repetitive elements are an intrinsic part of the mammalian transcriptional landscape.
103

Relationship among dietary fats, fatty acid profile and expression of genes involved in testes function in Zucker (fa/fa) rats

Datar, Jutika 08 January 2016 (has links)
Six week old male obese fa/fa Zucker rats (n=10/group) were fed four different diets enriched in linoleic acid (LA), α-linolenic acid (ALA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) (safflower oil, flaxseed oil, EPA, and DHA oils, respectively) for 8 weeks. Fatty acids were analyzed in major lipid classes in the testes. Global gene expression was analyzed using the Affymetrix Rat Gene 2.0 ST Array. Annotated gene sets from the normal and underdeveloped testes were analyzed using Ingenuity Pathway Analysis (IPA). In lipid analysis, n-3 diet supplementation decreased n-6: n-3 polyunsaturated fatty acid and n-6: n-3 very long chain fatty acids (VLCFA) in most lipid classes in comparison to the LA diet. ALA increased the level of DHA, but not to the same level as DHA diet. Compared to the normal sized testis, the underdeveloped testis showed a marked decrease in n-6 pentaenoic PUFA and VLCFA while increasing n-6 tetraenoic fatty acids. Out of the 3192 genes detected, 1121 and 309 were differentially expressed in the underdeveloped and normal testes, respectively. The IPA indicated that transcripts that are upregulated in the normal testes relative to underdeveloped testes are involved in triacylglycerol biosynthesis, sphingomyelin metabolism and phosphatidylglycerol biosynthesis. Transcripts upregulated in underdeveloped testes relative to normal testes are involved in production of nitric oxide and reactive oxygen species. Downstream effect analysis showed an increased trend towards reproductive system diseases and endocrine system disorders in the underdeveloped testes compared to the normal testes. In conclusion, these results indicate that testicular lipids and their metabolism are closely related with normal testis development and function. / February 2016
104

Identificação de genes-alvos na patogenicidade de Xanthomonas citri subsp. citri com enfoque no sistema de secreção tipo III /

Mendoza, Elkin Fernando Rodas January 2016 (has links)
Orientador: Jesus Aparecido Ferro / Coorientador: Flávia Maria de Souza Carvalho / Coorientador: Roberto Hirochi Herai / Banca: Henrique Ferreira / Banca: José Belasque Júnior / Banca: Marcos Túlio de Oliveira / Banca: Alessandro de Mello Varani / Resumo: Xanthomonas citri subsp. citri (Xac) é o agente causal do cancro cítrico, uma das principais doenças que acometem a citricultura mundial. Atualmente não há uma maneira eficiente de controle do cancro, e novos métodos devem ser desenvolvidos para o tratamento desta doença. Assim, o estudo dos mecanismos utilizados pela Xac durante o processo infeccioso pode revelar novos alvos para o desenvolvimento de compostos farmacológicos que possam eliminar ou controlar o patógeno. Neste estudo, a técnica de RNA-Seq foi utilizada para a identificação de genes diferencialmente expressos (GDE) na Xac em condições in vivo e in vitro. Para isso, cinco variedades de citros com níveis diferentes de suscetibilidade ao cancro cítrico, e meios de cultura indutores de fatores de virulência foram utilizados. Muitos dos genes que codificam para proteínas relacionadas ao sistema de secreção tipo 3 (T3SS), enzimas extracelulares, resposta ao estresse oxidativo, transportadores de ferro e fósforo foram induzidos pela Xac nas condições in vivo. No entanto, in vitro, os perfis de expressão para estes mesmos genes foram diferentes. Estes dados permitiram compreender melhor o ambiente intracelular do hospedeiro, e como este se relaciona com os mecanismos de ativação dos fatores de virulência e patogenicidade de Xac. Neste sentido, os dados apresentados neste estudo mostraram que o T3SS é o principal fator de virulência expresso por esta bactéria em condições in vivo. Além disso, nossos resultados sugerem t... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Xanthomonas citri subsp. citri (Xac) is the causal agent of citrus canker, a major disease affecting citrus worldwide. Currently there is no effective way of cancer control, and new methods must be developed for the treatment of this disease. Thus, the study of the mechanisms used by Xac during the infectious process can reveal new targets for the development of pharmacologic compounds that can eliminate or control the pathogen. In this study, RNA-Seq technique was used to identify Xac differentially expressed genes (DEG) in vivo and in vitro conditions. For this purpose, five citrus varieties with different levels of susceptibility to citrus canker and culture mediums inducing virulence factors were used. Many of the genes encoding proteins of the type 3 protein secretion system (T3SS), extracellular enzymes, oxidative stress response, iron and phosphorus transport were induced in Xac in vivo conditions. However, the expression profiles for these same genes were different than observed in vitro conditions. These data allowed us to better understand the intracellular environment of the host, and how this relates to the activation mechanisms of pathogenicity and virulence factors in Xac. In this context, the data presented in this study show the T3SS as the main virulence factor expressed by the bacteria in vivo conditions. Furthermore, our results also suggest that low concentrations of inorganic phosphorus (Pi) and nitrogen, that bacteria sense in the plant apoplast, are ... (Complete abstract click electronic access below) / Doutor
105

Expressão gênica diferencial em tecido muscular de bovinos Nelore divergentes para qualidade de carne / Differential gene expression in Nellore cattle muscle tissue divergently ranked on meat quality

Fonseca, Larissa Fernanda Simielli [UNESP] 07 March 2016 (has links)
Submitted by la_simielli@yahoo.com.br (la_simielli@yahoo.com.br) on 2016-04-05T13:12:40Z No. of bitstreams: 1 TESE_LARISSA_FERNANDA_SIMIELLI_FONSECA.pdf: 1971633 bytes, checksum: 177f6a3044467459f559bbf217ba550f (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-06T20:32:27Z (GMT) No. of bitstreams: 1 fonseca_lfs_dr_jabo.pdf: 1971633 bytes, checksum: 177f6a3044467459f559bbf217ba550f (MD5) / Made available in DSpace on 2016-04-06T20:32:27Z (GMT). No. of bitstreams: 1 fonseca_lfs_dr_jabo.pdf: 1971633 bytes, checksum: 177f6a3044467459f559bbf217ba550f (MD5) Previous issue date: 2016-03-07 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Mais de 80% da carne bovina brasileira é proveniente de animais de origem zebuína. Este produto é considerado de baixa maciez e reduzido teor de gordura entremeada quando comparado à carne de animais de raças taurinas. Investir na melhoria das características organolépticas como marmoreio e maciez da carne torna-se importante do ponto de vista econômico, pois tratam-se de atributos muito apreciados pelo consumidor. A maciez pode ser medida por meio de análises sensoriais, índice de fragmentação miofibrilar ou força de cisalhamento. Nesse último, um aparelho é utilizado para medir a força necessária para o cisalhamento de uma seção transversal de carne e, quanto maior a força dispensada, menor é a maciez apresentada pelo corte de carne. Outra característica relacionada à qualidade da carne é o marmoreio, que pode ser analisada por meio de escala de graduação visual denominada Quality Grade. No entanto, estas metodologias só podem ser utilizadas após o abate do animal. As técnicas de análise do transcriptoma, como o RNA-Seq, permitem a identificação de genes cuja expressão está relacionada com o controle de características quantitativas e podem ser alternativas na busca pelo melhoramento destes atributos. Com isso, o objetivo deste trabalho foi identificar genes diferencialmente expressos utilizando a técnica RNA-Seq, em tecido muscular de bovinos da raça Nelore, visando contribuir para o conhecimento dos fatores genéticos que estão relacionados com a qualidade da carne. Para isso, foi sequenciado o mRNA de 40 amostras divergentes para a maciez da carne (20 com carne dura e 20 com carne macia) e 40 amostras divergentes para marmoreio (20 com alto e 20 com baixo marmoreio). Essas amostras foram escolhidas com base na análise de força de cisalhamento e índice de marmorização realizadas em 132 e 80 amostras de músculo longissimus dorsi respectivamente, coletadas da meia carcaça esquerda de cada animal. As análises dos resultados obtidos pela técnica de RNA-Seq revelaram genes diferencialmente expressos relativos à maciez e marmoreio da carne em gado Nelore. Os genes referentes à maciez estão relacionados ao metabolismo de colágeno, à actina e miosina, ao transporte de cálcio, dentre outros. Por outro lado, nos resultados das análises de marmoreio, os genes que se mostraram diferencialmente expressos estão relacionados à ocitocina, ao transporte de oxigênio, ao crescimento e à síntese de lipídios e proteínas. Portanto, este estudo revelou a possibilidade de se utilizar alguns desses genes diferencialmente expressos como marcadores genéticos em bovinos Nelore para seleção precoce quanto à maciez e marmoreio da carne. / More than 80% of Brazilian beef comes from zebu animals. The Zebu meat show reduced marbling and is considered harder when compared to Taurine meat. The improvement of the organoleptic traits like marbling and meat tenderness is important from an economic point of view, because these attributes are highly appreciated by the consumer. The meat tenderness can be measured by sensory analysis, myofibril fragmentation index or by shear force. This method use an apparatus which measure the force required to shear a cross section of meat. The higher the strength dispensed, lower is the tenderness showed by the cut of meat. Another trait related to meat quality is marbling, which can be analyzed by Quality Grade visual graduation scale. However, these methods can only be performed after the animal was killed. The transcriptome analysis techniques, as RNA-Seq, are able to identify genes whose expression are related to quantitative traits control and can be used as alternative to help the improvement of these traits. Thus, the aim of this study was to identify differentially expressed genes using RNA-Seq, in Nelore cattle muscular tissue, to contribute to the knowledge of the genetic factors that are related to meat quality. We sequenced the mRNA of 40 samples divergently ranked to meat tenderness (20 with hard meat and 20 with tender meat) and sequenced the mRNA of 40 samples divergently ranked to marbling (20 with high and 20 with low marbling). These samples were chosen based on shear force and marbling content analysis held at 132 and 80 longissimus dorsi muscle samples respectively, collected from each left half carcass. The analysis of the results obtained by RNA-Seq technique revealed differentially expressed genes related to meat tenderness and marbling in Nelore cattle. Regarding the meat tenderness, these genes are related to collagen metabolism, actin and myosin, the calcium transport, among others. Moreover, the marbling analysis results, revealed differentially expressed genes related to oxytocin, transport of oxygen, growth and lipids and proteins synthesis. Therefore, this study showed the possibility of using some of these differentially expressed genes as genetic markers in Nellore cattle for early selection to meat tenderness and marbling. / FAPESP: 2013/09190-7
106

Análise da expressão gênica celular e viral durante a infecção in vitro pelo herpesvírus canino 1

Kurissio, Jacqueline Kazue. January 2017 (has links)
Orientador: João Pessoa Araújo Junior / Resumo: A análise de transcriptoma é essencial para determinar a relação entre as informações codificadas num genoma, a sua expressão e variação genotípica. O transcriptoma é o conjunto completo de transcritos e a quantidade gerada, relacionado a um estágio de desenvolvimento específico ou condição fisiológica da célula. Estes transcritos podem ser mapeados utilizando genomas como referência, para investigação de expressão do genes. Para isso, exige procedimentos de mineração de grandes volumes de dados de RNA-Seq para extrair conhecimentos biológicos. As ferramentas de bioinformática foram desenvolvidas para facilitar e agilizar essas análises, transformando dados em informações. Assim, alguns desses recursos foram empregados na análise de dados gerados pelo RNAseq, a partir de RNAm de cultura celular MDCK infectada por herpesvírus canino tipo 1 (1CaHV-1 - Canid alphaherpesvirus type 1) em diferentes momentos pós infecção. Dessa forma, foi realizado um dual RNAseq, em que foi avaliado tanto a expressão gênica celular do hospedeiro como do patógeno viral, no curso da infecção. Para isso, foram analisados o transcriptoma das atividades celulares e os processos envolvidos no ciclo de infecção viral, até o momento 32h-pi. Assim, foram identificados as atividades de respostas celulares à infecção viral, mecanismos regulatórios induzidos pelo vírus, transcrição de genes virais imediatos, iniciais e tardios. Dentre eles, foi verificado a elevação da expressão do gene COX-2 induzido pela... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
107

Sequenciamento do transcriptoma e caracterização de microssatélites na pirapitinga Piaractus brachypomus para análises de variabilidade genética / Genetic characterization of the fish Piaractus brachypomus by microsatellites derived from transcriptome sequencing

Jorge, Paulo Henrique [UNESP] 25 February 2016 (has links)
Submitted by Paulo Henrique Jorge (paulohj@ibb.unesp.br) on 2016-09-21T21:22:43Z No. of bitstreams: 1 Tese Paulo.pdf: 2340897 bytes, checksum: 4d1a3bab6d4520ebb58d8720feafa105 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-09-22T18:14:15Z (GMT) No. of bitstreams: 1 jorge_ph_me_bot.pdf: 2340897 bytes, checksum: 4d1a3bab6d4520ebb58d8720feafa105 (MD5) / Made available in DSpace on 2016-09-22T18:14:15Z (GMT). No. of bitstreams: 1 jorge_ph_me_bot.pdf: 2340897 bytes, checksum: 4d1a3bab6d4520ebb58d8720feafa105 (MD5) Previous issue date: 2016-02-25 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A pirapitinga, Piaractus brachypomus (Characiformes, Serrasalmidae), é um peixe de ocorrência na bacia Amazônica e uma das principais espécies nativas utilizadas para a produção em aquicultura. O principal objetivo deste estudo foi realizar o sequenciamento do transcriptoma de P. brachypomus por meio de Sequenciamento de Nova Geração (NGS) e, em seguida, caracterizar um conjunto de marcadores microssatélites para esta espécie. Além disso, marcadores microssatélites polimórficos foram usados para realizar a análise da variabilidade genética em estoques cultivados de pirapitinga. O sequenciamento do transcriptoma foi realizado por meio da tecnologia 454/Roche, que resultou em 3.696 contigs não reduntantes (nr). Destes 2.568 genes com correspondência no banco de proteínas (nr) foram caracterizados nas categorias de Gene Ontology (GO), sendo que 2.075 sequências (80,8%) foram anotadas em termos GO. Dos 30 loci de microssatélites, após o processo validação, 8 loci de microssatélites demonstraram polimorfismo. A análise desses marcadores polimórficos em estoques cultivados revelou que as pisciculturas do Norte apresentaram uma maior variabilidade genética (riqueza de alelos e heterozigosidade) do que as Pisciculturas do Sudeste. Além disso, os resultados da AMOVA demonstraram que a maior variação estava presente dentro das populações (62,5%). Entretanto, quando comparado os grupos de acordo com a origem (Selvagem, Pisciculturas do Norte e Pisciculturas do Sudeste), foi verificada uma variação considerável (31,76%) entre os grupos. Estes dados foram corroborados com os valores de Fst, pois houve alta estruturação genética entre os estoques cultivados e a população selvagem, bem como também entre as Pisciculturas do Norte e do Sudeste. A estratégia de sequenciamento do transcriptoma por NGS se demonstrou eficaz na prospecção de marcadores moleculares, além de gerar um alto volume de recursos genéticos para serem explorados em diversas áreas da biologia. Os microssatélites gerados nesse estudo são importantes ferramentas para serem empregadas no manejo genético de estoques de reprodutores cultivados, o que poderá aumentar a produtividade em sistemas de produção e gerar um alto valor agregado do pescado com qualidade genética. / The pirapitinga, Piaractus brachypomus (Characiformes, Serrasalmidae), is a fish that occurrs in the Amazon basin and it is considered as one of the main native species used for production in aquaculture in South America. The main objectives of this study were: 1) to perform the transcriptome sequencing of P. brachypomus through Next Generation Sequencing (NGS) and then characterize a set of microsatellite markers for this species; 2) to apply microsatellite polymorphic markers for analysis of genetic variability in cultured stocks of pirapitinga. The transcriptome sequencing was carried out through the Roche/454 technology, which resulted in 3,696 non-redundant (nr) contigs. Of these total, 2,568 genes had similarity in the protein database nr (Genbank) and were characterized in the categories of Gene Ontology (GO), with 2,075 sequences (80.8%) annotated in GO terms. After the validation process of 30 microsatellite loci, 8 microsatellite markers showed polymorphism. The analysis of these polymorphic markers in cultured stocks revealed that the Northern fish farms had a higher genetic diversity (allele richness and heterozygosity) than the Southeastern fish farms. In addition, the AMOVA results demonstrated the highest variation present within the populations (62.5%). However, when comparing the groups according to the geographic distribution (Wild, North Fish farms and fish farms in the Southeast), it was observed a considerable variation (31.76%) among the groups. The Fst values showed there is a genetic structure among the broodstocks analyzed. Microsatellites generated by transcriptome sequencing in this study are important tools to be used in the genetic management of cultivated breeding stocks, as well to identify different gene banks, which might provide a basis for a genetic pre-breeding program in pirapitinga. / FAPESP: 2014/05732-2
108

Sequenciamento do transcriptoma e caracterização de microssatélites na pirapitinga Piaractus brachypomus para análises de variabilidade genética

Jorge, Paulo Henrique January 2016 (has links)
Orientador: Diogo Teruo Hashimoto / Resumo: The pirapitinga, Piaractus brachypomus (Characiformes, Serrasalmidae), is a fish that occurrs in the Amazon basin and it is considered as one of the main native species used for production in aquaculture in South America. The main objectives of this study were: 1) to perform the transcriptome sequencing of P. brachypomus through Next Generation Sequencing (NGS) and then characterize a set of microsatellite markers for this species; 2) to apply microsatellite polymorphic markers for analysis of genetic variability in cultured stocks of pirapitinga. The transcriptome sequencing was carried out through the Roche/454 technology, which resulted in 3,696 non-redundant (nr) contigs. Of these total, 2,568 genes had similarity in the protein database nr (Genbank) and were characterized in the categories of Gene Ontology (GO), with 2,075 sequences (80.8%) annotated in GO terms. After the validation process of 30 microsatellite loci, 8 microsatellite markers showed polymorphism. The analysis of these polymorphic markers in cultured stocks revealed that the Northern fish farms had a higher genetic diversity (allele richness and heterozygosity) than the Southeastern fish farms. In addition, the AMOVA results demonstrated the highest variation present within the populations (62.5%). However, when comparing the groups according to the geographic distribution (Wild, North Fish farms and fish farms in the Southeast), it was observed a considerable variation (31.76%) among the groups. The Fst ... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
109

Transcriptome and Metabolic Profiling of Premalignant Progression in Barrett's Esophagus

January 2014 (has links)
abstract: Cell-cell interactions in a microenvironment under stress conditions play a critical role in pathogenesis and pre-malignant progression. Hypoxia is a central factor in carcinogenesis, which induces selective pressure in this process. Understanding the role of intercellular communications and cellular adaptation to hypoxia can help discover new cancer biosignatures and more effective diagnostic and therapeutic strategies. This dissertation presents a study on transcriptomic and metabolic profiling of pre-malignant progression of Barrett's esophagus. It encompasses two methodology developments and experimental findings of two related studies. To integrate phenotype and genotype measurements, a minimally invasive method was developed for selectively retrieving single adherent cells from cell cultures. Selected single cells can be harvested by a combination of mechanical force and biochemical treatment after phenotype measurements and used for end-point assays. Furthermore, a method was developed for analyzing expression levels of ten genes in individual mammalian cells with high sensitivity and reproducibility without the need of pre-amplifying cDNA. It is inexpensive and compatible with most of commercially available RT-qPCR systems, which warrants a wide applicability of the method to gene expression analysis in single cells. In the first study, the effect of intercellular interactions was investigated between normal esophageal epithelial and dysplastic Barrett's esophagus cells on gene expression levels and cellular functions. As a result, gene expression levels in dysplastic cells were found to be affected to a significantly larger extent than in the normal esophageal epithelial cells. These differentially expressed genes are enriched in cellular movement, TGFβ and EGF signaling networks. Heterotypic interactions between normal and dysplastic cells can change cellular motility and inhibit proliferation in both normal and dysplastic cells. In the second study, alterations in gene transcription levels and metabolic phenotypes between hypoxia-adapted cells and age-matched normoxic controls representing four different stages of pre-malignant progression in Barrett's esophagus were investigated. Through differential gene expression analysis and mitochondrial membrane potential measurements, evidence of clonal evolution induced by hypoxia selection pressure in metaplastic and high-grade dysplastic cells was found. These discoveries on cell-cell interactions and hypoxia adaptations provide a deeper insight into the dynamic evolutionary process in pre-malignant progression of Barrett's esophagus. / Dissertation/Thesis / Ph.D. Biological Design 2014
110

IdentificaÃÃo, validaÃÃo e anotaÃÃo funcional de marcadores microssatÃlites em genÃtipos de cajueiro anÃo-precoce (Anacardium occidentale var. nanum) utilizando dados de rna-seq / Identification, validation and functional annotation of SSR markers in dwaft cashew tree genotypes (Anacardium occidentale var. nanum) using RNA-Seq data

VitÃria VirgÃnia MagalhÃes Soares 12 February 2016 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O cajueiro (Anacardium occidentale L.) à uma planta nativa do Brasil com grande valor comercial. Isso contribui com a geraÃÃo de milhares de empregos diretos e indiretos, especialmente na RegiÃo Nordeste, em Ãpoca de estiagem. Programas de melhoramento genÃtico vem selecionando cultivares de cajueiro melhores adaptados ao ambiente semiÃrido a fim de colocÃ-lo em um mercado cada vez mais competitivo. A busca por marcadores microssatÃlites pode auxiliar os programas de melhoramento no que diz respeito ao acesso à diversidade genÃtica da espÃcie. O presente trabalho tem como objetivo a identificaÃÃo de marcadores SSR em cajueiro com base no transcriptoma de sementes e folhas, bem como sua validaÃÃo por PCR em diferentes genÃtipos comerciais. Utilizando ferramentas de bioinformÃtica foram encontrados motivos SSRs do tipo di- tri- tetra- penta- e hexanucleotÃdeos, onde o motivo do tipo trinucleotÃdeo foi o mais representativo nos transcritos do cajueiro anÃo CCP 76 e comum variando de 60 a 65%, respectivamente. Os transcritos de cajueiro comum e anÃo CCP 76 compartilham um total de 298 marcadores SSR, destes, 29 foram escolhidos para amplificaÃÃo por PCR, os quais 9 mostraram polimorfismo nos genÃtipos testados. As sequÃncias situadas prÃximas aos marcadores SSR codificam proteÃnas, que em sua maioria pertencem a famÃlias gÃnicas. Pode-se concluir que foram encontrados regiÃes contendo marcadores SSRs na regiÃo transcrita de nove genÃtipos de cajueiro, podendo ser uma ferramenta Ãtil nas anÃlises genÃticas e abrindo perspectivas para o papel endÃgeno dos SSRs na funÃÃo proteica. / The cashew tree is a native plant from Brazil with high market value. This contributes to the generation of thousands direct and indirect jobs, especially in the Northeast region, during dry season. Breeding programs have been selecting cashew cultivars that best adapt to semi-arid environment in order to fit it in the increasingly competitive market. The search for microsatellite markers can assist breeding programs regarding to access to genetic diversity of the species. This study aims to identify SSR markers in the cashew tree based on seeds and leaves transcriptome, as well as assess its validation by PCR technique in different commercial genotypes. Using bioinformatics tools, SSRs motifs from types di- tri- tetra- penta- and hexanucleotides were found. Trinucleotide-type motif was the most representative in transcripts both from dwarf cashew CCP 76 and common cashew, ranging from 60 to 65%, respectively. Transcripts from common cashew and dwarf cashew CCP 76 share a total of 298 SSR markers. 29 of these were selected for amplification by PCR, in which 9 showed polymorphism in genotypes tested. The sequences located near to the SSR markers encode proteins, which mostly belong to gene families. It can be concluded that regions containing SSRs markers were found in the transcribed region of nine cashew genotypes, and can be a useful tool in genetic analysis and open up prospects for endogenous role of SSRs in protein function.

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