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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.
1

Building an episomal model of aging in saccharomyces cerevesiae

Falcon, Alaric Antonio, January 2004 (has links)
Thesis (Ph.D.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 117 pages. Includes Vita. Includes bibliographical references.
2

Characterization of unclassifiable acinetobacters from Hong Kong.

January 2001 (has links)
by Chu Ka-yi. / Thesis submitted in: October 2000. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 160-174). / Abstracts in English and Chinese. / ABSTRACT (English) --- p.i / ABSTRACT (Chinese) --- p.iii / ACKNOWLEDGMENT --- p.v / LIST OF CONTENTS --- p.vi / LIST OF TABLES --- p.x / LIST OF FIGURES --- p.xii / ABBREVIATIONS --- p.xiv / TERMS --- p.xv / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Taxonomy of Acinetobacter - historical and current --- p.1 / Chapter 1.2 --- Ecology and clinical significance of Acinetobacter --- p.5 / Chapter 1.3 --- General identification and typing methods for Acinetobacter species / Chapter 1.3.1 --- Identification at species level --- p.9 / Chapter 1.3.2 --- Identification at strain level --- p.11 / Chapter 1.4 --- Methods used in this study for characterization of Acinetobacter species / Chapter 1.4.1 --- Amplified ribosomal DNA restriction analysis (ARDRA) --- p.14 / Chapter 1.4.2 --- tDNA spacer fingerprinting (tDNA) --- p.15 / Chapter 1.4.3 --- Fluorescent amplified fragment length polymorphism (FAFLP) --- p.16 / Chapter 1.4.4 --- Phenotypic methods including carbon utilization tests --- p.20 / Chapter 1.5 --- Objectives --- p.25 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.27 / Chapter 2.1 --- Bacterial strains and isolates --- p.27 / Chapter 2.2 --- Materials / Chapter 2.2.1 --- Antimicrobial agents and chemicals --- p.30 / Chapter 2.2.2 --- "Carbohydrates, enzymes and other materials" --- p.32 / Chapter 2.2.3 --- Commercial media and media prepared manually --- p.33 / Chapter 2.2.4 --- "Buffers, solutions and list of instruments" --- p.35 / Chapter 2.3 --- General Bacteriological Techniques / Chapter 2.3.1 --- Isolation of acinetobacters --- p.38 / Chapter 2.3.2 --- Routine bacteriological identification --- p.39 / Chapter 2.4 --- General Molecular Biology Techniques / Chapter 2.4.1 --- DNA isolation --- p.40 / Chapter 2.4.2 --- Transformation --- p.41 / Chapter 2.4.3 --- Agarose gel electrophoresis --- p.43 / Chapter 2.5 --- Genospeciation of acinetobacters by Amplified Ribosomal Restriction DNA Analysis (ARDRA) --- p.44 / Chapter 2.6 --- Characterization of ARDRA unclassifiable acinetobacters (AUA) by Phenotypic methods / Chapter 2.6.1 --- Temperature tolerance tests --- p.47 / Chapter 2.6.2 --- Carbon utilization tests --- p.47 / Chapter 2.6.3 --- Gelatin and hemolysis tests --- p.48 / Chapter 2.6.4 --- Minimum Inhibitory Concentration (MIC) --- p.49 / Chapter 2.7 --- Characterization of AUA by tDNA spacer fingerprinting (tDNA) method --- p.51 / Chapter 2.8 --- Characterization of AUA by Fluorescent Amplified Fragment Length Polymorphism analysis (FAFLP) --- p.55 / Chapter 2.9 --- Relatedness study of isolates within the same AUA group by Enterobacterial Repetitive Intergenic Consensus (ERIC) typing method --- p.58 / Chapter CHAPTER 3 --- COLLECTION OF UNCLASSIFIABLE ACINETOBACTERS by ARDRA (AUA) METHOD --- p.59 / Chapter 3.1 --- Results / Chapter 3.1.1 --- Isolation and genospeciation of acinetobacters from hospital environments and raw food --- p.59 / Chapter 3.1.2 --- Collection of ARDRA unclassifiable acinetobacters (AUA) --- p.63 / Chapter 3.2 --- Discussion / Chapter 3.2.1 --- Limitations and merits of ARDRA method --- p.68 / Chapter 3.2.2 --- Potential significance of the representative AUA groups --- p.71 / Chapter CHAPTER 4 --- CHARACTERIZATION OF ARDRA UNCLASSIFIABLE ACINETOBACTERS (AUA) BY tDNA SPACER (tDNA) FINGERPRINTING METHOD --- p.72 / Chapter 4.1 --- Results / Chapter 4.1.1 --- Assessment of reproducibility --- p.72 / Chapter 4.1.2 --- Construction of the database with the reference strains --- p.75 / Chapter 4.1.3 --- Characterization of the representative AUA groups --- p.78 / Chapter 4.2 --- Discussion / Chapter 4.2.1 --- Evaluation of the reproducibility and discriminatory power --- p.89 / Chapter 4.2.2 --- Possible genospeciation of the representative AUA groups --- p.92 / Chapter 4.2.3 --- Limitations and merits --- p.96 / Chapter CHAPTER 5 --- CHARACTERIZATION OF ARDRA UNCLASSIFIABLE ACINETOBACTERS (AUA) BY FLUORESCENT AMPLIFIED FRAGMENT LENGTH POLYMORPHISM (FAFLP) METHOD --- p.98 / Chapter 5.1 --- Results / Chapter 5.1.1 --- Assessment of robustness and reproducibility --- p.98 / Chapter 5.1.2 --- Construction of the database with the reference strains --- p.104 / Chapter 5.1.2 --- Characterization of the representative AUA groups --- p.108 / Chapter 5.2 --- Discussion / Chapter 5.2.1 --- "Evaluation of robustness, reproducibility and discriminatory power" --- p.116 / Chapter 5.2.2 --- Possible genospeciation of the representative AUA groups --- p.120 / Chapter 5.2.3 --- Merits and limitations --- p.122 / Chapter CHAPTER 6 --- CHARACTERIZATION OF ARDRA UNCLASSIFABLE ACINETOBACTERS (AUA) BY PHENOTYPIC METHODS --- p.125 / Chapter 6.1 --- Results Characterization of the representative AUA groups --- p.125 / Chapter 6.2 --- Discussion / Chapter 6.2.1 --- Possible genospeciation of the representative AUA groups --- p.134 / Chapter 6.2.2 --- Limitations in classification of Acinetobacter species at genomic species level --- p.135 / Chapter CHAPTER 7 --- RELATEDNESS OF ISOLATES WITHIN THE SAME AUA GROUPS --- p.139 / Chapter 7.1 --- Results Typing results of the studied AUA groups by ERIC method --- p.139 / Chapter 7.2 --- Discussion Relatedness of the isolates within the same AUA group --- p.146 / Chapter CHAPTER 8 --- GENERAL DISCUSSION --- p.148 / Chapter 8.1 --- Possible genospeciation of the representative AUA groups --- p.150 / Chapter 8.2 --- "Comparison of ARDRA, tDNA fingerprinting, FAFLP and phenotypic methods" --- p.154 / Chapter 8.3 --- Conclusion and significance of the AUA groups studied --- p.158 / Chapter 8.4 --- Future work --- p.159 / REFERENCES --- p.160 / APPENDIX --- p.176
3

A comparative and mutational dissection of barriers to replication fork movement in the rDNA of yeast /

Ward, Teresa Rose, January 1996 (has links)
Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [115]-121).
4

Caracterização citogenética e molecular do DNAr 5S e sua forma variante de DNA satélite em espécies do grupo de Physalaemus cuvieri (Anura, Leptodactylidae) = Cytogenetic and molecular analysis of the 5S rDNA and its variant form of satellite DNA in Physalaemus cuvieri species group (Anura, Leptodactylidae) / Cytogenetic and molecular analysis of the 5S rDNA and its variant form of satellite DNA in Physalaemus cuvieri species group (Anura, Leptodactylidae)

Vittorazzi, Stenio Eder, 1984- 26 August 2018 (has links)
Orientadores: Shirlei Maria Recco Pimentel, Luciana Bolsoni Lourenço / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T06:02:48Z (GMT). No. of bitstreams: 1 Vittorazzi_StenioEder_D.pdf: 3469046 bytes, checksum: 548f412477dbed97bd45f19e26cea793 (MD5) Previous issue date: 2014 / Resumo: Os genomas dos eucariotos são ricos em sequências repetitivas, as quais compreendem sequências dispersas e em tandem. Entre as sequências em tandem, incluem-se os DNA satélites, os DNA ribossomais e cópias parálogas. Os DNA satélites são os principais constituintes da heterocromatina constitutiva e os genes ribossomais transcrevem os RNAr para compor os ribossomos, que dividem-se em duas famílias, DNAr 45S e 5S. Em um mesmo organismo, diferentes tipos de DNAr 5S já foram reconhecidos, mostrando a existência de uma diversidade quanto a esse tipo de sequência. No anuro Physalaemus cuvieri, uma forma de DNA satélite denominada PcP190 foi caracterizada e teve sua origem atribuída a uma derivação do DNAr 5S em uma espécie ancestral. Em diferentes populações de P. cuvieri estudadas previamente com as ferramentas da citogenética convencional, uma acentuada variação interpopulacional nos cromossomos portadores da NOR pôde ser observada, e nas demais espécies do grupo de P. cuvieri, peculiaridades interespecíficas foram evidenciadas, porém, os cariótipos entre essas espécies são muito semelhantes. O objetivo nessa tese foi ampliar o estudo citogenético de espécies do grupo de P. cuvieri que possuíam carência na descrição cromossômica, como P. kroyeri e P. cicada. Objetivou-se também analisar o DNA satélite PcP190 em nível cromossômico e molecular, assim como estudar a organização molecular e a diversidade de sequências do DNAr 5S no genoma das espécies de Physalaemus e espécies de gêneros relacionados. Com os resultados da pesquisa, três capítulos são apresentados, sendo eles: (i) "Long-time evolution and highly dynamic satellite DNA in leptodactylid and hylodid frogs", o qual mostra que o DNA satélite PcP190 é amplamente conservado e pode ser reconhecido em representantes de duas famílias de anuros, Leptodactylidae e Hylodidae; além disso, mostra também que essas sequências são altamente dinâmicas nos cromossomos das espécies do grupo de P. cuvieri. (ii) "Diversidade do DNAr 5S em Leiuperinae (Anura)", os resultados mostram que no genoma desses anuros existe uma diversidade dessa classe de família multigênica maior do que proposto até então, e que essas sequências do DNAr 5S permanecem conservadas desde a divergência evolutiva entre os Actinopterigio e Sarcopterigio. (iii) "Cariótipo e mapeamento de DNA repetitivo em Physalaemus kroyeri e P. cicada (Anura Leptodactylidae)", onde é apresentado que a banda 5p de P. kroyeri tem se mostrado um bom marcador cromossômico para as espécies do grupo de P. cuvieri, o que indica se tratar de uma sinapomorfia cromossômica. Contrariamente, a ausência dessa banda 5p em P. cicada não fornece evidência para a inclusão de P. cicada no grupo de P. cuvieri ou em qualquer outro grupo de espécies / Abstract: The genomes of eukaryotic organisms are rich in repetitive DNA sequences, which can be dispersed or arrayed in tandem. The tandem repeat sequences include the satellite DNA, the ribosomal DNA, and paralogous copies. Satellite DNA is the main component of constitutive heterochromatin, while the ribosomal genes encode the rRNAs that make up the ribosomes; they are divided into two families, the 45S and 5S rRNA. Different types of 5S rDNA have been identified in a single organism, proving that there is diversity in this type of DNA sequence. In the anuran Physalaemus cuvieri, a satellite DNA family called PcP190 has been identified, which is thought to have derived from the 5S rDNA of an ancestor species. In different populations of P. cuvieri that were previously studied with conventional cytogenetic tools, an accentuated interpopulational variation among chromosomes harboring the NOR was observed, while in other species of the P. cuvieri group, interspecific traits were found. However, the karyotypes in these species are very similar. The aim of this thesis was to expand the cytogenetic studies on P. cuvieri species that needed further chromosomal description, such as P. kroyeri and P. cicada. Another objective was to analyze the PcP190 satellite DNA at the chromosomal and molecular level, as well as to study the molecular organization and the diversity of 5S rDNA sequences in the genomes of the Physalaemus species and other species of related genera. We present three chapters as a result of this research: (i) "Long-time evolution and highly dynamic satellite DNA in frogs," which demonstrates that the PcP190 satellite DNA is widely conserved and was recognized in representatives of two anurans families, Leptodactylidae and Hylodidae. Moreover, it also demonstrates that these sequences are highly dynamic within the chromosomes of the P. cuvieri species group. (ii) "5S rDNA in Leiuperinae (Anura): new insights on its evolution." The results show that in the genomes of these anurans there is wider diversity among this multigenic family than previously assumed and that these 5S rDNA sequences have remained conserved since the evolutionary divergence of Actinopterygii and Sarcopterygii. (iii) "Karyotype and repetitive DNA mapping of the Physalaemus kroyeri and P. cicada (Anura Leptodactylidae)," which demonstrates that the 5p chromosomal band of P. kroyeri is a good chromosomal marker for species from the P. cuvieri group, indicating that it is a chromosomal synapomorphy. Conversely, the absence of this 5p band in P. cicada does not provide evidence for the inclusion of this species in the P. cuvieri group or any other species group / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural
5

Paternal Effects on Metabolism in Mammals: A Dissertation

Shea, Jeremy M. 19 March 2015 (has links)
The following work demonstrates that paternal diet controls medically important metabolic phenotypes in offspring. We observe transmission of dietary information to the zygote via sperm, and this information evades reprogramming that typically occurs after fertilization. Cytosine methylation is implicated as a major contributor to meiotic epigenetic inheritance in several transgenerational phenomena. Our extensive characterization of the sperm methylome reveals that diet does not significantly affect methylation patterns. However, we find that extensive epivariability in the sperm epigenome makes important contributions to offspring variation. Importantly, coordinate cytosine methylation and copy number changes over the ribosomal DNA locus contributes to variation in offspring metabolism. Thus, rDNA variability acts independently of postadolescent paternal diet to influence offspring metabolism. Therefore, at least two mechanisms exist for epigenetically controlling offspring metabolism: stochastic epivariation and diet acting by an unknown mechanism to further modulate metabolism. This work argues that an offspring's phenotype can no longer be viewed solely as the result of genetic interactions with the developmental environment - the additional influences of paternal environment and inherited epigenetic variability must also be considered. These findings reveal novel contributions to metabolism that could revolutionize how we think about the risk factors for human health and disease.
6

Polimorfismo dos genes mitocondrial 16S rRNA e nuclear ITS-2 em populações de Biomphalaria tenagophilada bacia litorânea do estado de São Paulo e estudo da suscetibilidade dos caramujos ao Schistosoma mansoni / DNA polymorphism within 16S rRNA and ITS-2 genes of Biomphalaria tenagophilafrom coastal basin at São Paulo state Brazil and implications to infection by strains of Schistosoma mansoni

Palasio, Raquel Gardini Sanches, 1985- 23 August 2018 (has links)
Orientadores: Eliana Maria Zanotti Magalhães, Roseli Tuan / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T20:56:19Z (GMT). No. of bitstreams: 1 Palasio_RaquelGardiniSanches_M.pdf: 32439761 bytes, checksum: e30767ddf6f947a1346867f1f0a27494 (MD5) Previous issue date: 2013 / Resumo: O planorbídeo Biomphalaria tenagophila (Orbigny, 1835) (Gastropoda: Planorbidae) é a espécie hospedeira intermediaria do Schistosoma mansoni Sambon, 1907 predominante no estado de São Paulo. No estado de São Paulo a espécie está relacionada com a transmissão da maioria dos casos autóctones de esquistossomose. Exemplares de B. tenagophila provenientes de várias localidades da bacia Litorânea Paulista foram analisados quanto ao polimorfismo de um trecho do gene mitocondrial rRNA16S e o segmento ITS2 que integra o cistron de DNA ribossômico nuclear. Paralelamente foi testada a suscetibilidade de populações de B. tenagophila das localidades de Itariri, Caraguatatuba, Ilha Bela e São Sebastião com linhagens diferenciadas de S. mansoni. As localidades amostradas representam pontos importantes na transmissão da esquistossomose no estado de São Paulo, devido as condições de infraestrutura, por serem áreas inundáveis e pela presença de contingente humano de outras áreas do Brasil. Nesta situação, destacam-se o município de Itariri, onde ocorreram os maiores números de casos de esquistossomose no Vale do Ribeira e os municípios de Caraguatatuba e São Sebastião que ao longo dos anos vem tendo um aumento no número de casos autóctones. Do total de 1635 espécimes de Biomphalaria coletados nas coleções de água doce do Litoral Norte e Sul do estado de São Paulo observamos a predominância de 84% da espécie B. tenagophila e 16% da espécie Biomphalaria straminea (Dunker, 1848). As análises moleculares indicaram que existem duas subpopulações de B. tenagophila nesta área, com haplótipos exclusivos para Juquiá e Registro, e sequências que compartilham o mesmo haplótipo do Litoral Norte e de Itariri. As taxas de infecções para as linhagens SJ e SJS mostraram que os caramujos do Litoral Norte foram mais suscetíveis que os caramujos do município de Itariri, talvez pode ser devido a proximidade dos municípios do Litoral Norte com o Vale do Rio Paraíba, local de origem da linhagem. A maior taxa de infecção correspondeu uma maior mortalidade nos moluscos de Caraguatatuba e Ilha Bela, indicando que o parasita afetou a sobrevida dos moluscos. Os resultados deste trabalho mostraram que todas as populações testadas foram resistentes às linhagens BH e SE. Os resultados sugerem haver uma correlação positiva entre a suscetibilidade ao S. mansoni e a redução da variabilidade genética nas populações de caramujos testadas. Desta forma, o risco de infecção dos hospedeiros intermediários por S. mansoni estaria relacionado com populações de caramujos geneticamente homogêneas. Desta forma o grau de diversidade genética pode ser um indicador de risco para a transmissão da esquistossomose / Abstract: The planorbid Biomphalaria tenagophila (Orbigny, 1835) (Gastropoda: Planorbidae) is the predominant intermediate host specie of Schistosoma mansoni Sambon, 1907 in São Paulo state, where is most related to autochthonous cases of schistosomiasis transmission. Specimens of B. tenagophila were obtained from several locations of São Paulo Coastal Basin and analyzed for the polymorphism of a portion of the mitochondrial gene rRNA16S and the ITS2 segment, wich integrates the cistron of nuclear ribosomal DNA. In parallel it was tested the susceptibility of B. tenagophila populations from the municipalities of Itariri, Caraguatatuba, Ilha Bela and São Sebastião, with different strains of S. mansoni. These sampling sites represent important points of schistosomiasis transmission in São Paulo state due to infrastructure conditions, floodable areas and the presence of human contingent of other Brazilian areas, in particular the municipality of Itariri, where occurred the highest number of cases of schistosomiasis in the Ribeira Valley and in the cities of São Sebastião and Caraguatatuba that over the years it has had an increase in the number of autochthonous cases. Of the total 1635 of Biomphalaria specimens collected in freshwater pools from the North and South Coasts of the state of São Paulo, it was observed the predominance of 84% B.tenagophila species and the presence of Biomphalaria straminea (Dunker, 1848) in 16%. The molecular analysis indicates that there are two subpopulations of B. tenagophila in this area, one with an exclusive and unique haplotype from Juquiá and Registro, and the other with sequences which share the same haplotype from the North Coast and Itariri. The infection rates of SJ and SJS strains show the snails from the North Coast are more susceptible than the snails from the municipality of Itariri. This, in hypothesis, can be caused due to the proximity of the cities of the North Coast and the Paraíba River Valley, site of origin of those strains. The highest infection rate corresponded to a higher mortality rate of the mollusks from Caraguatatuba and Ilha Bela, indicating the effect of the parasite in the snails' survival. The results of this study show that all tested populations were resistant to the BH and SE strains. The results suggest a positive relationship between S. mansoni susceptibility and the reduction of genetic variability in the snails populations tested. Therefore, the S. mansoni infection risk of the intermediate hosts would be related to genetically homogeneous snails' populations. And with that, genetic diversity can be an indicator of risk for the transmission of schistosomiasis / Mestrado / Biodiversidade Animal / Mestra em Biologia Animal
7

Análise genético-evolutivas em espécies da família Calliphoridae (Diptera:Brachycera:Calyptratae) / Genetic and evolutionary analysis in species of the family Calliphoridae (Diptera: Brachycera: Calyptratae)

Marinho, Marco Antonio Tonus, 1984- 19 August 2018 (has links)
Orientadores: Ana Maria Lima de Azeredo-Espin, Nilson Ivo Tonin Zanchin / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T22:51:23Z (GMT). No. of bitstreams: 1 Marinho_MarcoAntonioTonus_D.pdf: 17816653 bytes, checksum: e915a871c22b7741c1be765f87c95ff5 (MD5) Previous issue date: 2011 / Resumo: A superfamília Oestroidea (Diptera:Brachycera:Calyptratae), com +13.000 espécies descritas, compreende um dos grupos mais numerosos e ecologicamente diversos da ordem Diptera. O grupo possui grande interesse para atividades humanas por englobar espécies de importância médica, veterinária e forense, muitas das quais compõem a família Calliphoridae. Apesar do grande número de estudos disponíveis, as relações evolutivas no grupo, o qual é composto predominantemente por linhagens de rápida diversificação e radiação, ainda são controversas e pouco compreendidas, encorajando a caracterização de novos marcadores moleculares para análises de filogenia molecular. Neste contexto, esta tese foi desenvolvida e organizada em três capítulos descrevendo estudos genéticoevolutivos em espécies da superfamília Oestroidea, com ênfase em Calliphoridae. O primeiro capítulo trata da caracterização e avaliação do segundo espaçador transcrito interno (ITS2) do DNA ribossomal como um marcador molecular para análises filogenéticas em Calliphoridae, incorporando informações tanto da sequência primária quanto da estrutura secundária adquirida pela região. A análise do ITS2 revelou um padrão hierarquicamente organizado das distâncias genéticas nos níveis de espécies, gêneros e subfamílias, enquanto pouca variação intra-específica foi encontrada. As árvores inferidas recuperaram muitas das relações comumente aceitas entre os táxons amostrados, sendo que a inclusão da informação estrutural nas análises resultou na recuperação de topologias mais confiáveis. Sendo assim, o potencial da região ITS2 como um marcador molecular para análises evolutivas na família Calliphoridae foi confirmado e seu uso em análises de maior escala, incluindo marcadores de diferentes naturezas de evolução, encorajado. O segundo capítulo da tese descreve a caracterização in vitro da estrutura secundária adquirida pelo ITS2, através de padrões de digestão enzimática e análise dos fragmentos gerados, em espécies representantes das três superfamílias de Calyptratae: Glossina morsitans, Musca domestica e Cochliomyia hominivorax. A análise do padrão de fragmentos gerados pelas enzimas RNAse I, A, T1 e V1, quando mapeados na estrutura secundária predita in silico, corroborou muitos dos domínios inicialmente preditos pelo método computacional, ressaltando a importância e confiabilidade desses métodos na predição de estruturas secundárias. O terceiro capítulo da tese descreve análises de filogenia molecular na superfamília Oestroidea, com ênfase na amostragem de espécies de Calliphoridae, utilizando quatro marcadores moleculares, dois nucleares (ITS2 e 28S) e dois mitocondriais (COI e 16). As análises, que incluíram uma extensa avaliação dos efeitos de diferentes estratégias de particionamento dos dados em análises de inferência Bayesiana (por conformação estrutural e posição no códon), revelaram a existência de dois clados principais em Oestroidea: Tachinidae + Mesembrinellinae e Oestridae + Rhiniinae + Sarcophagidae + Calliphoridae (definida em senso estrito). O status de família recentemente atribuído à Rhiniinae foi encontrado, enquanto há também evidências para sugerir o mesmo para a subfamília Mesembrinellinae, como proposto anteriormente por outros autores. As diferentes estratégias de particionamento do conjunto de dados amostrados resultaram em diferenças discretas em termos de topologia, comprimentos de ramo e suporte geral das filogenias inferidas. Embora o resultado geral indique uma melhor resolução das análises quando do uso de combinações de partições e modelos mais complexas, as mesmas podem ocasionar também um aumento considerável na incerteza associada às análises / Abstract: The Oestroidea superfamily (Diptera: Brachycera: Calyptratae), with +13,000 described species, comprises one of the most numerous and ecologically diverse groups in the Diptera order. The group is actually of great interest for human activities since it includes species of medical, veterinary and forensic importance, most of them included in the Calliphoridae family. Despite the existence of several studies addressing the issue, evolutionary relationships in Oestroidea, a group mainly composed of rapidly diverged lineages, remains contentious and poorly understood, encouraging the characterization of new molecular markers for phylogenetic inference analyses. In this context, this thesis was developed and organized in three chapters describing genetic and evolutionary studies in species of the Oestroidea superfamily, with emphasis in Calliphoridae. The first chapter deals with the characterization and evaluation of the second internal transcribed spacer region (ITS2) of the ribosomal DNA cluster as a molecular marker for phylogenetic inference in Calliphoridae, including information of both primary sequence and secondary structure. The analyses revealed an hierarchically organized pattern of genetic distances in the specific, generic and subfamilial level, while little intraspecific variation was detected. Inferred trees were able to recover most of the commonly accepted relationships among the sampled taxa, with the consideration of structural information resulting in better supported topologies. Thereby, the potential of the ITS2 region as a molecular marker for phylogenetic inference in the Calliphoridae family was corroborated and its use in larger scale analyses, including other markers with different evolutionary patterns, encouraged. Chapter II describes the in vitro characterization of the secondary structure of the ITS2 region, through patterns of enzymatic digestion and analysis of the generated fragments, in representative species of the three superfamilies of the Calyptratae clade: Glossina morsitans, Musca domestica and Cochliomyia hominivorax. Analyses of the patterns of the fragments generated by enzymatic digestions with the RNAses I, A, T1 and V1, when mapped in the in silico predicted secondary structure, corroborated the folding of most of the domains predicted by computational methods, highlighting the importance and reliability of these methods in secondary structure prediction. Chapter III describes molecular phylogenetic analyses in the Oestroidea superfamily, with emphasis on the Calliphoridae family, using four different molecular markers, two nuclear (ITS2 and 28S) and two mitochondrial (COI and 16S) regions. The analyses, which included a comprehensive evaluation of the effects of different data partitioning strategies in a Bayesian framework (by structural conformation and codon position), revealed the existence of two main clades in Oestroidea: Tachinidae+Mesembrinellinae and Oestridae+Rhiniinae+Sarcophagidae+Calliphoridae (defined in a strict sense). The recently attributed family status to Rhiniinae was confirmed, and there are evidence to also suggest the same for Mesembrinellinae, as previously pointed out by other studies. The different data partitioning strategies used in the sampled dataset resulted in small differences in terms of inferred topologies, estimated branch lengths and average support. Although the overall results indicate a significant increase in phylogeny resolution when more complex and parameter-rich models / partitions combinations are used, they can also lead to an increased uncertainty in the phylogenetic estimation process / Doutorado / Genetica Animal e Evolução / Soutor em Genética e Biologia Molecular
8

Contribution à l'étude des Psychodopygina d'Equateur (Diptera, Psychodidae, Phlebotominae) : Biologie et systématique. / Molecular systematics and Biology of Psychodopygina (Diptera, Psychodidae, Phlebotominae) from Ecuador.

Zapata, Sonia 09 July 2012 (has links)
Des prospections réalisées en Equateur (Amazonie et côte pacifique) ont permis la collecte d'un matériel entomologique abondant et diversifié, notamment chez les Psychodopygina. Nos travaux ont permis de réaliser plusieurs travaux de systématique, essentiellement moléculaire. Afin de tester les hypothèses phylogénétiques développées par Galati (2010), nous avons conduit une étude de phylogénie moléculaire chez les Psychodopygina. Basée sur les séquences des domaines D1, C2 et D2 de l'ADNr 28S et sur celles d'une partie du cytochrome b de l'ADNmt, elle inclut 49 espèces représentant les sept genres de la sous tribu et la majorité des sous-genres et séries. Les marqueurs ribosomiques sont mieux adaptés à la problématique que le marqueur mitochondrial. Le genre Psychodopygus est monophylétique. En raison du positionnement de Ny. richardwardi parmi les Trichophoromyia, nous concluons à la paraphylie des genres Nyssomyia et Trichophoromyia. Le genre Psathyromyia est également paraphylétique, tout comme le genre Martinsmyia. Le genre Bichromomyia serait le groupe frère du genre Psychodopygus et la validité du genre Vianniamyia, inclus dans le genre Psathyromyia doit être discutée. Des phylogénies moléculaires plus terminales ont été réalisées par comparaison de séquences de l'ITS2, de l'EF-1α et du cytochrome b.Chez les Psychodopygus de la série Guyanensis, une étude moléculaire couplée à une étude morphologique et morphométrique de morphotypes différents chez Ps. geniculatus, en sympatrie avec Ps. corossoniensis et Ps. luisleoni nous a conduit à décrire une espèce nouvelle pour la science : Ps. francoisleponti.Chez Pa. aragaoi, notre étude pilote basée sur l'analyse de morphotypes différents allopatriques et sympatriques renforce l'hypothèse de l'existence probable d'un complexe d'espèces chez ce taxon. Chez Ny. trapidoi, les analyses moléculaires et enzymatiques conduites sur des exemplaires clairs et foncés ne supportent pas la mise en évidence de deux populations comme cela avait été auparavant démontré. Nos approches épidémiologiques ont permis de mettre en évidence l'ADN d'Endotrypanum monterogeii chez plusieurs exemplaires de Ny. trapidoi. Si aucun phlebovirus n'a été détecté dans les échantillons étudiés, nous rapportons la présence d'un flavivirus chez Pa. abonnenci. Mots-clés: Psychodopygina, Equateur, ADN ribosomique, ADN mitochondrial, phylogénie, Endotrypanum. / Most Ecuadorian sand flies studied so far belong to Psychodopygina sub tribe and the present research uses morphometric and modern molecular techniques to answer many some questions regarding this taxon in Ecuador. We present phenetic and phylogenetic analyses based on the sequences of the domains D1, C2 and D2 of the 28S rDNA and cytochrome b mtDNA were used to test the classification of Psychodopygina sub tribe proposed by Galati (2010). Our study includes 49 species representing the seven genera included in the sub tribe and its main subgenera and series. The results support the monophyly of the genus Psychodopygus. The genera Psathyromyia, Nyssomyia and Trichophoromyia are paraphyletic. Bichromomyia is the sister group of Psychodopygus and the validity of the genus Viannamyia is doubtful because it is included inside the Psathyromyia genus. Our data strongly suggest the presence of two populations within Ps. geniculatus and the lack of intermediate forms between these two morphotypes incited us to describe a new sympatric species, Psychodopygus francoisleponti.We also carried out a pilot study based on the analysis of different allopatric and sympatric morphotypes of Pa. aragaoi which suggested the existence of a possible complex of species in this taxa.Finally, we analyzed of mitochondrial gene sequences and isoenzymes from Ny. trapidoi collecte from Ecuador and our result did not support the existence of two sibling species within as previously reported in the literature. From an epidemiological point of view, we emphasize the probable vectorial role of Nyssomyia trapidoi for Endotrypanum monterogeii. Moreover, no phlebovirus was detected in the processed sand flies whereas a flavivirus has been found in a pool of Psathyromyia. abonnenci females.Key words: Psychodopygina, Ecuador, ribosomal DNA, mitochondrial DNA, phylogeny, Endotrypanum.
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Estudos moleculares de Anopheles albitarsis e Anopheles triannulatus (Diptera: Culicidae) capturados em criadouro na planície de inundação do Mato Grosso do Sul, Brasil / Molecular studies of Anopheles albitarsis and Anopheles triannulatus (Diptera: Culicidae) captured in flood plain breeding sites in Mato Grosso do Sul, Brazil

Neves, Amanda 27 January 2010 (has links)
A malária é uma doença grave, cujos vetores são mosquitos do gênero Anopheles. Esse gênero é composto por cerca de 500 espécies e aproximadamente 45 são responsáveis pela transmissão do parasito em todo o mundo. Alguns destes vetores são componentes de complexo de espécies crípticas como Complexo Albitarsis e Complexo Triannulatus. O Complexo Albitarsis é formado por quatro espécies: An. albitarsis s.s, An. albitarsis B, An. marajoara e An. deaneorum. O Complexo Triannulatus é composto por três espécies: An. triannulatus, An. halophylus e An. triannulatus C. Algumas técnicas moleculares são utilizadas para auxiliar na distinção destas espécies crípticas. Dessa forma, DNA de An. albitarsis s.l e An. triannulatus s.l., capturados na Usina de Porto Primavera, foram amplificados para ITS2 e para o gene ND4 do DNAmt. Todas as amostras foram submetidas à técnica de RFLP. Algumas amostras foram seqüenciadas diretamente ou clonadas para posterior seqüenciamento a fim de se confirmar a espécie. Das amostras do Complexo Albitarsis, 62,85% foram identificadas como An. deaneorum para ITS2-RFLP. As restantes foram amplificadas para ND4-RFLP e foram identificadas como An. albitarsis s.s. Observou-se, no entanto, que as amostras do Complexo Albitarsis não exibiram similaridade total com as depositadas no GeneBank sendo que para ITS2-PCR estas foram identificadas como An. albitarsis s.s. e An. deaneorum, enquanto que para o gene ND4 todas foram identificadas como An. albitarsis B. O ITS2-RFLP para o An. triannulatus s.l demonstrou polimorfismos entre as espécies. No seqüenciamento, estas amostras foram similares àquelas depositadas no GeneBank. O emprego de marcadores moleculares podem, em parte, auxiliar na distinção de espécies crípticas, porém outros marcadores devem ser avaliados a fim de se elucidar a identificação do Complexo Albitarsis. / Malaria is a severe disease whose vectors are mosquitoes belonging to the genus Anopheles. This genus contains 500 species of which approximately 45 are responsible for the worldwide transmission of these parasites. Some of these vectors belong to cryptic species such as those of the Albitarsis and Triannulatus Complex. The Albitarsis Complex is composed of four species: An. albitarsis s.s., An. albitarsis B, An. marajoara and An. deaneorum. The Triannulatus Complex contains three species: An. triannulatus, An. halophylus and An. triannulatus C. We used molecular techniques to differentiate these cryptic species. Thus, DNA of An. albitarsis s.l and An. triannulatus s.l, captured at the Porto Primavera Dam had their ITS2 and their mtDNA, ND4 genes amplified. All samples were analyzed by the RFLP technique. Some samples were directly sequenced while others were cloned for subsequent sequencing for species confirmation. Within the Albitarsis Complex, 62.85% were identified as An. deaneorum by RFLP-ITS2. The remaining were amplified by RFLP-ND4 and identified as An. albitarsis s.s. However the results of sequencing of the samples of the Albitarsis Complex did not overlap entirely with those deposited in the GeneBank since those amplified by RFLP-ITS2 were identified as An. albitarsis s.s. and An. deaneorum while those obtained by RFLP-ND4 were identified as An. albitarsis B. Also RFLP-ITS2 of A. triannulatus s.l. contained polymorphic regions among different species. By sequencing, these samples were similar to those deposited in the GeneBank. The use of molecular markers did, in some instances help to distinguish species within cryptic complexes, however other markers need to be evaluated to elucidate further identification of the Albitarsis Complex.
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Estudos moleculares de Anopheles albitarsis e Anopheles triannulatus (Diptera: Culicidae) capturados em criadouro na planície de inundação do Mato Grosso do Sul, Brasil / Molecular studies of Anopheles albitarsis and Anopheles triannulatus (Diptera: Culicidae) captured in flood plain breeding sites in Mato Grosso do Sul, Brazil

Amanda Neves 27 January 2010 (has links)
A malária é uma doença grave, cujos vetores são mosquitos do gênero Anopheles. Esse gênero é composto por cerca de 500 espécies e aproximadamente 45 são responsáveis pela transmissão do parasito em todo o mundo. Alguns destes vetores são componentes de complexo de espécies crípticas como Complexo Albitarsis e Complexo Triannulatus. O Complexo Albitarsis é formado por quatro espécies: An. albitarsis s.s, An. albitarsis B, An. marajoara e An. deaneorum. O Complexo Triannulatus é composto por três espécies: An. triannulatus, An. halophylus e An. triannulatus C. Algumas técnicas moleculares são utilizadas para auxiliar na distinção destas espécies crípticas. Dessa forma, DNA de An. albitarsis s.l e An. triannulatus s.l., capturados na Usina de Porto Primavera, foram amplificados para ITS2 e para o gene ND4 do DNAmt. Todas as amostras foram submetidas à técnica de RFLP. Algumas amostras foram seqüenciadas diretamente ou clonadas para posterior seqüenciamento a fim de se confirmar a espécie. Das amostras do Complexo Albitarsis, 62,85% foram identificadas como An. deaneorum para ITS2-RFLP. As restantes foram amplificadas para ND4-RFLP e foram identificadas como An. albitarsis s.s. Observou-se, no entanto, que as amostras do Complexo Albitarsis não exibiram similaridade total com as depositadas no GeneBank sendo que para ITS2-PCR estas foram identificadas como An. albitarsis s.s. e An. deaneorum, enquanto que para o gene ND4 todas foram identificadas como An. albitarsis B. O ITS2-RFLP para o An. triannulatus s.l demonstrou polimorfismos entre as espécies. No seqüenciamento, estas amostras foram similares àquelas depositadas no GeneBank. O emprego de marcadores moleculares podem, em parte, auxiliar na distinção de espécies crípticas, porém outros marcadores devem ser avaliados a fim de se elucidar a identificação do Complexo Albitarsis. / Malaria is a severe disease whose vectors are mosquitoes belonging to the genus Anopheles. This genus contains 500 species of which approximately 45 are responsible for the worldwide transmission of these parasites. Some of these vectors belong to cryptic species such as those of the Albitarsis and Triannulatus Complex. The Albitarsis Complex is composed of four species: An. albitarsis s.s., An. albitarsis B, An. marajoara and An. deaneorum. The Triannulatus Complex contains three species: An. triannulatus, An. halophylus and An. triannulatus C. We used molecular techniques to differentiate these cryptic species. Thus, DNA of An. albitarsis s.l and An. triannulatus s.l, captured at the Porto Primavera Dam had their ITS2 and their mtDNA, ND4 genes amplified. All samples were analyzed by the RFLP technique. Some samples were directly sequenced while others were cloned for subsequent sequencing for species confirmation. Within the Albitarsis Complex, 62.85% were identified as An. deaneorum by RFLP-ITS2. The remaining were amplified by RFLP-ND4 and identified as An. albitarsis s.s. However the results of sequencing of the samples of the Albitarsis Complex did not overlap entirely with those deposited in the GeneBank since those amplified by RFLP-ITS2 were identified as An. albitarsis s.s. and An. deaneorum while those obtained by RFLP-ND4 were identified as An. albitarsis B. Also RFLP-ITS2 of A. triannulatus s.l. contained polymorphic regions among different species. By sequencing, these samples were similar to those deposited in the GeneBank. The use of molecular markers did, in some instances help to distinguish species within cryptic complexes, however other markers need to be evaluated to elucidate further identification of the Albitarsis Complex.

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