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Adipositas ist eine polymorphe chronische Erkrankung mit epidemischer Prävalenz. Im katabolen Leptin-Melanocortin-Signalweg ist das Proopiomelanocortin Gen (POMC) ein zentrales Element, das bei Dysfunktion massive Adipositas bewirken kann. Auch eine kürzlich identifizierte intragenische Methylierungsvariante des POMC wurde mit Adipositas assoziiert und deutet somit auf eine mögliche epigenetische Modulation des Gewichtsphänotyps hin. Zur Aufklärung der Relevanz, Stabilität und Entwicklung dieser epigenetischen Modifikation wurden die Funktionalität, Ontogenese und Phylogenese der POMC DNA-Methylierung untersucht. In vitro Analysen zeigten DNA-Methylierungsabhängige Promoteraktivität beider CpG-Inseln (CGIs) des POMC. Diese hier erstmals beschriebene Transkriptionsaktivität der intragenischen CGI weist auf einen alternativen Promoter des POMC hin. Hinsichtlich der Ontogenese konnten in Mensch und Maus postnatal stabile DNA-Methylierungsmuster mit interindividueller Konservierung für beide CGIs des POMC identifiziert werden. Zusätzlich erwiesen sich Gewebeunabhängigkeit der DNA-Methylierungsmuster und ihre pränatale Ausbildung zwischen dem Blastocystenstadium und der frühen Organogenese in der Maus. Die POMC DNA-Methylierungsmuster upstream des Exon3 unterscheiden sich in Mensch und Maus. Der mögliche Einfluss von primatenspezifischen Alu-Elementen im Intron2 des POMC hierauf wurde in verschiedenen Primatenfamilien analysiert. Die Ergebnisse zeigen eine bedingte Assoziation der Alu-Elemente mit der DNA-Methylierung in der entsprechenden Region, lassen jedoch auch weitere Einflussfaktoren vermuten. Insgesamt zeigt diese Arbeit, dass die POMC DNA-Methylierung artspezifisch konserviert ist und in der frühen Embryogenese, vermutlich Alu-abhängig, ausgebildet wird. Dabei könnten stochastische Variationen der DNA-Methylierung die POMC-Aktivität beeinflussen und somit das Risiko für Adipositas erhöhen. / Obesity is a polymorphic chronic disease with epidemic prevalence. Within the catabolic leptin-melanocortin signaling pathway pre-proopiomelanocortin (POMC) is a pivotal element. Dysfunction of POMC, e.g. due to mutations, can cause severe obesity. Moreover, a recently identified intragenic methylation variant of POMC was found to be associated with obesity. Therefore, this indicates potential epigenetic modulation of the weight phenotype. To gain further insight into the relevance, stability, and origin of this epigenetic modification, the functionality, ontogenesis, and phylogenesis of the POMC DNA methylation patterns were analyzed. In vitro analyses revealed DNA methylation-dependent promoter activity of both CpG islands (CGIs) of POMC. Thereby, the intragenic CGI was identified as a potential alternative promoter of POMC, which has not been described before. Regarding the ontogenesis, postnatally stable POMC DNA methylation patterns with interindividual conservation were detected for both CGIs in humans and mice. In addition, it was observed that the POMC DNA methylation patterns are non-tissue-specific, stable upon long time administration of a high fat diet, and develop prenatally between the blastocystal stage and the early organogenesis. The POMC DNA methylation pattern upstream of exon3 differs in humans and mice. A possible influence of primate-specific Alu elements within the intron2 region of POMC was analyzed in various primate families. Results evince a partial association of the Alu elements with the DNA methylation pattern in this particular region, but also suggest an influence of additional factors. Overall, this work demonstrates that DNA methylation of the POMC locus is species-specific highly conserved, and that it is established during early embryogenesis, possibly Alu-triggered. In the course of this, stochastic variances of the POMC DNA methylation might influence the POMC activity and consequently alter the risk to develop obesity.

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The study of lateralisation has taken several forms ranging from investigating morphological asymmetries to research on lateralised motor and perceptual functions with many studies successfully evidencing lateralisation in a variety of species. This study, featuring three species (olive baboons, rhesus macaques, and spotted hyaenas) investigated visual field biases with the aim of determining whether emotional valence underpins these biases whilst also considering the influence of a number of other factors such as emotional intensity, age, sex, rank, and, for the first time, oestrus cycles (olive baboons only). This study aimed to establish whether Campbell’s (1982) Right Hemisphere Hypothesis or Silberman & Weingartner’s (1986) Valence Hypothesis offered the more valid theory for the lateralisation of emotion by considering interactions across the full spectrum of emotion – a question the almost exclusive investigation of negatively affective scenarios by previous studies has been unable to answer. Furthermore, this study provided a new methodology for investigating behavioural lateralisation by suggesting that separating the visual spectrum into five fields (extreme left, mid left, centre, mid right and extreme right) allows a more accurate insight into the lateralisation of visual perception than the traditional hemifield model. Finally, a more conservative method is proposed for analysing behavioural data in future studies from this field and suggests that these methods provide a more accurate representation of the lateralisation of emotion than those previously employed. A population-level left side bias was found for the spotted hyaenas, thus providing the first evidence of significantly lateralised behaviour in a large carnivore and, for this species at least, lending some support to Campbell’s (1982) Right Hemisphere hypothesis but as population-level biases were not found for either of the other species it may be premature to suggest this support is unequivocal. Significant age effects were found in two species as adult olive baboons and spotted hyaenas were both found to express significant left side biases. Spotted hyaenas were also found to express significant left side biases for females, dominant individuals, high intensity interactions, and sexual valence interactions whilst olive baboons expressed a significant left side bias during negative valence behaviours but no significant lateral biases were found in any context for rhesus macaques. In olive baboons behaviours performed by males and those of a low intensity were found to occur more frequently in the mid and central visual fields and neutral valence behaviours were less occurrent in the extreme visual fields whilst in spotted hyaenas sexual, positive and negative valence behaviours were significantly less centralised than neutral valence behaviours. Non-oestrus adult female olive baboons were significantly more strongly lateralised than in-oestrus females, thus suggesting an influence of sex hormones upon lateralisation that may also have been apparent from the hyaena data, particularly regarding the significant lateral biases observed for females and dominant individuals. Finally, this thesis discusses a number of methodological issues that were encountered during this study and provides recommendations for future research in this field. Namely, this thesis provides an updated method for calculating laterality bias that is much more suitable for species with binocular vision and details a novel method of assessing visual field preferences by considering central and peripheral visual fields as separate entities. Furthermore, this thesis suggests that the weighted method designed and implemented for this study provides a much more accurate methodological foundation for analyses which avoids the caveats that may have affected previous research and thus provides a considerably more robust template that should be encouraged for any similar subsequent studies.

Els treballs realitzats en aquesta tesi tenen com objectius l'aplicació de la sistemàtica molecular i la filogeografia per resoldre relacions filogenètiques, clarificar la taxonomia i descriure la història de les poblacions de les espècies incloses dins de dos grups de mamífers d'elevat interés conservacionista: els mustélids (família Mustelidae) i els macacs (génere Macaca).L'ús de diferents marcadors genétics mitocondrials (el gen citocrom b i la regió control) i un de nuclear (les seqüencies flanquejants d'una regió repetitiva) ha permés reconstruir les relacions filogenètiques entre 33 espècies de mustelids; delimitar quatre grups filogeogràfics en el teixò euroasiàtic (Meles meles); detectar la venta de productes derivats d'aquesta espècie en països on està protegida; i estudiar el procès d'especiació del macac japonès (Macaca fuscata). A partir dels resultats obtinguts també s'han proposat canvis en la taxonomia d'aquests grups. Al final de la tesi es fan reflexions sobre el paper que desenvolupen els marcadors moleculars en la sistemàtica, sobre com classificar aquelles espècies que no ha finalitzat els seus processos d'especiació i sobre les aplicacions de la sistemàtica, la biologia evolutiva i la genètica en la conservació de la biodiversitat. / The objectives of this thesis were the application of molecular systematics and phylogeography to resolve phylogeny, to clarify taxonomy and to study the population history of species included within two groups of mammals of high conservation interest: the mustelids (Family Mustelidae) and the macaques (Genus Macaca).Using different mitochondrial (cytochrome b gene and control region) and nuclear (flanking sequences of a repetitive region) markers, we have been able to reconstruct the phylogeny of 33 mustelid species; to delimit four phylogeographic groups in the Eurasian badger (Meles meles); to detect the trade of Eurasian badger products in countries where this species is protected; and to study the speciation process of the Japanese macaque (Macaca fuscata). According to our results we have also proposed taxonomic changes in these groups.At the end of the thesis, there are also some reflections about the role of genetic markers in systematics; about how to classify the species that have not finished their speciation process; and about the application of systematics, evolutionary biology and genetics in conservation biology.

Submitted by Anderson Silva (avargas@icict.fiocruz.br) on 2012-09-25T11:49:38Z No. of bitstreams: 1 lilian_g_carvalho_ioc_bp_0040_2011.pdf: 1053182 bytes, checksum: 47bd05515041cbb3906d7cb295571be2 (MD5) / Made available in DSpace on 2012-09-25T11:49:38Z (GMT). No. of bitstreams: 1 lilian_g_carvalho_ioc_bp_0040_2011.pdf: 1053182 bytes, checksum: 47bd05515041cbb3906d7cb295571be2 (MD5) Previous issue date: 2011 / Instituto Oswaldo Cruz, Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Pesquisa do Estado do Rio de Janeiro (Faperj) / Fundação Oswaldo Cruz. Centro de Criação de Animais de Laboratório. Rio de Janeiro, RJ, Brasil / Evidências sorológicas e moleculares da infecção pelo vírus da hepatite E (HEV) em diferentes espécies animais de regiões endêmicas e não endêmicas, apontam para a possível transmissão zoonótica desse vírus. O conteúdo da presente dissertação é o resultado do estudo da infecção experimental em macacos cynomolgus (Macaca fascicularis) com o HEV, genótipo 3. A pesquisa baseou-se na avaliação da infecção com inóculos de diferentes origens geográficas, no estadiamento clínico da infecção do hospedeiro de origem bem como o emprego de um ensaio imunoenzimático para detecção de IgA anti-HEV como um teste confirmatório adicional. Tal ensaio foi utilizado uma vez que ainda não existe um “padrão ouro” de diagnóstico para identificação de casos agudos de infecções causadas pelo vírus da hepatite E. Um total de 12 animais foram divididos em grupos e inoculados com diferentes amostras de HEV pertencentes ao genótipo 3 provenientes de suínos do Brasil e da Holanda, de casos humanos da Argentina e um do Brasil, incluindo dois controles negativos. Os animais foram acompanhados por 67 dias, durante os quais foram coletados amostras semanais de sangue, saliva, fezes e tecido hepático por biópsia. A detecção do genoma viral foi realizada pela técnica de PCR em tempo real nas amostras de soro e fezes. As amostras de soro foram também avaliadas para quantificação bioquímica (método enzimático colorimétrico) de ALT, AST, GGT e bilirrubina total, e para sorologia de IgG, IgM e IgA anti-HEV. As amostras de saliva foram coletadas utilizando o coletor OraSure® e testadas para detecção de IgA anti-HEV. Seis animais dos dez inoculados tiveram o genoma detectado nas fezes e dentre estes, quatro também tiveram o genoma detectado no soro, o que ocorreu na ausência de evidências bioquímicas correspondentes as lesões hepáticas, que foram discretas a moderadas. A replicação viral precoce sem hepatite clínica seguida de soroconversão e início da hepatite histológica com infiltrados linfocíticos no fígado com baixa alteração de ALT indicam o caráter imunomediado da doença, não relacionado ao efeito direto da replicação viral. O estudo demonstra também que o vírus circulante em granjas suínas brasileiras foi capaz de desenvolver infecção em primatas não humanos reforçando a hipótese do potencial zoonótico do vírus da Hepatite E. / Evidences of infection of hepatitis E virus in different animal species of endemic and non endemic areas, point towards a possible zoonotic transmission of this virus. This study investigated experimental infection of HEV in cynomolgus monkeys (genotype 3) to assessing the course of infection with inocula from different geographical origins and clinical manifestations in the host of origin. Since there is still no gold standard for diagnosis to identify cases of acute hepatitis E, an enzyme immunoassay for detection of anti-HEV IgA was evaluated as an additional confirmatory test. A total of twelve animals were divided into groups and inoculated with different samples of HEV belonging to genotype 3 from pigs from Brazil and Holland, human cases from Argentina and Brazil, including two negative controls. The animals were monitored for 67 days, during which samples of blood, saliva, feces and liver biopsy were collected weekly. The detection of viral genome was performed by real-time PCR in serum and feces. Serum samples were evaluated to quantify biochemical (enzymatic colorimetric method) of ALT, AST, GGT and total bilirubin, and serology for anti-HEV IgG, IgM and IgA. Saliva samples were collected using the OraSure collector and tested for anti-HEV IgA. A total of six of the ten animals inoculated had the viral genome detected in the feces and of these, four also had the genome detected in the serum, which occurred in the absence of the corresponding biochemical evidence of liver injury, which were mild to moderate. The elimination of the virus in feces and viremia characterize infection and low ALT change confirms the status of an immune-mediated disease. The study also shows that the virus circulating in swine herds in Brazil was able to develop infection in nonhuman primates, suggesting that human acute cases of hepatitis E infection can occur in Brazil.

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