Sex chromosomes and autosomes often differ in their relative rates of evolution, with sex chromosomes generally accumulating changes more rapidly (faster-X evolution). Transposable elements (TEs) make up a significant portion of eukaryotic genomes and are some of the most rapidly evolving genetic elements. We compared relative rates of insertion on the X and autosomes for 78 families found in Drosophila melanogaster. The average X/A ratio for these TE families was 1.11, similar to the mean dS X/A ratio, indicating no male-bias in mutation rate or TE insertion. The major mode of the distribution was ~0.8, indicating stronger purifying selection on the X chromosome for most TEs. We found no effect on X/A from sex-specific TE expression, but TEs with male-specific piRNA had an average X/A ratio of 0.62. We also found that TEs with very high X/A ratios (top 5%) had X chromosome insertions in areas of relative low recombination.

Sex biased expression characterizes ~1,000 genes in mammalian liver, and impart sex differences in metabolism and disease susceptibility. The sex-dependent temporal patterns of pituitary growth hormone (GH) secretion, pulsatile in males and more continuous in females, are known to sex-differentially activate transcriptional regulators (TFs), leading to widespread sex-differences in the mouse liver transcriptome. This thesis elucidates sex-biased gene expression patterns in the following studies. Gene structures, expression patterns and species conservation are characterized for ~15,000 liver-expressed intergenic long noncoding RNAs (lncRNAs), many of which are novel. Analysis of intergenic lncRNA promoters revealed unexpected high conservation and significant enrichment of TF binding compared to protein-coding promoters. A subset of intergenic lncRNAs showed strong sex-specific and GH-dependent gene expression, and whose transcription was tightly correlated with the surrounding chromatin environment and TF binding patterns. The pervasive role of genetic factors to regulate sex-biased genes was revealed by analyzing livers with matched genotype and gene expression data from Diversity Outbred (DO) mice, an outbred population with high natural allelic variance derived from eight inbred strains. Significant associations between genetic variants and gene expression (eQTLs) were identified, including many eQTLs with a strong sex-biased association. Remarkably, a large fraction of these sex-biased eQTLs were linked to either gain or loss of sex-specific gene expression in the DO founder strain predicted to be regulated by the eQTL. Thus, genetic factors are a major contributor to the variability of sex-biased genes, which has important consequences related to the individual variability of liver phenotypes with known sex-differences. Natural genetic perturbations in DO mice were leveraged to identify candidate lncRNAs that may regulate hypophysectomy (hypox) responsiveness. Co-regulated protein-coding gene clusters were discovered based on gene expression correlations across DO mouse livers, many of which are enriched for distinct hypox response classes. LncRNAs whose expression showed unexpected significant negative correlation with protein-coding gene clusters enriched for genes of the opposite-sex bias and inverse hypox class were hypothesized to play negative regulatory role. In sum, these studies expand the characterization of the sex-biased hepatic transcriptome and reveal contributions of genetic factors to the regulation of sex bias in mammalian liver. / 2020-11-27T00:00:00Z

Orientador: José Antônio Dell’Aqua Junior / Resumo: O estudo proteômico é utilizado como ferramenta na reprodução animal como auxílio para compreesão da fisiologia das células. Neste sentido esta técnica é empregada em espermatozoides na tentativa de elucidar os processos biológicos e assim determinar os mecanismos moleculares envolvidos na separação do sexo. Assim, o objetivo deste estudo foi descrever as proteínas das células espermáticas de bovinos em diferentes aspectos. No estudo 1, investigou-se a influência do tampão de extração, associado ou não ao método mecânico (flash-frozen), e da concentração celular sobre a quantidade de proteínas extraídas de espermatozoides de bovinos. Foram utilizados como tampões TRIS contendo Nonidet P-40 (NP), RIPA modificado (RP) e uréia/tiuréia/CHAPS (UT), e as concentrações de 2, 4, 6, 8 e 10 x 106 espermatozoides/mL em grupos submetidos ou não ao flash-frozen. As concentrações de proteína total foram quantificadas e gel de eletroforese SDS-1D foi confeccionado. O tratamento UT recuperou maior concentração de proteínas, porém no RP as proteínas apresentaram melhor resolução no gel de eletroforese. A concentração protéica aumentou de acordo com a concentração de células no NP e UT. A influência do flash-frozen variou de acordo com o tratamento. No estudo 2, o objetivo foi traçar o perfil proteico de células espermáticas sexadas (X e Y) de bovinos. Foram utilizadas amostras comerciais de espermatozoides sexados X (n = 6) e Y (n = 6). As proteínas foram solubilizadas, submetidas a espectrom... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The proteomic study is used as a tool in animal reproduction as an aid to understanding of the cells physiology. In this regard, this technique is used in spermatozoa in an attempt to elucidate the biological processes and thus determine the molecular mechanisms involved in the sex separation. Therefore the aim of this study was to describe the bovine sperm cell proteins in different aspects. In study 1, the influence of the extraction buffer, associated or not to mechanical method (flash-frozen), and cellular concentration on the amount of proteins extracted from bovine spermatozoa were investigated. TRIS buffers containing Nonidet P-40 (NP), modified RIPA (RP) and urea/thiourea/CHAPS (UT) were used as well as concentrations of 2, 4, 6, 8 and 10 x 106 spermatozoa/mL in groups submitted or not to flash-frozen. Total protein concentrations were quantified and SDS-1D gel electrophoresis was prepared. The UT treatment recovered a higher concentration of proteins, but in RP the proteins showed better resolution in electrophoresis gel. The protein concentration increased according to the concentration of cells in the NP and UT. The influence of flash-frozen varied according to the treatment. In study 2, the objective was to map the protein profile of sexed sperm cells (X and Y) of cattle. Commercial samples of sexed spermatozoa X (n = 6) and Y (n = 6) were used. The proteins were solubilized, submitted to mass spectrometry SWATH analisys. 459 proteins common to the groups were ide... (Complete abstract click electronic access below) / Doutor

<p> Asthma is a multifactorial chronic disease that has shown a marked increase in prevalence over the past few decades, both in Canada and worldwide. Basic knowledge gaps remain about the pathways through which risk factors influence adult asthma. More adult women than men have asthma, and a growing body of research suggests that associations between certain risk factors and asthma may differ by sex. The aim of this thesis was to investigate the socioeconomic, environmental and personal correlates of asthma in men and women.</p> <p> Data for this thesis were obtained from a cross-sectional study conducted in 2003 in the rural Canadian town of Humboldt, Saskatchewan. The survey response rate was 71% of the resident target population, with 1177 females and 913 males aged 18 to 79 participating in the study. Researchers collected objective data on atopy (skin prick test), and body mass index. Exposures and history of physician-diagnosed asthma in the past year (current asthma) and during the participants lifetime (ever asthma) were self-reported. Multivariable logistic regression models adjusted for age, atopy, and parental asthma history were used to evaluate associations of correlates with asthma. The model building process was based on a conceptual framework of three categories: socioeconomic variables, home and work environment, and personal factors. </p> <p> The prevalence of asthma was higher in women than men (ever asthma: 10.2% of women versus 5.8% of men; current asthma: 6.2% of women versus 2.8% of men). The logistic regression models for ever asthma and current asthma showed several sex differences. The sequential addition of each category of socioeconomic, environmental, and personal variables contributed significantly to model fit in women, but not in men. Living in a mobile, attached or multiple-family home, household dampness, and overweight/obesity were strong risk factors for female asthma, while farm living, occupational grain dust exposure, and regular alcohol use emerged as protective factors. Male models revealed a strong significant association between household dampness and current asthma. A significant interaction between home type and age was found only in females. Women living in homes other than single-family detached dwellings were more likely to have asthma, an association that decreased in strength with increasing age. </p> <p> These results suggest that several risk factors for adult asthma may be sex-specific, therefore emphasizing the importance of considering sex as a potential effect modifier in future adult asthma epidemiology studies.</p>

<p> Asthma is a multifactorial chronic disease that has shown a marked increase in prevalence over the past few decades, both in Canada and worldwide. Basic knowledge gaps remain about the pathways through which risk factors influence adult asthma. More adult women than men have asthma, and a growing body of research suggests that associations between certain risk factors and asthma may differ by sex. The aim of this thesis was to investigate the socioeconomic, environmental and personal correlates of asthma in men and women.</p> <p> Data for this thesis were obtained from a cross-sectional study conducted in 2003 in the rural Canadian town of Humboldt, Saskatchewan. The survey response rate was 71% of the resident target population, with 1177 females and 913 males aged 18 to 79 participating in the study. Researchers collected objective data on atopy (skin prick test), and body mass index. Exposures and history of physician-diagnosed asthma in the past year (current asthma) and during the participants lifetime (ever asthma) were self-reported. Multivariable logistic regression models adjusted for age, atopy, and parental asthma history were used to evaluate associations of correlates with asthma. The model building process was based on a conceptual framework of three categories: socioeconomic variables, home and work environment, and personal factors. </p> <p> The prevalence of asthma was higher in women than men (ever asthma: 10.2% of women versus 5.8% of men; current asthma: 6.2% of women versus 2.8% of men). The logistic regression models for ever asthma and current asthma showed several sex differences. The sequential addition of each category of socioeconomic, environmental, and personal variables contributed significantly to model fit in women, but not in men. Living in a mobile, attached or multiple-family home, household dampness, and overweight/obesity were strong risk factors for female asthma, while farm living, occupational grain dust exposure, and regular alcohol use emerged as protective factors. Male models revealed a strong significant association between household dampness and current asthma. A significant interaction between home type and age was found only in females. Women living in homes other than single-family detached dwellings were more likely to have asthma, an association that decreased in strength with increasing age. </p> <p> These results suggest that several risk factors for adult asthma may be sex-specific, therefore emphasizing the importance of considering sex as a potential effect modifier in future adult asthma epidemiology studies.</p>

Co-occurring species of flowering plants may compete for pollination, which can cause character displacement by altering natural selection on floral traits. In a gynodioecious species, competition for pollination may also affect the evolution of sexual dimorphism of floral traits by influencing sex-specific selection. I demonstrated that Mimulus ringens did not affect seed set of gynodioecious Lobelia siphilitica, indicating that it is not a competitor for pollination. The presence of M. ringens did not alter selection upon most floral traits of L. siphilitica. I detected sex-specific selection upon five floral traits, supporting the hypothesis that sexual dimorphism evolves in response to sex-specific selection, rather than pleiotropic effects. My results also suggest that the presence of a co-flowering species may provide a context for sex-specific selection, and therefore, influence sexual dimorphism. Thus, my results suggest a link between the fields of study of competition for pollination and the evolution of sexual dimorphism. / NSERC, OGS, Ontario Innovation Trust, Canada Fund for Innovation

Submitted by CAROLINE SCOTT null (loraclol@yahoo.com.br) on 2017-08-30T16:56:06Z No. of bitstreams: 1 tese com ficha.pdf: 1676779 bytes, checksum: 1003b0a00f4220379e36033ae715d740 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-08-30T18:05:48Z (GMT) No. of bitstreams: 1 scott_c_dr_bot.pdf: 1676779 bytes, checksum: 1003b0a00f4220379e36033ae715d740 (MD5) / Made available in DSpace on 2017-08-30T18:05:48Z (GMT). No. of bitstreams: 1 scott_c_dr_bot.pdf: 1676779 bytes, checksum: 1003b0a00f4220379e36033ae715d740 (MD5) Previous issue date: 2017-08-25 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O estudo proteômico é utilizado como ferramenta na reprodução animal como auxílio para compreesão da fisiologia das células. Neste sentido esta técnica é empregada em espermatozoides na tentativa de elucidar os processos biológicos e assim determinar os mecanismos moleculares envolvidos na separação do sexo. Assim, o objetivo deste estudo foi descrever as proteínas das células espermáticas de bovinos em diferentes aspectos. No estudo 1, investigou-se a influência do tampão de extração, associado ou não ao método mecânico (flash-frozen), e da concentração celular sobre a quantidade de proteínas extraídas de espermatozoides de bovinos. Foram utilizados como tampões TRIS contendo Nonidet P-40 (NP), RIPA modificado (RP) e uréia/tiuréia/CHAPS (UT), e as concentrações de 2, 4, 6, 8 e 10 x 106 espermatozoides/mL em grupos submetidos ou não ao flash-frozen. As concentrações de proteína total foram quantificadas e gel de eletroforese SDS-1D foi confeccionado. O tratamento UT recuperou maior concentração de proteínas, porém no RP as proteínas apresentaram melhor resolução no gel de eletroforese. A concentração protéica aumentou de acordo com a concentração de células no NP e UT. A influência do flash-frozen variou de acordo com o tratamento. No estudo 2, o objetivo foi traçar o perfil proteico de células espermáticas sexadas (X e Y) de bovinos. Foram utilizadas amostras comerciais de espermatozoides sexados X (n = 6) e Y (n = 6). As proteínas foram solubilizadas, submetidas a espectromia de massas, análise SWATH. Foram identificadas 459 proteínas comuns aos grupos, 10 variaram a abundância relativa (p < 0,05) De acordo com os resultados obtidos nos 2 estudos conclui-se que a concentração de proteína recuperada em uma amostra varia de acordo com o tratamento e concentração celular. Não foram identificadas proteinas exclusivas presentes nos espermatozoides sexados para X ou Y, entretanto deve-se ressaltar que há uma contaminação de 10% com espermatozoides portadores dos cromossomos opostos, ainda assim, este estudo poderá ser utilizado como embasamento científico para novas pesquisas em busca de marcadores sexo-específicos. / The proteomic study is used as a tool in animal reproduction as an aid to understanding of the cells physiology. In this regard, this technique is used in spermatozoa in an attempt to elucidate the biological processes and thus determine the molecular mechanisms involved in the sex separation. Therefore the aim of this study was to describe the bovine sperm cell proteins in different aspects. In study 1, the influence of the extraction buffer, associated or not to mechanical method (flash-frozen), and cellular concentration on the amount of proteins extracted from bovine spermatozoa were investigated. TRIS buffers containing Nonidet P-40 (NP), modified RIPA (RP) and urea/thiourea/CHAPS (UT) were used as well as concentrations of 2, 4, 6, 8 and 10 x 106 spermatozoa/mL in groups submitted or not to flash-frozen. Total protein concentrations were quantified and SDS-1D gel electrophoresis was prepared. The UT treatment recovered a higher concentration of proteins, but in RP the proteins showed better resolution in electrophoresis gel. The protein concentration increased according to the concentration of cells in the NP and UT. The influence of flash-frozen varied according to the treatment. In study 2, the objective was to map the protein profile of sexed sperm cells (X and Y) of cattle. Commercial samples of sexed spermatozoa X (n = 6) and Y (n = 6) were used. The proteins were solubilized, submitted to mass spectrometry SWATH analisys. 459 proteins common to the groups were identified, 10 varied in relative abundance (p <0.05). According to the results obtained in the 2 studies it is concluded that the concentration of recovered protein in a sample varies according to the treatment and cellular concentration. No exclusive proteins were identified in spermatozoa sexed for X or Y, but it should be noted that there is a 10% contamination with spermatozoa bearing the opposite chromosomes, however, this study could be used as a scientific basis for further research in search of sex-specific markers. / FAPESP: 2013/23351-3

The mesocorticolimbic system is involved in fundamental processes that drive motivational behaviors essential for survival (feeding, reproduction and sexual behavior, etc.), as well as neurochemical activity involved in mood regulation. Stressful life events are an important cause of dysregulated psychological functioning, which in some leads to a pathophysiology of mood disorders. A source of such disorder could be, among other underlying factors, an impairment of synaptic plasticity induced by alterations in the levels of neurotrophins and/or aberrant glucocorticoid responses. The role of the brain derived neurotrophic factor (BDNF) and its high affinity receptor tyrosine-related kinase B (TrkB) in the mesocorticolimbic reward circuitry has been largely studied in adulthood, yet a possible role of this system in mediating memory and emotional responses induced by stress during the juvenile, adolescence period has not been elucidated. The proposed set of thesis studies are designed to investigate the roles of BDNF and TrkB signaling, via the selective and non-competitive TrkB antagonist, ANA-12 (N-[2-[[(Hexahydro-2-oxo-1H-azepin-3-yl)amino]carbonyl]phenyl] benzo[b]thiophene-2-carboxamide), in the expression of stress-induced changes in the brain stress circuitry (including the medial prefrontal cortex (mPFC), hypothalamic-pituitary-adrenal (HPA) axis, and hippocampus) and reward signaling systems of the brain (including the nucleus accumbens (NAc) and ventral tegmental area (VTA)). In addition, experiments aim to determine behavioral changes following stress exposure in male and female Wistar rats. Finally, the possible interplay between BDNF, dopamine, glutamate and orexins in response to repeated stress is examined. Articles 1 and 2, aimed to assess the biochemical and behavioral effects of direct ANA-12 infusion (0.25 µg/ 0.5µl) into the nucleus accumbens shell during exposure to a 10-day heterotypic stress paradigm in male rats. Specifically, Article 1 demonstrated a key role for BDNF/TrkB signaling to regulate stress-induced effects. Notably, the impact of ANA-12 to attenuate anxiety-like behavior in repeatedly stressed rats while increasing anxiety behavior in non-stress rats suggest an interesting behavioral and neurochemical state-dependent process induced by TrkB receptor signaling. Article 2 supports the key role for BDNF secretion in basal and stress-induced behaviors in rats suggesting an influence of TrkB in sociability, motivation and passive avoidance. Furthermore, this role of TrkB extended to increased expression of orexin A in the Perifornical area (PfA) and a decrease in the ventral CA1 of the hippocampus, and in stress-induced elevations in orexinergic projections to the VTA, of which reductions were observed in non-stress groups treated with ANA-12. Article 3 demonstrated gender-specific behavioral and biochemical responses in different developmental periods and the impact of TrkB activation, dependent on stress exposure, to affect the regulation of TrkB receptor isoforms (full length and truncated TrkB, TrkB.FL and TrkB.T1, respectively) in adulthood. Results revealed increased CORT responses in adolescent females relative to males and attenuated CORT secretions in both genders by TrkB inhibition. Elevated activity levels in young adult females and increased passive coping behavior in the forced swim in stress-naïve females were also noted, in addition to novel observations on brain region and sex differences in TrkB receptor isoforms. Taken together, thesis findings derived from applications of ANA-12, shall foster knowledge on the contribution of BDNF in regulation of mood upon stress exposure at times when the brain is undergoing important maturation and remodelling, as well as on the relationship of stress exposure during adolescence and lasting brain and behavioral disorders in adulthood.

The ability of organisms to sense – and properly respond to – their environment is crucial to their survival. Higher organisms communicate with conspecifics to ensure the survival of the species. Nematodes, such as the roundworm Caenorhabditis elegans, are ubiquitous across all biomes, and rely on chemical communication to convey information with one another. The small molecules they utilize in this communication are called ascarosides. These modular pheromones are employed by all taxa, ranging from Caenorhabditis to Ascaris. The ascaroside, ascr#8, is release by hermaphroditic C. elegans to attract potential mates. Previous work has shown that a class of male specific neurons are required for sensation of this pheromone. Here, we show that these neurons initiate a neural circuit modulated by the FMRFamide-like neuropeptide, flp-3. This neuropeptide is sensed by a set of G protein-coupled receptors (GPCRs), NPR-10 and FRPR-16. Together, these components determine the behavioral valence of males to ascr#8. Within the male-specific sensory neurons, the CEM, we show that another group of GPCRs sense the ascr#8. Two of these receptors, DMSR-12 and SRW-97, are expressed in the cilia, suggesting their involvement in direct sensation of the cue. As a targeted approach to identifying and confirming receptors for ascr#8, we have developed a bioactive photoaffinity probe. We have also confirmed that the ability of ascr#8 to attract males is conserved across the genus. Together, these studies coalesce to deepen our understanding of sex-specific chemosensation and neuronal processing. These results can be used to better understand the defects that are seen in neurodegenerative diseases – many of which exhibit sex-specific defects in neuronal processing.

DNA methylation patterns are sex and tissue specific in many species, yet many studies useblood samples, due to its accessibility, to establish links between the DNA methylation anddifferent phenotypes. This raises the question of whether DNA methylation in blood samplesreflect the DNA methylation pattern in other tissues that are more relevant to the phenotypebeing studied. In this research, samples were collected from the brain, blood, liver and gonadof 16 house sparrow (Passer domesticus), half of them were female, while the others weremale. Reduced representation bisulfite sequencing (RRBS) was performed to get themethylation profile in each sample. The result showed a tissue specific methylation profile inthe four investigated tissues, a strong and positive correlation between 0.74 – 0.85 was foundbetween tissues, in which a weaker correlation was found between blood and other tissue. Indifferential methylation analysis, most of the differently methylated sites between sexes werefound in gonads, while the fewest was found in blood, and Z chromosome wasoverrepresented place in all four tissues where the majority of the differently methylated sitesbetween sexes were found. Comparison with the house sparrow genome annotation foundabout half of the differentially methylated sites between sexes were within genes and about 20 % of them were in the exon or coding region of a gene. The result suggested that bloodcould be useful in reflecting the general DNA methylation level in other tissues, but it was nota reliable bioindicator for further detailed study in DNA methylation pattern or in geneontology enrichment pathway analysis.