10 research outputs found
Resgatando a história demográfica e evolutiva dos primatas platyrrhini através de dados do sistema oxitocinérgico
A presente Tese apresenta um panorama sobre a história evolutiva e demografica de primatas Platyrrhini através da investigação do sistema oxitocinérgico. Primatas dessa parvorder formam um grupo monofilético que divergiram a aproximadamente 40Ma, ocupando uma diversidade de nichos ecologicos e comportamentais, apresentando uma alta taxa de comportamentos sociais complexos que não são comuns em primatas ou mamíferos em geral, como monogamia social ou cuidado paterno da prole. O presente estudo ampliou o conhecimento sobre genes do sistema oxitocinérgico (OXT, AVPR1b, AVPR2 e LNPEP) nas três famílias de primatas Platyrrhini: Cebidae, Pitheciidae e Atelide, aumentando a representativade em espécies sem informações genômicas em bancos de dados. A partir desta abordagem de análises coevolutivas e genômica comparativas podemos inferir sobre como a variabilidade do sistema nestas espécies de primatas influenciou nos diferentes padrões de comportamentos sociais encontrados. A presente Tese traz ainda manuscritos adicionais envolvendo temas relevantes como a evolução gene-cultura e outras abordagens evolutivas em co-autoria como a corrida armamentista entre patógenos e hospedeiros.This Thesis presents an overview of the evolutionary and demographic history of Platyrrhini primates through the investigation of the oxytocinergic system. Primates of this parvorder form a monophyletic group that diverged at approximately 40 Ma, occupying a diversity of ecological and behavioral niches, presenting a high rate of complex social behaviors that are not common in primates or mammals in general, such as social monogamy or paternal care of offspring. The present study expanded the knowledge about genes involved with the oxytocinergic system (OXT, AVPR1b, AVPR2 and LNPEP) in the three families of Platyrrhini primates: Cebidae, Pitheciidae and Atelide, increasing the representativeness in species without genomic information in databases. From comparative genomic and coevolutionary analyzes we can infer about how the variability of the oxytocinergic system of these primate species influenced their different patterns of social behavior. This Thesis also brings additional manuscripts involving relevant topics like gene-culture evolution and other evolutionary approaches in co-authorship such as pathogen and host arms race
ACE2 diversity in placental mammals reveals the evolutionary strategy of SARS-CoV-2
The recent emergence of SARS-CoV-2 is responsible for the current pandemic of COVID-19, which uses the human membrane protein ACE2 as a gateway to the host-cell infection. We perform comparative genomic analysis of 70 ACE2 placental mammal orthologues to identify variations and contribute to the understanding of evolutionary dynamics behind this successful adaptation to infect humans. Our results reveal that 4% of the ACE2 sites are under positive selection, all located in the catalytic domain, suggesting possibly taxon-specific adaptations related to the ACE2 function, such as cardiovascular physiology. Considering all variable sites, we selected 30 of them located at the critical ACE2 binding sites to the SARS-CoV-like viruses to analyze in more detail. Our results reveal a relatively high diversity of ACE2 between placental mammal species while showing no polymorphism within human populations, at least considering the 30 inter-species variable sites. A perfect scenario for natural selection favored this opportunistic new coronavirus in its trajectory of infecting humans. We suggest that SARS-CoV-2 became a specialist coronavirus for human hosts. Differences in the rate of infection and mortality could be related to the innate immune responses, other unknown genetic factors, as well as non-biological factors
ACE2 diversity in placental mammals reveals the evolutionary strategy of SARS-CoV-2
The recent emergence of SARS-CoV-2 is responsible for the current pandemic of COVID-19, which uses the human membrane protein ACE2 as a gateway to host-cell infection. We performed a comparative genomic analysis of 70 ACE2 placental mammal orthologues to identify variations and contribute to the understanding of evolutionary dynamics behind this successful adaptation to infect humans. Our results reveal that 4% of the ACE2 sites are under positive selection, all located in the catalytic domain, suggesting possibly taxon-specific adaptations related to the ACE2 function, such as cardiovascular physiology. Considering all variable sites, we selected 30 of them located at the critical ACE2 binding sites to the SARS-CoV-like viruses for analysis in more detail. Our results reveal a relatively high diversity of ACE2 between placental mammal species, while showing no polymorphism within human populations, at least considering the 30 inter-species variable sites. A perfect scenario for natural selection favored this opportunistic new coronavirus in its trajectory of infecting humans. We suggest that SARS-CoV-2 became a specialist coronavirus for human hosts. Differences in the rate of infection and mortality could be related to the innate immune responses, other unknown genetic factors, as well as non-biological factors
Evolutionary history of the SARS-CoV-2 Gamma variant of concern (P.1): a perfect storm
Our goal was to describe in more detail the evolutionary history of Gamma and two derived lineages (P.1.1 and P.1.2), which are part of the arms race that SARS-CoV-2 wages with its host. A total of 4,977 sequences of the Gamma strain of SARS-CoV-2 from Brazil were analyzed. We detected 194 sites under positive selection in 12 genes/ORFs: Spike, N, M, E, ORF1a, ORF1b, ORF3, ORF6, ORF7a, ORF7b, ORF8, and ORF10. Some diagnostic sites for Gamma lacked a signature of positive selection in our study, but these were not fixed, apparently escaping the action of purifying selection. Our network analyses revealed branches leading to expanding haplotypes with sites under selection only detected when P.1.1 and P.1.2 were considered. The P.1.2 exclusive haplotype H_5 originated from a non-synonymous mutational step (H3509Y) in H_1 of ORF1a. The selected allele, 3509Y, represents an adaptive novelty involving ORF1a of P.1. Finally, we discuss how phenomena such as epistasis and antagonistic pleiotropy could limit the emergence of new alleles (and combinations thereof) in SARS-COV-2 lineages, maintaining infectivity in humans, while providing rapid response capabilities to face the arms race triggered by host immuneresponses
Challenges in the information age: how technology resources may assist in science education and promote learning
Acompanhando o crescente uso de mídias e tecnologias pela sociedade, este trabalho tem como objetivo relatar uma vivência de inclusão digital no ensino de ciências em uma Escola Estadual de Ensino Fundamental de Porto Alegre, que proporcionou às crianças uma oportunidade de aprendizagem baseada nos princípios da educomunicação a partir do tema gerador “Água: um recurso vital”. Os alunos tiveram acesso a um website com vídeo, história em quadrinhos e uma tarefa pela qual foram incentivados a produzir seus próprios recursos midiáticos e a pesquisar em sua comunidade sobre o uso racional da água. As atividades promoveram a educação ambiental, a interação com a comunidade e a autonomia dos alunos. Os resultados obtidos sugerem que recursos midiáticos aliados à autoria dos alunos são ferramentas pedagógicas eficazes para uma aprendizagem significativa.Following the increasing use of media and technologies in society this paper aims to report an experience of digital inclusion in science education in a state elementary school, providing children a learning process based on the principles of educommunication, utilizing the discussion theme: “Water, a vital resource”. Students had access to a website with video, comics and a task where they were encouraged to produce their own media resources and research in their own communities the rational use of water. The activity promoted environmental education, interaction with the students’ community and the autonomy of students. Thus, demonstrating that the media resources are effective tools for meaningful learning
Boletín oficial de la provincia de Santander: Año XXX Número 105 - 1966 Septiembre 02
O sistema da Oxitocina-Vasopressina (OXT-AVP) é composto pelos neurohormônios e seus quatro receptores (OXTR, AVPR1a, AVPR1b e AVPR2). Além de suas relevantes funções fisiológicas durante o período reprodutivo e na homeostasia este sistema desempenha funções importantes na modulação de comportamentos sociais complexos. No presente diferentes espécies de mamíferos placentários mamíferos placentários foram analisadas para os seis genes deste sistema buscando investigar o papel destes genes durante o processo de domesticação animal. A comparação entre espécies domesticadas com seus ancestrais, quando disponível, ou com espécies selvagens filogeneticamente mais próximas revelou que este sistema está potencialmente envolvido na adaptação ao ambiente antrópico. Como consequência, assinaturas genéticas similares apareceram em espécies domesticadas pertencentes a grupos taxonômicos distintos que foram sujeitos a similiar pressão de seleção artificial. Especificamente AVPR2 mostra sinal de seleção positiva possivelmente pela alteração na disponibilidade de recursos hídricos e alimentares no ambiente antrópico. AVPR1b também apresentou sinal de seleção positiva demonstrando sua possível relevância na redução da agressividade e maior controle sobre o estresse, indispensável para o processo de domesticação. Além disso, fornecemos dados originais sobre a variabilidade de AVPR1b em primatas do Novo Mundo, com destaque para a deleção nas posições 245-248 da cadeia de aminoácidos do receptor. 6The Oxytocin-Vasopressin system is composed by two neurohormones (OXT and AVP) and their four receptors (OXTR, AVPR1a, AVPR1b and AVPR2). In addition to their important physiological functions in homeostasis and during reproductive period, this system plays important role modulating complex social behaviors. In the present study different species of placental mammals were analyzed for the six genes of the neurohormones and receptors mentioned above, to investigate their role in the animal domestication process. The comparison between domesticated mammals species with their wild ancestral when avaliable or with their phylogeneticaly closest wild relatives, reveled that this system is potentially involved in the adaptation to the anthropic environment. As consequence, similar genetic signatures appear in domesticated species belonging to distinct taxonomic groups, which were subjected to a similar artificial selection pressure. Specifically, AVPR2 shows signal of positive selection possibly due to differential food and water resources in anthropic environment. AVPR1b also presented signal of positive selection indicating the a possible relevance in the stress control and aggressiveness, traits indispensable during animal domestication process. Furthermore we presented original data regarding variability of AVPR1b in New World primates, highlighting a deletion at positions 245-248 on this receptor amino acid chain
Challenges in the information age: how technology resources may assist in science education and promote learning
Acompanhando o crescente uso de mídias e tecnologias pela sociedade, este trabalho tem como objetivo relatar uma vivência de inclusão digital no ensino de ciências em uma Escola Estadual de Ensino Fundamental de Porto Alegre, que proporcionou às crianças uma oportunidade de aprendizagem baseada nos princípios da educomunicação a partir do tema gerador “Água: um recurso vital”. Os alunos tiveram acesso a um website com vídeo, história em quadrinhos e uma tarefa pela qual foram incentivados a produzir seus próprios recursos midiáticos e a pesquisar em sua comunidade sobre o uso racional da água. As atividades promoveram a educação ambiental, a interação com a comunidade e a autonomia dos alunos. Os resultados obtidos sugerem que recursos midiáticos aliados à autoria dos alunos são ferramentas pedagógicas eficazes para uma aprendizagem significativa.Following the increasing use of media and technologies in society this paper aims to report an experience of digital inclusion in science education in a state elementary school, providing children a learning process based on the principles of educommunication, utilizing the discussion theme: “Water, a vital resource”. Students had access to a website with video, comics and a task where they were encouraged to produce their own media resources and research in their own communities the rational use of water. The activity promoted environmental education, interaction with the students’ community and the autonomy of students. Thus, demonstrating that the media resources are effective tools for meaningful learning
Oxytocin and arginine vasopressin systems in the domestication process
Domestication is of unquestionable importance to the technological revolution that has given rise to modern human societies. In this study, we analyzed the DNA and protein sequences of six genes of the oxytocin and arginine vasopressin systems (OXT-OXTR; AVP-AVPR1a, AVPR1b and AVPR2) in 40 placental mammals. These systems play an important role in the control of physiology and behavior. According to our analyses, neutrality does not explain the pattern of molecular evolution found in some of these genes. We observed specific sites under positive selection in AVPR1b ( = 1.429, p = 0.001) and AVPR2 ( = 1.49, p = 0.001), suggesting that they could be involved in behavior and physiological changes, including those related to the domestication process. Furthermore, AVPR1a, which plays a role in social behavior, is under relaxed selective constraint in domesticated species. These results provide new insights into the nature of the domestication process and its impact on the OXT-AVP system
Oxytocin and arginine vasopressin systems in the domestication process
Domestication is of unquestionable importance to the technological revolution that has given rise to modern human societies. In this study, we analyzed the DNA and protein sequences of six genes of the oxytocin and arginine vasopressin systems (OXT-OXTR; AVP-AVPR1a, AVPR1b and AVPR2) in 40 placental mammals. These systems play an important role in the control of physiology and behavior. According to our analyses, neutrality does not explain the pattern of molecular evolution found in some of these genes. We observed specific sites under positive selection in AVPR1b ( = 1.429, p = 0.001) and AVPR2 ( = 1.49, p = 0.001), suggesting that they could be involved in behavior and physiological changes, including those related to the domestication process. Furthermore, AVPR1a, which plays a role in social behavior, is under relaxed selective constraint in domesticated species. These results provide new insights into the nature of the domestication process and its impact on the OXT-AVP system