Formação inicial de professores e educação de jovens e adultos: possibilidades da extensão universitária

The present work aimed at investigating the possibilities and limits of academic extension programs as an environment for initial teacher learning and training. It also focused on investigating the main difficulties identified by Pedagogy and Social Science students about this initial training regarding its use in actual teaching activities. It focused on undergraduate students’ perceptions concerning their involvement in an academic extension project which enabled them to interact with students as teachers in a Youth and Adult Education program, during a whole academic year. Semi-structured interviews were done with nine participants. The content of these interviews was analyzed and divided into four thematic categories. The results show that, for these students, what makes this kind of project unique is the possibility of acting in real situations, under supervision, which provided a moment for reflection. Focusing on supervision, the students point out that this resource is not usually there in traditional internship situations – and that they consider it an important and necessary aspect. It was also indicated the relevance of practice, self-awareness and teaching activity experiences. In conclusion, it was perceived that academic extension programs must be more intensively appreciated, given the coordinating role it can play between investigative and didactic activities, both key to initial training.O trabalho que aqui se apresenta teve como objetivo investigar possibilidades e limites da extensão universitária como ambiente de aprendizagem e formação inicial de professores, propondo-se também a analisar as principais dificuldades identificadas por alunos dos cursos de Pedagogia e Ciências Sociais (licenciatura) acerca dessa formação inicial para o exercício da atividade docente. Focaliza as percepções de graduandos em relação à participação em um projeto de extensão que lhes possibilitou atuar como professores de alunos em sala de aula da Educação de Jovens e Adultos (EJA), durante um ano letivo. Foram realizadas entrevistas semi-estruturadas com nove participantes. O conteúdo das falas foi analisado e organizado em quatro categorias temáticas. Os resultados mostram que, para esses graduandos, o diferencial da extensão universitária é que a mesma oferece a oportunidade de atuação numa situação real, porém sob supervisão, evidenciando um espaço de reflexão originada na prática. Dando ênfase à supervisão, os alunos valorizam esse recurso como relevante e mencionam ser justamente ele que não está presente de forma habitual nas situações tradicionais de estágio. Destacam também a relevância da prática, da autopercepção e da vivência do fazer docente. Concluindo, percebe-se que os dados são indicativos de que, com pouca visibilidade no contexto acadêmico, atividades extensionistas necessitariam ser mais e intensamente valorizadas, dado o papel articulador que podem exercer entre as atividades investigativas e didáticas, essenciais para a formação inicial

Publicações para o professor: um estudo de caso.

O trabalho consiste numa análise da revista Escola, publicação voltada para os professores. A história da revista, de 72 a 74, e os dados levantados através da análise de suas matérias revelam uma visão instrumental do papel do professor, que apesar do enfoque interdisciplinar, não estabelece uma ligação entre sua tarefa e os condicionantes sociais mais amplos

Histone H1 protects telomeric repeats from H3K27me3 invasion in Arabidopsis

Linker histones play a pivotal role in shaping chromatin architecture, notably through their globular H1 (GH1) domain that contacts the nucleosome and linker DNA. Yet, the interplay of H1 with chromatin factors along the epigenome landscape is poorly understood. Here, we report that Arabidopsis H1 favors chromatin compaction and H3K27me3 marking on a majority of Polycomb-targeted protein-coding genes while preventing H3K27me3 accumulation on telomeres and pericentromeric interstitial telomeric repeats (ITRs). These contrasting effects of H1 on H3K27me3 enrichment are associated with long-distance effects on the 3D organization of telomeres and ITRs. Mechanistically, H1 prevents ITRs from being invaded by Telomere Repeat Binding 1 (TRB1), a GH1-containing telomere component with an extra-telomeric function in targeting Polycomb to genes bearing telomeric motifs. We propose that reciprocal DNA binding of H1 and TRB1 to clustered telobox motifs prevents H3K27me3 accumulation on large chromosomal blocks, conferring a sequence-specific role to H1 in epigenome homeostasis

Beneficial Effects of Dietary Polyphenols on Gut Microbiota and Strategies to Improve Delivery Efficiency

The human intestine contains an intricate ecological community of dwelling bacteria, referred to as gut microbiota (GM), which plays a pivotal role in host homeostasis. Multiple factors could interfere with this delicate balance, including genetics, age, antibiotics, as well as environmental factors, particularly diet, thus causing a disruption of microbiota equilibrium (dysbiosis). Growing evidence support the involvement of GM dysbiosis in gastrointestinal (GI) and extra-intestinal cardiometabolic diseases, namely obesity, and diabetes. This review firstly overviews the role of GM in health and disease, then critically reviews the evidence regarding the influence of dietary polyphenols in GM based on preclinical and clinical data, ending with strategies under development to improve the efficiency of delivery. Although the precise mechanisms deserve further clarification, preclinical and clinical data suggest that dietary polyphenols present prebiotic properties and exert antimicrobial activities against pathogenic GM, having benefits in distinct disorders. Specifically, dietary polyphenols have been shown the ability to modulate GM composition and function, interfering with bacterial quorum sensing, membrane permeability, as well as sensitizing bacteria to xenobiotics. In addition, can impact gut metabolism and immunity and exert anti-inflammatory properties. In order to overcome the low bioavailability, several different approaches have been developed, aiming to improve the solubility and transport of dietary polyphenols throughout the GI tract and deliver in the targeted intestinal regions. Although more research is still needed, particularly translational and clinical studies, the biotechnological progress achieved during the last years opens up good perspectives to, in a near future, be able to improve the use of dietary polyphenols modulating GM in a broad range of disorders characterized by a dysbiotic phenotype

Histone H1 protects telomeric repeats from H3K27me3 invasion in Arabidopsis

Linker histones play a pivotal role in shaping chromatin architecture, notably through their globular H1 (GH1) domain that contacts the nucleosome and linker DNA. Yet, the interplay of H1 with chromatin factors along the epigenome landscape is poorly understood. Here, we report that Arabidopsis H1 favors chromatin compaction and H3K27me3 marking on a majority of Polycomb-targeted protein-coding genes while preventing H3K27me3 accumulation on telomeres and pericentromeric interstitial telomeric repeats (ITRs). These contrasting effects of H1 on H3K27me3 enrichment are associated with long-distance effects on the 3D organization of telomeres and ITRs. Mechanistically, H1 prevents ITRs from being invaded by Telomere Repeat Binding 1 (TRB1), a GH1-containing telomere component with an extra-telomeric function in targeting Polycomb to genes bearing telomeric motifs. We propose that reciprocal DNA binding of H1 and TRB1 to clustered telobox motifs prevents H3K27me3 accumulation on large chromosomal blocks, conferring a sequence-specific role to H1 in epigenome homeostasis

Histone H1 protects telomeric repeats from H3K27me3 invasion in Arabidopsis

Summary: While the pivotal role of linker histone H1 in shaping nucleosome organization is well established, its functional interplays with chromatin factors along the epigenome are just starting to emerge. Here we show that, in Arabidopsis, as in mammals, H1 occupies Polycomb Repressive Complex 2 (PRC2) target genes where it favors chromatin condensation and H3K27me3 deposition. We further show that, contrasting with its conserved function in PRC2 activation at genes, H1 selectively prevents H3K27me3 accumulation at telomeres and large pericentromeric interstitial telomeric repeat (ITR) domains by restricting DNA accessibility to Telomere Repeat Binding (TRB) proteins, a group of H1-related Myb factors mediating PRC2 cis recruitment. This study provides a mechanistic framework by which H1 avoids the formation of gigantic H3K27me3-rich domains at telomeric sequences and contributes to safeguard nucleus architecture