GID complex regulates the differentiation of neural stem cells by destabilizing TET2 / 医学前沿

Brain development requires a delicate balance between self-renewal and differentiation in neural stem cells (NSC), which rely on the precise regulation of gene expression. Ten-eleven translocation 2 (TET2) modulates gene expression by the hydroxymethylation of 5-methylcytosine in DNA as an important epigenetic factor and participates in the neuronal differentiation. Yet, the regulation of TET2 in the process of neuronal differentiation remains unknown. Here, the protein level of TET2 was reduced by the ubiquitin-proteasome pathway during NSC differentiation, in contrast to mRNA level. We identified that TET2 physically interacts with the core subunits of the glucose-induced degradation-deficient (GID) ubiquitin ligase complex, an evolutionarily conserved ubiquitin ligase complex and is ubiquitinated by itself. The protein levels of GID complex subunits increased reciprocally with TET2 level upon NSC differentiation. The silencing of the core subunits of the GID complex, including WDR26 and ARMC8, attenuated the ubiquitination and degradation of TET2, increased the global 5-hydroxymethylcytosine levels, and promoted the differentiation of the NSC. TET2 level increased in the brain of the Wdr26+/- mice. Our results illustrated that the GID complex negatively regulates TET2 protein stability, further modulates NSC differentiation, and represents a novel regulatory mechanism involved in brain development.

A new gene inventory of the ubiquitin and ubiquitin-like conjugation pathways in Giardia intestinalis

BACKGROUND Ubiquitin (Ub) and Ub-like proteins (Ub-L) are critical regulators of complex cellular processes such as the cell cycle, DNA repair, transcription, chromatin remodeling, signal translation, and protein degradation. Giardia intestinalis possesses an experimentally proven Ub-conjugation system; however, a limited number of enzymes involved in this process were identified using basic local alignment search tool (BLAST). This is due to the limitations of BLAST's ability to identify homologous functional regions when similarity between the sequences dips to < 30%. In addition Ub-Ls and their conjugating enzymes have not been fully elucidated in Giardia. OBJETIVE To identify the enzymes involved in the Ub and Ub-Ls conjugation processes using intelligent systems based on the hidden Markov models (HMMs). METHODS We performed an HMM search of functional Pfam domains found in the key enzymes of these pathways in Giardia's proteome. Each open reading frame identified was analysed by sequence homology, domain architecture, and transcription levels. FINDINGS We identified 118 genes, 106 of which corresponded to the ubiquitination process (Ub, E1, E2, E3, and DUB enzymes). The E3 ligase group was the largest group with 82 members; 71 of which harbored a characteristic RING domain. Four Ub-Ls were identified and the conjugation enzymes for NEDD8 and URM1 were described for first time. The 3D model for Ub-Ls displayed the β-grasp fold typical. Furthermore, our sequence analysis for the corresponding activating enzymes detected the essential motifs required for conjugation. MAIN CONCLUSIONS Our findings highlight the complexity of Giardia's Ub-conjugation system, which is drastically different from that previously reported, and provides evidence for the presence of NEDDylation and URMylation enzymes in the genome and transcriptome of G. intestinalis.

Escala da Satisfação com a decisão em saúde: instrumento adaptado e validado para língua portuguesa / Decision making satisfaction in health scale: instrument adapted and validated to portuguese / Escala de la satisfacción con las decisiones en la salud: instrumento adaptado y validado para el idioma portugués

A tomada de decisão é uma área de investigação na saúde que tem vindo a ganhar importância quer pelos modelos de parceria de cuidados que dão protagonismo ao paciente e família, quer pela preocupação crescente com a qualidade e satisfação do cliente com os cuidados disponibilizados. Assim, propusemo-nos efetuar a adaptação transcultural e avaliar as propriedades psicométricas da versão portuguesa da "The Satisfaction with Decision Scale" de Holmes-Rovner (1996), que visa avaliar a satisfação com as decisões tomadas em saúde. A amostra foi constituída por 521 estudantes da Escola Superior de Enfermagem do Porto. Os resultados obtidos nos testes de fiabilidade revelam uma boa consistência interna para o total dos itens (Alpha Cronbach = 0,88). O estudo psicométrico permite-nos afirmar que a versão em Português da "The Satisfaction with Decision Scale", que denominamos "Escala da Satisfação com a Decisão em Saúde", é um instrumento fidedigno e válido.

Decision making is an area of health research that has gained importance both for the partnership models of care that give prominence to the patient and family, either by growing concern about quality and customer satisfaction with the care provided. So we decided to make the cultural adaptation and to evaluate the psychometric properties of the Portuguese version "The Satisfaction with Decision Scale" de Holmes-Rovner (1996), which aims to assess satisfaction with the decisions taken in health. The sample consisted of 521 nursing students the School of Nursing of Porto. The results of reliability tests show good internal consistency for the total items (Alpha Cronbach = 0.88). The psychometric study allows us to state that the Portuguese version of "The Satisfaction with Decision Scale", we call "Escala da Satisfação com a Decisão em Saúde", is an instrument comparable with the original in terms of validity and reliability.

La toma de decisiones es un área de investigación en salud que ha ganado importancia tanto por los modelos de atención dirigida al paciente y su familia, como por la creciente preocupación por la calidad y satisfacción del cliente con la atención recibida. Por esta razón decidimos hacer la adaptación transcultural y evaluar las propiedades psicométricas de la versión portuguesa "The Satisfaction with Decision Scale" de Holmes-Rovner (1996), que tiene como objetivo evaluar la satisfacción con las decisiones adoptadas en materia de salud. La muestra consta de 521 estudiantes de la Escuela de Enfermería del Porto. Los resultados de las pruebas de fiabilidad muestran una buena consistencia interna para la escala total (Alpha Cronbach = 0,88). El estudio psicométrico nos permite afirmar que la versión en portugués de "The Satisfaction with Decision Scale", que nosotros llamamos "Escala da Satisfação com a Decisão em Saúde", es válida.