The human C1 heterogeneous nuclear ribonucleoprotein particle protein (hnRNP protein) undergoes a cycle of phosphorylation-dephosphorylation in HeLa cell nuclear extracts that modulates the binding of this protein to pre-mRNA. We now report that hyperphosphorylation of the C1 hnRNP protein is mediated by a kinase activity in nuclear extracts that is RNA-dependent. Although the basal phosphorylation of the C1 hnRNP protein in nuclear extracts ref lects a casein kinase II-type activity, its RNA-dependent hyperphosphorylation appears to be mediated by a different kinase. This is indicated by the unresponsiveness of the RNA-stimulated hyperphosphorylation to casein kinase II inhibitors, and the distinct glycerol gradient sedimentation profiles of the basal versus RNA-stimulated C1 hnRNP protein phosphorylation activities from nuclear extracts. RNAdependent phosphorylation was observed both for a histidinetagged recombinant human C1 hnRNP protein added to nuclear extracts and also for the endogenous C1 hnRNP protein. Additional results rule out protein kinase A, protein kinase C, calmodulin-dependent protein kinase II, and double-stranded RNA-activated protein kinase as the enzymes responsible for the RNA-dependent hyperphosphorylation of the C1 hnRNP protein. These results reveal the existence in nuclear extracts of an RNA-dependent protein kinase activity that hyperphosphorylates a known pre-mRNA binding protein, and define an additional element to be integrated into the current picture of how nuclear proteins are regulated by phosphorylation.Approximately 20 characterized heterogeneous nuclear ribonucleoprotein particle proteins (hnRNP proteins) bind to pre-mRNA soon after its transcription and may play a role in the early posttranscriptional steps of pre-mRNA processing (1-3). We have recently reported that the C1 hnRNP protein, one of the most abundant hnRNP proteins, undergoes a cycle of phosphorylation-dephosphorylation in HeLa cell nuclear extracts which modulates its binding to pre-mRNA, and that the dephosphorylation step of this cycle is facilitated by the 3Ј end of U6 small nuclear RNA (4, 5). In the course of this work we found that the phosphorylation level of the C1 hnRNP protein was greatly reduced in nuclear extracts in which endogenous nucleic acids had been previously eliminated by nuclease digestion (5). Pursuit of this finding has revealed the presence of a protein kinase activity in nuclear extracts that hyperphosphorylates the C1 hnRNP protein in an RNAdependent manner. MATERIALS AND METHODSNuclear extracts were prepared from exponentially growing HeLa cells as described (6). Nuclear extracts from a human T cell leukemia line (Jurkat) were obtained from Promega. Prior to use, nuclear extracts were incubated with micrococcal nuclease (Worthington) at 200 units͞ml in the presence of 10 mM CaCl 2 for 30 min at 30ЊC. The extracts were then brought to 4ЊC, EGTA was added to 75 mM, and the extracts were made 4.8 mM in MgCl 2 , 600 M in ATP, and 30 mM in creatine phosphate. RNasin (Promega) wa...
Une des grandes orientations de la formation des enseignants au Québec est la professionnalisation (Gouvernement du Québec, 2001). Afin de favoriser cette professionnalisation, il est essentiel de construire la structure de formation à partir de l’analyse réflexive en milieu réel (Perrenoud, 2001), et ce, en mobilisant un ensemble de ressources dont les savoirs théoriques et les savoirs pratiques (Perrenoud, 1998). Ainsi, les étudiants entrent dans un processus de développement professionnel, à savoir un processus de changement et de transformation (Uwamariya & Mukamurera, 2005) soutenu par la pratique réflexive (Buysse & Vanhulle, 2009). Depuis 2014, une équipe de chercheures de l’Université du Québec à Chicoutimi expérimente l’implantation du ePortfolio dans le cadre des stages. Cet article présente l’analyse des points de vue de superviseurs universitaires (SU) et d’enseignants associés (EA) sur : 1) les liens réalisés entre les cours et les stages par le biais du ePortfolio; 2) l’accompagnement offert par le SU et l’EA pour faciliter la réflexion autour des liens et; 3) les retombées du ePortfolio sur l’évaluation du stagiaire. Cet article aborde les résultats d’une enquête par questionnaire réalisée auprès d’enseignants associés (N = 19) ainsi que ceux issus de deux groupes de discussion réunissant des superviseurs universitaires (N = 8). Trois constats émergent de cette recherche, à savoir que, dans sa forme actuelle, le ePortfolio facilite les liens entre les différents types de savoir, mais les liens sont peu explicites pour les accompagnateurs (SU et EA); la logique d’accompagnement avec le ePortfolio est avant tout normative et spéculative et, finalement, que le ePortfolio a une fonction de régulation pour l’EA, mais pas pour les SU. En conclusion, des recommandations pour l’intégration de ePortfolio sont formulées à cet effet. One of the main focuses of the teacher training in Quebec is professionalization (Government of Quebec, 2001). To promote this professionalization, it is essential to build the training structure from field reflective analysis (Perrenoud, 2001), by mobilizing a series of resources including theoretical and practical knowledge (Perrenoud, 1998). As such, students embark on a professional development process, or a process of change and transformation (Uwamariya & Mukamurera, 2005) supported by reflective practice (Buysse & Vanhulle, 2009). Since 2014, a research team at the Université du Québec à Chicoutimi has been experimenting with the implementation of the ePortfolio as part of internships. This article presents the analysis of the points of view of academic supervisors (ASs) and associate professors (APs) on: 1) the links created between the courses and the internships with the ePortfolio; 2) support provided by the ASs and APs to foster reflection on these links and; 3) the implications of the ePortfolio on the evaluation of the intern. This article examines the results of a survey conducted among associate professors (N = 19) as well as those stemming from two discussion groups composed of academic supervisors (N = 8). Three factors emerge from this research, namely that in its current form, the ePortfolio fosters links between the various types of knowledge, but these links are rather unclear for those accompanying the students (ASs and APs); the assistance logic with the ePortfolio is normative and speculative, first and foremost, and lastly, that the ePortfolio has a regulating function for the AP, but not for the AS. Recommendations for the integration of the ePortfolio are made in this regard.
Au Québec, les fonctions de l’enseignant associé et du superviseur universitaire sont balisées par un référentiel de compétences (Portelance, Gervais, Lessard et Beaulieu, 2008), lequel a fait l’objet d’études (L’Hostie, Cody, Cividini, Allaire et Gauthier, 2008-2011 ; Cody, Cividini et L’Hostie, 2011-2013) démontrant que ces acteurs clés souhaitent collaborer plus efficacement et aider le stagiaire à établir des liens entre les savoirs formels et expérientiels en formation initiale. Afin de répondre à ce besoin, une équipe composée de chercheurs universitaires, d’enseignants associés et de superviseurs universitaires a repensé l’usage du portfolio numérique pour en faire un outil d’accompagnement et de collaboration. Des données issues d’un questionnaire (n = 19) et de deux focus groups (n = 8) ont été analysées du point de vue de la collaboration entre les enseignants associés et les superviseurs universitaires. L’article mettra en lumière les résultats obtenus au terme de deux années d’expérimentation, notamment l’impact du dispositif sur la collaboration entre ces deux catégories d’intervenants.
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