Missense Mutation in the Second RNA Binding Domain Reveals a Role for Prkra (PACT/RAX) during Skull Development

Random chemical mutagenesis of the mouse genome can causally connect genes to specific phenotypes. Using this approach, reduced pinna (rep) or microtia, a defect in ear development, was mapped to a small region of mouse chromosome 2. Sequencing of this region established co-segregation of the phenotype (rep) with a mutation in the Prkra gene, which encodes the protein PACT/RAX. Mice homozygous for the mutant Prkra allele had defects not only in ear development but also growth, craniofacial development and ovarian structure. The rep mutation was identified as a missense mutation (Serine 130 to Proline) that did not affect mRNA expression, however the steady state level of RAX protein was significantly lower in the brains of rep mice. The mutant protein, while normal in most biochemical functions, was unable to bind dsRNA. In addition, rep mice displayed altered morphology of the skull that was consistent with a targeted deletion of Prkra showing a contribution of the gene to craniofacial development. These observations identified a specific mutation that reduces steady-state levels of RAX protein and disrupts the dsRNA binding function of the protein, demonstrating the importance of the Prkra gene in various aspects of mouse development

Study protocol for a pragmatic cluster randomized controlled trial to improve dietary diversity and physical fitness among older people who live at home (the “ALAPAGE study”)

Background : Diet and physical activity are key components of healthy aging. Current interventions that promote healthy eating and physical activity among the elderly have limitations and evidence of French interventions’ effectiveness is lacking. We aim to assess (i) the effectiveness of a combined diet/physical activity intervention (the “ALAPAGE” program) on older peoples’ eating behaviors, physical activity and fitness levels, quality of life, and feelings of loneliness; (ii) the intervention’s process and (iii) its cost effectiveness. Methods : We performed a pragmatic cluster randomized controlled trial with two parallel arms (2:1 ratio) among people ≥60 years old who live at home in southeastern France. A cluster consists of 10 people participating in a “workshop” (i.e., a collective intervention conducted at a local organization). We aim to include 45 workshops randomized into two groups: the intervention group (including 30 workshops) in the ALAPAGE program; and the waiting-list control group (including 15 workshops). Participants (expected total sample size: 450) will be recruited through both local organizations’ usual practices and an innovative active recruitment strategy that targets hard-to-reach people. We developed the ALAPAGE program based on existing workshops, combining a participatory and a theory-based approach. It includes a 7-week period with weekly collective sessions supported by a dietician and/or an adapted physical activity professional, followed by a 12-week period of post-session activities without professional supervision. Primary outcomes are dietary diversity (calculated using two 24-hour diet recalls and one Food Frequency Questionnaire) and lower-limb muscle strength (assessed by the 30-second chair stand test from the Senior Fitness Test battery). Secondary outcomes include consumption frequencies of main food groups and water/hot drinks, other physical fitness measures, overall level of physical activity, quality of life, and feelings of loneliness. Outcomes are assessed before the intervention, at 6 weeks and 3 months later. The process evaluation assesses the fidelity, dose, and reach of the intervention as its causal mechanisms (quantitative and qualitative data). Discussion : This study aims to improve healthy aging while limiting social inequalities. We developed and evaluated the ALAPAGE program in partnership with major healthy aging organizations, providing a unique opportunity to expand its reach

Interroger l’efficacité des pratiques d’enseignement de la lecture-écriture au cours préparatoire

Qu’est-ce qui fait l’efficacité d’un enseignement du lire-écrire au début de l’école obligatoire (le cours préparatoire ou CP) ? Quelles sont les pratiques favorables aux élèves les plus fragiles ? Les dix contributions à ce numéro de Repères rendent compte de résultats issus de la recherche L’influence des pratiques d’enseignement de la lecture et de l’écriture sur la qualité des apprentissages au cours préparatoire, soutenue par l’IFÉ, la DGESCO du ministère de l’Éducation nationale et plusieurs laboratoires de recherche. Dans le cadre de cette étude, 131 classes françaises de CP ont été observées pendant une année scolaire et leurs 2 507 élèves évalués à trois reprises. Les données ont été analysées avec des méthodes statistiques et qualitatives. Les contributions réunies ici abordent la production des textes, la compréhension en lecture, l’acculturation des élèves à l’univers de l’écrit, les effets des pratiques d’encodage, l’étude de la langue. Elles cherchent notamment à éclairer ce qui caractérise les pratiques enseignantes lorsque les élèves d’origine sociale défavorisée progressent plus qu’ailleurs. Chaque article possède sa propre cohérence, mais la lecture croisée, à laquelle ce numéro invite, permet d’éviter de tirer trop vite d’un résultat une prescription pour l’action. Car si les résultats présentés, expliquant les performances des élèves, leurs progrès et les différences observées d’une classe à l’autre, peuvent inspirer des préconisations, celles-ci doivent embrasser la complexité des facteurs mis en évidence : il existe plusieurs configurations qui conduisent aux mêmes apprentissages. What brings about the effectiveness of the teaching of reading and writing at the beginning of compulsory primary schooling? And which practices favour weaker pupils? This edition of the academic review, “Repères”, puts together or collates ten research papers. These papers are resultant from a research conducted by IFÉ, DGESCO, the Ministry of Education and several other research laboratories on the theme: "The influence of teaching practices of reading and writing on the quality of learning in the primary school". As part of this study, 131 French primary school classes were observed during a particular school year out of which 2507 pupils were evaluated on three different occasions. The data were analyzed using statistical and qualitative methods. The contributions gathered here in this review deal with topics such as: writing tasks, reading comprehension, the pupils’ acculturation to the world of writing, the effects of encoding practices, and the study of language. These articles seek in particular to shed light on what is characteristic of teaching practices when pupils from deprived/disadvantaged social backgrounds begin to progress. Each article is also in itself coherent, but the cross-reading / comparative reading to which this review encourages makes it possible to avoid drawing too quickly conclusions to be enforced as prescriptive measures. This is because if the results presented, explaining the students' performances, their progress and the differences observed from one class to another, can inspire recommendations, then they must embrace the complexity of the factors highlighted which include the several configurations that lead to the same learning