RESUMEN
In chordates, the central nervous system arises from precursors that have distinct developmental and transcriptional trajectories. Anterior nervous systems are ontogenically associated with ectodermal lineages while posterior nervous systems are associated with mesoderm. Taking advantage of the well-documented cell lineage of ascidian embryos, we asked to what extent the transcriptional states of the different neural lineages become similar during the course of progressive lineage restriction. We performed single-cell RNA sequencing (scRNA-seq) analyses on hand-dissected neural precursor cells of the two distinct lineages, together with those of their sister cell lineages, with a high temporal resolution covering five successive cell cycles from the 16-cell to neural plate stages. A transcription factor binding site enrichment analysis of neural specific genes at the neural plate stage revealed limited evidence for shared transcriptional control between the two neural lineages, consistent with their different ontogenies. Nevertheless, PCA analysis and hierarchical clustering showed that, by neural plate stages, the two neural lineages cluster together. Consistent with this, we identified a set of genes enriched in both neural lineages at the neural plate stage, including miR-124, Celf3.a, Zic.r-b, and Ets1/2. Altogether, the current study has revealed genome-wide transcriptional dynamics of neural progenitor cells of two distinct developmental origins. Our scRNA-seq dataset is unique and provides a valuable resource for future analyses, enabling a precise temporal resolution of cell types not previously described from dissociated embryos.
Asunto(s)
Linaje de la Célula , Desarrollo Embrionario , Regulación del Desarrollo de la Expresión Génica , Animales , Linaje de la Célula/genética , Desarrollo Embrionario/genética , Placa Neural/embriología , Placa Neural/metabolismo , Placa Neural/citología , Ciona intestinalis/embriología , Ciona intestinalis/genética , Urocordados/embriología , Urocordados/genética , Análisis de la Célula Individual , Embrión no Mamífero/metabolismo , Embrión no Mamífero/citología , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Células-Madre Neurales/metabolismo , Células-Madre Neurales/citologíaRESUMEN
Background: Action research (AR) starts with an existing practical situation with which there is a concern or potential for improvement. It seeks transformative change through the simultaneous process of doing research and undertaking actions, both of which are linked together by a critical reflective process. It simultaneously allows one to systematically investigate a given social situation while promoting democratic change and collaborative participation. AR approaches have been used for many years in business management and education. More recently, AR has become an increasingly popular method of inquiry in healthcare, particularly in nursing, to investigate professional practice while simultaneously; introducing innovations; planning and undertaking action; and evaluating new ideas. The overall goal is to augment collaboration whilst improving the patient experience and outcomes. Methods: The Arksey and O'Malley methodology framework will be used to guide this scoping review process: stage 1 will identify the research questions; the eligibility criteria and search strategy will be defined in stage 2; studies will then be selected in stage 3; data will be extracted and charted from these included studies in stage 4; stage 5 involves aggregating and summarising these results along with criteria relevant for health professionals and policy-makers. An optional consultation (stage 6) exercise may potentially be included. Conclusion: This scoping review will comprehensively map the evidence on the use of AR methodology by healthcare professionals and in healthcare team settings. It is predicted that the findings will inform researchers in carrying out future AR and highlight gaps in the literature. An article reporting the results of the completed scoping review will be submitted for publication to a scientific journal and presented at relevant national and international conferences.