Distinct dynamics of muscle stem cells associated with the hyperplasia decline in trout - Archive ouverte HAL Accéder directement au contenu
Poster De Conférence Année : 2024

Distinct dynamics of muscle stem cells associated with the hyperplasia decline in trout

Résumé

Objective. Post-larval growth in salmonids is originally characterized by intense muscle hyperplasia. This process results from the specific proliferation and differentiation of muscle stem cells, also called satellite cells (SCs). While the evidence for the existence of a diversity of SC subtypes are clear in mammals, similar data on fish are still lacking. We aimed to elucidate the cellular and molecular dynamics of SCs during the decline of muscle hyperplasia in trout. Methods. First, we examined the kinetic of hyperplasia decline by evaluating the fiber size distribution in the white muscles of trout weighing from 10 g to 2 kg. We then, determined the in situ evolution of SC numbers in relation to this decline. Finally, we studied the diversity of SCs and cells in their niche, as well as their evolution during hyperplasia decline, using scRNAseq method on whole mononucleated cells extracted from trout muscle. Results. Our analysis revealed a continuous increase in mean diameter of fibers associated with a decrease of small fibers (<30 µm) strictly observed between 10 g and 1 kg. This suggests that hyperplasia in muscle decreases very early and ceases around 500 g - 1 kg. The in situ quantification of pax7+ cells indicated a weight-related decrease, reaching a minimum plateau at 500 g. Single-cell analyses allowed us to find that mononucleated cells of trout muscle were categorized in sixteen clusters. Eight clusters belonging to myogenic lineage were observed from quiescent SCs to myocytes. While a lower proportion of the myogenic precursors most engaged in the differentiation program is observed in the absence of hyperplastic growth, we interestingly showed that the proportion of the most primitive cells increases with weight gain. These shifts directly impact on SC heterogeneity and genetic networks, yielding specific transcriptomic signatures within myogenic cell subtypes. Additionally, we distinguished key cell types like mesenchymal cells (including fibro-adipogenic progenitors) which display shifts in proportions and molecular signatures with muscle growth, suggesting a potential involvement of the SC niche. Conclusion. Our results show the loss of generation of new committed myogenic precursors associated with the hyperplasia arrest, although the most primitive SCs are preserved, suggesting an orientation of the latter towards symmetrical division modalities. This study provides key insights into the fundamental biology of muscle growth in fish.
Fichier principal
Vignette du fichier
posterISSCR_SJagot_v2.pdf (1.15 Mo) Télécharger le fichier
posterISSCR_SJagot.pdf (1.06 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04496483 , version 1 (08-03-2024)

Identifiants

  • HAL Id : hal-04496483 , version 1

Citer

Sabrina Jagot, Nathalie Sabin, Candice Babarit, Jérôme Bugeon, Cécile Ralliere, et al.. Distinct dynamics of muscle stem cells associated with the hyperplasia decline in trout. French Society for Stem Cell Research, Jan 2024, Paris, France. ⟨hal-04496483⟩
3 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More