Beta-catenin-1 localization and transcriptomic profiling provide insights into the early development of planarians

ABSTRACT: Background: The development of planarians is unique among Spiralians. Instead of the stereotypical spiral cleavage, planarians exhibit a disperse cleavage. There is no apparent gastrulation, and the morphogenesis of the yolk-feeding embryo remains a mystery. In this study, we examine the subcellular localization of βcatenin-1 and the transcriptomic profile during the early embryonic development of Schmidtea polychroa to shed light on these early events. Results: We find that the first nuclearization of βcatenin-1 occurs in yolk cells surrounding the embryonic syncytium. By 24 hours post deposition, βcatenin-1 starts to be nuclearized in blastomeres, coinciding with the activation of signaling and cell motility genes. During morphogenesis of the yolk-feeding embryo, βcatenin-1 is first nuclearized at one pole (gut and pharynx progenitors) and in epidermal progenitors, and afterwards in the embryonic pharynx. At this stage, genes involved in a first morphogenetic event are turned on. Following the yolk ingestion by the embryo, a dramatic transcriptomic shift occurs that coincides with the activation of genes related to cell proliferation. Finally, between 5-7 days post deposition βcatenin-1 is massively nuclearized, and genes involved in the morphogenesis and patterning of the adult tissues get activated. Conclusions: Our findings provide new insights into the early developmental events of Schmidtea polychroa, including cleavage, the involvement of βcatenin-1 in the formation of the embryonic tissues and the morphogenesis of two distinct body plans. These findings are significant to understand the evolution of the peculiar mode of planarian development.

ORGANISM(S): Schmidtea polychroa

PROVIDER: GSE296729 | GEO | 2025/09/15

REPOSITORIES: GEO