From coarse fate choice to precise pattern: post-mitotic progenitor targeting

Abstract

Planarians possess remarkable regenerative abilities, driven by pluripotent stem cells called neoblasts. While neoblasts are known to give rise to progenitor cells that form various tissues, whether and the extent to which these progenitors migrate across the animal remains unclear. Irradiation experiments eliminate all neoblasts outside shielded areas, allowing for the visualization of cell migration from the remaining neoblasts, but irradiated animals may not reflect homeostatic progenitor migration patterns. To address this, 5-ethynyl-2’-deoxyuridine (EdU) labeling and plug transplant techniques were used to trace progenitor movement in non-irradiated planarians. Using whole-mount fluorescence in situ hybridization (FISH) and the quantification of EdU-labeled cells, this study demonstrates that progenitor cells are capable of migrating long distances and exhibit a pronounced anterior bias in their movement and integration.