Fig. 4: A progenitor cell pool that self-renews and differentiates.

A Molecular profiling of the progenitor cell pool recovered from the Elav>KikGR, FoxL2>KikGR and SoxC>KikGR drivers. (Top) S- phase and G2/M cycling genes module score across all clusters (same clustering and cluster colors as in Fig. 3E–G). (Bottom) Gene expression across all clusters. Dot size represents the proportion of cells in each cluster expressing the gene. Diverging temporal fates of progenitors. Ternary diagrams (B) and barplots with the recovered total cell numbers (C) showing the proportion of red, orange and green progenitor cells from the Elav>KikGR, SoxC>KikGR and FoxL2>KikGR drivers at 2, 4, and 7 days post-photoconversion. D Schematics of Piwi1⁺ progenitors giving rise to differentiated cells (top), with two possible expression dynamics: either expression of the driver occurs only in committed, differentiation-bound progenitors (middle) or already in self-renewing progenitors (bottom). For both scenarios, the corresponding progenitor cell color proportions at 7 days post-photoconversion are indicated on the right, with a majority of orange progenitor cells at 7 days indicative of driver expression in self-renewing progenitor cells, while a majority of green progenitor cells at 7 days is indicative of driver expression in differentiating and exit-committed progenitor cells. E Integrated model of progenitor cell temporal dynamics. Progenitors are a stable, self-renewing pool that expresses the FoxL2>KikGR driver; initiation of SoxC>KikGR or Elav>KikGR driver expression in progenitors is tied to differentiation initiation within days in vivo. Data is provided as Source Data File 4.