Fig. 3.

The ‘Janus’ progenitor state. scRNA-Seq has enabled the identification of embryonic progenitors that simultaneously express genes that were previously suspected of being lineage specific. (A) The PCA analysis of scRNA-Seq profiles of 198 developing murine lung cells has identified a cluster that expresses markers for both AT1 and AT2 cells, corroborating with single-cell qPCR data of E16.5 alveolar progenitors. (B) scRNA-Seq profiles of E11.5 metanephric mesenchyme has identified cells that co-express Foxd1 and Six2, which mark stromal-committing cells and nephron-committing cells, respectively. (C) A binary cell fate decision between the macrophage lineage and the neutrophil lineage was unveiled when bipotent progenitors were shown to co-express Irf8 and Gfi1, which regulate macrophage and neutrophil specification, respectively.