Intestinal Enteroendocrine Lineage Cells Possess Homeostatic and Injury-Inducible Stem Cell Activity

Several cell populations have been reported to possess intestinal stem cell (ISC) activity during homeostasis and injury-induced regeneration. Here, we explored inter-relationships between putative mouse ISC populations by comparative RNA-sequencing (RNA-seq). The transcriptomes of multiple cycling ISC populations closely resembled Lgr5+ ISCs, the most well-defined ISC pool, but Bmi1-GFP+ cells were distinct and enriched for enteroendocrine (EE) markers, including Prox1. Prox1-GFP+ cells exhibited sustained clonogenic growth in vitro, and lineage-tracing of Prox1+ cells revealed long-lived clones during homeostasis and after radiation-induced injury in vivo. Single-cell mRNA-seq revealed two subsets of Prox1-GFP+ cells, one of which resembled mature EE cells while the other displayed low-level EE gene expression but co-expressed tuft cell markers, Lgr5 and Ascl2, reminiscent of label-retaining secretory progenitors. Our data suggest that the EE lineage, including mature EE cells, comprises a reservoir of homeostatic and injury-inducible ISCs, extending our understanding of cellular plasticity and stemness. [Display omitted] •Bmi1-GFP+ cells express mature enteroendocrine (EE) genes, including Prox1•Prox1-GFP+ and Bmi1-GFP+ cells exhibit intestinal stem cell-like clonogenic growth.•Prox1+ cells co-express EE and tuft cell genes in vivo•Lineage tracing shows that Prox1+ cells contribute to crypt homeostasis and regeneration Multiple cell populations, represented by distinct markers including Lgr5 and Bmi1, are capable of reconstituting the intestinal epithelium. Using comparative RNA-sequencing and single-cell transcriptomics, Yan et al. define Bmi1-GFP+ and Prox1+ cells as enteroendocrine lineage cells that possess intestinal stem cell activity during homeostasis and injury-induced regeneration.