Drosophila intestinal stem and progenitor cells are major sources and regulators of homeostatic niche signals

Abstract

SignificanceMost epithelia are turned over throughout adult life as cells are lost from the surface and replaced by the proliferation of stem cells. Precise regulation of stem cells by signals from the local microenvironment or niche is important to maintain epithelial homeostasis. Here, using intestinal stem cells of the Drosophila midgut as a model system, we use transcriptome profiling to identify genes expressed specifically in stem and progenitor cells and not their differentiated daughters. We find that stem and progenitor cells express ligands of major developmental signaling pathways to both contribute to the niche and regulate the production of niche signals from other cell types.

Non-apoptotic caspase-dependent regulation of enteroblast quiescence in Drosophila

“…Since our data was collected in experimental conditions without cellular turnover, Dronc seemed to restrain EBs in a quiescent state. To further characterise the differentiation features of Dronc mutant progenitor cells, we next analysed the expression profile of metabolic enzymes highly enriched in ECs [39]. Interestingly, we found that several of these genes were transcriptionally downregulated in our mutant conditions, while others were upregulated (Appendix Fig 3F-H).…”

Asymmetric histone inheritance regulates stem cell fate in Drosophila midgut

“…The results reported in this paper provide a solid basis to addressing these questions. Despite significant differences in the niche structure, signaling cascades for regulating stem cell activity, and cellular differentiation pathways between the ISC and GSC lineages [(Amoyel et al, 2014;Doupe et al, 2018;Jiang et al, 2011;Jiang et al, 2009;Kiger et al, 2001;Leatherman and Dinardo, 2008;Li et al, 2014;Lin et al, 2008;Ohlstein and Spradling, 2007;Stine et al, 2014;Tulina and Matunis, 2001) and reviewed in (de Cuevas and Matunis, 2011;Kahney et al, 2019;Losick et al, 2011;Morrison and Spradling, 2008)], many features of asymmetric histone inheritance are common between these two stem cell systems. First, the cellular specificity in the GSC lineage has been shown by asymmetric histone inheritance in asymmetrically dividing GSCs but not in symmetrically dividing spermatogonial cells.…”

The Cellular Diversity and Transcription Factor Code of Drosophila Enteroendocrine Cells

“…Interestingly, EE-C10, a unique cluster, was distinguished by a relatively low level of pros expression and high levels of Dl and Notch expression (Figures 1D and 1E). These cells also retained the expression of ISCenriched genes, including Sox21a and Sox100b, as well as several ISC-specific E(spl)-C genes such as m3 and ma (Chen et al, 2016b;Doupé et al, 2018;Guo et al, 2019;Meng and Biteau, 2015;Zhai et al, 2015) ( Figure S2A, highlighted in blue), indicating that these cells are EE progenitor cells (EEPs), and each of them usually gives rise to a pair of EEs by dividing once before terminal differentiation (Chen et al, 2018).…”