Adult tissues are maintained throughout life through the renewal of differentiated cells by adult stem cells, but what controls the competing processes of stem cell self-renewal and differentiation? On , Allison Bardin, François Schweisguth and colleagues present a new model for the transcriptional control of stem cell maintenance in the Drosophila intestine. When Drosophila intestinal stem cells (ISCs) divide, one daughter cell retains the ISC fate while the other becomes an enteroblast, which differentiates into two mature cell types. Using lineage mapping and genetic manipulation, the researchers show that ISC maintenance requires the transcriptional repression of key Notch target genes – in particular, the Enhancer of split complex (E(spl)-C) genes – by a Hairless–Suppressor of Hairless complex. Furthermore, Daughterless, a bHLH transcriptional activator, is also needed for ISC maintenance. From their results, the researchers propose that Daughterless and E(spl)-C factors act antagonistically to maintain the balance between ISC self-renewal and differentiation.
