The study by Tudorita Tumbar and colleagues investigates the epithelial stem cell (SC) niche in the skin, focusing on the bulge region of hair follicles. They developed a method to fluorescently label slow-cycling cells, specifically label-retaining cells (LRCs), which are markers of the skin SC niche. These LRCs rarely divide within their niche but exhibit rapid proliferation and differentiation when stimulated to exit. The researchers characterized the transcriptional profile of these LRCs, finding that many of the >100 messenger RNAs preferentially expressed in the niche encode surface receptors and secreted proteins, enabling LRCs to signal and respond to their environment. The study also revealed that the LRCs express a unique set of mRNAs compared to other SCs, including those from hematopoietic, embryonic, and neuronal tissues. These mRNAs include cell cycle regulatory proteins, Wnt pathway components, and secretory or integral membrane proteins, suggesting that the LRCs play a crucial role in maintaining and activating the niche. The findings provide insights into the specialized properties of the bulge SC niche and its interactions with LRCs.The study by Tudorita Tumbar and colleagues investigates the epithelial stem cell (SC) niche in the skin, focusing on the bulge region of hair follicles. They developed a method to fluorescently label slow-cycling cells, specifically label-retaining cells (LRCs), which are markers of the skin SC niche. These LRCs rarely divide within their niche but exhibit rapid proliferation and differentiation when stimulated to exit. The researchers characterized the transcriptional profile of these LRCs, finding that many of the >100 messenger RNAs preferentially expressed in the niche encode surface receptors and secreted proteins, enabling LRCs to signal and respond to their environment. The study also revealed that the LRCs express a unique set of mRNAs compared to other SCs, including those from hematopoietic, embryonic, and neuronal tissues. These mRNAs include cell cycle regulatory proteins, Wnt pathway components, and secretory or integral membrane proteins, suggesting that the LRCs play a crucial role in maintaining and activating the niche. The findings provide insights into the specialized properties of the bulge SC niche and its interactions with LRCs.