摘要：SummaryThe Mammary gland undergoes complicated epithelial remodeling to form lobuloalveoli during pregnancy, in which basal epithelial cells remarkably increase to form a basket-like architecture. However, it remains largely unknown how dormant mammary basal stem/progenitor cells involve in lobuloalveolar development. Here, we show thatNfatc1expression marks a rare population of mammary epithelial cells with the majority being basal epithelial cells.Nfatc1reporter-marked basal epithelial cells are relatively dormant mammary stem/progenitor cells. AlthoughNfatc1reporter-marked basal epithelial cells have limited contribution to the homeostasis of mammary epithelium, they divide rapidly during pregnancy and contribute to lobuloalveolar development. Furthermore,Nfatc1reporter-marked basal epithelial cells are preferentially used for multiple pregnancies. Using single-cell RNA-seq analysis, we identify multiple functionally distinct clusters within theNfatc1reporter-marked cell-derived progeny cells during pregnancy. Taken together, our findings underscoreNfatc1reporter-marked basal cells as dormant stem/progenitor cells that contribute to mammary lobuloalveolar development during pregnancy.Graphical abstractDisplay OmittedHighlights•Nfatc1marked a subpopulation of basal dormant stem/progenitor cells•Nfatc1-marked cells have limited contribution to the homeostasis of mammary gland•Nfatc1reporter-marked cells divide rapidly during pregnancy•Nfatc1reporter-marked cells are preferentially used for multiple pregnanciesBiological sciences; Molecular physiology; Stem cells research; Omics
