A Niche Above: A Novel Modality of Stem Cell Regulation in Mammalian Skin Epidermis

In this issue of Cell Stem Cell, Ning et al. (2021) demonstrate that contractility in differentiating, suprabasally located keratinocytes acts non-cell-autonomously to regulate the replication and differentiation of the stem/progenitor keratinocytes in the basal layer of epidermis. This finding expands our understanding of the niche that regulates stem/progenitor cells in skin.