A Niche Above: A Novel Modality of Stem Cell Regulation in Mammalian Skin Epidermis
March 2021
in “
Cell stem cell
”
keratinocytes epidermis stem/progenitor keratinocytes basal layer actomyosin contractility transgenic mouse models hair follicle lineage non-muscle myosin mechanical forces stem cell behavior skin cells skin layer stem cells base layer muscle contraction genetically modified mice hair growth myosin inhibitors physical forces stem cell activity
TLDR Skin cell behavior is influenced by the tightness of nearby cells, affecting their growth and development.
The study demonstrated that contractility in differentiating keratinocytes in the upper layers of the epidermis regulated the replication and differentiation of stem/progenitor keratinocytes in the basal layer. This finding expanded the understanding of the stem cell niche in skin, highlighting actomyosin contractility as a key component. Using transgenic mouse models, the researchers showed that increased contractility in differentiating keratinocytes led to increased proliferation in basal keratinocytes and altered lineage selection, diverting cells away from the hair follicle lineage. These effects were reversible with pharmacological inhibitors of non-muscle myosin, suggesting that mechanical forces from the upper layers influence stem cell behavior in the basal layer. This research provided significant insights into the regulation of stem cells in the epidermis and raised new questions about the specific mechanisms involved.
