The Basement Membrane Of Hair Follicle Stem Cells Is A Muscle Cell Niche

The study demonstrated that nephronectin, a target gene of Wnt/β-catenin signaling, played a crucial role in anchoring arrector pili muscles (APM) to the hair follicle bulge by facilitating the adhesion of α8β1 integrin-expressing mesenchymal cells. In nephronectin knockout mice, the absence of nephronectin led to a shift in APM attachment from the bulge to a higher region of the follicle, indicating a compensatory mechanism involving EGFL6. The study highlighted the importance of nephronectin-α8β1 interactions in creating a niche for APM cells and provided insights into the mechanism of APM morphogenesis and its attachment to the hair follicle bulge.