Guides: Open Access: Learn More

The study demonstrated that the Vitamin D receptor (VDR) was crucial for maintaining hair follicle homeostasis, as its absence led to hair loss in <i>Vdr</i>-knockout mice by halting the hair cycle during the catagen stage, which precedes alopecia. In these mice, epithelial strands that should regress during catagen persisted as "surviving epithelial strands," formed by cells in the lower hair follicle, as revealed by single-cell RNA sequencing. These findings highlighted the significance of the regression phase in hair follicle regeneration and identified VDR as a key regulator of the catagen stage.