The Role of Fgf20 in Establishing the Hair Follicle Dermal Condensate

The document reports on a study investigating the role of Fgf20 in the development of the hair follicle dermal condensate (DC), which is crucial for hair follicle morphogenesis and the regulation of hair growth cycles. The study utilized RNA sequencing, organ culture, and live tissue imaging to explore the molecular and cellular responses to Fgf20 signaling and the events leading to DC development. The findings indicate that Fgf20 promotes fibroblast migration and induces the expression of some DC markers. The cells that form the DC, identified by Sox2 expression, do not originate from a pre-existing Sox2+ cell population but rather exit the cell cycle and migrate to form the DC. These cells also adopt a convex shape early in hair follicle morphogenesis, which can be induced by local FGF20 administration ex vivo. Modulation of FGF signaling is critical for the attraction and maintenance of DC cells. The study concludes that Fgf20 plays a significant role in the cellular and molecular regulation of DC morphogenesis.