Control of Hair Follicle Cell Fate by Underlying Mesenchyme Through a CSL–Wnt5a–FoxN1 Regulatory Axis
July 2010
in “
Genes & development
”
TLDR Notch/CSL signaling controls hair follicle differentiation through Wnt5a and FoxN1.
The study demonstrated that the maintenance of hair follicle keratinocyte cell fate was defective in mice with mesenchymal deletion of the CSL/RBP-Jκ gene, which is crucial for canonical Notch signaling. Hair follicle reconstitution assays indicated that this defect was due to an intrinsic issue in dermal papilla cells. Deletion of Wnt5a, a gene regulated by Notch/CSL in dermal papilla cells, resulted in similar hair follicle differentiation issues. Functional rescue experiments confirmed that Wnt5a was a critical downstream mediator of Notch–CSL signaling, affecting the expression of FoxN1 in keratinocytes, a gene essential for hair follicle regulation. Therefore, Notch/CSL signaling uniquely controlled hair follicle differentiation through Wnt5a and FoxN1.