Expression dynamics of lymphoid enhancer‐binding factor 1 in terminal Schwann cells, dermal papilla, and interfollicular epidermis

Background Transcription factor lymphoid enhancer‐binding factor 1 (LEF1) is a downstream mediator of the Wnt/β‐catenin signaling pathway. It is expressed in dermal papilla and surrounding cells in the hair follicle, promoting cell proliferation, and differentiation. Results Here, we report that LEF1 is also expressed all through the hair cycle in the terminal Schwann cells (TSCs), a component of the lanceolate complex located at the isthmus. The timing of LEF1 appearance at the isthmus coincides with that of hair follicle innervation. LEF1 is not found at the isthmus in the aberrant hair follicles in nude mice. Instead, LEF1 in TSCs is found in the de novo hair follicles reconstituted on nude mice by stem cells chamber graft assay. Cutaneous denervation experiment demonstrates that the LEF1 expression in TSCs is independent of nerve endings. At last, LEF1 expression in the interfollicular epidermis during the early stage of skin development is significantly suppressed in transgenic mice with T‐cell factor 3 (TCF3) overexpression. Conclusion We reveal the expression dynamics of LEF1 in skin during development and hair cycle. LEF1 expression in TSCs indicates that the LEF1/Wnt signal might help to establish a niche at the isthmus region for the lanceolate complex, the bulge stem cells and other neighboring cells. Key Findings LEF1 is expressed in the terminal Schwann cells (TSCs) surrounding the hair follicle isthmus. LEF1 expression in TSCs is independent of nerve endings. LEF1 expression in the interfollicular epidermis is suppressed by overexpression of TCF3. LEF1+ TSCs might constitute a Wnt‐active niche at the isthmus region.