A Role for the TGF-β/BMP Co-Receptor Endoglin in the Molecular Oscillator That Regulates the Hair Follicle Cycle

The document from September 18, 2018, details a study on the role of Endoglin (Eng), a Tgf-β/Bmp co-receptor, in hair follicle cycling. The researchers used Eng haploinsufficient mice and found that Eng is essential for maintaining the correct hair follicle cycling pattern and stimulating hair follicle stem cell niches. They observed cyclic expression of Eng correlating with the hair cycle, with Eng haploinsufficient mice showing delayed entry into the hair cycle phases. The study also discovered that β-catenin binds to the Eng promoter in a Bmp signaling-dependent manner, and that β-catenin and Smad4 synergistically activate Eng promoter transcription. These findings suggest that Eng-dependent feedback between Wnt/β-catenin and Bmp/Smad signals may act as a molecular switch for the hair follicle growth/rest cycle. The altered hair follicle cycling was observed in 97% of analyzed animals (n=50).