Trps1 Activates a Network of Secreted Wnt Inhibitors and Transcription Factors Crucial to Vibrissa Follicle Morphogenesis

The study investigated the role of the transcription factor Trps1 in vibrissa follicle morphogenesis, particularly in the context of trichorhinophalangeal syndrome types I and III, which involve sparse scalp hair. Researchers used mice with a deleted GATA domain in Trps1 (Trps1Δgt/Δgt) and found these mice had fewer pelage follicles and lacked vibrissae follicles postnatally. Through microarray analysis, they identified downregulated transcription factors and Wnt inhibitors, as well as upregulated extracellular matrix proteins in mutant embryos. The study revealed that Trps1 could directly bind to promoters to activate transcription, suggesting its role as a novel regulator of the Wnt signaling pathway and early hair follicle progenitors in vibrissa follicle development.