TCF is a family of DNA binding proteins, which are participating in the overall embryo development and in particular in epithelium's development. The member of TCF family, TCF3, works together with WNT signalling in order gastrulation to proceed. However, it was thought that after development TCF3 remains only as marker of follicle stem cells and works only with combination with WNT-signaling pathway during wounding, induces the epidermis to undergo de novo hair follicle morphogenesis.
Recently the team of Dr. Nguen from the Rockefeller University Tcf3 and Tcf4 are the key transcription factors to maintain long-term epidermal homeostasis. Overall, Tcf3 and Tcf4 may be essential for establishing and maintaining all skin epithelial stem cells through Wnt-dependent and Wnt-independent roles.
Source: Nature Genetics