Understanding the role of Ror2-dependent pathway(s) in adult hair follicle stem cells

Research addressing how Wnt signaling modulates the behaviors of Stem Cells (SCs) has largely focused on β-catenin-dependent canonical Wnt pathway, and very limited information can be found about β-catenin-independent signaling in the SC niche. In this doctoral research, hair follicle (HF) is used as a model system to study the role of Ror2, a non-canonical Wnt receptor, in adult HFSCs. We uncovered that Ror2-dependent signaling is upregulated in activated HFSCs in vivo. Using a loss-of-function approach, we demonstrated that Ror2 is indispensable for HFSC self-renewal and long-term maintenance. We not only confirmed the classical role of Ror2 in mediating Wnt5a-dependent signaling and cell migration, but also uncovered novel functions of Ror2 in regulation of cell proliferation and maintenance of HFSC identity. Finally, we unveiled a compensatory mechanism mediated by Ror2-PKC signaling that keeps stemness of β-catenin-null HFSCs and prevent their loss from differentiation towards wrong fate.(BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 201