Figure 2: Model for the role of TLE3 in the bone marrow microenvironment. TLE3 directly induces adipogenesis and suppresses osteoblastogenesis of BMMSCs by acting on PPAR-γ and RUNX2, respectively. TLE3 also indirectly induces adipogenesis and suppresses osteoblastogenesis by repressing canonical Wnt signalling, which is capable of inducing osteoblastogenesis and inhibiting adipogenesis. In addition, canonical Wnt signalling induces TLE3 expression, suggesting that the induction of TLE3 by Wnt signalling may be part of a negative feedback loop during osteoblastogenesis and/or a positive feedback loop during adipogenesis in the adult bone marrow microenvironment. BMMSCs: bone marrow mesenchymal stem cells; OBs: osteoblasts; ADs: adipocytes.