Chondrocyte fate determination and maintenance requires Sox9, an intrinsic transcription
factor, but is inhibited by Wnt/β-catenin signaling activated by extrinsic Wnt ligands. Here we
explored the underlying molecular mechanism by which Sox9 antagonizes the Wnt/β-
catenin signaling in chondrocyte differentiation. We found that Sox9 employed two distinct
mechanisms to inhibit Wnt/β-catenin signaling: the Sox9 N terminus is necessary and
sufficient to promote β-catenin degradation, whereas the C terminus is required to inhibit β …