Figure 3.

Elevated FGF signaling is critical for the pathogenesis of the dwarfism developed in EVC. (A) In control growth plate, both Hedgehog signaling (yellow-green feedback loop) and FGF signaling (red) work on chondrocytes to ensure regulated proliferation and maturation. (B) In Evc2/Limbin mutant growth plate, moderately decreased Hedgehog signaling due to Evc2/Limbin loss of function within only chondrocytes moderately contributes to the pathogenesis of dwarfism, whereas elevated FGF signaling due to loss of Evc2/Limbin within perichondrium critically contributes the pathogenesis of the dwarfism. Green, resting chondrocytes; gold sand, proliferating chondrocytes; aqua, hypertrophic chondrocytes, IHH, Indian Hedgehog ligand.