Figure 4.

Molecular regulation of chondrogenesis. MSCs are recruited to the future sites of cartilage formation. Following migration and local proliferation cell density increases (condensation). Cell-cell contacts trigger a set of intracellular signaling events which result in chondrogenesis accompanied by a change in cell morphology and cartilage ECM molecule secretion. A wide range of transcription factors regulated by soluble extracellular signaling molecules acting through the modulation of various protein kinases/phosphoprotein phosphatases play essential roles in the molecular control of chondrogenesis. See further details in text. Please note that this list is not exhaustive.