[Hereditary skeletal dysplasias and FGFR3 and PTHR1 signaling pathways]

Skeletal development is a highly sophisticated process involving, as a first step, migration and condensation of mesenchymal cells into osteoprogenitor cells. These cells further differentiate into chondrocytes and osteoblasts through multiple differentiation stages requiring a set of specific transcriptional factors. Defective endochondral ossification in human is associated with a large number of inherited skeletal dysplasias caused by mutations in genes encoding extracellular matrix components, growth factors and their receptors, signaling molecules and transcription factors. This review summarizes some of the recent findings on a series of chondrodysplasias caused by mutations in FGFR3 and PTHR1, two receptors expressed in the cartilage growth plate and mediating two main signaling pathways. Data from human diseases and relevant animal models provide new clues for understanding how signaling molecules and their interaction with key transcription factors control and regulate the development and growth of long bones.