Human Fibroblast Growth Factor Receptor 3 (FGFR3) Protein

Background

Fibroblast growth factor receptor 3 (FGFR3) FGFR3 is a transmembrane tyrosine kinase receptor that mediates fibroblast growth factor (FGF) signaling, playing critical roles in skeletal development, cartilage maintenance, and cell proliferation. Structurally, FGFR3 comprises an extracellular ligand-binding domain with three immunoglobulin-like loops, a single transmembrane domain, and an intracellular kinase domain that transduces signals upon ligand-induced dimerization and autophosphorylation. FGFR3 is highly expressed in cartilage, where it regulates chondrocyte differentiation and proliferation. Gain-of-function mutations in FGFR3 are associated with skeletal dysplasias such as achondroplasia and thanatophoric dysplasia, characterized by impaired bone growth due to excessive inhibition of chondrocyte proliferation. Additionally, FGFR3 is implicated in cancer, including bladder cancer and multiple myeloma, where aberrant activation of FGFR3 signaling promotes cell proliferation and survival. FGFR3’s regulatory roles in growth plate development and oncogenesis highlight its dual importance in development and disease pathology.