• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <0.1 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its ability to inhibit FGF acidic-dependent proliferation of NR6R?3T3 mouse fibroblast cells. The ED    ₅₀ for this effect is 1?3 ng/mL.

• Source

  Mouse myeloma cell line, NS0-derived

  Human FGF R3 (IIIc) (Glu23-Gly375) Accession # P22607	IEGRMD	Human IgG1 (Pro100-Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Glu23

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  64.7 kDa (monomer)

• SDS-PAGE

  95-105 kDa, reducing conditions

Background: FGF R3

Fibroblast growth factors (FGFs) comprise a family of at least eighteen structurally related proteins that are involved in a multitude of physiological and pathological cellular processes, including cell growth, differentiation, angiogenesis, wound healing and tumorgenesis. The biological activities of the FGFs are mediated by a family of type I transmembrane tyrosine kinases which undergo dimerization and autophosphorylation after ligand binding. Four distinct genes encoding closely related FGF receptors, FGF R1-4, are known. All four genes for FGF Rs encode proteins with an N-terminal signal peptide, three immunoglobulin (Ig)-like domains, an acid?box region containing a run of acidic residues between the IgI and IgII domains, a transmembrane domain and the split tyrosine-kinase domain. Multiple forms of FGF R1?3 are generated by alternative splicing of the mRNAs. A frequent splicing event involving FGF R1 and 2 results in receptors containing all three Ig domains, referred to as the alpha  isoform, or only IgII and IgIII, referred to as the beta  isoform. Only the alpha  isoform has been identified for FGF R3 and FGF R4. Additional splicing events for FGF R1-3, involving the C-terminal half of the IgIII domain encoded by two mutually exclusive alternative exons, generate FGF receptors with alternative IgIII domains (IIIb and IIIc). A IIIa isoform which is a secreted FGF binding protein containing only the N-terminal half of the IgIII domain plus some intron sequences has also been reported for FGF R1. Mutations in FGF R1-3 have been found in patients with birth defects involving craniosynostosis. The complex patterns of expression of these receptors as well as the specificity of their interactions with the various FGF ligand family members are under investigation.

• References:

1. Galzie, Z. et al. (1997) Biochem. Cell Biol. 75:669.

2. Burke, D. et al. (1998) Trends Biochem. Sci. 23:59.

• Long Name:

  Fibroblast Growth Factor Receptor 3

• Entrez Gene IDs:

  2261 (Human); 14184 (Mouse)

• Alternate Names:

  CD333; CEK; EC 2.7.10; FGF R3; FGFR3; fibroblast growth factor receptor 3; HSFGFR3EX; JTK4; JTK4thanatophoric dwarfism