FGFR3 cross-linked fractions in the absence of ligand and in the presence of 2500 ng/ml (158 nM) fgf1.

Data are averages and standard errors from 3 independent experiments, conducted under the transfection conditions used to measure activation. Dimeric receptors were cross-linked with the membrane impermeable crosslinker BS3. The increase in cross-linking due to the mutation in the absence of fgf1 is about 75% and is statistically significant (p = 0.014). In unpublished work, we see the same increase in dimerization using FRET. The mutation does not have a significant effect on cross-linking at high fgf1 concentrations (p = 0.21). aData from [20].