TABLE 2.
Summary of DNA synthesis activity and receptor binding affinity of mutant FGF4
| Protein (Gly79-Leu206) | DNA synthesis (ED50 for mutant/ED50 for wild type)a
|
Receptor binding (IC50 for mutant/IC50 for wild type)b (+ heparin) | |
|---|---|---|---|
| −Heparin | +Heparin | ||
| Wild type | 1 | 1 | 1 |
| Y87A | >500 | 500 | >100 |
| F129A | >500 | >500 | >100 |
| F151A | 1,000 | 4 | 2.5 |
| E159A | >1,000 | 80 | 5.0 |
| Y166A | 500 | >500 | >100 |
| L203A | >500 | >500 | >100 |
| R205A | 25 | 2.5 | 2.5 |
| N89A/K198A | 10 | 10 | NDc |
| K183A/K188A | 70 | 13 | ND |
| R103A/K144A | 1 | 1 | ND |
a
ED50, 50% effective dose, defined as the dose of FGF4 necessary to reach 50% of maximum DNA synthesis obtained with the wild-type FGF4.
b
IC50, 50% inhibitory concentration, defined as the concentration of FGF4 required to compete 50% of binding of labeled wild-type FGF4 to FGFR2.
c
ND, not determined.