Table 1.
Comparison of the binding of WW1 domain to various PPXY-containing peptides derived from putative ligands of WWOX alone (WW1) and in the context of WW1-WW2 tandem module (WW1-WW2) in terms of the apparent equilibrium dissociation constant (Kd)
| Kd / μM | |||
|---|---|---|---|
| Ligand | Peptide Sequence | WW1 | WW1-WW2 |
| ErbB4 | TVLPPPPYRHRN | 179 ± 10 | 75 ± 8 |
| p73 | HCTPPPPYHADP | 107 ± 9 | 60 ± 6 |
| PTCH1 | RYSPPPPYSSHS | 278 ± 19 | 79 ± 8 |
| PTPN14 | LFRPPPPYPRPR | 763 ± 62 | 214 ± 30 |
| SMAD7 | LESPPPPYSRYP | 272 ± 29 | 53 ± 8 |
| TMG2 | HDAPPPPYTSLR | 202 ± 23 | 84 ± 9 |
| WBP1 | PGTPPPPYTVAP | 368 ± 44 | 141 ± 12 |
| WBP2 | SQPPPPPYYPPE | 133 ± 18 | 42 ± 7 |
Note that the consensus residues within the PPXY motif of each peptide are colored red for clarity. All parameters were obtained from isothermal titration calorimetry (ITC) measurements conducted at 25°C and pH 7. Errors were calculated from at least three independent measurements to one standard deviation.