Table 1. Binding affinity of S100B and S100A4 for p53CT and p53CT-derived peptides by using fluorescence anisotropy.
|
Kd, μM
|
||
|---|---|---|
| Peptide (residues) | S100B | S100A4 |
| NLS (305-322) | n.q. | n.d. |
| N-tet (325-339) | 172 ± 4 | 150 ± 4 |
| NES (340-351) | 302 ± 7 | 135 ± 3 |
| TET (325-355) | 112 ± 7 | 17 ± 1 |
| NRD (367-393) | 102 ± 3 | n.q. |
| p53CT (293-393) | 0.25 ± 0.05 | 10 ± 2* |
| 16 ± 2 | 50 ± 1 | |
Experiments were carried out by using peptide at a concentration of 0.5 μM, with the exception of TET and p53CT, which were used at 0.1 μM. Values were obtained by fitting the binding data to a single-site model, with the exception of TET data, which fit to a single-site model plus a linear drift, and p53CT data, which fit to a two-site model. n.q., not quantifiable although detectable; n.d., not detectable.
*
Kd values for S100A4 binding to p53CT were obtained by fitting the change in total fluorescence.