Ligand binding studies for the combination proline-to-alanine mutations.
| Iloprost | Carbacyclin | PGE1 | Expression | |
|---|---|---|---|---|
| nM | nM | nM | pmol/mg protein | |
| hIP1D4PMT4 (WT) | 7 ± 3 | 121 ± 51 | 301 ± 90 | 2.1 ± 0.5 |
| P17A/P179A | 38 ± 5 | 267 ± 71 | 890 ± 121 | 1.2 ± 0.3 |
| P69A/P89A | 33 ± 7 | 265 ± 56 | 548 ± 144 | 1.2 ± 0.3 |
| P141A/P285A | 16 ± 2 | 177 ± 34 | 842 ± 143 | 3.9 ± 1.5 |
| P17A/P69A/P89A | >5003-150 | N.D. | N.D. | 0.4 ± 0.1 |
| P141A/P179A/P285A | >5003-150 | N.D. | N.D. | 0.6 ± 0.2 |
Shown are K i values (mean ± S.E.) from at least three separate experiments (duplicates of 12 different concentrations). Receptor expressions were determined by saturation binding from membranes prepared from COS-1 cells transfected with 20 μg of DNA per plate.
N.D., not determined.
↵3-150 p < 0.001.