TABLE 2.
The RXR AF-2 is necessary for full responsiveness of hRARα to natural and synthetic retinoidsa
| Ligand | Biological activity | Kd (RAR; nM) | EC50 (RAR/dnRXR; nM) | Relative potency (RAR/dnRXR; %) |
|---|---|---|---|---|
| atRA | RARα, -β, and -γ agonist | 3.3 | 8.70 | 46.0 |
| 9-cis RA | Panagonist | 7.1 | 12.60 | 55.4 |
| TTNPB | RARα, -β, and -γ agonist | 2.2 | 0.74 | 34.0 |
| CD367 | RARα, -β, and -γ agonist | 4.0 | 0.75 | 35.0 |
| Am580 | RARα agonist | 8.1 | 0.50 | 46.0 |
| CD3106 | RARα, -β, and -γ antagonist | 20.0 | NA | NA |
| CD2425 | RXRα, -β, and -γ agonist | >10,000 | ND | ND |
a
Features of retinoids are indicated as in Table 1. HeLa cells were transfected with hRARα and dnRXR expression vectors and the TREpal-TATA Luc reporter gene (26). EC50s and potency values were calculated as for Table 1 and deduced from dose-response curves as described above. NA, not detectable; ND, not determined.