TABLE 2.
Summary of functional assays in the tested mutants
A cAMP inhibition assay was used to measure the potencies (pEC50 ± S.E.) of the tested ligands at the different mutants (n = 3–5). ND, not determined.
| KOR variant | Salvinorin A | U-96593 | Dynorphin A(1–17) | 1xx |
|---|---|---|---|---|
| WT | 9.87 ± 0.05 | 8.49 ± 0.08 | 8.32 ± 0.06 | 7.29 ± 0.09 |
| Y66A (1.38) | 9.01 ± 0.05 | 7.75 ± 0.05 | 7.98 ± 0.06 | 6.81 ± 0.04 |
| Q115A (2.60) | 8.58 ± 0.05 | 8.5 ± 0.04 | 7.19 ± 0.06 | 7.14 ± 0.05 |
| Y119A (2.64) | 8.41 ± 0.04 | 8.04 ± 0.05 | 7.26 ± 0.06 | 6.23 ± 0.04 |
| Y119F (2.64) | 9.28 ± 0.03 | 8.09 ± 0.06 | 8.42 ± 0.04 | 6.86 ± 0.04 |
| I135A (3.29) | 8.06 ± 0.04 | 7.14 ± 0.04 | 7.67 ± 0.04 | 5.78 ± 0.05 |
| D138A (3.32) | 9.6 ± 0.13 | ND | ND | 7.44 ± 0.09 |
| D138N (3.32) | 10.6 ± 0.03 | 5.16 ± 0.25 | 5.72 ± 0.05 | 8.04 ± 0.05 |
| Y139A (3.33) | 8.14 ± 0.05 | 7.55 ± 0.07 | 6.93 ± 0.04 | 6.4 ± 0.07 |
| Y139F (3.33) | 9.72 ± 0.04 | 8.48 ± 0.04 | 7.65 ± 0.06 | 6.86 ± 0.05 |
| M142A (3.36) | 7.77 ± 0.04 | 7.71 ± 0.04 | 6.97 ± 0.05 | 7.55 ± 0.04 |
| K200A (ECL2) | 10.03 ± 0.03 | 8.9 ± 0.03 | 8.8 ± 0.03 | 7.1 ± 0.03 |
| L212A (ECL2) | 8.21 ± 0.04 | 7.78 ± 0.04 | 7.1 ± 0.04 | 5.88 ± 0.04 |
| M226A (5.38) | 10.43 ± 0.05 | 9.73 ± 0.05 | 8.86 ± 0.05 | 7.37 ± 0.05 |
| K227A (5.39) | 9.29 ± 0.03 | 8.38 ± 0.03 | 7.93 ± 0.06 | 6.65 ± 0.07 |
| H291A (6.52) | 8.14 ± 0.06 | 6.87 ± 0.06 | 6.58 ± 0.07 | 6.05 ± 0.08 |
| H291F (6.52) | 8.79 ± 0.04 | 8.37 ± 0.04 | 7.09 ± 0.04 | 6.64 ± 0.04 |
| I294A (6.55) | 10.06 ± 0.06 | 8.33 ± 0.08 | 7.14 ± 0.05 | 6.46 ± 0.07 |
| E297A (6.58) | 9.93 ± 0.03 | 8.93 ± 0.04 | 7.36 ± 0.04 | 7.19 ± 0.04 |
| Y312A (7.35) | 8.21 ± 0.04 | 7.19 ± 0.03 | 7.33 ± 0.04 | 6.44 ± 0.05 |
| Y312F (7.35) | 9.56 ± 0.03 | 8.25 ± 0.04 | 8.24 ± 0.04 | 7.15 ± 0.05 |
| Y313A (7.36) | 8.05 ± 0.04 | 8.38 ± 0.05 | 7.52 ± 0.04 | 6.49 ± 0.06 |
| Y313F (7.36) | 9.55 ± 0.04 | 8.32 ± 0.03 | 8.23 ± 0.06 | 7.24 ± 0.07 |
| I316A (7.39) | 6.6 ± 0.11 | 7.72 ± 0.05 | 6.9 ± 0.05 | 6.4 ± 0.04 |
| Y320A (7.43) | 6.45 ± 0.05 | 6.08 ± 0.1 | 7 ± 0.08 | ND |
| Y320F (7.43) | 7.67 ± 0.05 | 6.81 ± 0.05 | 7.12 ± 0.04 | 6.6 ± 0.07 |