Binding of [3H]NMS to m1 mAChRs mutated at Asp122 or Tyr124
| Mutant | pKd 1-a | Relative value1-b |
|---|---|---|
| −log (m) | % Wild-type | |
| Wild-type | 10.0 ± 0.1 | (100) |
| D122E | 10.0 ± 0.1 | 10 ± 1 |
| D122N | 10.2 ± 0.1 | 10 ± 2 |
| D122H | 10.0 ± 0.1 | 30 ± 3 |
| D122A | 0 | |
| D122S | 1 | |
| D122C | 0 | |
| D122L | 0 | |
| D122K | 0 | |
| Y124F | 10.0 ± 0.1 | 78 ± 4 |
| Y124W | 9.9 ± 0.1 | 43 ± 2 |
| Y124H | 10.1 ± 0.1 | 5 ± 1 |
| Y124M | 10.1 ± 0.2 | 3 ± 1 |
| Y124C | 10.0 ± 0.2 | 4 ± 1 |
| Y124I | 0 | |
| Y124R | 0 | |
| Y124E | 0 |
Expression of the wild-type receptor varied over a 2.4-fold range (1.15 ± 0.39 pmol/mg, mean ± standard deviation; 15 experiments). Expression of mutant receptors varied in proportion (e.g., expression of Asp122Asn was 11% of wild-type at 0.86 pmol/mg and 10% at 2.1 pmol/mg).