Table 1.
Basal signaling activity and stimulation of Gq/11 and G12/13 pathways with 3-T1AM and PEA at TAAR8 and Taar8b. Cells over-expressing TAAR8 and Taar8b were stimulated with either 10 µM 3-T1AM or 10 µM PEA. Values represent luciferase activities (IP3–luc, RhoA–luc) and are indicated as mean ± SEM relative light units (rlu) in fold over basal or ligand-stimulated mock, each based on three to five independent experiments performed in triplicate. Mock transfected cells showed basal levels of 5003 ± 930 rlu for IP3-luc and 209,855 ± 27,087 rlu for RhoA-luc. The human thyrotropin receptor (TSHR) served as a positive control. Cells transfected with TSHR demonstrated basal levels of 3442 ± 589 rlu (IP3–luc) or 435,437 ± 70,197 rlu (RhoA–luc). Stimulation of TSHR was found to be within a range of 64.4 ± 13.0 rlu (IP3–luc) or 17.4 ± 4.7 rlu (RhoA–luc) fold over basal mock.
| TAAR Subtype | Second Messenger Signaling | Ligand | Basal Activity (Fold Over Basal Mock) | Ligand Stimulated (Fold Over Stimulated Mock) |
|---|---|---|---|---|
| TAAR8 | IP3–luc | 3-T1AM | 1.6 ± 0.1 | 1.1 ± 0.2 |
| PEA | 1.1 ± 0.2 | |||
| RhoA–luc | 3-T1AM | 1.2 ± 0.1 | 1.5 ± 0.3 | |
| PEA | 1.2 ± 0.1 | |||
| Taar8b | IP3–luc | 3-T1AM | 1.2 ± 0.1 | 0.9 ± 0.1 |
| PEA | 1.4 ± 0.2 | |||
| RhoA–luc | 3-T1AM | 1.0 ± 0.1 | 0.8 ± 0.1 | |
| PEA | 0.9 ± 0.1 |