Table 2.
Functional parameters of receptors containing one, or two, copies of each variant
| β3 Variants | Construct | Activation properties |
||
|---|---|---|---|---|
| I3mM GABA ± SEM (nA) | EC50 (μM)−logEC50 ± SEM | Est Po | ||
| WTa | γ2-β3-α1-β3-α1 | 2095 ± 126 (13)b | 69 (14) 4.11 ± 0.06 |
0.94 ± 0.03 (10) |
| γ2-β3-α5-β3-α5 | 808 ± 90 (20) | 108 (10) 3.93 ± 0.05 |
0.90 ± 0.01 (10) | |
| β3E77K | γ2-β3E77K-α1-β3-α1 | 1731 ± 241 (21) | 20 (10) 4.62** ± 0.07 |
0.98 ± 0.04 (10) |
| γ2-β3-α1-β3E77K-α1 | 1764 ± 245 (13) | 27 (10) 4.63** ± 0.06 |
1.02 ± 0.04 (10) | |
| γ2-β3E77K-α1-β3E77K-α1 | 946 ± 140 (16) | 21 (10) 4.69** ± 0.06 |
0.94 ± 0.04 (8) | |
| γ2-β3E77K-α5-β3E77K-α5 | 465 ± 66 (20) | 49 (10) 4.31*** ± 0.04 |
0.95 ± 0.05 (10) | |
| β3T287I | γ2-β3T287I-α1-β3-α1 | 1838 ± 310 (21) | 43 (10) 4.36 ± 0.08 |
0.97 ± 0.02 (10) |
| γ2-β3-α1-β3T287I-α1 | 1936 ± 316 (20) | 23 (10) 4.62** ± 0.12 |
0.93 ± 0.01 (11) | |
| γ2-β3T287I-α1-β3T287I-α1 | 2181 ± 223 (14) | 22 (10) 4.65** ± 0.06 |
1.00 ± 0.02 (10) | |
| γ2-β3T287I-α5-β3T287I-α5 | 712 ± 13 (20) | 45 (10) 4.30*** ± 0.08 |
1.01* ± 0.03 (10) | |
a
WT values except rate constants are also reported in Absalom et al. (2019).
b
Number of individual oocytes (n) are in parentheses.
*
P < 0.05.
**
P < 0.01.
***
P < 0.001, one-way ANOVA, Dunnett’s t-test c.f. WT.