| Construct . | pH50 . | n . | PNa+/PK+ . | PNa+/PLi+ . | PNa+/PCs+ . | n . |
|---|---|---|---|---|---|---|
| WT | 6.8 ± 0.0 | 5 | 8.0 ± 1.6 | 1.0 ± 0.2 | 29.7 ± 17.2 | 11 |
| W0′Nap | 6.4 ± 0.1a | 4 | 9.0 ± 1.7 | 1.1 ± 0.3 | n.d. | 5–7 |
| W0′L | 7.1 ± 0.0a | 4 | 1.2 ± 0.3a | 0.9 ± 0.2 | 1.2 ± 0.5a | 6 |
| W0′F | 7.3 ± 0.0a | 5 | 1.2 ± 0.2a | 0.8 ± 0.2 | 1.2 ± 0.2a | 6 |
| C3′L | 6.7 ± 0.0 | 5 | 6.8 ± 2.0 | 1.0 ± 0.2 | 22.6 ± 8.3 | 8–9 |
| F4′A | 6.8 ± 0.1 | 5 | 1.7 ± 0.6a | 1.5 ± 0.7 | 2.6 ± 1.2a | 30–33 |
| F4′L | 6.7 ± 0.0 | 5 | 3.4 ± 1.9a | 2.4 ± 2.8b | 3.9 ± 2.2a | 24–25 |
| F4′W | 6.8 ± 0.0 | 5 | 7.8 ± 2.2 | 1.5 ± 1.5 | 13.8 ± 6.4b | 23–24 |
| F4′Nap | n.d. | 9.3 ± 3.5 | 1.3 ± 0.4 | n.d. | ||
| G6′C | 6.6 ± 0.1c | 5 | 9.0 ± 1.8 | 1.3 ± 0.5 | 40.3 ± 11.4 | 13 |
| L8′F | 6.8 ± 0.0 | 5 | 8.0 ± 1.7 | 1.2 ± 0.3 | 38.1 ± 16.6 | 8–9 |
| V10′M | 6.9 ± 0.0b | 5 | 10.0 ± 3.3 | 1.3 ± 0.4 | 35.6 ± 18.1 | 8–17 |
| L12′Y | 6.7 ± 0.0 | 5 | 8.6 ± 2.1 | 1.0 ± 0.2 | 34.1 ± 10.3 | 11–13 |
| C13′W | 6.9 ± 0.1b | 7 | 7.4 ± 1.8 | 1.1 ± 0.3 | 29.3 ± 13.1 | 9 |
| V14′Q | 6.9 ± 0.0d | 5 | 8.7 ± 1.7 | 1.1 ± 0.2 | 29.8 ± 7.7 | 9 |
| C15′F | 6.5 ± 0.1a | 4 | 6.0 ± 1.6 | 1.4 ± 0.3 | 17.7 ± 4.8d | 31–34 |
| T16′G | 6.8 ± 0.1 | 5 | 8.0 ± 1.3 | 1.1 ± 0.3 | 25.2 ± 7.9 | 12–13 |
| E17′L | 6.9 ± 0.1b | 5 | 6.0 ± 1.8 | 1.2 ± 0.2 | 29.3 ± 10.4 | 10–16 |
| R18′L | 7.0 ± 0.1a | 5 | 8.5 ± 3.8 | 1.4 ± 0.4 | 31.9 ± 12.0 | 8–11 |
| V19′F | 6.8 ± 0.1 | 4 | 8.4 ± 0.7 | 1.2 ± 0.3 | 34.8 ± 7.6 | 8 |
| Q20′G | 6.7 ± 0.1 | 5 | 9.5 ± 2.8 | 1.3 ± 0.3 | 29.4 ± 17.1 | 14–16 |
| Y21′E | 6.8 ± 0.1 | 5 | 7.8 ± 3.2 | 1.2 ± 0.4 | 34.1 ± 18.4 | 12–14 |
| Y22′A | n.d. | n.d. | n.d. | n.d. | ||
| F23′A | 6.8 ± 0.0 | 5 | 9.0 ± 1.3 | 1.1 ± 0.3 | 55.0 ± 22.8 | 6–7 |
| Construct . | pH50 . | n . | PNa+/PK+ . | PNa+/PLi+ . | PNa+/PCs+ . | n . |
|---|---|---|---|---|---|---|
| WT | 6.8 ± 0.0 | 5 | 8.0 ± 1.6 | 1.0 ± 0.2 | 29.7 ± 17.2 | 11 |
| W0′Nap | 6.4 ± 0.1a | 4 | 9.0 ± 1.7 | 1.1 ± 0.3 | n.d. | 5–7 |
| W0′L | 7.1 ± 0.0a | 4 | 1.2 ± 0.3a | 0.9 ± 0.2 | 1.2 ± 0.5a | 6 |
| W0′F | 7.3 ± 0.0a | 5 | 1.2 ± 0.2a | 0.8 ± 0.2 | 1.2 ± 0.2a | 6 |
| C3′L | 6.7 ± 0.0 | 5 | 6.8 ± 2.0 | 1.0 ± 0.2 | 22.6 ± 8.3 | 8–9 |
| F4′A | 6.8 ± 0.1 | 5 | 1.7 ± 0.6a | 1.5 ± 0.7 | 2.6 ± 1.2a | 30–33 |
| F4′L | 6.7 ± 0.0 | 5 | 3.4 ± 1.9a | 2.4 ± 2.8b | 3.9 ± 2.2a | 24–25 |
| F4′W | 6.8 ± 0.0 | 5 | 7.8 ± 2.2 | 1.5 ± 1.5 | 13.8 ± 6.4b | 23–24 |
| F4′Nap | n.d. | 9.3 ± 3.5 | 1.3 ± 0.4 | n.d. | ||
| G6′C | 6.6 ± 0.1c | 5 | 9.0 ± 1.8 | 1.3 ± 0.5 | 40.3 ± 11.4 | 13 |
| L8′F | 6.8 ± 0.0 | 5 | 8.0 ± 1.7 | 1.2 ± 0.3 | 38.1 ± 16.6 | 8–9 |
| V10′M | 6.9 ± 0.0b | 5 | 10.0 ± 3.3 | 1.3 ± 0.4 | 35.6 ± 18.1 | 8–17 |
| L12′Y | 6.7 ± 0.0 | 5 | 8.6 ± 2.1 | 1.0 ± 0.2 | 34.1 ± 10.3 | 11–13 |
| C13′W | 6.9 ± 0.1b | 7 | 7.4 ± 1.8 | 1.1 ± 0.3 | 29.3 ± 13.1 | 9 |
| V14′Q | 6.9 ± 0.0d | 5 | 8.7 ± 1.7 | 1.1 ± 0.2 | 29.8 ± 7.7 | 9 |
| C15′F | 6.5 ± 0.1a | 4 | 6.0 ± 1.6 | 1.4 ± 0.3 | 17.7 ± 4.8d | 31–34 |
| T16′G | 6.8 ± 0.1 | 5 | 8.0 ± 1.3 | 1.1 ± 0.3 | 25.2 ± 7.9 | 12–13 |
| E17′L | 6.9 ± 0.1b | 5 | 6.0 ± 1.8 | 1.2 ± 0.2 | 29.3 ± 10.4 | 10–16 |
| R18′L | 7.0 ± 0.1a | 5 | 8.5 ± 3.8 | 1.4 ± 0.4 | 31.9 ± 12.0 | 8–11 |
| V19′F | 6.8 ± 0.1 | 4 | 8.4 ± 0.7 | 1.2 ± 0.3 | 34.8 ± 7.6 | 8 |
| Q20′G | 6.7 ± 0.1 | 5 | 9.5 ± 2.8 | 1.3 ± 0.3 | 29.4 ± 17.1 | 14–16 |
| Y21′E | 6.8 ± 0.1 | 5 | 7.8 ± 3.2 | 1.2 ± 0.4 | 34.1 ± 18.4 | 12–14 |
| Y22′A | n.d. | n.d. | n.d. | n.d. | ||
| F23′A | 6.8 ± 0.0 | 5 | 9.0 ± 1.3 | 1.1 ± 0.3 | 55.0 ± 22.8 | 6–7 |
Values are presented as mean ± SD, and n refers to the number of oocytes tested; n.d., not determined. The Y22′A mutant did not produce proton-gated currents. Values for the mutants were compared with WT and analyzed using one-way ANOVA with Dunnett’s multiple comparisons test.
P < 0.0001.
P < 0.01.
P < 0.001.
P < 0.05.