TABLE 2.
Biophysical properties of human KV2.1 alone or coexpressed with WT or mutant human KCNE5
| Subunits | Activation |
Inactivation |
Deactivation |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|
| V 1/2 | k | τ (at +60 mV) | n | V 1/2 | k | n | τ1 (at −40 mV) | τ2 (at −40 mV) | n | |
| KV2.1 | 0.0 ± 1.9 | 9.4 ± 0.5 | 15.7 ± 1.6 | 6 | −26.5 ± 1.6 | 5.2 ± 0.5 | 5 | 15.3 ± 1.1 | 73.1 ± 11.1 | 4 |
| KV2.1+ | ||||||||||
| WT | 1.3 ± 2.2 | 9.7 ± 0.7 | 17.4 ± 0.9 | 7 | −24.3 ± 2.8 | 5.7 ± 0.2 | 8 | 15.6 ± 1.0 | 61.4 ± 5.1 | 8 |
| P33S | −0.2 ± 2.5 | 10.0 ± 1.1 | 16.0 ± 1.2 | 6 | −23.9 ± 2.1 | 5.6 ± 0.4 | 6 | 16.2 ± 2.6 | 68.0 ± 7.6 | 5 |
| L65F | −10.4 ± 2.4 | 9.1 ± 1.3 | 13.9 ± 1.1 | 7 | −34.8 ± 3.3 | 5.6 ± 0.2 | 7 | 17.0 ± 1.1 | 75.3 ± 5.2 | 4 |
| R85H | 7.0 ± 1.8 | 10.4 ± 1.0 | 16.4 ± 0.7 | 6 | −24.1 ± 2.4 | 6.4 ± 0.3 | 6 | 16.0 ± 1.1 | 63.9 ± 7.7 | 5 |
| Y81H | −2.4 ± 2.1 | 9.6 ± 0.6 | 14.8 ± 0.3 | 6 | −26.9 ± 3.9 | 5.4 ± 0.3 | 5 | 18.0 ± 1.5 | 67.2 ± 10.7 | 6 |
| D92E/E93X | −5.2 ± 1.4 | 8.8 ± 0.5 | 13.4 ± 0.9 | 7 | −26.4 ± 1.3 | 5.8 ± 0.3 | 5 | 16.3 ± 1.8 | 84.4 ± 3.5 | 5 |
Values are means ± sem. V1/2, midpoint (mV) of activation or inactivation; k, slope factor; τ, time constant (ms); n, number of cells. Values underlined showed a statistically significant difference compared to KV2.1+KCNE5 values. P < 0.05.