Table 2.
Current density and V1/2 in homomeric and heteromeric transfected HEK293 cell in the variants of S247X, S247L S247W, and P285T.
| N | V1/2 (mV) (mean ± SD) | K (slope) (mean ± SD) | Current densities (pA/pF) (mean ± SD) | Ratio of variants to WT current density (%) | |
|---|---|---|---|---|---|
| KCNQ2 WT† (2 ug) | 20 | − 16.2 ± 2.3 | 9.4 ± 1.6 | 564.4 ± 49.9 | 100.0 |
| Nontransfected HEK293 cell | 5 | − 5.2 ± 2.8* | 2.6 ± 0.5** | 213.5 ± 45.4** | 37.8 |
| S247L (2 ug) | 10 | − 12.1 ± 1.7*& | 6.9 ± 1.9*& | 419.2 ± 56.5*& | 74.3 |
| S247X (2 ug) | 10 | − 5.1 ± 3.6* | 3.1 ± 1.3** | 234.7 ± 35.8** | 41.6 |
| S247W (2 ug) | 10 | − 10.9 ± 3.0*% | 5.7 ± 1.2**% | 395.7 ± 40.0*% | 70.1 |
| P285T (2 ug) | 10 | − 13.8 ± 3.2@ | 7.9 ± 0.9*@ | 436.0 ± 55.0*@ | 77.2 |
| KCNQ2 WT + S247L (1ug:1 ug) | 10 | − 13.3 ± 0.7*& | 7.8 ± 1.2*& | 485.4 ± 24.5*& | 86.0 |
| KCNQ2 WT + S247X (1ug:1 ug) | 10 | − 16.5 ± 1.0 | 9.1 ± 1.2 | 538.4 ± 31.4 | 95.4 |
| KCNQ2 WT + S247W (1ug:1 ug) | 10 | − 12.8 ± 0.8*% | 6.3 ± 1.5**% | 471.4 ± 33.4*% | 83.5 |
| KCNQ2 WT + P285T (1ug:1 ug) | 10 | − 14.8 ± 2.1 | 8.8 ± 1.5 | 518.0 ± 24.5 | 91.8 |
| KCNQ2 WT + KCNQ3 WT# (1ug:1 ug) | 10 | − 20.8 ± 1.6 | 14.9 ± 3.0 | 813.9 ± 118.3 | 100.0 |
| KCNQ2 WT + S247L + KCNQ3 WT (0.5 ug:0.5 ug:1 ug) | 10 | − 17.9 ± 0.9*& | 12.1 ± 2.2 | 691.7 ± 51.4 | 85.0 |
| KCNQ2 WT + S247X + KCNQ3 WT (0.5 ug:0.5 ug:1 ug) | 10 | − 20.37 ± 2.7 | 13.3 ± 1.8 | 788.9 ± 86.0 | 96.9 |
| KCNQ2 WT + S247W + KCNQ3 WT(0.5 ug:0.5 ug:1 ug) | 10 | − 17.3 ± 1.4*% | 10.7 ± 1.2**% | 666.9 ± 41.2*% | 81.9 |
| KCNQ2 WT + P285T + KCNQ3 WT (0.5 ug:0.5 ug:1 ug) | 9 | − 18.8 ± 2.2 | 12.9 ± 1.8 | 705.2 ± 53.3 | 86.6 |
Data rounded off to the first decimal place.
WT, wild type; V is the test potential; V½, half-maximal activation voltage; SD, standard deviation.
The data were then fit to a Boltzmann distribution of the following form: G/Gmax = 1/(1 + exp[(V − V½)/dx]).
†The current densities in the homomeric transfected variants and heteromeric transfected KCNQ2 WT + variants were compared with the current density in KCNQ2 WT (2 ug) respectively.
#The current densities in the heteromeric KCNQ2 WT + KCNQ3 WT + variants were compared with the current density in KCNQ2 WT + KCNQ3 WT (1ug:1 ug) respectively.
*p < 0.05 compared with WT; **, p < 0.005; bold font indicates significantly different from WT.
&p < 0.05 in homomeric S247L versus homomeric S247X or heteromeric S247L versus heteromeric S247X respectively.
%p < 0.05 in homomeric S247W versus homomeric S247X or heteromeric S247W versus heteromeric S247X respectively.
@p < 0.05 in homomeric P285T versus homomeric S247X or heteromeric P285T versus heteromeric S247X respectively.