Table 2.

Biophysical properties of wild-type and mutant K_v7.2 channels in GFP-cotransfected CHO hm1 cells in the presence or absence of diC8-PIP₂.

Transfection	n	Leak substracted peak current (pA)	V1/2 (mV)	k (mV/efold)	Iinstant / Isteady-state	Tau activation at +20 mV (ms)
GFP + Kv7.2 WT	11	321.4 ± 38.5	−8.0 ± 0.6	10.6 ± 0.5	0.14 ± 0.02	79.4 ± 4.8
GFP + Kv7.2 A343D	12	15.6 ± 1.8*	−45.2 ± 3.3*	11.3 ± 2.5	1.00 ± 0.04*	4.9 ± 0.6*
GFP + Kv7.2 R333W	12	241.7 ± 35.5	−8.2 ± 1.1	12.5 ± 1.1	0.26 ± 0.02*	90.3 ± 6.3
GFP + Kv7.2 M518V	8	29.5 ± 8.2*	−32.9 ± 3.6*	10.2 ±1.5	0.89 ± 0.09*	5.2 ± 0.9*
GFP + Kv7.2 K526N	14	430.0 ± 72.2	−7.9 ± 0.9	14.5 ± 0.7*	0.11 ± 0.02	86.3 ± 2.9
GFP + Kv7.2 R532W	18	184.8 ± 30.5	−7.2 ± 1.4	12.2 ± 1.1	0.31 ± 0.04*	112.8 ± 7.2*
GFP + Kv7.2 WT + diC8-PIP2	8	638.4 ± 66.2‡	−6.4 ± 1.2	15.0 ± 0.5†	0.12 ± 0.02	79.7 ± 5.4
GFP + Kv7.2 R333W + diC8-PIP2	13	404.8 ± 54.6†	−7.9 ± 1.2	15.2 ± 1.0‡	0.19 ± 0.02‡	86.2 ± 2.9
GFP + Kv7.2 K526N + diC8-PIP2	14	1276.5 ± 140.8†‡	−5.3 ± 1.3‡	14.2 ± 0.8‡	0.07 ± 0.01‡	58.3 ± 2.4†‡
GFP + Kv7.2 R532W + diC8-PIP2	11	258.0 ± 31.3†	−5.6 ± 0.9	17.2 ± 2.6‡	0.21 ± 0.05†‡	100.3 ± 5.1‡

n, number; Leak subtracted peak current measured at +20 mV; V_1/2, half-activation potential calculated using leak subtracted currents; k, the slope factor calculated using leak subtracted currents; I_instant, leak subtracted current measured at the beginning of the depolarization step; I_steady-state, leak subtracted current measured at the end of the 0 mV depolarization; τ, activation time constant measured at + 20 mV using leak subtracted currents. Ave ± SEM (*p<0.05 for comparing K_v7.2 wild-type (WT) vs. mutants; †p<0.05 for comparing K_v7.2 WT + diC8-PIP₂. vs mutants + diC8-PIP_2; ‡p<0.05 comparing for K_v7.2 wild-type (WT) vs mutants + diC8-PIP₂). Each value represents the Ave ± SEM.