TABLE 1.

Summary of parameters of gating in P-segment mutants

Values are presented as mean ± S.E.M.

	Activation Curve		Steady-State Inactivation Curve		Recovery from Fast Inactivation (10 ms)	T1/2 of Inactivation at 0 mV	n
	V1/2	k	V1/2′	K′
	mV		mV			ms
WT	−18.7 ± 2.1	7.8 ± 0.6	−65.6 ± 1.6	7.6 ± 0.7		0.32 ± 0.02	7
Domain I
Q399C	−17.8 ± 2.0	8.4 ± 0.6	−56.1 ± 2.4*	6.0 ± 1.2	N.C.	0.32 ± 0.02	12
T398C	−22.7 ± 1.5	7.3 ± 0.6	−58.7 ± 1.8*	6.7 ± 0.6	N.C.	0.30 ± 0.02	11
M397C	−20.9 ± 3.8	7.4 ± 0.7	−58.8 ± 2.1*	7.7 ± 1.2	N.C.	0.31 ± 0.02	5
L396C	−34.2 ± 2.6*	3.4 ± 0.8*	−53.2 ± 2.4*	5.8 ± 0.7	N.C.	0.57 ± 0.05*	8
R395C	−25.0 ± 1.3*	7.3 ± 0.5	−71.4 ± 5.2	8.4 ± 1.3	N.C.	0.30 ± 0.04	7
Domain II
E755C	−18.8 ± 5.3	9.0 ± 1.1	N.D.	N.D.	N.D.	0.36 ± 0.09	4
C753A	−24.0 ± 1.4	6.5 ± 0.3	−64.9 ± 1.7	5.8 ± 0.6	N.C.	0.28 ± 0.02	4
I751C	−20.3 ± 2.1	6.8 ± 0.7	N.D.	N.D.	N.D.	0.39 ± 0.06	4
R750C	−15.7 ± 3.2	8.2 ± 0.3	N.D.	N.D.	N.D.	0.34 ± 0.05	6
Domain III
F1236C	−23.4 ± 2.4	8.2 ± 1.0	−68.0 ± 1.8	6.8 ± 0.5	Slow	0.33 ± 0.02	9
T1235C	−22.1 ± 1.4	7.6 ± 0.5	−70.1 ± 2.2	6.9 ± 0.5	Slow	0.30 ± 0.02	10
A1234C	−15.5 ± 2.1	8.9 ± 0.4	−76.5 ± 0.9*	6.2 ± 0.2	Slow	0.25 ± 0.02*	5
Domain IV
A1529C	−19.5 ± 1.8	5.3 ± 0.3*	−66.9 ± 1.0	6.4 ± 0.5	Slow	0.28 ± 0.03	5
S1528C	−18.4 ± 2.5	7.8 ± 0.3	−71.8 ± 1.2*	7.7 ± 0.4	N.C.	0.29 ± 0.03	5
T1527C	−26.7 ± 2.6*	7.9 ± 0.7	−72.0 ± 2.0*	8.5 ± 0.3	N.C.	0.29 ± 0.04	7
T1526C	−19.9 ± 1.6	8.8 ± 0.9	−65.3 ± 1.9	7.3 ± 0.6	N.C.	0.31 ± 0.05	5

N.C., not significantly changed; N.D., not determined.

^* P < 0.05 versus WT.