Table 2. Voltage dependent gating and... | Rockefeller University Press

Table 2.

Voltage dependent gating and free energies of channel gating for I696X and W697X in the presence of 100 µM capsaicin

Channel	V_0.5^a	z_g^a	g_max^a	P_min^b	ΔG_o(I)^c	ΔG_o(V)^d	ΔG_o^e
	mV		nS		kcal/mol	kcal/mol	kcal/mol
TRPV1	NA	NA	124 ± 7	0.95 ± 0.01	−2.67 ± 0.81	NA	−2.67 ± 0.81
I696A	64 ± 5	0.55 ± 0.06	60 ± 7	0.01 ± 0.06	2.67 ± 0.63	0.63 ± 0.15	3.30 ± 0.98
I696V	70 ± 8	0.75 ± 0.05	77 ± 15	0.21 ± 0.05	0.77 ± 0.12	1.33 ± 0.11	1.90 ± 0.31
I696L	72 ± 7	0.76 ± 0.09	86 ± 10	0.50 ± 0.07	0.05 ± 0.02	1.26 ± 0.25	1.30 ± 0.51
I696M	48 ± 9	0.79 ± 0.04	79 ± 9	0.15 ± 0.11	1.05 ± 0.05	0.57 ± 0.12	1.62 ± 0.51
I696H	63 ± 6	0.79 ± 0.07	70 ± 8	0.29 ± 0.04	0.52 ± 0.09	1.13 ± 0.20	1.65 ± 0.36
W697Y	49 ± 9	0.85 ± 0.3	67 ± 16	0.51 ± 0.05	−0.02 ± 0.01	0.98 ± 0.09	0.95 ± 0.17
W697H	66 ± 8	0.87 ± 0.4	62 ± 12	0.67 ± 0.03	−0.40 ± 0.06	1.30 ± 0.12	0.90 ± 0.14
W697V	68 ± 7	0.89 ± 0.3	30 ± 6	0.57 ± 0.04	−0.24 ± 0.03	1.30 ± 0.18	1.06 ± 0.19
W697D	8 ± 11	0.72 ± 0.2	133 ± 11	0.87 ± 0.02	−1.05 ± 0.08	0.14 ± 0.06	−0.91 ± 0.61
W697N	57 ± 10	0.81 ± 0.3	106 ± 13	0.81 ± 0.03	−0.80 ± 0.07	1.11 ± 0.36	0.31 ± 0.31

Channel	V_0.5^a	z_g^a	g_max^a	P_min^b	ΔG_o(I)^c	ΔG_o(V)^d	ΔG_o^e
	mV		nS		kcal/mol	kcal/mol	kcal/mol
TRPV1	NA	NA	124 ± 7	0.95 ± 0.01	−2.67 ± 0.81	NA	−2.67 ± 0.81
I696A	64 ± 5	0.55 ± 0.06	60 ± 7	0.01 ± 0.06	2.67 ± 0.63	0.63 ± 0.15	3.30 ± 0.98
I696V	70 ± 8	0.75 ± 0.05	77 ± 15	0.21 ± 0.05	0.77 ± 0.12	1.33 ± 0.11	1.90 ± 0.31
I696L	72 ± 7	0.76 ± 0.09	86 ± 10	0.50 ± 0.07	0.05 ± 0.02	1.26 ± 0.25	1.30 ± 0.51
I696M	48 ± 9	0.79 ± 0.04	79 ± 9	0.15 ± 0.11	1.05 ± 0.05	0.57 ± 0.12	1.62 ± 0.51
I696H	63 ± 6	0.79 ± 0.07	70 ± 8	0.29 ± 0.04	0.52 ± 0.09	1.13 ± 0.20	1.65 ± 0.36
W697Y	49 ± 9	0.85 ± 0.3	67 ± 16	0.51 ± 0.05	−0.02 ± 0.01	0.98 ± 0.09	0.95 ± 0.17
W697H	66 ± 8	0.87 ± 0.4	62 ± 12	0.67 ± 0.03	−0.40 ± 0.06	1.30 ± 0.12	0.90 ± 0.14
W697V	68 ± 7	0.89 ± 0.3	30 ± 6	0.57 ± 0.04	−0.24 ± 0.03	1.30 ± 0.18	1.06 ± 0.19
W697D	8 ± 11	0.72 ± 0.2	133 ± 11	0.87 ± 0.02	−1.05 ± 0.08	0.14 ± 0.06	−0.91 ± 0.61
W697N	57 ± 10	0.81 ± 0.3	106 ± 13	0.81 ± 0.03	−0.80 ± 0.07	1.11 ± 0.36	0.31 ± 0.31

The parameter values obtained from the best fit of the g-V curves to a Boltzmann distribution (Figs. 5 B and 6 A). Free energies were estimated assuming a two-state gating model.

P_min denotes the normalized conductance at hyperpolarized potentials (g_min/g_max), where g_min has been obtained for the best fit of the g-V curve to a Boltzmann distribution.

The free energy of the voltage-independent component, obtained as –RT ln[(P_min/(1 − P_min)].

The free energy of the voltage-dependent component, obtained as z_gFV_0.5.

The total free energy of the gating process, obtained as ΔG_o(I)+ΔG_o(V).

Data are given as mean ± SEM, with n ≥ 5. NA, not applicable.

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