. 2018 Jul 29;596(17):4091–4119. doi: 10.1113/JP276332

Table 1.

Summary of ClC‐3 ion transport and gating charge

	Anion, pH	I _SS (pA/pF)a	ΔV _m a ^, b	I _SS (pA)c	Q _max (fC)d	Q/I _SS c	V _1/2 of Q–V
Control HEK	Cl⁻, pH 7.35e	3.4 ± 0.5 (22)	<0.5 mV		n.d.
	SCN⁻, pH 7.35d	29.1 ± 1.9 (4)	<0.5 mV		n.d.
ClC‐5 WT	Cl⁻, pH 7.35e	80.0 ± 8.4	2.8 mV	1573 (11)	204 ± 25 (9)	0.05 ± 0.01 ^*	126 ± 4 mV
	SCN⁻, pH 7.35d	367 ± 39 (9)	13 mV§	11,482 (9)	68 ± 19% (4)	n.m.	n.m.
ClC‐3a WT	Cl⁻, pH 7.35e	5.0 ± 0.8	<0.5 mV	111 (8)	n.d.	n.d.	n.d.
ClC‐3b WT	Cl⁻, pH 7.35	12.9 ± 4.3 (9)	<0.5 mV	159 (9)	109 ± 31 (8)	0.69 ± 0.16 (8)	82 ± 3 mV (7)
ClC‐3/5	Cl⁻, pH 7.35	4.0 ± 0.6 (6)	<0.5 mV		n.d.	n.d.	n.d.
ClC‐5/3 WT	Cl⁻, pH 7.35e	45.4 ± 2.4	1.7 mV	800 (28)	755 ± 76	0.86 ± 0.03	78 ± 1 mV
	28 mM Cl⁻	19.1 ± 3.3	0.6 mV	298 (5)	817 ± 77	1.67 ± 0.17†	107 ± 1 mV†
	SCN⁻, pH 7.35f	136 ± 9 (6)	6.7 mV	2865 (6)	94 ± 7%	0.18 ± 0.02	84 ± 5 mV†
	Cl⁻, pH 6.0	36.1 ± 3.4†	1.8 mV	832 (7)	74 ± 3%	n.m.	89 ± 4 mV†
	Cl⁻, pH 5.0g	25.6 ± 3.2†	1.5 mV	468 (12)	40 ± 3%	n.m.	107 ± 2 mV†
E224A	Cl⁻, pH 7.35e	26.2 ± 6.3	1.1 mV	442 (5)	n.d.	n.d.
	SCN⁻, pH 7.35f	467 ± 40	20 mV§	11,228 (5)	n.d.	n.d.
M531A	Cl⁻, pH 7.35e	67.2 ± 6.4 ^*	2.6 mV	1250 (17)	504 ± 39 ^*	0.35 ± 0.03 ^*	79 ± 1 mV ^*
	SCN⁻, pH 7.35f	150 ± 10	4.7 mV	2628 (2)	128 ± 24%	0.14 ± 0.02	103 ± 1 mV†
	Cl⁻, pH 6.0	53.5 ± 10 (8)	2.2 mV	1067 (8)	83 ± 5% (8)	n.m.	97 ± 4 mV
	Cl⁻, pH 5.0g	30.5 ± 5.0 (8)	1.3 mV	596 (8)	34 ± 2% (8)	n.m.	112 ± 5 mV†
E281Q	Cl⁻, pH 7.35e	4.5 ± 0.6	<0.5 mV	97 (23)	1663 ± 144^*	25.6 ± 9.4	88 ± 1 mV ^*
	SCN⁻, pH 7.35f	24 ± 3	<1 mV	387 (3)
	Cl⁻, pH 6.0	3.3 ± 1.6 (7)	<0.5 mV		98 ± 3% (8)	n.m.	106 ± 3 mV†
	Cl⁻, pH 5.0g	n.m.	<0.5 mV		87 ± 4% (12)	n.m.	131 ± 3 mV†
E224A/E281Q	Cl⁻, pH 7.35e	22.8 ± 5.0	1.1 mV	446 (5)	n.d.	n.d.
	SCN⁻, pH 7.35f	464 ± 38	23 mV§	12,960 (5)	n.d.	n.d.
E224A/Y572S	Cl⁻, pH 7.35e	279 ± 26	13 mV§	5128 (6)	n.d.	n.d.
	SCN⁻, pH 7.35f	629 ± 100	29 mV§	18,328 (4)	n.d.	n.d.
Y572S	Cl⁻, pH 7.35e	166 ± 11	8.0 mV §	4892 (28)	198 ± 20 (15) ^*	0.04 ± 0.005 ^*	72 ± 3 mV
	13 mM Cl⁻	43.8 ± 5.8	1.9 mV	1068 (3)	462 ± 110†	0.22 ± 0.02†	114 ± 4 mV†
	SCN⁻, pH 7.35f	93 ± 13	4.5 mV	2432 (13)	214 ± 31% (8)†	0.09 ± 0.02	80 ± 5 mV
Y572V	Cl⁻, pH 7.35e	220 ± 40	13 mV§	8328 (7)	208 ± 37 (5)*	0.03 ± 0.02*	74 ± 2 mV
	SCN⁻, pH 7.35f	83 ± 13	4.8 mV	2500 (7)	83 ± 14% (5)	0.06 ± 0.01 (5)	87 ± 5 mV
Y572F	Cl⁻, pH 7.35e	55.4 ± 5.5 ^*	2.0 mV	949 (10)	1162 ± 161 ^*	0.88 ± 0.05 ^*	90 ± 2 mV ^*
	SCN⁻, pH 7.35f	69 ± 5†	2.5 mV	1197 (8)	72 ± 2% (5)†	0.44 ± 0.04 (5)	83 ± 4 mV
Y572S/E281Q	Cl⁻, pH 7.35e	11.4 ± 1.4‡	<1 mV	210 (11)	959 ± 108‡	1.77 ± 0.34‡	115 ± 1 mV‡
Y572F/E281Q	Cl⁻, pH 7.35	7.3 ± 1.1	<1 mV	154 (13)	1384 ± 141	11.0 ± 2.2‡	103 ± 2 mV‡
Y572H/E281Q	Cl⁻, pH 7.35	4.8 ± 0.9	<1 mV	86 (7)	844 ± 70‡	3.62 ± 0.58‡	131 ± 2 mV‡

Values are means ± SEM; numbers in parentheses indicate number of experiments or observations. ^aValues at +115 mV applied potential. I _SS (pA/pF): steady‐state transport current density. ^bΔV _m: average R _S‐associated voltage error at steady state. ^c I _SS (pA): average current magnitude at a corrected voltage of +115 mV; Q/I _SS: average ratio at a corrected voltage of +115 mV. ^d Q _max determined in control saline (pH 7.35, 130 mM Cl⁻); %Q is normalized to control Q _max value. ^e130 mM Cl⁻ control saline at pH 7.35. ^f122 mM SCN⁻/8 mM Cl⁻ saline at pH 7.35. ^gExternal saline included 100–300 μM phloretin to block endogenous I _Cl,acid. Symbols: ^*differs significantly (P ≤ 0.05) from value in ClC‐5/3 wild‐type; ^†differs significantly (P ≤ 0.05) from value in control saline; ^‡differs significantly (P ≤ 0.05) from E281Q “wild‐type”; ^§greater than 5% average steady‐state voltage error at +115 mV applied potential. n.d., undetected/not present; n.m., not measured/uninterpretable.