TABLE 1.

Properties of mHCN4 channels and mutants

All recordings were performed with 100 μm cAMP in the intracellular solution, except as indicated in the first two rows. Statistical values from t tests for the mutants were obtained by comparison with mHCN4L (see Footnotes b–d).

	na	V1/2	τactivation
			at −180 mV	at −50 mV (n)
mHCN4L (no cAMP)	5	−144.02 ± 1.23	0.33 ± 0.02	0.35 ± 0.03 (4)
mHCN4S (no cAMP)	4	−147.59 ± 1.26	0.48 ± 0.05	0.26 ± 0.04 (5)
mHCN4L	6	−123.17 ± 0.78	0.15 ± 0.02	0.35 ± 0.07 (4)
mHCN4S	6	−140.97 ± 1.98	0.35 ± 0.01	0.30 ± 0.07 (3)
Del7	7	−129.88 ± 2.25b	0.26 ± 0.02
Del12	6	−141.64 ± 2.77c	0.49 ± 0.16b
RKR to AAA	5	−133.77 ± 2.84d	0.33 ± 0.03c
K3A	4	−120.56 ± 3.85	0.15 ± 0.02
R9A	5	−137.82 ± 1.93c	0.54 ± 0.12d
K10A	6	−132.43 ± 3.35b	0.39 ± 0.11
R11A	6	−119.33 ± 3.11	0.21 ± 0.01b
K22A	5	−131.59 ± 3.69b	0.27 ± 0.04b

^a These numbers are for activation recordings; the numbers for deactivation (τ) are listed in parentheses after the τ value.

^b p < 0.05.

^c p < 0.001.

^d p < 0.01.