Table 3.

Effects of mutating aromatic residues at the M4–M1/M3 interface on nAChR function

Dose responsea
Mutation	TMD α-helix	EC50 (μM)	pEC50 (M)	Hill slope	n
WT		7.61	5.12 ± 0.07	1.70 ± 0.47	50
α subunit
αF227A	M1	6.51	5.20 ± 0.09	1.43 ± 0.16	8
αF233A	M1	2.63	5.58 ± 0.05b	1.63 ± 0.20	9
αY234A	M1	No currentc	—	—	8
αY277A	M3	11.2	4.96 ± 0.08b	1.78 ± 0.58	8
αF280A	M3	4.25	5.38 ± 0.11b	1.56 ± 0.29	8
αF284A	M3	4.80	5.32 ± 0.07b	1.33 ± 0.21	9
αF414A	M4	4.47	5.36 ± 0.09b	1.76 ± 0.34	10
αF426A	M4	2.02	5.71 ± 0.14b	1.80 ± 0.76	11
β subunit
βF244A	M1	4.46	5.35 ± 0.14b	2.23 ± 0.77	9
βY245A	M1	7.44	5.13 ± 0.10	1.56 ± 0.16	7
βY288A	M3	5.43	5.27 ± 0.10b	1.77 ± 0.30	8
βF291A	M3	10.5	4.98 ± 0.09b	1.66 ± 0.35	9
βF448A	M4	4.36	5.38 ± 0.15b	1.63 ± 0.48	8
βF452A	M4	10.5	4.98 ± 0.07	1.69 ± 0.11	8
βF464A	M4	8.55	5.08 ± 0.11	1.38 ± 0.19	10
δ subunit
δF247A	M1	11.2	4.95 ± 0.10b	1.45 ± 0.12	9
δY248A	M1	3.67	5.44 ± 0.12b	1.57 ± 0.22	9
δF291A	M3	6.18	5.21 ± 0.08	1.62 ± 0.16	9
δF294A	M3	3.86	5.41 ± 0.07b	1.72 ± 0.13	8
δF468A	M4	5.83	5.25 ± 0.10	1.60 ± 0.27	7
ε subunit
εY242A	M1	8.12	5.09 ± 0.04	1.67 ± 0.11	10
εF243A	M1	8.02	5.10 ± 0.10	1.78 ± 0.19	9
εF287A	M3	12.7	4.90 ± 0.06b	1.51 ± 0.13	9
εF290A	M3	6.14	5.21 ± 0.12	2.06 ± 0.36	7
εF439A	M4	8.59	5.07 ± 0.07	1.81 ± 0.08	8
εF446A	M4	8.89	5.06 ± 0.07	1.51 ± 0.18	9
εF454A	M4	3.90	5.42 ± 0.10b	1.80 ± 0.25	8

^aMeasurements performed 1 to 4 days after cRNA injection (V_hold ranging from −20 to −80 mV). Error values are represented as standard deviation.

^bp < 0.001 relative to WT via one-way ANOVA followed by Dunnet’s post hoc test.

^cNo significant current observed up to 4 days after cRNA injection.