TABLE I.
Affinity of Chimeric Channels for Dequalinium
| Construct | IC50 for Deq block |
|---|---|
| CNGA1 | 189 ± 4.19 nM |
| CNGA1-R342Y | 91 ± 0.1 nM |
| CNGA1-R342D | 123 ± 0.2 nM |
| CNGA1-S5b | 260 ± 0.1 nM |
| CNGA1-P | 80 ± 0.1 nM |
| CNGA1-S6a | 218 ± 8.46 nM |
| S4/S5-CNGA1 | 360 ± 8.7 nM |
| S4/S5-CNGA2 | 2.7 ± 0.33 μM |
| CNGA2 | 2.4 ± 0.29 μM |
Regions that affect binding of dequalinium to CNG channels. A CNGA1 channel background (denoted as the CNGA1 prefix in the names of the constructs) was used to construct chimeras where specific regions where replaced by the corresponding regions of CNGA2, except for S4/S5-CNGA2 chimera where the background was that of CNGA2. The mean IC50 values for each of the constructs shown were obtained in the presence of 2 mM cGMP.