Fig. 6: helix E controls cAMP affinity in HCN1.
From: A high affinity switch for cAMP in the HCN pacemaker channels
a Representative current traces (recorded at −30, −70 and −120 mV) of HCN1 FL (black), ΔE (green), D629A (purple) and R549E (gray). b Activation curves of HCN1 FL, ΔE, D629A and R549E; colors as in panel a. V1/2 and k values are reported in Supplementary Table 2 together with the details on statistical analysis. Data are shown as mean ± SEM. c cAMP-induced shift in V1/2 in constructs from a. For HCN1 constructs, the reference value is that of the mutant R549E, which is virtually cAMP-insensitive17. Data are presented as mean ± SEM.
