Fig. 3
From: An allosteric ligand-binding site in the extracellular cap of K2P channels
Substitutions of key residues in the extracellular cap of TRAAK channel. a Multiple sequence alignment for the extracellular caps of TREK-1, TREK-2, and TRAAK channels. b Dose-dependent inhibition of TKDC on the WT and mutant TRAAK channels. c Histograms summarizing the half-inhibitory concentrations of TKDC for the WT (n = 8), A35Q (n = 8), E38T (n = 6) and V42Q (n = 7) mutant TRAAK channels. Mutations of these residues in the extracellular cap showed enhanced inhibitory effects of TKDC. IC50 values were obtained via dose–response fitting. One-way ANOVA with post hoc LSD test was used for statistical analysis [F (3, 20) = 18.551]; ** indicates P < 0.01. The data are shown as the mean ± s.e.m. d, e Docking modes of TKDC in A35Q TRAAK d, in V42Q TRAAK e, and in E38T TRAAK f. The protein is shown as a cartoon. TKDC and key residues are shown as sticks
