Figure 4: Inserting an unstructured peptide between the transmembrane core domain and the intracellular domains does not affect general channel function.

Averaged calcium imaging recordings of wild-type (WT) TRPV1 and two insertion mutants of interest, F430_3aa and E693_8aa, activated by extracellularly applied (as indicated by white bars) 10 μM capsaicin, 130 mM Mg2+ and low pH (pH 4.6) respectively. 3 mM ionomycin (as indicated by gray bars) was applied at the end of each imaging experiment to get the maximum fluorescence change. The total number of cells tested is given in each panel. The error bar represents standard error of means. Change in fluorescence intensity, ΔF, was calculated as the difference between the equilibrium level before stimulus application and after application of ionomycin.