Fluorescence changes of BmGr9 and mutants when stimulated with 100 mM d -fructose. Q443E and Q445A substitutions yield channels that are more active than those of the wild-type BmGr9. Bars are mean s.e.m. with independent samples shown as open circles; grey bars indicate statistically significant activity compared to that of GCaMP alone. Statistical significance was determined using one-way ANOVA followed by Dunnetts multiple comparison tests (*** P < 0.0001, * P = 0.012).
