Each experimental genotype is Gr89a-GAL4; UAS-GrX. (a) Response profiles of both parental controls and flies expressing UAS-Gr22b in S-a bitter neurons. Asterisks indicate responses that are different from both parental controls (two-way ANOVA, with Bonferroni multiple comparisons correction; p ≤ 0.0001, except BER: p ≤ 0.0005. n ≥ 7). Response profiles generated by expression of Gr22b, Gr58c, Gr2a, Gr10a in S-a bitter neurons (b) and I-b bitter neurons (d). Asterisks indicate responses that are different from the parental control (two-way ANOVA, with Bonferroni multiple comparisons correction; p ≤ 0.0001, except that for S-a sensilla, p≤0.001 for Gr2a/SPS, Gr2a/LOB, Gr10a/DEN, Gr10a/LOB; p ≤ 0.01 for Gr2a/DEN, Gr2a/AZA, Gr58c/ARI; p≤0.03 for Gr10a/SAP, Gr10a/SPS, and Gr58c/UMB. For I-b sensilla, p ≤ 0.001 for Gr22b/TPH; p≤0.01 for Gr22b/THE, Gr22b/CAF, Gr58c/LOB, and Gr58c/TPH; p ≤ 0.05 for Gr58c/CAF and Gr58c/UMB. n ≥ 6). (c) Expression of Gr2a and Gr22b in S-a bitter neurons conferred suppression of the endogenous response to SPS. Asterisks indicate responses that are different from both parental controls (p ≤ 0.002, n ≥ 18). Concentrations are graphed on a logarithmic scale.