Figure 9.

Alanine mutation of ECL2 and ECL3 of AMY₃R alters pERK efficacy (log τ_c) in a peptide-specific manner. Peptide efficacy (log τ) was derived from operational fitting of concentration–response curves in pERK for alanine mutation of ECL2 (A–E) and ECL3 (F–J), and corrected for cell surface receptor expression to yield log τ_c. Significance of mutation effect was established by comparison of the wild-type to the other receptor mutants following one-way ANOVA and Dunnett’s post-test with P < 0.05 accepted as significant. Mutants that significantly reduced log τ_c are colored orange (≤10-fold change), or red (>10-fold change). Where data were insufficiently robust to derive a reliable value for log τ_c no symbol is shown (ND). Quantitative data are reported in Table 5.