FIGURE 4.

Comparison of GIP(1-42), GIP(1-30)NH₂ and Tirzepatide efficacy (log(τ/KA)) at the human WT and E354Q GIP receptors in transfected Cos7 cells (A-E). To allow direct comparisons between the receptors the operational model was performed on data normalized to the maximal response produced by GIP (1-42) at the WT GIP receptor, for both the WT and E354Q GIP receptor. Data points are the mean ± s.e.m of the combined data from 3 (pAKT, pERK1/2 and pCREB) or 5 (cAMP and IP1) independent experiments. *p < 0.05 by unpaired Student’s t-test comparing the log (τ/KA) of the same peptide at the WT and E354Q GIP receptors for each signaling pathway.