FIGURE 1.

Signaling properties of the WT-AT₁ receptor and the biased mutants on the β-arrestins and inositol phosphate pathways. HEK293 cells were transfected with the indicated receptor, and their recruitment of β-arrestin1 (A), β-arrestin2 (C), and IP₁ production (E) was assayed as described under “Experimental Procedures.” Each point represents the mean ± S.D. of duplicate determinations of a typical experiment, which is representative of at least three independent experiments. Bar graphs represent the mean ± S.E. for the maximum increase in β-arrestin1 (B) and β-arrestin2 (D) recruitment relative to the WT-AT₁ receptor after normalizing for each receptor's level of expression.