Receptor and GPCRome screening of Mu8.1.

(A) Primary radioligand binding assay of Mu8.1 (10 uM) at 52 receptors and ion channels (x-axis). Plotted values represent means (n = 4), and error bars are ±SEM. Arrows show 2 receptors, 5-HT3 and histamine H1, with inhibition >50% that were selected for secondary testing. Source data and quantifications provided in S8 Data. (B) Secondary binding assay of the 5-HT3 (left) and H1 (right) receptors. Plotted values represent means (n = 3), and error bars are ±SEM. The results demonstrate that the 2 initial hits from S11A were false positives. (C) PRESTO-Tango screen of Mu8.1 (10 μM) at 318 human GPCRs (x-axis). Plotted values represent means ±SD. The arrow indicates a potential hit (ADRAC2) that met the cutoff for further testing. However, a closer examination of the data showed a false positive due to an outlier. (TIF)