(a–b) Examination of the effects of p426-r37L1 on reporter signal in (a) CRE-luc and (b) CAMYEL assays. HEK293 cells were transiently co-transfected with the CRE-luc reporter or the CAMYEL BRET biosensor together with incorrect or corrected GPR37L1 construct or β2-adrenoceptor, as indicated. ‘Empty’ refers to empty plasmid DNA. For CRE-luc assay, data represent n=2 biological replicates each performed in triplicate on separate days; each data point is the average of the technical replicates for the corresponding biological replicate, and the bar height indicates the mean of biological replicates. For CAMYEL assay, data represent n=1 with technical replicates shown as dots. RLU, relative light units; FSK, forskolin. (c) Western blot for transient HEK293 cellular expression of r37L1, corrected GPR37L1 or controls, as indicated. Cerebellum from a male C57BL/6J mouse was used as a positive control. Dashed lane contained protein ladder only. Image is n=1. All raw data is available in the accompanying Source Data file.